Survey of dermatologists' phototherapy practices for vitiligo.

Background: The details of phototherapy practices for vitiligo have been rarely studied. Objective: To explore the details of phototherapy practices for vitiligo among dermatologists. Methods: A self-administered questionnaire about the details of phototherapy practices for vitiligo was distributed to all dermatologists attending a national general dermatology conference in Riyadh, Saudi Arabia, in 2008. Results: Questionnaires were returned by 121 of 140 participants (response rate = 86.4%). The mean age of the respondents was 39.34 ΁ 9.7 years, and 65% were males. One hundred eight of 110 (98.2%) respondents provided phototherapy to their vitiligo patients. The mean number of vitiligo patients who underwent phototherapy each week per dermatologist's office was 18 ΁ 2.26. Narrowband ultraviolet B (NB-UVB) was the most common modality chosen to treat generalized vitiligo (84%). Excimer laser was the most common modality used to treat focal and segmental vitiligo (53% and 39%, respectively). Sixty-eight percent of dermatologists administered a fixed starting dose of NB-UVB to all patients, whereas 31% used the minimal erythema dose as a guide. Fifty percent reported that NB-UVB resulted in better color matching with the surrounding skin. Thirty-seven percent favored NB-UVB over psoralen + ultraviolet A for a faster response, and 31% preferred NB-UVB for a pigmentation that is more durable. Forty-seven percent (50/106) of the respondents limited the number of phototherapy sessions to reduce the risks of skin cancer. However, no respondent reported any skin cancer incidence in phototherapy-treated vitiligo patients. Conclusion: There is a need for phototherapy guidelines for the treatment of vitiligo in patients with skin of color.

Metabolismo lipídico na cultura de queratinócitos / Lipid metabolism in cultured keratinocytes

Os lipídios epidérmicos equivalem à quota de 10 a 14 por cento peso seco da epiderme dos mamíferos. Durante a queratinização, a composição e a quantidade dos lipídios epidérmicos mudam da camada basal para a granular na dependência de diferentes moduladores, até que, no extrato córneo, as células se organizam envolvidas em membranas bilamelares lipídicas, que parecem constituir relevante barreira funcional. O uso da cultura de queratinócitos tem contribuído para os estudos dos processos envolvendo a regulação da lipogênese na epiderme humana. A presente revisão propõe-se a mostrar a comparação da composição lipídica in vivo e ex vivo