Photoaging's portrait: The road map towards its photoprotection.

Objective: To summarize key research published by the author's group, dealing with skin photoaging and its photoprotection.

Materials And Methods: Two methodologies (standard photographs and selfies imaging) resulting from referential skin ageing atlases were applied on 2487 subjects of different ancestries, ages and gender. These aimed at first to best assess and grade the variable severities of some facial signs (texture/wrinkles, pigmentary spots, sagging and vascular disorders) that occur progressively during the photoaging process.

Structural and functional age-related changes in some facial signs of Chinese men: A pilot study.

Objective: The objective of the study was to associate, on the same Chinese male subjects, changes in facial ageing signs with some biomechanical skin properties.

Methods: The severities of 20 facial ageing signs of 219 differently aged Chinese men (20-65 years) were graded in blind by trained experts through standardized photographs, using a referential skin Atlas dedicated to Asian men. On each subject, the mechanical properties were assessed on the cheek area (left or right at random) by the validated suction technique Cutometer®.

Age-related changes to characteristics of the human eyes in women from six different ethnicities.

Background: To describe some morphological characteristics of the eyes of women of 6 different ethnicities and ages.

Material & Methods: Standard digital photographs of 3600 women of different ethnicities and ages were taken for evaluating the effects of some makeup products (eyeliners, mascaras, eyelids makeup, etc) through a before/after comparison. Photographs corresponding to pre-applications offered opportunity to quantify, through image analysis, some features of the human eyes (height, length, ellipticity, horizontality, etc) for recording their possible variations linked to ethnicities and/or age.

Immunohistochemical patterns in the interfollicular Caucasian scalps: influences of age, gender, and alopecia.

Skin ageing and gender influences on the scalp have been seldom studied. We revisited the changes in the interfollicular scalp. The study was performed on a population of 650 volunteers (300 women and 350 men) for over 7 years.

Seasonal skin darkening in Chinese women: the Shanghaiese experience of daily sun protection.

The facial skin tone of two groups of Chinese women from Shanghai was compared using standard colorimetric space techniques during a 6-month interval between January and July 2011. During the study period, one group of women (n = 40) applied a potent sun-protective cosmetic product daily, while the other group (n = 40) did not use any sun protection. The results, based on images taken using a standardized digital camera coupled to a spectroradiometer, showed that sun protection largely mitigated changes in the components of skin tone, ie, lightness, melanization, and individual typology angle parameters.

Chemical stability and degradation mechanisms of ferulic acid (F.A) within various cosmetic formulations.

Ferulic acid (F.A) receives significant interest in the beauty industry with regard to its skin-whitening and anti-oxidant properties. However, its use in cosmetics is limited due to pH- and temperature-related instabilities.

Shape variability and classification of human hair: a worldwide approach.

Human hair has been commonly classified according to three conventional ethnic human subgroups, that is, African, Asian, and European. Such broad classification hardly accounts for the high complexity of human biological diversity, resulting from both multiple and past or recent mixed origins. The research reported here is intended to develop a more factual and scientific approach based on physical features of human hair.

Worldwide diversity of hair curliness: a new method of assessment.

Background: For many years, cosmetic scientists have attempted to measure the physical features of human hair, such as its shape and colour, as these can be artificially modified using cosmetic products. With regard to hair shape, previous anthropologic studies have emphasized its variability within and between human ethnic groups. Many studies have broadly distinguished three ethnic human subgroups: African, Asian, and Caucasian.

The use of hydroxy acids on the skin: characteristics of C8-lipohydroxy acid.

The hydroxy acids are widely used in skin creams because of their exfoliating and rejuvenating effect on photoaged skin. As a member of this family, the salicylic acid derivative known in the literature as 2-hydroxy-5-octanoyl benzoic acid or beta-lipohydroxy acid has also been proposed as an exfoliant and as a treatment of photoaged skin and acne. This article reviews the effects of the hydroxy acids and compares them to those of the salicylic acid derivative.

Skin capacitance imaging and corneosurfametry. A comparative assessment of the impact of surfactants on stratum corneum.

Silicon image sensor (SIS) technology was recently introduced as an innovative tool (SkinChip, L'Oréal) providing sensitive imaging of the skin capacitance. This method can detect discrete focal variations in skin surface hydration, and thus early discrete manifestations of skin irritation induced by surfactants. In the present in vivo study, 2 neat and diluted shampoos, and 5% and 10% sodium laurylsulfate solutions were tested on human skin.

Subclinical speckled perifollicular melanosis of the scalp.

Based on the clinical presentation of some skin pigmentation disorders it is thought that a bicompartmental functional system exists in the epidermal melanocyte population. It corresponds to the perifollicular and interfollicular compartments, respectively. The present study was undertaken looking for the presence of such a system on scalp unaffected by pigmentary disorders.