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Notes: Summary Dermal dendrocytes (DDs) are dendritic cells that exhibit immunoreactivity for factor XIIIa, and are frequently found in conjunction with basal cell carcinomas (BCCs). Imiquimod was applied to 12 superficial BCCs every 3 days for 8 weeks. One week after completion of treatment, seven lesions appeared to have resolved, while five displayed evidence of residual BCC. Prior to initiation of treatment, the seven imiquimod-responsive BCCs were surrounded by numerous DDs, whereas the five imiquimod-resistant BCCs had fewer DDs next to them at the time of entry into the study. It appears that the pretreatment density in DDs may affect the efficacy of imiquimod in eradicating skin tumours.

Notes: Nail surfaces of toe-nail fragments were analysed by optical profilometry in patients treated with two different dosages of itraconazole: 200 mg continuous dosing for 12 weeks, or a pulse-dose regimen of 1 week per month of 400 mg itraconazole daily for 3–4 months. The use of the latter regimen seemed clinically to increase nail growth, which was accompanied in several patients by the occurrence of nail surface irregularities. This aspect was studied by computerized optical profilometry. Nail beading was characterized by a higher number of peaks and a larger mean roughness value (Ra). Such findings are reminiscent of other nail alterations resulting from a faster matrix turnover. A substantially greater number of peaks and larger Ra were found in the patients receiving the pulse treatment than in those receiving the continuous dose regimen. Pulse therapy with itraconazole therefore appears to modify the structure of the nail plate, probably as a result of, or in association with, an increased rate of growth.

Notes: Des dystrophies du cheveu sont acquises ou ont un déterminisme génétique. Elles peuvent être isolées ou associées à un trouble du cycle de croissance. Quelles que soient les anomalies, elles peuvent toutes être aisément reconnues sur un trichogramme et leur microanatomie précisée par l'observation en microscopie électronique à balayage.Une interprétation pathogénique peut être proposée pour certaines dystrophies se marquant par une modification du calibre du cheveu. En effet, un dysmorphisme pilaire aura pour cause une altération frappant soit les cellules kératinisées, soit les cellules métaboliquement actives. Dans le premier cas, un traumatisme physique ou chimique altère la structure des cellules kératinisées du cheveu après son émergence de la peau.Dans le deuxième cas, la perturbation génétique ou acquise se marque au niveau des cellules matricielles ou en voie de différenciation. Elle est le reflet d'une perte de contrôle de l'homéostasie de croissance du cheveu sous la dépendance de la forme et du volume de la matrice (donc de la papille), de la proportion de cellules inscrites dans le cycle de division cellulaire, de la durée du cycle, de l'augmentation de volume de chaque cellule pendant sa différenciation et de sa vitesse de migration. Evaluation of the dynamics of hair dystrophy by optical and scanning electron microscopy 〈section xml:id="abs1-2"〉〈title type="main"〉SummaryThe size and shape of a segment of a hair are two fairly constant parameters. Their homeostasis reflects a precise regulation of the size and shape of the matrix (therefore of the papilla), of the proportion of cells normally engaged in the cycle of cellular division, of the duration of this cycle, of the increase in the average volume of cells during differentiation, and of their speed of migration. Any disturbance in this precise pattern causes dystrophies that are acquired or genetically determined. These abnormalities in hair structure can be observed and recognised by optical and by scanning electron microscopy.The metabolic pathology acting through the matrix cells has to be differentiated from other alterations induced on the hair shaft by physical or chemical agents. These latter alterations can be present all along the hair shaft after its emergence from the skin or rise in tiers. These injuries are cumulative, irreversible and increase fragility and brittleness of the hair shaft.

Notes: Dandruff is known to be controlled by fungistatic shampoos active against Malassezia spp. These products also remove the loosely attached scales. This study was performed to assess the effect of a 5-min residence time on the efficacy of antidandruff shampoos. Two commercially available shampoos were used in two groups of 21 panelists with severe dandruff. They contained either 1% ketoconazole or 1% piroctone olamine. In each group, intraindividual comparisons were made by a split-scalp design between the effect of a 5-min residence time versus no residence time. Both shampoos induced significant reductions in scaliness and yeast colonization. The beneficial effects were obvious immediately after one single shampooing and 3 days later as well. The improvement was greater with a 5-min residence time. The piroctone olamine treatment benefited more than the ketoconazole treatment from the extension of shampoo-exposure time. In conclusion, the benefit of a residence time in treating dandruff is documented. The level of improvement in efficacy may vary according to the nature of the shampoo.

Notes: Cutaneous irritation is a stereotyped response of the skin to any physical or chemical insult. Its main manifestations encompass inflammatory erythema and an alteration of the cutaneous microrelief showing increased roughness, dehydration and erratic desquamation. Several instrumental methods can indirectly assess the issues of cutaneous irritation on human stratum corneum.The aim of the present study was to measure the speed of propagation of ultrasound shear waves in the skin irritated by anionic surfactants. The study was performed in 25 healthy subjects of both sexes. Occlusive patches of a 10% solution of anionic surfactants were applied to a forearm of each volunteer. The other forearm served as an untreated control site. Patches remained in place for 24 h. Three hours later, another patch was placed again for 21 h. Resonance running time measurements (RRTM) of the ultrasound shear wave were performed using a Reviscometer® RVM 600. Measurements were performed at entry in the study and 2 days after removing the second patch.Desquamative xerosis was obvious at the sites patched with the surfactant solution. RRTM values were significantly (P 〈 0.0001) lower than those at the control site. Hence, the speed of propagation of ultrasound shear waves was shown to be increased at an irritated site compared to an intact site.In conclusion, this study shows that the propagation speed of ultrasounds is influenced by the skin surface nature, being considerably increased in skin altered by surfactants.

Notes: Chronobiology governing the hair cycle is a fascinating and complex process. Both the hair growth cycle and the hair shaft growth are coordinated and depend on the interplay of different biological signals and various exogenous stimuli. A latency period may occur between hair shedding (teloptosis, exogen phase) and the early emergence of the next anagen VI stage. This lag time referred to on the hair eclipse phenomenon likely depends on the influence of a series of distinct synchronizers, and does not represent per se a peculiar hair cycle phase. It is the result of some dysregulations of the hair cycling, involving early teloptosis, delayed anagen I initiation or stunted hair growth at any stage between the anagen I and anagen V phases. As such, the hair eclipse phenomenon may be an erratic process occurring in physiopathological conditions affecting hair follicles singly or in focal to generalized patterns. It may be more frequent when it follows synchronized teloptosis occurring in telogen effluvium (newborn alopecia, post-partum alopecia, seasonal alopecia and alopecia areata). It may also be prominent when microinflammation is abutted on the permanent portion of the hair follicle as in dandruff, seborrhoeic dermatitis, androgenic alopecia and photoageing baldness. Local synchronizers such as growth factors and other mediators may eventually be lacking or involved in the hair eclipse phenomenon. Their identification and characterization might drive new corrective or preventive applications.

Notes: Hair shedding and hair thinning have been reported to be affected by dandruff and seborrhoeic dermatitis. The present study was conducted in 150 men presenting with telogen effluvium related to androgenic alopecia associated with dandruff. They were randomly allocated to three groups receiving each one of the three shampoos in the market containing either 1% ketoconazole (KTZ), 1% piroctone olamine (PTO) or 1% zinc pyrithione (ZPT). Shampoos had to be used 2–3 times a week for 6 months. Hair shedding during shampoo was evaluated semiquantitatively. Hair density on the vertex was evaluated on photographs using a Dermaphot. Trichograms were used for determining the anagen hair percentage and the mean proximal hair shaft diameter using computerized image analysis. The sebum excretion rate (SER, μg cm−2 h−1) was also measured using a Sebumeter®.The three treatments cleared pruritus and dandruff rapidly. At end point, hair density was unchanged, although hair shedding was decreased (KTZ: −17.3%, PTO: −16.5%, ZPT: −10.1%) and the anagen hair percentage was increased (KTZ: 4.9%, PTO: 7.9%, ZPT: 6.8%). The effect on the mean hair shaft diameter was contrasted between the three groups of volunteers (KTZ: 5.4%, PTO: 7.7%, ZPT: −2.2%). In conclusion, telogen effluvium was controlled by KTZ, PTO and ZPT shampoos at 1% concentration. In addition, KTZ and PTO increased the mean hair shaft thickness while discretely decreasing the sebum output at the skin surface.

Notes: Synopsis The dry skin appearance of the legs is a common complaint in winter. We studied such a condition using a multi-pronged approach combining video recording under ultraviolet light, cyanoacrylate skin surface stripping and squamometry X. Two main distinct patterns of alteration of the skin surface were identified. Flexural xerosis corresponded to cracking in parallel primary lines of the stratum corneum. Accretive xerosis referred to hyperkeratosis of the plateaux delineated by the criss-cross pattern of the skin surface creases. Two distinct commercially available formulations aiming to treat dry skin yielded almost similar efficacy. For both products, flexural xerosis responded more rapidly than accretive xerosis. Résumé L’aspect de peau sèche des jambes est une situation fréquente en hiver. Nous l’avons étudiée par une approche diversifiée combinant l’examen par video en lumière ultraviolette, la biopsie de surface au cyanoacrylate et la squamométrie X. Deux types principaux et distincts d’altérations de la couche cornée ont été identifiés. La xérose flexurale correspond à la fracture de la couche cornée dans des lignes primaires orientées parallèlement les unes aux autres. La xérose par accumulation désigne l’hyperkératose des plateaux délimités par le réseau des lignes primaires. Deux formulations pour peaux sèches disponibles sur le marché ont apporté des résultats bénéfiques comparables. Pour les deux produits, la xérose flexurale a répondu plus rapidement que la xérose d’accumulation.

Notes: Dandruff adherence to hair shafts is a visible annoying phenomenon. The aspect can be recorded by different means including the ultraviolet light-enhanced visualization (ULEV) method and microscopy. We present another quantitative method. Hairs were clipped from the parietal scalp area of 25 volunteers complaining of dandruff. They were firmly applied onto cyanoacrylate-coated microscopic slides. Hairs were lifted up after 15–20 s leaving a cast in the adhesive coat. Dandruff were thus harvested from the hair shafts and remained attached to the cyanoacrylate coat. After staining, the material was submitted to image analysis to derive the dandruff density per unit length of hairs. In 11/25 subjects, a correlation was found between the width of the hair casts and the dandruff density. This method does not collect all dandruff along hair shafts, but data are likely representative of the whole corneocyte load.