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Sophie Mac-Mary,1 Itziar Zornoza Solinis,2 Océane Predine,1 Jean-Marie Sainthillier,1 Christelle Sladen,2 Mike Bell,2 Mark O’Mahony2 1Skinexigence, Besançon, France; 2Walgreens Boots Alliance, Nottingham, UKCorrespondence: Sophie Mac-MarySkinexigence SAS, 2 Rue Paul Milleret, 25000, Besançon, FranceTel +33 3 81 88 95 51Email smac@skinexigence.comBackground: The aetiology of infraorbital dark circles is complex and multi-factorial. The aim of this research was to measure and characterize dark circles and to determine the physiological changes associated with the occurrence of this aesthetically unpleasing issue.Materials and methods: Clinical, photographic and instrumental assessments were performed on Caucasian skin to determine the most appropriate methodologies to measure dark circles, comparing different zones of the infraorbital region in subjects with and without dark circles. Exploratory studies were also carried out on African and Far East Asian skin, as well as on tracking the natural variation of dark circles over seven days in Caucasian subjects.Results: Under-eye dark circles in Caucasian subjects are characterized by significantly darker coloured skin and higher colour deviations between the dark circle region and surrounding areas of skin. Multispectral image analysis produced a higher melanin index in subjects with dark circles, suggesting hyperpigmentation in the affected area, in addition to a higher haemoglobin index. The higher haemoglobin index, combined with preliminary assessments of the vascular network by videocapillaroscopy, suggests there may be more dilated, thicker or increased numbers of capillaries in subjects with dark circles. Ultrasound analysis showed a significant difference in skin thickness between the two groups of subjects linking the appearance of dark circles to thinner skin under the eye. Many of these trends were also observed in African and Far East Asian skin. The results also showed intra-individual, intra-day and inter-day variability of dark circle intensity in subjects with Caucasian skin.Conclusion: Three key physiological factors associated with the occurrence of infraorbital dark circles are hyperpigmentation, a tendency for more dilated, thicker or increased number of capillaries and thinner skin in the under-eye area. The combination of these three factors provides a robust indication of the presence of infraorbital dark circles.Keywords: dark circles, infraorbital, ultrasound imaging, image processing, multispectral imaging, pigmentation

Les cosmetiques sont appliques sur la peau saine, et revendiquent des actions de nettoyage, parfumage ou protection (definition du code de la sante publique). Sous l’impulsion de dermatologues, scientifiques et industriels, la recherche en cosmetologie s’est developpee et permet desormais d’objectiver leur efficacite de maniere scientifique et a l’aide de methodes toujours plus pointues, en laboratoire ou directement sur l’homme au cours d’essais cliniques. Cet article traite des principales techniques et des contraintes a prendre en compte dans le cadre de la science de la mesure de la peau : la « biometrologie cutanee ».

The purpose of the study was to evaluate the effects of corticosteroids on histamine release and to compare their potency with the MacKenzie classification based on their vasoconstrictor effects. Thanks to ex vivo cutaneous microdialysis, we studied histamine-induced release over a period of time on excised abdominal skin from women. Eight corticosteroids were topically applied with occlusive dressing onto the skin, above probes, before anti-IgE injection. Histamine levels were assessed by an EIA method. In order to compare the different corticosteroids, AUC was calculated allowing an estimation of the amount of released histamine for 60 min of ex vivo cutaneous microdialysis. Diflucortolone 0.1% and micronized betamethasone dipropionate 0.05% are considered as corticosteroids with high potency in MacKenzie classification. Betamethasone dipropionate associated with propylene glycol 0.05%, belongs to a stronger class in Mackenzie classification. Our results showed that the decrease in histamine release was more important with difluocortolone than with both of these corticosteroids. Therefore there was no correlation between the vasoconstrictor potency of topical corticosteroids and their ability to inhibit histamine release.

International audience; Skin ageing is a complex process determined by the genetic endowment of individual and environmental factors, such as sun exposure. The effects of skin ageing are mostly encountered in the superficial dermis and in the epidermis. We have previously demonstrated in vivo the beneficial effect of a topically applied formula of 5% vitamin C in the treatment of skin ageing. Another active compound, madecassoside extracted from Centella asiatica, known to induce collagen expression and/or to modulate inflammatory mediators, might thus prevent and correct some signs of ageing. A randomized double-blind study was carried out on photoaged skin of 20 female volunteers to investigate the effects of topically applied 5% vitamin C and 0.1% madecassoside on the clinical, biophysical and structural skin properties. After 6 months of treatment, we observed a significant improvement of the clinical score for deep and superficial wrinkles, suppleness, firmness, roughness and skin hydration. These results were corroborated by measurements of skin elasticity and semi-quantitative histological assessment of the elastic fibre network in the papillary dermis. Two-thirds of the subjects showed an improvement. The re-appearance of a normally structured elastic fibre network was observed. Our results revealed a functional and structural remodelling of chronically sun-damaged skin.

The development of in vivo microdialysis has made it possible to monitor cutaneous free flaps in maxillo-facial surgery. A microprobe inserted in the free flap dermis collects a microdialysate enabling measurement of dermal metabolites such as glucose, lactate, pyruvate, or glycerol. The monitoring curves are predictive of ischemia-related tissue injury. Hourly measurements provide a reliable method for early diagnosis of venous or arterial thrombosis. Revision surgery can then be undertaken if needed to repair microanastomoses before clinical alteration. This technique has been compared with validated flaps monitoring systems such as temperature probe, transcutaneous oxygen tension monitoring, and laser Doppler flowmetry. Microdialysis has several advantages: objective measurements, different curves for venous and arterial thrombosis, early diagnosis. Accessibility to oral cavity or pharyngeal flaps requires careful clinical analysis (microprobe fixation, anatomy and choice of flap).

Summary Background Different noninvasive bioengineering techniques exist to study the microvasculature of the skin and the dynamics of the microcirculation. The goal of these techniques is to visualize the skin capillary circulation easily and directly. Indeed, this information is irreplaceable to study the physiology and physiopathology of the skin capillary circulation efficiently. Aims Capillaroscopy and video-capillaroscopy techniques are presented with different methods to study the capillary structure of the skin. Methods he methods presented in this work include image processing analysis combining morphology, statistics, geometry, and neural network detection designed to quantify the microcirculation and to follow its evolution. To illustrate the combination of these techniques and methods, different examples of their application are described, in dermatology (hypertension, venous insufficiency, age-related changes) as well as in cosmetology (rosacea and erythrosis assessment). Conclusion The determination of structural or dynamic changes in the cutaneous microcirculation belongs to the noninvasive techniques of the biometrological domain. Thus, every capillary modification resulting from topical cosmetic products, or chemical agents can be observed. In pathology, numerous conditions can be better examined with this system. Associated with the potential of numerical image analysis, capillaroscopy techniques will probably extend their application fields to the assessment of the influence of arterial and venous diseases on the skin nutritional circulation.

Background: Atopic dermatitis (AD) is a chronic inflammatory skin disease in which reactive oxygen species (ROS) may be involved. Iron catalyses ROS formation and ascorbic acid (AA) scavenges these species. Objective: The aim of this work was to determine iron and AA levels in AD patients’ dermis and to compare their concentrations with those of healthy volunteers’ dermis. Methods: Five AD patients and 5 healthy subjects (controls) were enrolled in this study. Iron and AA were collected from human dermis by microdialysis and assessed by atomic absorption spectrometry and gas chromatography-mass spectrometry, respectively. Results: The AD dermis demonstrated higher iron concentrations (44.3 ± 4.6 µg/l) compared to controls (21.8 ± 1.2 µg/l) as well as a significantly lower concentration of AA (46.7 ± 0.6 vs. 176.8 ± 14.5 µg/ml, respectively). Conclusion: These results suggest that iron and AA dermis levels could be indicators of inflammatory tissues and might be implicated in dermatological diseases such as AD.

Objective: To evaluate, in the context of a randomized study, the ‘Sole Si Sole No GISED’ project, the effectiveness of an educational intervention to improve sun protection behaviour in schoolchildren. Methods: A large number of primary schools (classes II and III) in Italy were randomized to an educational intervention or control group: The intervention was conducted by trained teachers using ad hoc developed materials. Attitudes toward sun exposure and behaviour while in the sun were assessed at baseline and 1 year after concluding the educational intervention. In a subgroup of children, melanocytic naevi were counted on the upper limbs at the same intervals. The pilot phase of the study was started in 2001. Results: During the pilot phase, a total of 4,233 children was recruited. Of these, 2,116 were randomized to the active intervention and 2,117 to the control group. No difference for any of the study variables was documented between the 2 groups at baseline. About 20% of the children reported intense sun exposure during the year preceding the study. About 88% of the children reported adequate modalities of sun protection. Sunscreens were commonly used. A total of 508 children (12%) reported a history of sunburns in the year preceding the start of the study. Melanocytic naevi were counted in a total of 1,503 children (852 in the experimental and 651 in the control group). No differences in terms of skin, hair and eye colours were documented between the experimental and the control groups. The mean naevus count at baseline was 9.6 (median 7) in the experimental group and 10.1 (median 8) in the control group. Conclusion: About 50% of the total expected number of children was recruited during the pilot phase of the study. Randomization proved to be an excellent modality to select 2 samples similar for all the important study variables examined. A history of sunburns was reported less frequently than expected. The ‘Sole Si Sole No GISED programme’ is one of the few examples of a controlled evaluation of the effectiveness of an educational intervention in Italy.

International audience; Infestation with head lice is a widespread, persistent, and recurring issue leading to serious health problems if untreated. We are facing resistance phenomena to usual pediculicides and questions about their direct or cumulative toxicity. The aim of this trial was to assess the efficacy of a new product, free of chemical insecticides but with a physical effect. This product contains components whose antilice efficacy has already been demonstrated, as well as Andiroba oil which asphyxiates the lice and Quassia vinegar which dissolves the chitin of the nits (they are then inactivated). 30 patients with head lice infestation, aged 3-39 years, applied the treatment one to three times, 5 days apart. Cure was defined as the absence of live lice after 5, 10, or 14 days, and symptoms are usually associated with infestation. Easiness and safety of the treatment were assessed by the patients and/or their parents. Overall cure rates were 20% on D5 after one treatment, 37% on D10 after two treatments, and 90% on D14 after three treatments. Symptoms such as itch, scalp dryness, redness, and flakiness rapidly diminished. This treatment seems to be a beneficial addition or a valuable alternative to existing treatments, considering the total absence of chemical insecticides, the absence of drug-resistance induction in head lice, the absence of major toxicological risks compared with usual pediculicides, and the favourable patient use instructions.

Background Post-menopausal skin aging has intrinsic as well as extrinsic origins, and this process induces important disparities of appearance and feeling within an age range. Objective The objective of this study was to identify 3 grades of maturity of the facial skin of menopausal women. Material and Method One hundred and fifty women aged between 50 and 80 (63 ± 7 years) were enrolled. The investigations combined clinical scoring, biometrological measurements (corneometry, cutometry, digital photography, and 3D analysis by fringe projection), and questionnaires. Images elaborated from photographs and 3D views were scored by 2 investigators to classify the subjects according to 3 grades of skin maturity. Results STEPDISC statistical analysis revealed that the most relevant variables to differentiate the maturity grades were elastosis, wrinkles on the cheeks, wrinkles on the upper lip, roughness, spots, and elasticity. Conclusion The age does not reveal the degree of maturity of mature skin. Three grades of skin maturity in menopausal women, based on clinical and physiological patterns, have been differentiated in this study. Cosmetic treatments specifically adapted to the needs of menopausal women can therefore be developed.

Background: Published studies assessing whether asymmetrical facial ultraviolet light exposure leads to underlying differences in skin physiology and morphology report only clinical observations. The aim of this study was to assess the visual impact on the skin of repeated ultraviolet-A (UVA) exposure through a window. Methods: Eight women and two men presenting with asymmetrical signs of photoaging due to overexposure of one side of their face to the sun through a window over a long period of time were enrolled in the study. Split-face biometrologic assessments were performed (clinical scoring, hydration with Corneometer®, mechanical properties with Cutometer®, transepidermal water loss with AquaFlux®, skin relief with fringe projection, photography, stripping, and then lipid peroxidation analysis). Results: Significant differences were observed in clinical scores for wrinkles, skin roughness assessed by fringe projection on the cheek, and skin heterogeneity assessed with spectrocolorimetry on the cheekbone. Other differences were observed for skin hydration, as well as skin laxity, which tended towards significance. Discussion: This study suggests the potential benefit of daily UVA protection during nondeliberate exposure indoors as well as outside.

Nutritional Components (NC) are often under-estimated by dermatologists who neglect them and patients who do not hesitate to use them without thinking of other parallel medication or consumption. This phenomenon has already led to some incidents, such as chronic hypervitaminosis A following retinoid therapy for aging skin and acne. Consequently, the development of new nutritional components now necessitates safety assessments in order to respond to legal requirements but also to improve the knowledge and confidence of professionals and consumers. These studies have to be associated first with bioavailability studies and in vitro studies to improve the understanding of their mechanisms of action, then with clinical studies to demonstrate their efficacy.

International audience; BACKGROUND/AIMS: The purpose of this work was to develop a new sensor for objective in vivo measurement of the cutaneous temperature based on micro-electro-mechanical systems (MEMS), and to compare these performances with those of a classical thermocouple. Research on this new sensor was carried out to allow the quantification of the thermal properties of the made-up skin. METHODS: Sixteen female subjects divided into two different age groups (18-35 and >50 years old) were recruited for this study. Several zones of the face and forearms were made up at random with foundations containing or not a thermoregulator raw material. The quantity of foundation applied on the skin was standardized and measurements were carried out first before make-up, and then 10 s and 5 min after make-up. The new sensor and the thermocouple were used successively on each zone. The cutaneous temperature was expressed in degrees celsius. RESULTS/CONCLUSION: The two systems are similar in terms of repeatability and reproducibility, with some differences in sensibility. The data measured by the MEMS sensor appear lower than those measured by the thermocouple. After make-up, the MEMS sensor detects a progressive increase of the temperature in time whereas the thermocouple detects a decrease. We found the same evolution on the face but in a more attenuated way. These results tend to show that the devices do not measure the same phenomenon. The thermocouple appears more sensitive to the thermal response of the made-up surface whereas the MEMS sensor appears more sensitive to the heat transfers in the interface between the skin and make-up.

Ultraviolet irradiation causes adverse effects like sunburn, photosensitivity reactions or immunologic suppression. The aim of this study was to evaluate the photo-protective outcome of a sunscreen cream (SPF8) by the determination of erythema indexes and the assessment of ascorbic acid and its metabolites in human dermis. These substances were used as markers of oxidative effect. Eight healthy female subjects were enrolled in this study. Two abdominal areas were exposed to solar simulated irradiation with three minimal erythema dose, one with SPF8 application and the other site without SPF8 application. Two other areas were used as control, one without SPF8 application and the other site after SPF8 application. Ascorbic acid and its metabolites (dehydroascorbic acid, threonic acid, oxalic acid and xylose) were collected from human dermis by microdialysis and assessed by gas chromatography mass spectrometry. Irradiated site without sunscreen application had significantly demonstrated lower dermis ascorbic acid concentrations and a higher erythema index than the three other sites (P < 0.05). Threonic acid, oxalic acid and xylose dermis concentrations were significantly higher in site III than in the control site I (P < 0.05). The protected-irradiated site did not show erythema formation and there was stability of ascorbic acid dermis concentrations with non-variation in its metabolites. The assessment of ascorbic acid and its metabolites in human dermis could be an efficient tool to demonstrate the oxidative process and consequently to control the efficiency of sunscreen creams against undesirable UV effects.

Reactive oxygen species play an important role in inflammatory skin diseases such as psoriasis. Reactive oxygen species synthesis is catalysed by iron and some species are scavenged by ascorbic acid. The aim of this work was to assess iron and ascorbic acid in uninvolved and involved psoriatic dermis and to compare the corresponding concentrations in the dermis of healthy subjects. Microdialysis associated with atomic absorption spectrometry and gas chromatography-mass spectrometry was used to assess iron and ascorbic acid, respectively. Seven psoriatic patients and five healthy volunteers were studied. Iron concentrations in the involved (57.1 +/- 19.3 microg/l) and uninvolved (49.7 +/- 27.1 microgl/l) psoriatic dermis were higher than the corresponding value determined in the dermis of healthy subjects (21.8 +/- 2.4 microg/l) (p