solar radiation and sunscreen and Vitamin D

Question 1

What are the markers for UVB DNA damage?

Answer 1

CPDs and 6,4 photoproducts

Question 2

What are the markers for UVA damage?

Answer 2

DNA adducts, adduct 8-oxoG= 8-hydroxyguanosine

Question 3

What type of damage does UVB induce? What is the optimal wavelength for damage?

Answer 3

Direct DNA damage, causes pyrimidine dimers. 300nm is most efficient.

Question 4

How does UVA induce DNA damage?

Answer 4

1. chromophore absorbs UVA and causes strand breaks

2. Lipids absorb UVA and MDA bonds with guanosine

Question 5

What are the criteria for a sunscreen to be broad spectrum?

Answer 5

Critical wavelength > 370nm and SPF>15 to be broad spectrum

Question 6

What are the recommended Vitamin D levels?

Answer 6

• 20ng/mL serum levels of 25 OHD

- 600IU/day for children and adults, higher for seniors, lower for infants