Jean-François Hermanns

Unraveling the Patterns of Subclinical Pheomelanin-Enriched Facial Hyperpigmentation: Effect of Depigmenting Agents

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.

From axioms to new insights into dandruff.

This review addresses the current concepts about dandruff. The nature, origin and treatments of such skin conditions are scrutinized. The role of Malassezia spp. and other triggering factors is highlighted.

Assessment of Topical Hypopigmenting Agents on Solar Lentigines of Asian Women

Background: So-called darkened age spots encompass distinct pathological processes. The efficacy of topical depigmenting agents is difficult to objectivate. Objective: To assess the hypopigmenting effect of three cosmetic formulations using objective biometrological methods. Methods: 50 women of South-East Asian ancestry were enrolled in this pilot study. They had solar lentigines according to dermoscopic criteria. The lesions were treated by topical hypopigmenting formulations. Products were applied twice daily for 2 or 3 months. Assessments at 1-month intervals were made using narrow-band reflectance spectrophotometry, image analysis of video-recorded ultraviolet light reflection and photodensitometry- and image-analysis-assisted corneomelametry. Results: A 20% azelaic acid formulation and another one containing 5% ascorbyl glucosamine, 1% kojic acid and α-hydroxyacid esters appeared inefficacious on solar lentigines. A stabilized soy extract showed a better although modest lightening effect when assessed by corneomelametry. The subclinical or faint mottled skin revealed by ultraviolet light examination better responded (p < 0.05) to treatments. Conclusion: Focal epidermal hyperpigmentation is better controlled by topical whitening agents when the increase in melanin content reflects a modest functional hyperactivity of melanocytes.

High-resolution epiluminescence colorimetry of striae distensae.

Background  Colours of striae distensae are often different from that of the surrounding skin. A close look using dermoscopy discloses distinct patterns of melanized networks at these sites. The aim of the study was to design a method of high‐∖resolution analytical analysis of the skin colours using the combination of photographic dermoscopy and small field reflectance colorimetry.

Beneficial Effects of Softened Fabrics on Atopic Skin

There is general concern about the possible cutaneous adverse effects of wearing garments treated with household laundry products, particularly on atopic skin. Our objective was to compare softened and non- softened fabrics in a forearm wet and dry test, under conditions simulating real-life conditions. Twenty atopic volunteers entered a single-blind 12-day (3 sessions per day) forearm wetting and drying test. Cotton fabrics were machine washed and liquid fabric conditioner was added or not to the final rinse. To simulate conditions of skin damage, a dilute solution of sodium lauryl sulphate was applied under occlusion to the forearm of each volunteer before the start of the study. Skin effects were evaluated by visual grading (redness, dryness and smoothness), squamometry and in vivo instrumental measurements (capacitance, transepidermal water loss and colorimetry). Rubbing of atopic skin with fabrics generally resulted in discrete to moderate alterations of the structure of the stratum corneum. Both for control and pre-irritated skin, all measured parameters indicated that softened fabric was less aggressive to the skin than unsoftened fabric. In the case of pre-irritated skin, the recovery of the skin was significantly faster when rubbed with softened than with unsoftened fabrics. In conclusion, softened fabrics help mitigate the skin condition in atopic patients.

Morphometric Study of Cauliflower Collagen Fibrils in Dermatosparaxis of the Calves

The abnormal cauliflower collagen fibrils present in the skin of dermatosparactic calves were studied by electron microscopy and computerized image analysis. The structure of the fibrils is heterogeneous and varies according to their location in the dermis. Cauliflower fibrils seems due to a defect in the lateral cohesion between the constitutive procollagen polymers. This is associated with the presence of a non-collageneous material larger than the aminopropeptide surrounding the procollagen polymers, while the volume occupied by procollagen in each fibril is comparable to that of collagen in normal fibrils.

Stéréologie de l’interface dermo-épidermique

The architecture and the plasticity of the dermo-epidermal interface of normal and pathological human skin have been studied by scanning electron microscopy. Biopsies were incubated in a sodium bromid

Hedgehog ringworm in humans and a dog.

Abstract We report 3 related cases of human dermatophytosis and 1 dog dermatophytosis likely caused by contact with a European hedgehog. Trichophyton erinacei was isolated from stratum corneum samples. This type of zoophilic dermatophytosis is rare in south-east Belgium and probably in the rest of the country as well

Laddering melanotic pattern of Langer’s lines in skin of colour

Mechanobiological stimulation of the skin influences melanocyte activity. The clinical impact on melanocytes can be perceived by dermoscopy. Our aim was to assess the orientation of Langers lines using the combination of ultrasound shear wave propagation and dermoscopy in 70 adults of darker skin complexion. On the back, 44/70 patients showed a honeycomb melanotic pattern without any main orientation. By contrast, a streaky parallel pattern of melanotic lines oriented in the direction of Langers lines was found in 26/70 patients. Indeed, the maximum speed of ultrasound propagation was found parallel to the main orientation of the laddering melanotic pattern. The parallel melanotic pattern probably reflects the main orientation of the epidermal rete ridges aligned in the direction of Langers lines. This aspect could be ascribed to the deepening of these structures and/or to mechanobiology affecting melanocytes. The aspect is reminiscent of that previously described in striae distensae and atrophic scars.

Cyclic Catamenial Dermatoses

Circulating sex hormones follow major fluctuations during the ovarian cycle. The so-called premenstrual syndrome represents a global condition grouping the diversity of catamenial disorders. At the skin level, the sebaceous gland activity is obviously modulated by these endocrine fluctuations. In addition, a series of pathological manifestations take place simultaneously in some women. Among them, the most frequent skin condition is represented by catamenial acne. Concurrently, the autoimmune progesterone dermatitis refers to a diversity of skin alterations resulting from an immune reaction to progesterone. It is present under variable clinical aspects. A series of other recurrent skin conditions are not specifically induced but are merely exacerbated at the end of the ovarian cycle.