Ultraviolet Damage and Repair Flashcards
The UV-B radiation (about 0.5% of the solar radiation) is responsible for most of the effects of sunlight on the body. It is the main cause of ____, as well as the formation of _____in the skin, and it influences the ____.
sunburn and tanning; vitamin D3; immune system
UVR induces the non-enzymatic synthesis of ____ (VitD3) and _____ (VitD2).
cholecalciferol; ergocalciferol
_____ are converted to the active form in liver and kidney.
Both VitD3 and vitD2
____ causes premature aging, loose skin, wrinkles and dark patches, as well as DNA damage.
UVA
_____ (about 0.5% of the solar radiation) is responsible for most of the effects of sunlight on the body. It is the main cause of sunburn and tanning, as well as the formation of vitamin D3 in the skin, and it influences the immune system.
UV-B radiation
UVR damage to skin includes which 5 effects?
1) damage to DNA, RNA, lipids and proteins, 2) pro-inflammatory effects, 3) Immunosuppressive effects, 3) induction of innate defenses, 4) induction of apoptosis, 5) Vitamin D synthesis.
The main types of DNA damage resulting from UVR are:
-Thymine dimer (cyclobutane pyrimidine dimer) (UVB) -Pyrimidine-6-4 pyrimidone (UVB) -Hydroxyguanosine (UVA and singlet oxygen)
What cancers are caused by UVR?
Melanoma Non-melanoma Skin Cancer Basal Cell Carcinoma Squamous Cell Carcinoma
_____ contain VitD3 and vitD2.
Dietary supplements
What are the Skin Defenses Against UVR?
-DNA Repair -Apoptosis of Cells with DNA Damage -Defenses Against Reactive Oxygen -Melanin
The UV spectrum is divided into ____, ____, and ____ radiation.
UV-C (100 - 280 nm), UV-B (280 - 320 nm), and UV-A (320 - 400 nm)
UVR induces the non-enzymatic synthesis of cholecalciferol (____) and ergocalciferol (____).
VitD3; VitD2
Both VitD3 and vitD2 are converted to active form in the ____.
liver and kidney
Dietary supplements contain ____.
VitD3 and vitD2
Proteins involved in recognition of DNA damage?
XPC
