Background: During photoaging, the density of melanin chromatophores is heterogeneous in the epidermis. Aims: To define the patterns of pheomelanin-enriched melanotic hypermelanosis of the face in phototype II subjects and to assess the effect of depigmenting agents. Azelaic acid and glycolic acid were tested as well as a soy extract, reported to reduce pigmentation through interaction with the protease-activated receptor 2 (PAR-2) of keratinocytes. Method: Evaluations were made by image analysis of high magnification pictures obtained by a video camera equipped with an internal ultraviolet-emitting unit (Visioscan^®). Results: Three patterns of subclinical facial hypermelanosis were recognized including the spotty perifollicular type, the accretive globular type and the elongated type of the sunny side of wrinkles. Azelaic acid and the soy extract led to significant skin lightening after a 3-week treatment. By contrast, glycolic acid showed an inconsistent effect. Conclusion: Sensitive fluorescence video recording combined with image analysis represents an advance in the noninvasive assessment of the mottled subclinical skin pigmentation. The depigmenting effect observed with the soy extract indicates that the inhibition of PAR-2 may be a novel way to approach certain pigmentary disorders of the skin.

Background:  Basement membrane alterations are common in malignancies, and they may indicate tumoral aggressiveness. Distinct patterns of tumoral coverage by collagen IV were reported in nodular and aggressive basal‐cell carcinomas (BCCs). Differential expressions of α (IV) collagen chains were also shown on frozen sections. The aim of our work was to document the immunohistochemical expression of α1, α3, and α5 (IV) collagen chains in BCC after routine fixation and processing. Methods:  The patterns of distribution of α1 (IV), α3 (IV), and α5 (IV) collagen chains were studied in 20 formalin‐fixed and paraffin‐embedded BCCs showing different infiltrative patterns. One trichoblastoma was used as control. Results:  In nodular BCCs, the expression of α5 (IV) collagen chain was downregulated and uneven. By contrast, α1 (IV) collagen chain expression was preserved around these tumors similar to the surrounding skin. However, the α1 (IV) collagen chain expression was discontinuous or absent in BCC areas showing an infiltrative pattern of extension. The α3 chain was absent both underneath all BCCs and non‐neoplastic skin. Conclusions:  The basement membrane alterations around nodular BCCs involved more precisely the α5 (IV) collagen chains. Defects in α1 (IV) collagen chain expression seemed to be associated with a tumoral invasive and infiltrative pattern. The biological significance of these findings is unclear.

Background: Some antibiotics represent a mainstay in acne treatment. However, studies comparing their efficacies are rare. Aim: To evaluate the clinical and in vivo antibacterial effect of lymecycline and minocycline at different dosages. Method: Eighty-six patients with moderate to severe acne were enrolled in a randomized, double-blind, intent-to-treat study comparing in three parallel groups the effect of (1) lymecycline 300 mg daily for 12 weeks, (2) minocycline 50 mg daily for 12 weeks and (3) minocycline 100 mg daily for 4 weeks followed by 50 mg daily for 8 weeks. Evaluations were made at the screening visit and at five on-treatment visits. They consisted of clinical counts of acne lesions and evaluations of bacterial viability using dual flow cytometry performed on microorganisms collected from sebaceous infundibula by cyanoacrylate strippings. Results: Patients receiving minocycline 100/50 mg had the best clinical outcome, particularly in the reduction of the number of papules. By the end of the trial, the microbial response to minocycline 100/ 50 mg was also superior to either of the other two treatments. There were less live and more dead bacteria. Conclusion: In this trial, minocycline 100/50 mg was superior for the treatment of inflammatory acne when compared to lymecycline 300 mg and minocycline 50 mg.