الفهرس 
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Abstract
Non-coherent infrared (IR) hyperthermia using a light fluence rate of 160 mW/cm² to produce a temperature of 40°C or 42°C with different exposure times i.e. 5 , 10 and 20 minutes, was used to examine the effect of this type of hyperthermia on human hepatocellular carcinoma cells (HepG2). Adriamycin (doxorubicin) was also used separately to detect the effect of this chemotherapeutic agent on the same cell line. On the basis of the cell survival data obtained after conducting a pilot study with different concentrations of adriamycin (ranging between 0.5 & 10 µg/ml) the concentrations of 1, 2.5 & 5 µg/ml were selected to carry out the experiments in the present study. The effect of combined chemotherapy and hyperthermia (thermochemotherapy) was studied. The results indicated that hyperthermia at 40°C or 42°C when used alone had a significant reducing effect on cell survival as the time of exposure to hyperthermia increased from 5 to 20 minutes. The administration of adriamycin alone also showed a significant decrease in the survival of HepG2 cells as the concentration of the drug increased. The combined therapy of hyperthermia and adriamycin showed a significant synergistic effect on the survival of HepG2 cells. The decrease in the survival observed with this combined therapy was significantly more than that obtained by either hyperthermia or adriamycin alone. The uptake of adriamycin in HepG2 cells was assessed as a function of adriamycin concentration, hyperthermia and exposure time to hyperthermia. The results indicted that hyperthermia increased significantly the uptake of adriamycin by HepG2 cells. In addition, increasing the exposure time to hyperthermia increased the uptake of the drug. Malondialdehyde assay was used as an index of cell membrane lipid peroxidation. The combined therapy of adriamycin and hyperthermia at 40 °C for 20 minutes exposure increased significantly malondialdehyde production in HepG2 cells compared to those treated with adriamycin or hyperthermia alone for different time intervals. Light microscope images and ultrastructural studies using transmission electron microscopy indicated that the use of adriamycin (5µg/ml) alone was more effective compared to the use of hyperthermia alone in inducing early cell death (apoptosis). The combined therapy showed a significantly higher increase in cell apoptosis percentage, compared to that obtained when hyperthermia or adriamycin were used alone. The results obtained from this study indicated that there was a clear synergistic effect when chemotherapy was used compared to chemotherapy or hyperthermia alone.