[Biochemical values in erythrocytes before freezing and after freezing at low temperatures]. / Nekteré biochemické hodnoty u erytrocytu pred zmrazením a po zmrazení za nízkých teplot.

The authors tested three ways of freezing red cell concentrates with glycerin. At -30 degrees C in a deep freezer; on a Planer at the rate of 1 degree C per minute and by immersion into liquid nitrogen to -196 degrees C, stored in cryo-containers in liquid nitrogen. In samples processed in all three ways, incl. the follow-up of glycolysis in red cell concentrates in acid-citrate-dextrose solution, the levels of the following enzymes were assessed: glucose-6-phosphate dehydrogenase, glutathione reductase, pyruvate kinase. In addition also the levels of sodium, potassium, pH and glucose were assessed. The enzyme estimations of all three mentioned enzymes after triple rinsing with saline in the samples immersed in liquid nitrogen at -196 degrees C had the most acceptable values and smallest losses after rinsing.

[Total lipid levels in erythrocyte concentrates before and after freezing]. / Celkový obsah nekterých lipidu v erytrocytárních koncentrátech pred zmrazením a po zmrazení.

The authors investigated changes of total lipids, cholesterol, triacyglycerols in red cell concentrates collected into acid-citrate-dextrose solution before freezing with glycerin and after freezing with glycerin to -30 degrees C in a deep freezer and to -196 degrees C by immersion into liquid nitrogen. It was revealed that the triacylglycerol levels after deglycerolization increased approximately three times. In transfusions of major amounts of thus processed blood the possibly impaired tissue saturation with oxygen will have to be taken into account. It may be concluded that lipids released from red cells impaired as a result of freezing may contribute to the formation of undesirable aggregates in blood.

Biological risks of the conservation of transfusion preparations by low temperature.

When the blood or bone marrow collections are provided and treated subsequently, two types of biohazards may occur. The first of them resides in bacterial contamination at collection and following manipulation. The second is represented by endengering both recipients and staff with prelevement of infected tissues. Contemporary blood collections are at most risk from the transfer of infectious hepatitis and HIV virus. Possible risk-factors are analysed from the transfer of serious infections through the use of hypothermic and cryothermic conservation as well as freeze-drying.

[Cooperation between the volunteer bone marrow donor section at the Institute of Hematology and Blood Transfusion, Prague, and the Caitlin Raymond Registry of Bone Marrow Donor Banks. 1 year experience]. / Spolupráce stanice dobrovolných dárcu kostní drene v Ustavu hematologie a krevní transfúze, Praha, a Caitlin Raymond Registry of Bone Marrow Donor Banks. Rocní zkusenosti.

The authors report on their one-year experience of co-operation with the Caitlin Raymond Registry of Bone Marrow Donor Banks in the selection of suitable bone marrow donors. Out of the 280 requirements received a total of seven donors were singled out - identical in HLA-AB antigens though unsuitable in the DR system.

[The Apple II e microcomputer as a databank for registering special donors]. / Mikropocítac "Apple II e" jako databanka pro registraci specialních dárcu.

The authors introduced in the Institute of Haematology and Blood Transfusion in Prague records of special donors, voluntary donors of bone marrow and voluntary donors for the separator using the microcomputer Apple II and the system ArchTex. These provisions make it possible to select a suitable donor much more quickly than by the hitherto used system of cards which, however, still are essential for the work of the special donor station.

Mylecytan-sensitive and Mylecytan-resistant strains of inbred SPF mice.

In an attempt to induce aplasia of the bone marrow, to several strains of inbred SPF mice Mylecytan Spofa was administered. Evidence was provided that basically two groups can be differentiated: Mylecytan-resistant (C57 Black/ 10, ICR and F1 hybrid (Aph X C57 Black/ 10) and Mylecytan sensitive (CBA, C3H and Aph) strains. This fact should be taken into consideration in the interpretation of results of investigations evaluating the action of cytostatic preparations as well as when studying other relationships such as e. g. the aetiopathogenesis of aplasia of the bone marrow, etc.

Progenitor white cells and serum inhibitors in patients with bone marrow aplasia.

In patients with various blood diseases, especially with bone marrow hypoplasia following parameters were determined: presence of antibodies against autologous bone marrow, number of granulocyte-progenitor cells in short term bone marrow cultures and stimulating or inhibiting factors in patient's serum influencing the proliferative activity of bone marrow colonies. The results as well as possible clinical aspects are discussed.