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C W Orr

Publications and source records attributed to C W Orr.

9 recordsLinked to original sources
PubMed1972

Potassium: effect on DNA synthesis and multiplication of baby-hamster kidney cells: (cell cycle-membrane potential-synchronization-transformation).

The relations between DNA synthesis, cell multiplication, and external potassium concentration have been investigated in cultured baby-hamster kidney cells. When the potassium concentration was raised from 8 mM to 114 mM by equimolar replacement of sodium, DNA synthesis and cell multiplication were almost completely inhibited. This inhibition was reversible even after 72 hr of incubation in medium with a high concentration of potassium. There is a consistent difference between the cultured cells and polyoma virus-transformed cells in response to high-potassium medium, a higher-potassium concentration being required to inhibit multiplication of polyoma virus-transformed cells to the same extent as that of the nontransformed cells.

Animals↗
PubMed1969

An L-glutamine requirement for intercellular adhesion.

Intercellular adhesion presumably involves components of the cell surface, but the chemical nature of these substances is not known. The present studies suggest that complex carbohydrates are required for the adhesion of at least one type of animal cell. Single cells obtained from "embryoid bodies," the ascites-grown form of a mouse teratoma, aggregated in a complex tissue culture medium, but not in a glucose balanced salts solution. The active component of the tissue culture medium was identified as L-glutamine, and the only compounds found to replace it were the hexosamines D-glucosamine and D-mannosamine. A variety of studies indicated that the three compounds were active as a consequence of metabolic reactions. These results are consistent with known metabolic pathways and indicate that the conversion of nonadhesive to adhesive teratoma cells requires the synthesis of glycoproteins, glycolipids, and/or polysaccharides.

Adhesiveness↗