Skylab experiment results: Hematology studies

Kimzey, S. L.; Ritzmann, Stephan E.; Mengel, Charles E.; Fischer, Craig L.

doi:10.1016/0094-5765(75)90050-8

Cited by 23 publications

(17 citation statements)

References 3 publications

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“…Also the values of the Skylab experiments [8,9] appeared to us surprisingly high. Using the same buoyancy method, Nakashima et al [12] already had indicated a possible role of thermal expansion in biasing the results.…”

Section: Discussionmentioning

confidence: 96%

“…They had been introduced for cell separation [1] in 1960 because of their biological inertness and their extremely low aqueous solubility. The method of Danon and Marikovsky [2] has also been used in the recent Skylab experiments [8,9]. It is well established that age related changes in erythrocytes in vivo are strongly connected with changes in density [4,13,14].…”

mentioning

confidence: 99%

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On the Influence of Temperature on the Measurement of Density Distribution of Erythrocytes. Bedeutung der Temperatur für die Bestimmung der Dichteverteilung von Erythrocyten

Haidmayer¹,

Kenner²,

Hinghofer‐Szalkay³

1980

Biomedizinische Technik/Biomedical Engineering

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In 1964, Danon and Marikovsky described a simple method for the determination of density distribution of erythrocytes in blood by centrifuging heparinized blood with phthalate esters of different densities. By using this buoyancy method within our experiments on blood density in babies with suspected risk for SIDS (sudden infant death syndrome) a difference between the values of mean erythrocyte densities measured with this method and between values measured with the mechanical oscillator technique became evident. It is shown in this study that this error is based on the fact that mixtures of phthalate esters have a higher thermal expansion than erythrocytes. Due to a rise in temperature during the centrifugation period (15 min) the density of the phthalate esters decreases more than the density of the erythrocytes. Thus, a larger percentage of heavier erythrocytes is indicated. Our exact measurements allow to correct for this error if the temperature within the centrifuge is known.Schlüsselwörter: Erythrocyten, Temperatur, Dichteverteilung Danon und Marikovsky beschrieben 1964 eine einfache Methode zur Bestimmung der Dichteverteilung von Erythrocyten im Blut, indem sie Heparinblut mit Phthalsäureestern verschiedener Dichte zentrifugierten. Bei Anwendung dieser Methode im Rahmen unserer Blutdichteuntersuchungen bei Säuglingen mit einem vermutlichen Risiko für SIDS (sudden infant death syndrome) zeigte sich, daß die solcherart ermittelten Werte der mittleren Erythrocytendichte von denjenigen Werten differierten, die mit der Biegeschwingermethode gemessen worden waren. Unsere Studie hier zeigt nun, daß der Fehler auf die Tatsache zurückzuführen ist, daß Gemische von Phthalsäureesten einen größeren thermischen Ausdehnungskoeffizienten besitzen als Erythrocyten. Entsprechend dem Temperaturanstieg in der Zentrifuge während des Zentrifugationsvorganges (15 Min.) nimmt die Dichte der Phthalsäureester stärker ab als die Dichte der Erythrocyten. Unsere exakten Messungen ermöglichen eine Korrektur dieses Fehlers, wenn die Temperatur in der Zentrifuge bekannt ist. l IntroductionDuring the performance of experiments on the density of erythrocytes of babies in relation to a suspected risk for sudden infant death syndrome (SIDS) [3] we became aware of the following problem. The population of erythrocytes in the blood shows some variability with respect to size, hemoglobin content and density. These variabilities can be characterized by the corresponding frequency distributions, the best known of which is the Price-Jones distribution of the erythrocyte sizes.In 1964 Danon and Marikovsky [2] described a simple method for the determination of the frequency distribution of the density of erythrocytes in blood. The method is based on the fact that a droplet of a test fluid in a microhematocrit tube would, after centrifugation, float exactly above the erythrocytes with higher density and below the ones with lower density than the density of the test fluid. Mixtures of phthalate esters are ideal test fluids since their density can ea...

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Section: Discussionmentioning

confidence: 96%

mentioning

confidence: 99%

On the Influence of Temperature on the Measurement of Density Distribution of Erythrocytes. Bedeutung der Temperatur für die Bestimmung der Dichteverteilung von Erythrocyten

Haidmayer¹,

Kenner²,

Hinghofer‐Szalkay³

1980

Biomedizinische Technik/Biomedical Engineering

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“…When data from all three Skylab samples were combined, the lymphocyte response was clearly suppressed on day of recovery, a transient effect that was restored to preflight level by day 1 of recovery. Again, the inhibitory role of cortisol-like hormones was suggested, which may have been induced by viral infections, radiation damage, noxious agents, and stresses of reentry in addition to the effects of weightlessness (Kimzey et al, 1975b).…”

Section: Lymphocyte Function and Countsmentioning

confidence: 99%

“…, with two exceptions (Criswell and Kimzey, 1977;Mukhina et al, 1980), indicate that many indices of immune function are decreased during prolonged bed rest and are perturbed as well during and after spaceflight (Barone and Caren, 1984;Cogoli, 1981;Kimzey, 1977;Kimzey et al, 1975aKimzey et al, , 1975b. Lack of proper controls and clean experimental designs have hampered definitive findings from spaceflight.…”

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confidence: 92%

Review

Greenleaf

Jackson

Lawless

1994

Sports Medicine, Training and Rehabilitation

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Immune responses measured at rest immediately or some hours after exercise training (some with and some without increase in maximal oxygen uptake) gave variable and sometimes conflicting results; therefore, no general conclusions can be drawn. On the other hand, most immune responses were either unchanged (immunoglobulin, T cells, CD4+, and natural killer activity) or decreased (blood properdin, neutrophil phagocytic activity, salivary lysozymes, brain immunoglobulin A and G, and liver B lymphocytes and phytohemagglutinin activity) during prolonged bed rest. Some data suggested that exercise training during bed rest may partially ameliorate the decreased functioning of the immune system. Exercise and change in body position, especially during prolonged bed rest with plasma fluid shifts and diuresis, may induce a change in plasma protein concentration and content, which can influence drug metabolism as well as immune function. Leukocytosis, accompanied by lymphopenia and a depressed lymphocyte response, occurs in astronauts on return to Earth from spaceflight; recovery may depend on time of exposure to microgravity. It is clear that the effect of drugs and exercise used as countermeasures for microgravity deconditioning should be evaluated for their effect on an astronaut's immune system to assure optimal health and performance on long-duration space missions.With the prospect of long-term spaceflight and the potential colonization of the Moon and Mars, the relative confinement and close contact of astronauts and the necessary limitation of medical treatment and facilities will focus more attention on preventive medicine in general, and also on overall functioning of the immune system. The adaptive physiologic deconditioning response of many body systems has been studied extensively during prolonged bed rest (Greenleaf et al., 1976(Greenleaf et al., , 1982Luu et al., 1990) and, to a lesser extent because of operational constraints, during spaceflight (Garshnek, 1989; Nicogossian etal., 1989). Immune system function has not been investigated extensively during exposure to prolonged bed rest or microgravity. Research findings (Chukhlovin and Burov, 1969;

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“…Red cell mass increased in chronically accelerated animals (8) and was decreased in astronauts post-flight (9). Bone mineralization was arrested in rats exposed to weightlessness (10); and loss of calcium from the body as well as thinning of the os calcis was reported in astronauts (ll, 12).…”

Section: The Concept Of Scale Effects In Animalsmentioning

confidence: 99%

The influence of gravity on structure and function of animals

Ross

1984

Advances in Space Research

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Gravity is the only environmental parameter that has remained constant during the period of evolution of living matter on Earth.Thus, it must have been a major force in shaping living things.The influence of gravitational loading on evolution of the vertebrate skeleton is well recognized, and scale effects have been studied. This paper, however, considers in addition four pivotal events in early evolution that would seem to have been significant for the later success and diversification of animal life. These are evolution of the cytoskeleton, cell motility (flagellae and cilia), gravity detecting devices (accelerometers), and biomineralization.All are functionally calcium dependent in eukaryotes and all occurred or were foreshadowed in prokaryotes.A major question is why calcium was selected as an ion of great importance to the structure and function of living matter; another is whether gravity played a role in its selection.

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Skylab experiment results: Hematology studies

Cited by 23 publications

References 3 publications

On the Influence of Temperature on the Measurement of Density Distribution of Erythrocytes. Bedeutung der Temperatur für die Bestimmung der Dichteverteilung von Erythrocyten

On the Influence of Temperature on the Measurement of Density Distribution of Erythrocytes. Bedeutung der Temperatur für die Bestimmung der Dichteverteilung von Erythrocyten

Review

The influence of gravity on structure and function of animals

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