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Biomedical subjects

I Watanabe

Publications and source records attributed to I Watanabe.

At least 739 records · Page 41Linked to original sources
PubMed1967

Effects of temperature on growth rate of cultured mammalian cells (L5178Y).

L5178Y cells were cultured in vitro at various temperatures. When the cells were in the exponential growth phase, the cells were in the "steady state of growth," i.e., the fraction of cells in the G(1), S, G(2), and M stages and the durations of each stage were constant. The life cycle analysis of the cells in the steady state of growth demonstrated that the G(1) stage and the S stage were affected the most by variation of temperature, and suggested that these two stages have considerable influence on the growth rate of the L5178Y cells. The calculated activation energies were positive in each stage of the life cycle, whereas the entropies of activation were negative throughout. The possible significance of these findings in our search for the regulatory mechanisms of cell growth is discussed.

Animals↗
PubMed1967

Stationary phase of cultured mammalian cells (L5178Y).

The stationary phase of the mammalian cells L5178Y in culture can be divided into two stages: (a) an early phase characterized by the decline of mitotic index, followed by a stabilization of the cell number, and (b) a late stage, occurring several hours after the flattening of the growth curve, during which dead or dying cells appear in the cultures. The estimates of rates of cell progress showed that the rates from G(1) to S and from G(2) to M were affected in the early stationary phase. The main cause of cessation of increase in cell number in the early stationary phase is resulted from the decline in mitotic index, which is caused by prolongation of the G(2) period. The importance of the G(2) stage in regulating the cell growth is discussed in relation to other known situations in the literature.

Animals↗