[Dissecting cellulitis of the scalp: a retrospective study of 7 cases confirming the efficacy of oral isotretinoin]. / Cellulite disséquante du cuir chevelu: étude rétrospective de 7 cas confirmant l'efficacité de l'isotrétinoïne per os.

BACKGROUND: Dissecting cellulitis of the scalp (DCS) is a rare and long-standing disease and its aetiopathogenesis remains unclear. Various therapeutic alternatives exist. We attempted to assess the efficacy of oral isotretinoin in a series of patients. PATIENTS AND METHODS: Seven cases of DCS followed and treated by one of the authors at the Sabouraud Centre in the Saint-Louis Hospital between 2007 and 2013 were retrospectively studied and the efficacy of oral isotretinoin was evaluated. RESULTS: The seven patients included were males aged between 22 and 39 years, with alopecic nodules on the occiput (two cases) or the top of the vertex (five cases). Most patients were given oral isotretinoin at a dosage of 0.75mg/kg/day for at least nine months. The outcome was satisfactory with complete healing of the lesions and good regrowth in all cases. Follow-up after recovery lasted between 16 and 42 months. CONCLUSION: Based on published studies and the results of the present study, oral isotretinoin at a dose of 0.75mg/kg/day may be proposed as first-line treatment for DCS.

Time- and dose-dependent effects of roundup on human embryonic and placental cells.

Roundup is the major herbicide used worldwide, in particular on genetically modified plants that have been designed to tolerate it. We have tested the toxicity and endocrine disruption potential of Roundup (Bioforce on human embryonic 293 and placental-derived JEG3 cells, but also on normal human placenta and equine testis. The cell lines have proven to be suitable to estimate hormonal activity and toxicity of pollutants. The median lethal dose (LD(50)) of Roundup with embryonic cells is 0.3% within 1 h in serum-free medium, and it decreases to reach 0.06% (containing among other compounds 1.27 mM glyphosate) after 72 h in the presence of serum. In these conditions, the embryonic cells appear to be 2-4 times more sensitive than the placental ones. In all instances, Roundup (generally used in agriculture at 1-2%, i.e., with 21-42 mM glyphosate) is more efficient than its active ingredient, glyphosate, suggesting a synergistic effect provoked by the adjuvants present in Roundup. We demonstrated that serum-free cultures, even on a short-term basis (1 h), reveal the xenobiotic impacts that are visible 1-2 days later in serum. We also document at lower non-overtly toxic doses, from 0.01% (with 210 microM glyphosate) in 24 h, that Roundup is an aromatase disruptor. The direct inhibition is temperature-dependent and is confirmed in different tissues and species (cell lines from placenta or embryonic kidney, equine testicular, or human fresh placental extracts). Furthermore, glyphosate acts directly as a partial inactivator on microsomal aromatase, independently of its acidity, and in a dose-dependent manner. The cytotoxic, and potentially endocrine-disrupting effects of Roundup are thus amplified with time. Taken together, these data suggest that Roundup exposure may affect human reproduction and fetal development in case of contamination. Chemical mixtures in formulations appear to be underestimated regarding their toxic or hormonal impact.