Cell growth accelerating phase

Imatinib is a protein-tyrosine-kinase inhibitor. Imatinib inhibits proliferation and induces apoptosis in BCR-ABL positive cell lines as well as fresh leukemic cells from Philadelphia chromosome-positive (Ph-r) chronic myeloid leukemia (CML). Imatinib inhibits tumor growth of BCR-ABL transfected murine myeloid cells and BCR-ABL positive leukemia lines derived from CML patients in blast crisis. It also inhibits the receptor tyrosine kinases for platelet-derived growth factor (PDGF) and stem cell factor (SCF), c-Kit, and inhibits PDGF- and SCF-mediated cellular events. It is indicated in the treatment of newly diagnosed adult patients with Ph-t CML in chronic phase patients with Ph-t CML in blast crisis, accelerated phase, or in chronic phase after failure of interferon-alpha treatment children with Ph-t chronic phase CML whose disease has recurred after stem cell transplant or who are resistant to interferon-alpha therapy and treatment of gastrointestinal stromal tumors (GIST). 

During the acceleration phase, biosynthesis of some constituents of the cytoplasm takes place to allow the cells of the organism to adjust in response to the transition from the original environment of the inoculum to that of the growth medium. In effect, the organisms are either... 

Microorganisms enter the exponential phase having utihzed the acceleration phase to make the adjustments in their biological machinery and metabolic pathways that are necessary for them to multiply rapidly in the growth medium. The number of cells present in the reactor increases at a rate that is first-order in the number of cells present ... 

Accelerated growth phase The cell number starts to increase and the division rate increases to reach a maximum. 

It should be noted that Eq. (6.21) only applies when rx is larger than zero. Therefore, t1 in Eq. (6.21) is not the time that the culture was inoculated, but the time that the cells start to grow, which is the beginning of the accelerated growth phase. 

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