UVB Light Source and Irradiation of Mice
The dorsal skin of mice was shaved using clippers before exposure to UVB radiation. UVB (200 mJ/cm2) was administered per day, three days per week, from a bank of four UVB lamps (Daavlin, UVA/UVB Research Irradiation Unit, Bryan, OH). The irradiation unit was equipped with an electronic controller to regulate UVB dosage at the fixed distance of 24 cm from the lamps to the dorsal skin surface of the mice. Wavelengths 1 mm in diameter, that persisted for at least 2 weeks, were defined as tumors and recorded. Mice that were not exposed to UVB radiation were used as controls in all experiments.
The dorsal skin of mice was shaved using clippers before exposure to UVB radiation. UVB (200 mJ/cm2) was administered per day, three days per week, from a bank of four UVB lamps (Daavlin, UVA/UVB Research Irradiation Unit, Bryan, OH). The irradiation unit was equipped with an electronic controller to regulate UVB dosage at the fixed distance of 24 cm from the lamps to the dorsal skin surface of the mice. Wavelengths 1 mm in diameter, that persisted for at least 2 weeks, were defined as tumors and recorded. Mice that were not exposed to UVB radiation were used as controls in all experiments.