1 / 20

EFFECTS OF ULTRAVIOLET RADIATION

EFFECTS OF ULTRAVIOLET RADIATION. Henry W. Lim, MD Co-Chair National Council on Skin Cancer Prevention. PRESENTER. Chairman, Department of Dermatology, Henry Ford Hospital, Detroit, MI Photodermatology. DISCLOSURE.

kalyca
Télécharger la présentation

EFFECTS OF ULTRAVIOLET RADIATION

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. EFFECTS OF ULTRAVIOLET RADIATION Henry W. Lim, MD Co-Chair National Council on Skin Cancer Prevention

  2. PRESENTER • Chairman, Department of Dermatology, Henry Ford Hospital, Detroit, MI • Photodermatology

  3. DISCLOSURE • Consultant : La Roche-Posay/L’Oreal, Orfagen, Dow Pharmaceutical Sciences • Investigator: Johnson & Johnson

  4. ELECTROMAGNETIC RADIATION

  5. ULTRAVIOLET RADIATION UV λ (nm) Properties UVC 200-290 Germicidal UVB 290-320 Sunburn UVA 320-400 Pigment darkening, tanning

  6. EFFECTS OF UV • DNA damage • Erythema • Tanning • Vitamin D synthesis • Immunosuppression • Skin cancer

  7. EFFECTS OF UV • DNA damage

  8. UV AND DNA DAMAGE UVB: • Direct effect • Cyclobutane-pyrimidine dimers Bolognia, et al. Dermatology. 2008

  9. UV AND DNA DAMAGE(Agar NS, PNAS 4/04; 101:4954; Budiyanto A, P&P10/02; 76:397) UVA: • Indirect mechanism • Absorption by skin chromophores → reactive oxygen species → reacts with guanine → oxidative products (8-oxoG, 8-oxo-dG) • Mutagenic

  10. EFFECTS OF UV • DNA damage • Erythema

  11. ERYTHEMA • Primarily the effect of UVB • Peaks at 24 hrs

  12. EFFECTS OF UV • DNA damage • Erythema • Tanning

  13. MECHANISMS OF TANNING(Hönigsmann H, PPP 4/02; 18:75) • UV: activation of tyrosinase • UV  DNA damage  nucleotide fragments excised in repair  stimulate melanogenesis

  14. ERYTHEMA & TANNING • UVB: Erythema > tanning • UVA: Tanning > erythema • Tanning is an indication that DNA damage has occurred • There is no “safe tan”

  15. EFFECTS OF UV • DNA damage • Erythema • Tanning • Vitamin D synthesis • Action spectrum: UVB

  16. EFFECTS OF UV • DNA damage • Erythema • Tanning • Vitamin D synthesis • Immunosuppression • Skin cancer

  17. UV: IMMUNOSUPPRESSION AND SKIN CANCER(International Agency for Research on Cancer Working Group on artificial ultraviolet light and skin cancer. Green A, et al. Int J Cancer 3/07; 120:1116) • UV: immunosuppressive • Chronic UV exposure: • Photoaging changes • Squamous cell carcinoma • Basal cell carcinoma • Tanning bed users: • Melanoma • Squamous cell carcinoma

  18. NATURAL AND ARTIFICIAL UV • DNA damage, immunosuppression, skin cancer • WHO: UV is carcinogen • WHO: UV tanning beds: “carcinogenic to humans.” (El Ghissassi F, Lancet Oncol 7/09; 10: 751)

  19. NCSCP RECOMMENDATIONS • To reclassify sunlamps for tanning as Class II devices • To impose special controls: user labeling and user registry • To prohibit use by consumers younger than 18 years • To require license for facilities at which sunlamps may be used • To have training and certification of operators

  20. www.skincancerprevention.org

More Related