Log kill

The photodynamic effect of chloroaluminum(III) phthalocyanine ((47), with C1A1 in place of Zn), a commercial product, was reported by Ben-Hur and Rosenthal.302 The photosensitizer was delivered in ethanol to cultures of Chinese hamster fibroblasts. After equilibration (16 h), exposure to visible light (fluence rate 64 Wm-2) of a suspension in PBS for 2 min gave a 3 log kill. Lack of water solubility is a problem, and for in vivo PDT of EMT-6 mammary tumors in mice a Cremophor emulsion was employed.303 The compound was a more effective PDT sensitizer than... 

The cell-kill hypothesis states that the effects of antitumor drugs on tumor cell populations follow first-order kinetics. This means that the number of cells killed is proportional to the dose. Thus, chemotherapy follows an exponential or log-kill model in which a constant proportion, not a constant number, of cancer cells are killed. Ilieoretically. the fractional reductions possible with cancer chemotherapy can never reduce tumor populations to zero. Complete er ica-tion requires another effect, such as the immune response. A modified form of the first-order log-kill hypothesis holds that tumor regressions produced by chemotherapy are de-.scribed by the relative growth fraction present in the tumor at the lime of treatment This idea is consistent with the finding that very small and very large tumors are less responsive than tumors of intermediate size. ... 

The "log-kill" hypothesis states that cytotoxic anticancer agents kill a certain percentage, not a fixed number, of cells. 

Log-kill hypothesis A concept used in cancer chemotherapy to mean that anticancer drugs kill a fixed proportion of a tumor cell population, not a fixed number of tumor cells. For example, a 1-log-kill will decrease a tumor cell population by one order of magnitude, ie, 90% of the cells will be eradicated... 

In a patient with diffuse lymphoma, the oncologist suggests a treatment strategy that involves the initial administration of doxorubicin to obtain a significant log-kill, followed by the cell cycle-specific drugs cytarabine and vincristine. This therapeutic strategy is called... 

Recruitment strategy in cancer chemotherapy involves the initial use of a CCNS drug (eg, doxorubicin) to achieve a significant log kill. This results in the recruitment into cell division of resting... 

Sporicidin (glutaraldehyde plus phenol plus phenate) achieved a 6-log kill... 

Entry Product m n Yield (%) MIC (mmol/L) Log kill Xpscd ... 

From this we see that Garner s activation energy Eq is complex. The first term in (27) shows that it bears no simple relationship to the activation energies, E /( n) == kT ld log kfiq jdT], of the elementary processes of kinetic unit transformation in the forward direction. The second term shows that Eq bears no simple relationship to the heat of dissociation, kT ld log p jdT], but also involves the heats of the vacancy equilibria, kT ldXog KJdT] and kT [d log Kill dT]. It is understandable that the experimental values of... 

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