000019 Letter to the Editor Hoffmann Hoffmann Gerd G Prof. Dr. med.

Johann Wolfgang Goethe University, Institute of Sports Sciences, Ginnheimer Landstraße 39, 60487 Frankfurt/Main, Germany, Tel.+Fax+Q: 0049-6181-62287Johann Wolfgang Goethe University, Institute of Sports Sciences, Frankfurt/Main, Germany

Hoffmann@em.uni-frankfurt.de author Meffert Meffert Hans H Prof. Dr. med.

University Hospital Charité, Campus Charité Mitte, Medical Faculty of the Humboldt University Berlin, Clinic of Dermatology, Venereology and Allergology, Department of Photodermatology, Schumannstraße 20/21, 10117 Berlin, GermanyUniversity Hospital Charité, Campus Charité Mitte, Medical Faculty of the Humboldt University Berlin, Clinic of Dermatology, Venereology and Allergology, Department of Photodermatology, Berlin, Germany

Hans.Meffert@web.de author German Medical Science

Düsseldorf, Köln

610 20050225 20050304 20090114 engl 1612-3174 3 GMS German Medical Science GMS Ger Med Sci 01 20090113Orthographic corrections Text We would like to comment on the three contributions in the Journal of the National Cancer Institute, Vol. 97, No. 3, February 2, 2005: · Kathleen M. Egan, Jeffrey A. Sosman, William J. Blot: Editorial: Sunlight and Reduced Risk of Cancer: Is the Real Story Vitamin D? (pp. 161-163) · Marianne Berwick, Bruce K. Armstrong, Leah Ben-Porat, Judith Fine, Anne Kricker, Carey Eberle, Raymond Barnhill: Sun Exposure and Mortality From Melanoma. (pp. 195-199) · Karin Ekström Smedby, Henrik Hjalgrim, Mads Melbye, Anna Torrång, Klaus Rostgaard, Lars Munksgaard, et al.: Ultraviolet Radiation Exposure and Risk of Malignant Lymphomas. (pp. 199-209) The apparent contradiction between the well known negative effects of UV radiation on humans and the newly described positive effects of sun exposure (like reduced risk of cancer) is easily solved, when taking into account, that sun exposure ("sunlight") consists of at least three biologically active parts of radiation: ultraviolet radiation (UV), visible light (VIS) und infrared (IR). Especially infrared-A (780-1400 nm) with adequate irradiation intensity has been shown not only to be harmless to human skin , but to have protective abilities against damage caused by UV radiation , ! In moderate climatic zones, sun radiation is filtered by water vapor in the atmosphere before reaching the surface of the earth, by this decreasing infrared-C, infrared-B and the absorption bands within infrared-A, leaving a large amount of water-filtered infrared-A (wIRA) with good penetration properties into skin and without bringing much thermal burden to the surface of the skin . Infrared-A, especially water-filtered infrared-A, is able to increase tissue temperature, tissue perfusion and tissue oxygen partial pressure , : these three thermal effects are prerequisites of a high energy production in tissue and can therefore improve energy dependent immunologic reactions. Beside this, wavelengths within infrared-A, especially near to visible light (approximately 780-1000 nm), have been shown to stimulate cells in a positive manner even with very low irradiation intensities (below intensities with thermal effects) , , , . In addition, sunlight includes high irradiation intensities of all five absorption bands of protoporphyrin IX (approxi-mately 406 nm, 505 nm, 540 nm, 574 nm, 629 nm ), which can react with endogenously formed protoporphyrin IX with and without oxygen in photooxidative reactions (type I and type II), giving a mild form of a photodynamic therapy (PDT), being able to modulate the immune system or to bring damaged cells to apoptosis , . Furthermore, it is well known that modalities of UV irradiation, like its dose, increase, quality and the frequency of applications, are of crucial importance whether wanted or unwanted effects will take place. With a given daily sun exposure of less than .3 Minimal Erythema Doses (MED) vitamin D status is sufficient in babies. We calculated a simple diagram which shows how to get .3 MED at different times of the day and different seasons . As a minor remark: Although the main statements of the publications of Berwick and Smedby will most likely be unchanged, both publications miss an alpha error adjustment, which is necessary in cases of multiple testing and which typically leads to a marked decrease in the number of significant differences or effects, when large numbers of tests are done. Egan KM Sosman JA Blot WJ Sunlight and reduced risk of cancer: is the real story vitamin D? J Natl Cancer Inst. 2005 Egan KM, Sosman JA, Blot WJ. Sunlight and reduced risk of cancer: is the real story vitamin D? J Natl Cancer Inst. 2005;97(3):161-3. Berwick M Armstrong BK Ben-Porat L Fine J Kricker A Eberle C Barnhill R Sun exposure and mortality from melanoma 2005 J Natl Cancer Inst 195-9 Berwick M, Armstrong BK, Ben-Porat L, Fine J, Kricker A, Eberle C, Barnhill R. Sun exposure and mortality from melanoma. J Natl Cancer Inst. 2005;97(3):195-9. Smedby KE Hjalgrim H Melbye M Torrång A Rostgaard K Munksgaard L Adami J Hansen M Porwit-MacDonald A Jensen BA Roos G Pedersen BB Sundstrom C Glimelius B Adami HO Ultraviolet radiation exposure and risk of malignant lymphomas 2005 J Natl Cancer Inst 199-209 Smedby KE, Hjalgrim H, Melbye M, Torrång A, Rostgaard K, Munksgaard L, Adami J, Hansen M, Porwit-MacDonald A, Jensen BA, Roos G, Pedersen BB, Sundstrom C, Glimelius B, Adami HO. Ultraviolet radiation exposure and risk of malignant lymphomas. J Natl Cancer Inst. 2005;97(3):199-209. Burri N Gebbers N Applegate LA Chronic infrared-A radiation repair: Implications in cellular senescence and extracellular matrix 2004 Recent Research Developments in Photochemistry & Photobiology 219-31 81-7895-129-0 Burri N, Gebbers N, Applegate LA. Chronic infrared-A radiation repair: Implications in cellular senescence and extracellular matrix. In: Pandalai SG, ed. Recent Research Developments in Photochemistry & Photobiology, vol. 7. Trivandrum: Transworld Research Network; 2004. p. 219-31. Menezes S Coulomb B Lebreton C Dubertret L Non-coherent near infrared radiation protects normal human dermal fibroblasts from solar ultraviolet toxicity 1998 J Invest Dermatol 629-33 Menezes S, Coulomb B, Lebreton C, Dubertret L. Non-coherent near infrared radiation protects normal human dermal fibroblasts from solar ultraviolet toxicity. J Invest Dermatol. 1998;111(4):629-33. Applegate LA Scaletta C Panizzon R Frenk E Hohlfeld P Schwarzkopf S Induction of the putative protective protein ferritin by infrared radiation: implications in skin repair 2000 Int J Mol Med 247-51 Applegate LA, Scaletta C, Panizzon R, Frenk E, Hohlfeld P, Schwarzkopf S. Induction of the putative protective protein ferritin by infrared radiation: implications in skin repair. Int J Mol Med. 2000;5(3):247-51. Fuchs SM Fluhr JW Bankova L Tittelbach J Hoffmann G Elsner P Photodynamic therapy (PDT) and waterfiltered infrared A (wIRA) in patients with recalcitrant common hand and foot warts 2004 Ger Med Sci Doc08 Fuchs SM, Fluhr JW, Bankova L, Tittelbach J, Hoffmann G, Elsner P. Photodynamic therapy (PDT) and waterfiltered infrared A (wIRA) in patients with recalcitrant common hand and foot warts. Ger Med Sci 2004;2:Doc08. Available from: http://www.egms.de/en/gms/2004-2/000018.shtml (shtml), http://www.egms.de/pdf/gms/2004-2/000018.pdf (PDF) Vaupel P Krüger W eds 1995 Wärmetherapie mit wassergefilterter Infrarot-A-Strahlung Vaupel P, Krüger W, eds. Wärmetherapie mit wassergefilterter Infrarot-A-Strahlung [Thermal therapy with water-filtered infrared-A radiation]. 2nd ed. Stuttgart: Hippokrates; 1995. Albrecht-Buehler G Surface extensions of 3T3 cells towards distant infrared light sources 1991 J Cell Biol 493-502 Albrecht-Buehler G. Surface extensions of 3T3 cells towards distant infrared light sources. J Cell Biol. 1991;114(3):493-502. Karu TI Primary and secondary mechanisms of action of visible to near-IR radiation on cells [review] 1999 J Photochem Photobiol B 1-17 Karu TI. Primary and secondary mechanisms of action of visible to near-IR radiation on cells [review]. J Photochem Photobiol B. 1999;49(1):1-17. Karu TI Pyatibrat LV Kalendo GS Cell attachment to extracellular matrices is modulated by pulsed radiation at 820 nm and chemicals that modify the activity of enzymes in the plasma membrane 2001 Lasers Surg Med 274-81 Karu TI, Pyatibrat LV, Kalendo GS. Cell attachment to extracellular matrices is modulated by pulsed radiation at 820 nm and chemicals that modify the activity of enzymes in the plasma membrane. Lasers Surg Med. 2001;29(3):274-81. Ehrlicher A Betz T Stuhrmann B Koch D Milner V Raizen MG Käs J Guiding neuronal growth with light 2002 Proc Natl Acad Sci USA doi:10.1073/pnas.252631899. Ehrlicher A, Betz T, Stuhrmann B, Koch D, Milner V, Raizen MG, Käs J. Guiding neuronal growth with light. Proc Natl Acad Sci USA. 2002;99(25):16024-8. doi:10.1073/pnas.252631899. Ackermann G 2001 Photophysikalische Grundlagen zur Fluoreszenzdiagnostik von Tumoren der Haut [Thesis] [Photophysical fundamentals of fluorescence diagnosis of skin tumors] Ackermann G. Photophysikalische Grundlagen zur Fluoreszenzdiagnostik von Tumoren der Haut [Thesis] [Photophysical fundamentals of fluorescence diagnosis of skin tumors]. Regensburg: University Regensburg; 2001. Available from: http://www.bibliothek.uni-regensburg.de/opus/volltexte/2001/27/ Siafarikas A Piazena H Hesse V Meffert H Importance of solar UV exposures to prevent rickets by supporting vitamin D production in the skin of babies (first results) 2001 2nd Euroskin Conference, Orvieto, Italy, October 1-5, 2001 Siafarikas A, Piazena H, Hesse V, Meffert H. Importance of solar UV exposures to prevent rickets by supporting vitamin D production in the skin of babies (first results). 2nd Euroskin Conference, Orvieto, Italy, October 1-5, 2001. 0 0 0 0