Research Snippets

        Repeated exposure to hair dye induces regulatory T cells in mice

        Rubin et al. studied how exposure to p-phenylenediamine (PPD)-containing hair dye, in a consumer-like fashion, affected pro- and anti-inflammatory immune responses in a mouse model. The inflammatory response peaked at the fourth exposure to hair dye after which there was an up-regulation of regulatory T cells and IL-10 producing cells. In addition to being potent skin sensitizers that activate inflammatory T cells, hair dyes also induce anti-inflammatory mechanisms. This might explain why many consumers can use hair dyes repeatedly without developing overt allergies, but also raises the question whether the immune modulatory effects of hair dyes might influence the development of autoimmune diseases and cancers. Br J Dermatol 2010; 163: 992-98.

        Long-term follow-up study of occupational hand eczema

        Mälkönen et al. report the prognostic risk factors for the continuation of occupational hand eczema (OHE) in 605 patients after a follow-up of 7-14 years. The hand eczema had healed (no eczema during the last year) in 40% of OHE patients. In the logistic model, risk factors for the continuation of OHE were the long duration of hand eczema before diagnosis, respiratory atopy, skin atopy, and continuation in the same occupation. Since the majority of signs for poor long-term prognosis are detectable in the early stages, the importance of early diagnosis and intervention is emphasised. Br J Dermatol 2010; 163: 999-1006.

        Hair removal in hirsute women with normal testosterone levels: a randomized controlled trial of long-pulsed diode laser vs. intense pulsed light

        Haak et al. compared the efficacy and safety of intense pulsed light (IPL) vs. long-pulsed diode laser (LPDL) in a group of hirsute women with intrinsically normal or medically normalized testosterone levels. Thirty-one women received six allocated split-face treatments with IPL and LPDL. Patients responded equally well and obtained significant hair removal efficacies from IPL and LPDL treatments with 77% to 40% hair reduction for IPL and 68% to 34% for LPDL during the 1–6-month follow-up period. At 6 months follow-up, there was no significant difference between treatments in terms of hair reduction (P = 0.427), patient assessment of hairiness (P = 0.250) and patient satisfaction (P = 0.125). Pain scores were consistently higher for IPL than LPDL. Br J Dermatol 2010; 163: 1007-13.

        The role of sunlight exposure in determining the vitamin D status of the U.K. white adult population

        Webb et al. performed a single-centre, prospective cohort study to examine whether personal sunlight exposure levels can provide vitamin D sufficient (≥ 20 ng mL−1) status in the U.K. A late summer peak of around 32 ng mL−1 is required in order to remain vitamin D sufficient year round. Currently the majority of the U.K. population fails to reach this post-summer level and becomes vitamin D insufficient during the winter. It is proposed that optimal vitamin D status might be better considered as an end of summer rather than a year-round goal. Br J Dermatol 2010; 163: 1050-55.

        Activating BRAF Mutations in Eruptive Melanocytic Nevi

        Sekulic et al. evaluated whether activating BRAF mutations may play a role in the genesis of eruptive melanocytic nevi (EMN). Genomic DNA was isolated from 20 EMN from a 6-mercaptopurine (6-MP) treated patient. The BRAF V600E mutation was identified in 85% of examined EMN. Results implicate mutational activation of BRAF-MAPK pathway as a factor in development of EMN in the setting of 6-MP treatment. The mechanism leading to development of EMN in this, and potentially other patients, may relate to synergistic mutagenic effects of thioguanines and UVA. Together with the documented importance of BRAF mutations in melanoma development and maintenance, these findings highlight the importance of UVA protection, especially in the setting of thiopurine treatment. Br J Dermatol 2010; 163: 1095-98.