Asymmetric cell division of stem and progenitor cells during homeostasis and cancer

Stem and progenitor cells are characterized by their ability to self-renew and produce differentiated progeny. A fine balance between these processes is achieved through controlled asymmetric divisions and is necessary to generate cellular diversity during development and to maintain adult tissue homeostasis. Disruption of this balance may result in premature depletion of the stem/progenitor cell pool, or abnormal growth. In many tissues, including the brain, dysregulated asymmetric divisions are associated with cancer. Whether there is a causal relationship between asymmetric cell division defects and cancer initiation is as yet not known. Here, we review the cellular and molecular mechanisms that regulate asymmetric cell divisions in the neural lineage and discuss the potential connections between this regulatory machinery and cancer.     

Levamisole inhibits mineral mobilisation, lactate production and lysosomal enzyme release from cultured bones.

Levamisole added to cultured calvarial bones inhibited spontaneous bone resorption, as indicated by reduced release of calcium and inorganic phosphate to the medium. In addition, levamisole reduced lactate production and release of lysosomal enzymes.     

Multiple neutral amino acid transport systems in chicken small intestine: Evidence for a separate proline transfer agency

Zusammenfassung Die Darmresorption von Prolin, Alanin,-Alanin, Sarkosin und Taurin bei Hühnern wurde in vitro untersucht und ein spezielles Resorptions-system für Prolin beschrieben.

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This investigation was supported by a grant fromthe Maine Agricultural Experiment Station (Hatch Project No. 880-H241). Part of this work was taken from the Ph. D. thesis of P.B.     

Antiproliferative effects of 4',5'-unsaturated adenine nucleosides on leukemia L1210 cells in vitro

Several 4',5'-unsaturated adenine nucleosides were shown to have antiproliferative activity against L1210 leukemia cells in vitro. The active nucleosides were cytotoxic to the L1210 cells as demonstrated by Trypan Blue uptake. The cytotoxicity was not induced by alterations in the ribonucleoside and deoxyribonucleoside triphosphate levels of the L1210 cells.     

Antiproliferative effects of 4′, 5′-unsaturated adenine nucleosides on leukemia L 1210 cells in vitro

Summary Several 4, 5-unsaturated adenine nucleosides were shown to have antiproliferative activity against L 1210 leukemia cells in vitro. The active nucleosides were cytotoxic to the L 1210 cells as demonstrated by Trypan Blue uptake. The cytotoxicity was not induced by alterations in the ribonucleoside and deoxyribonucleoside triphosphate levels of the L 1210 cells.     

Levamisole inhibits mineral mobilisation,lactate production and lysosomal enzyme release from cultured bones

Summary Levamisole added to cultured calvarial bones inhibited spontaneous bone resorption, as indicated by reduced release of calcium and inorganic phosphate to the medium. In addition, levamisole reduced lactate production and release of lysosomal enzymes.     

Determination and statistical comparisons of Michaelis-Menten kinetic parameters

Summary A method is described for determining and statistically comparing Michaelis-Menten kinetic parameters.This work was supported in part by a U.S.P.H.S. Grant No. AM 15745 from the National Institute of Arthritis, Metabolism and Digestive Diseases and by the Maine State Agricultural Experiment Station.