Claudine Franchimont

Beyond a Glimpse at Seasonal Dry Skin: A Review

On clinical grounds, the so-called dry skin corresponds in reality to a rough, sometimes flaky and scaly stratum corneum. The spectrum of xerotic disorders is quite large encompassing diverse aetiologies and physiopathological pathways. The clinical assessment of these conditions relies on close visual and tactile inspection. EEMCO guidances were proposed in this field for subject and expert evaluations. Scoring systems include analogue scales, the overall dry skin score and the SRRC score combining the grading of scaliness, roughness, redness and cracks. The dry skin extent area and severity index is defined for the dermatological evaluation of the entire body surface. The use of a video camera equipped with an internal ultraviolet light illumination unit is very informative and allows better comparative assessments.

Repair kinetics of stratum corneum under repeated insults.

Background: The stratum corneum (SC) structure and functions are altered by surfactants. Enhancing the repair mechanisms is a goal for some skin care formulations. Aim: To design an experimental procedure allowing the discrimination of repair efficacy for topical products applied to threatened SC. Method: Controlled SC strippings followed by repeated forearm soak sessions in surfactant solutions were used to compromise the SC barrier function in 20 volunteers. Two test formulations were compared. They were applied twice daily for 2 weeks before initiating the SC damages, and for the next 2 weeks while sustaining the procedure of soak sessions. Daily assessments involved objective measurements of parameters including transepidermal water loss, the value of the passive sustainable SC hydration and the epidermal turnover rate using the dihydroxyacetone test. Result: The experimental procedure allowed to clearly distinguish the differences in the kinetics of SC repair between the topical formulations. In the present study design, the repair of the barrier function mirrored the SC renewal. Conclusion: The present experimental design slows down the repair rate of the SC barrier function. Thus, it increases the sensitivity of biometrological measurements assessing some of the major SC properties. It also better mimics the common in vivo situation experienced by subjects chronically exposed to irritant xenobiotics.

Androgenic alopecia and stress-induced premature senescence by cumulative ultraviolet light exposure.

Background: Ultraviolet light radiations (UVR) may be responsible for hair cycle synchronization and telogen effluvium in the animal and humans. The effect if any of cumulative UVR on chronic hair shedding and androgenic alopecia (AGA) is largely unknown. Objective: To compare the severity of AGA with the extent of solar elastosis. Method: The present study combining immunohistochemistry and computerized image analysis was undertaken in 140 men with AGA and 50 non-alopecic men. Solar elastosis was identified using the antibody to lysozyme, and collagen was revealed by Sirius red staining. The number and diameter of hair shafts were also assessed. Results: The scalp dermis was significantly thicker in AGA than in unaffected subjects. The difference was mainly due to a severer elastosis in baldness. The earliest signs of solar elastosis preceded hair thinning. When elastosis was thicker than 0.2 mm, a negative exponential correlation was found between hair diameter and severity of solar elastosis. Conclusion: Chronic UVR exposure of the scalp may affect the hair cycle and be one of the exogenous factors influencing negatively the progression of AGA. The induction of stress-induced premature senescence by reactive oxygen species and micro-inflammation might be operative at the level of the follicular stem cells.

Photosclerosis induced by long wave length ultraviolet light and psoralens

In highly photosensitive patients, PUVA therapy can injure the superficial microvasculature, which results in oedema, fibrosis of the dermis and coating of capillary venules by an amorphous material.

Proliferation Rate of Cutaneous T Cell Lymphomas in the Skin — Relationship with Histologic Pattern and Cytology

Growth of malignant lymphomas depends in part on the proliferation of atypical lymphoid cells. We evaluated after incorporation of tritiated thymidine the rate of proliferation of lymphoid cells homing to the skin in cutaneous T cell lymphomas (CTCL). The proportion of lymphoma cells in the dermal infiltrate was determined by optical and transmission electron microscopy.

Intense Pulsed Light in Infantile Hemangiomas

For more than 70 years, the watchful-waiting management of infantile strawberry hemangiomas still prevails in a number of clinical settings. This concept appears now outdated since the introduction of well-suited beta-blockers, as well as noncoherent light and laser therapies. The aim of this work was to revisit the effect of intense pulsed light (IPL) therapy on infantile hemangioma. Information was collected from the peer-reviewed literature and illustrated by personal cases. When applied early in the evolution of infantile hemangiomas, IPL treatment stops the growth phase and induces regression with minimal cosmetic adverse effects and psychological damage. Initiating an adequate treatment is important because damage due to hemangiomas can be diminished by a timely and adequate approach. Beta-blockers have revolutionized the therapeutic strategy of infantile hemangiomas. The flash light therapy (IPL) represents an alternative therapy for some patients.

Cyanoacrylate Skin Surface/Follicular Stripping

Cyanoacrylate skin surface stripping (CSSS), also called skin surface biopsy and follicular biopsy, is a convenient minimally invasive method allowing collection of a uniform sheet of stratum corneum and horny follicular casts. The method has a number of applications in cosmetology, diagnostic dermatology and experimental designs. A series of derived analytic procedures include xerosis grading, corneofungimetry, dynamics of stratum corneum renewal and comedometry.

Corneosurfametry and Corneoxenometry

Corneosurfametry and corneoxenometry are two related investigative methods allowing safe assessment of some irritation potential of surfactants and other xenobiotics, respectively. The method entails harvesting a sheet of the stratum corneum using the cyanoacrylate skin surface procedure. The neat or diluted test product is applied ex vivo for a given period of time at defined temperatures. The material is then rinsed and stained, and the color is measured using reflectance colorimetry in the L*a*b* system. The more the color is intense, the more the product is at risk of in vivo irritation.