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U Reincke

Publications and source records attributed to U Reincke.

31 records · Page 2Linked to original sources
PubMed1976

Volumes and cellularity in populations of hematopoietic clones.

Volumes of hematopoietic spleen colonies were estimated by measuring parameters of superimposed triaxial ellipsoids. Observations were made on groups of colonies that contained only undifferentiated cells or had differentiated to varying degrees into purely erythropoietic, purely granulocytic or purely megakaryocytic colonies. The average volume occupied by one cell and surrounding matrix, the so-called single cell space, was determined for each type of colony. The estimated colony cellularity was then computed from the measured colony volume and the tabulated single cell space. The techniques of measurement are described. Formulas are provided to estimate mean and variance of volumes and their cell contents. Data on the distribution of spleen colony size and cellularity after seven days of growth are given.

Animals↗
PubMed1975

Hayflick's hypothesis: an approach to in vivo testing.

The experimental evidence relating to the hypothesis of finite cellular life is reviewed. It is emphasized that even if somatic cell production were limited its total potential would have to be vast to provide for extensive cellular regeneration. The actual limit of reproductive cell life would therefore not likely be reached in a normal life-span. It is proposed to test the hypothesis by deliberate exhaustion of stem-cell reserve, and iron-55 cytocide is described as an experimental system that might be applicable.

Animals↗
PubMed1975

Selective damage to erythroblasts by 55-Fe.

The low energy and short range of 55-Fe Auger electrons were utilized in mice to deliver lethal intracellular radiation to iron-incorporating erythropoietic precursors with minimal radiation damage to other bone marrow cells. The ensuing intramedullary, selective erythropoietic death was demonstrated by absolute and differential bone marrow cell counts and by decreased blood uptake of 59-Fe. The decreased number of colony-forming units in spleen colony assay and the decreased ability of tranplanted bone marrow to protect fatally irradiated mice shows that the bone marrow was partially depleted of pluripotent stem cells. These data are interpreted to indicate an increased pluripotent stem cell utilization in response to increased demand for differentiation of stem cells along the erythropoietic pathway.

Animals↗
PubMed1972

Erythropoietin production in cultures of goat renal glomeruli.

Cultures initiated with isolated goat-kidney glomeruli produce erythropoietin over periods of 7 months. Production seems dependent upon a minimum interval of about 30 days between changes of medium. Experiments distinguishing between erythropoietin, renal activator, and serum substrate support the conclusion that the factor released to the medium of long-term glomerular cultures is erythropoietin itself. The system offers promising opportunities for studying regulation of erythropoietin production, and possibly could be developed as a source of significant quantities of the hormone.

Animals↗