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R Moog

Publications and source records attributed to R Moog.

8 recordsLinked to original sources

[Importance of the interface position in thrombocytapheresis with the AS 104 cell separator].

In plateletpheresis with the Fresenius AS 104 the interface position influences the separation efficiency and the cell contamination of the platelet concentrate. The aim of the present study is to improve the purity of the platelet concentrate by changing the interface position. Increasing interface position results in rising separation efficiency and cell contamination. Alternating interface position gives the best result with significantly lower leukocyte contamination and only a slight decrease of separation efficiency. Nevertheless we prefer separations with variable interface position to reduce an immunisation of the recipient by white blood cells.

Blood Volume

[Plateletpheresis with the new cell separator A 201 (Baxter)].

This report deals with our first experiences in testing the new system A 201 (Baxter Fenwal Division) for plateletpheresis in routine application. The apparatus developed from the well-known plasmapheresis equipment Autopheresis C only requires a single venipuncture and uses two separation devices. The platelet cell device produces a primary platelet concentrate. After the donor's disconnection, the platelet-containing plasma is separated into 400 ml of red cell and leucocyte-free plasma and the platelet concentrate, which is done by a rotating membrane filter of the same instrument. Plateletpheresis was performed on 34 healthy donors (26 male and 8 female), formerly experienced by other apheresis procedures. Different samples were drawn from the donors before, during and after apheresis. In comparison with other apheresis procedures there were no significant differences in the harvested platelets (3 +/- 0.7 x 10(11), but the preparations showed a higher contamination of leucocytes (3.7 +/- 3.7 x 10(8). This means a considerable disadvantage and requires improvement. Yet the advantages of this separator are obvious: Reduction of needed anticoagulation to only 6% of processed blood volume, single needle technique, safety of operation and, due to less size, more mobility.

Blood Donors

[Thrombocytapheresis with the (Baxter) A 201 cell separator--initial data of biocompatibility].

The cell separator A 201 was a new platelet pheresis prototype designed to carry out a discontinuous apheresis while platelet-rich plasma (PRP) is sampled continuously. After donation, a platelet concentrate (PC) and a fresh frozen plasma was collected from the PRP by the plasma cell-C device. The PC contained 2.6 +/- 0.7 x 10(11) platelets with a leucocyte contamination of 3.9 +/- 3.9 x 10(8) and an erythrocyte contamination of 3.0 +/- 3.0 x 10(8). The fresh frozen plasma was nearly cell-free. Prior, during and after apheresis we analysed hemolysis and coagulation parameters. There was no evidence for hemolysis. The analysis of the coagulation factors and of the Thrombin-Antithrombin III-complex, however, gave a hint of an activation of coagulation.

Biocompatible Materials

[Comparison of 3 types of cell separators].

The aim of the present investigation was to compare the efficiency of three commercially available cell separators with respect to thrombocyte yields. In addition, advantages and disadvantages of the different cell separator types were studied. There was no difference in the total number of platelets harvested by the different cell separators. In contrast the thrombocyte count of packages from the V 50 device was significantly lower as compared with the others (p = 0.05). We conclude that the cell separators tested are comparable with respect to the efficiency of processing platelet concentrates. However, the larger amount of plasma of the V 50 might be a disadvantage in some circumstances. The AS 104 has advantages in the handling and the duration of cell separation. In addition it offers technical improvements such as control of the ACD flow by a separate adjustable pump and a hemolysis detector.

Blood Transfusion

Adaptation to shift work--experimental approaches with reduced masking effects.

Chronobiological characteristics of night and shift work, features of the adaptive process to be expected are briefly considered in the first part of the paper. Demands for experimental routines to imitate these situations and the need for routines reducing masking effects are discussed. Experiments meeting these demands are reviewed. Practical considerations are derived. Interindividual differences of the circadian system are taken into account.

Adaptation, Physiological

Circadian adaptation to fast and slow rotating shift systems.

Healthy male subjects were exposed to various shift systems. Adaptation and adjustment of the circadian systems were followed-up twice a week on so-called control days to reduce masking effects. With respect to the 24-hr minimum of rectal temperature and to the longest spontaneous sleep period on control days, the slower the shift system rotated and the later the individual circadian phase position was, the more subjects were able to follow the different shift systems. Subjects with stable phase shifts between the shift days always exhibited a phase shift of 1 hr per day.

Adaptation, Physiological