{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T03:52:09Z","timestamp":1777866729950,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,10,6]],"date-time":"2009-10-06T00:00:00Z","timestamp":1254787200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,10,6]],"date-time":"2009-10-06T00:00:00Z","timestamp":1254787200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Dermatology"],"abstract":"<jats:p>Background: It is generally accepted that a UVA-induced erythema is difficult to detect except in the most sensitive individuals. Objective and Methods: As UVA effects on human skin and skin cells have been shown to depend strongly on anatomical body sites, UVA I, UVA I+ II and solar simulator radiations were compared in their ability to induce erythema and melanin pigmentation responses in individuals with skin types I\u2013IV on both previously sun-exposed (arms, forearms, thighs) and nonexposed body sites (buttocks). Results: Erythema induction by UVA I on previously nonexposed skin sites followed a dose response in all skin types which was contrary to the absence of erythema induction seen on previously sun-exposed sites. Melanin expression followed a dose and skin type response and was shown to be more enhanced in previously exposed skin and in skin types III and IV In contrast, UVA I + II induced erythema on nonexposed skin areas and to a lesser extent on frequently sun-exposed skin. Melanin production by UVA I + II was similar to that seen with UVA I alone in individuals of skin types II and III. Solar simulator radiation was very efficient in erythema induction regardless of previous sun exposure of skin. Conclusions: We have found that contrary to the widespread opinion that UVA and in particular UVA I could not induce a significant erythema, this waveband is capable of measurable erythema induction on skin nonexposed to sunlight. The diminished erythema induction by UVA I on chronically sun-exposed skin suggests the possibility of a defense mechanism against UVA-induced damage in this tissue.<\/jats:p>","DOI":"10.1159\/000246055","type":"journal-article","created":{"date-parts":[[2009,10,7]],"date-time":"2009-10-07T07:08:20Z","timestamp":1254899300000},"page":"41-49","source":"Crossref","is-referenced-by-count":7,"title":["Erythema Induction by Ultraviolet Radiation Points to a Possible Acquired Defense Mechanism in Chronically Sun-Exposed Human Skin"],"prefix":"10.1159","author":[{"given":"L.A.","family":"Applegate","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"C.","family":"Scaletta","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G.","family":"Treina","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"R.E.","family":"Mascotto","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A.","family":"Fourtanier","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"E.","family":"Frenk","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2009,10,6]]},"container-title":["Dermatology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/246055","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000246055","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T09:13:06Z","timestamp":1777540386000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000246055"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,10,6]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000246055","archive":["Portico"],"relation":{},"ISSN":["1018-8665","1421-9832"],"issn-type":[{"value":"1018-8665","type":"print"},{"value":"1421-9832","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,10,6]]}}}