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BACKGROUND Oily skin, characterized by excessive sebum production, can lead to acne and have psychosocial impacts due to changes in appearance. Recent research has shown interest in treatments for oil control, with kaolin and bentonite emerging as promising options. Despite their potential, comprehensive studies on these ingredients are still in the nascent stages. AIM This study aimed to assess the efficacy of a clay mask (La Roche‐Posay Effaclar Sebo‐Controlling Mask) in reducing skin oiliness and acne, and its safety for use. METHODS In this study, 75 adults with oily or combination skin were enrolled and provided with a clay mask for twice‐weekly use over 4 weeks. Clinical assessments, using instruments like Sebumeter, Vapometer, and Corneometer, were conducted at baseline, and after 1, 2, and 4 weeks, evaluating acne lesions, skin irritation, sebum content, and skin hydration. Participant self‐assessment questionnaires were also utilized for subjective evaluation. Statistical analyses were performed accordingly. RESULTS The study revealed significant improvements in acne‐related outcomes, sebum content, skin evenness, stratum corneum water content, and transepidermal water loss following the application of the clay mask. Pore area and porphyrin area showed no significant changes. Tolerance assessment showed reduced dryness and irritation, with self‐assessment indicating high product acceptability and perceived oil control effectiveness. CONCLUSION This study demonstrated the clay mask's efficacy in managing acne and oily skin, improving hydration and texture. Significant improvements in skin parameters and high product safety were observed, supporting its suitability.
Background Evidence suggests that sebum content is important in skin disorders such as acne. However, sebum levels change depending on the external environment, and quantifying skin sebum levels is challenging. Here, we propose an optimal method for quantifying the facial sebum level. Materials and methods Four hundred and sixty participants (160 males and 300 females) aged 20–40 were enrolled in this study. A Sebumeter SM 810 was used to measure the sebum level at five facial locations: the forehead, the chin, the left cheek, the right cheek, and the nose. The participants were divided into two groups; one group underwent a one‐time measurement ( n = 390, male: female = 120: 270), and the other underwent three consecutive measurements ( n = 70, male: female = 40: 30). The casual sebum level (CSL) was measured in all patients after a 30‐min acclimatization; subsequently, the sebum removal process was conducted, followed by a resting period of 1 h to determine the sebum excretion rate (SER). Spearman's correlation analysis and the Wilcoxon signed‐rank test were used to compare the sebum level consistency and differences between the groups. Results Although three consecutive measurements better reflected the sebum content, the one‐time measurement also represented the relative sebum level. One hour after sebum removal, the sebum level recovered to 70%–90%; thus, this method was applicable for use in SER quantification. Of the five testing points, the sebum content was highest in the nose and lowest in the cheeks (both left and right). In addition, the cheeks were the most stable sites in terms of testing points, testing times, and CSL/SER values. A one‐time measurement of the CSL could represent the SER 1 h after the sebum removal. In our cohort, the sebum level of males with oily skin was decreased at age 32–35, and that of males with non‐oily skin increased at 28–35. The opposite trend was observed in female participants. Conclusion Sebum measurement methods were assessed, including testing times, indices (interval of time) and sites in a conditioned external environment. A one‐time measurement of the CSL 1 h after sebum removal was sufficient to determine the sebum level and SER, and the cheeks are recommended as the testing site. Sex and skin type differences were observed in sebum level changes with age.
Background: The decline in estrogen levels from several years before (perimenopause) and during menopause has various negative effects, including skin specific issues, which often receive less attention than other menopausal symptoms despite having a significant negative effect on quality of life (QoL). The objective of this study was to evaluate the effectiveness of anti-aging dermocosmetic products designed for women during the perimenopause and menopause. Materials and methods: An open study of 101 perimenopausal women (no menstruation for 4-12 months or irregular menstruation for <5 years) and 101 menopausal women (no menstruation for >12 months), not taking hormone replacement therapy, was conducted. Adapted dermocosmetic regimens, specific to each group (day cream, night cream and serum), were applied for 56 days. Assessments included automatic artificial intelligence diagnostics of eight clinical facial signs, hydration and transepidermal water loss (TEWL), and a menopause skin QoL questionnaire. Results: Mean age was 50 ± 3.9 years (range 41-57) and 59 ± 3.8 years (range 50-66) for the perimenopause and menopause groups, respectively. Significant improvements in wrinkles and vascular signs, increases in hydration, decreases in TEWL, and a positive impact on QoL were observed after 56 days of application of the respective dermocosmetic regimens for both the perimenopause and menopause groups. Conclusion: The anti-aging skin care products designed specifically for perimenopausal and menopausal women increased skin hydration and improved wrinkles with a positive impact on QoL.
Background: Data reflecting the impact of photo-protection on cutaneous aging are scarce and mostly limited to fair skin. Objective: To assess, the effectiveness of a photoprotective product in counteracting the photoaging process in different skin phototypes over one year compared against a classical routine. Material and methods: 290 Brazilian women aged 30-65 years, with skin phototype II to VI were equally randomized in two groups. Group 1 kept on their routine whereas Group 2 applied, twice daily, a photoprotective product (SPF 60, PPD=24.1) replacing the one they routinely used. Volunteers reported the duration of their daily sun-exposure. Standardized photographs taken at D0 and D365 were analyzed by 15 dermatologists to assess 8 wrinkles and pigmentation signs. Results: A global increase in severity was reported which was significant for Group 1. This increase was lower in Group 2 where only half the signs showed significant worsening. In Group 2 versus Group 1, the increase in Forehead wrinkles, Marionette lines, Wrinkles created by ptosis and Size of dark spot, was significantly (p< 0.05) decreased by 30-50%. Conclusion: Daily application of a high photoprotective product significantly decreases the progression of skin aging signs after one year in skin phototypes II to VI.
Objective: To evaluate the capacity of the automatic detection system to accurately grade, from selfie pictures, the severity of eight facial signs in South African men. Methods: Selfie pictures (obtained from frontal and back cameras) of 281 South African men differently aged (20-70 years) were obtained and analyzed by an automatic artificial intelligence (AI)-based automatic grading system. Data were compared with the clinical gradings made by experts and dermatologists. Results: In all facial signs, both series of gradings were found highly correlated with, however, different coefficients (0.59-0.95), those of marionette lines and cheek pores being of lower values. No differences were observed between data obtained by frontal and back cameras. With age, in most cases, gradings show up to the 50-59 year age-class, linear-like changes. When compared to men of other ancestries, South African men present lower wrinkles/texture, pigmentation, and ptosis/sagging scores till 50-59 years, albeit not much different in the cheek pores sign. The early onset (mean age) of visibility of wrinkles/texture for South African men were (i.e., reaching grade >1) 39 and 45 years for ptosis/sagging. Conclusion: This study completes and enlarges the previous works conducted on men of other ancestries by showing some South African specificities and slight differences with men of comparable phototypes (Afro American).
Plant metabolic profiling can provide a wealth of information regarding the biochemical status of the organism, but sample acquisition typically requires an invasive and/or destructive extraction process. Reverse iontophoresis (RI) imposes a small electric field across a biological membrane to substantially enhance the transport of charged and polar compounds and has been employed, in particular, to extract biomarkers of interest across human skin. The objective of this work was to examine the capability of RI to sample phytochemicals in a minimally invasive fashion in fructo (i.e., from the intact fruit). RI was principally used to extract a model, bioactive compound - specifically, ellagic acid - from the fruit peel of Punica granatum L. The RI sampling protocol was refined using isolated peel, and a number of experimental factors were examined and optimised, including preparation of the peel samples, the current intensity applied and the pH of the medium into which samples were collected. The most favourable conditions (3 mA current for a period of 1 hour, into a buffer at pH 7.4) were then applied to the successful RI extraction of ellagic acid from intact pomegranates. Multiple additional phytochemicals were also extracted and identified by liquid chromatography with tandem mass spectrometry (LC-MS/MS). A successful proof-of-concept has been achieved, demonstrating the capability to non-destructively extract phytochemicals of interest from intact fruit.
Background: Inflammatory and non-inflammatory acne lesions constitute a significant clinical challenge in acne subjects. Aim: To evaluate the efficacy and safety of a facial serum and a mask containing salicylic acid and lipohydroxy acid for improving skin conditions. Methods: This randomized controlled trial included adults with comedones, post-inflammatory erythema (PIE) and/or hyperpigmentation (PIH) in Shanghai, China in July 2021. Participants were randomly assigned 1:1 to receive the study Serum + Mask or serum alone for 8 weeks. Acne severity, comedones, papules, pustules, PIE, PIH, skin pores, skin tone evenness, sebum secretion, skin hydration, and trans-epidermal water loss were evaluated at T0d, T1d, T7d, T14d, T28d, and T56d. Results: Eighty-three participants were included, including 41 and 42 in the Serum + Mask and Serum groups, respectively. Acne severity, density of skin pores, skin tone evenness, PIH foci on face, PIE foci on nose, intensity of PIE and PIH, closed comedones on face, open comedones on nose, sebum secretion, and skin hydration were significantly improved from baseline after 8 weeks of treatment in both groups (all p < 0.05). Addition of the mask improved the number of closed comedones (-6.56 ± 0.39 vs. -5.19 ± 0.44, p = 0.022) and acne severity (-0.39 ± 0.08 vs. -0.12 ± 0.09, p = 0.026) substantially more than using the serum alone. No adverse reaction was reported in either group. Conclusions: The study serum improved skin conditions by regulating skin barrier function and achieving a balance of skin hydration and sebum secretion, removing comedones and improving PIE and PIH. Addition of the mask accelerated the effects without compromising safety.
Introduction: Scalp psoriasis frequently goes with other disease location and may lead to a significant burden and impairment of quality of life (QoL). Adherence to local treatments is a frequent problem. A keratolytic and hydrating shampoo containing 2% salicylic acid, 5% urea, and 1% glycerin (active shampoo) has been developed for psoriasis-prone scalp. Objective: To assess the efficacy and tolerability of an active shampoo in subjects with mild to moderate scalp psoriasis. Materials and methods: A single-center, randomized, double-blind, vehicle-controlled study was conducted on 67 adults with mild to moderate psoriasis. The active shampoo or its vehicle were applied daily for 14 days and 3 times/week for another 14 days. Assessments included the Psoriasis Scalp Severity Index (PSSI), Investigator Global Assessment (IGA), calculated total surface affected hair, scalp greasiness, irritation, and assessed scalp dermatitis-specific quality-of-life issues using SCALPDEX and product acceptability. Results: The active shampoo significantly (p < 0.05) reduced the PSSI by 39.0%, 37.2%, 63.0%, and 69.0% immediately after washing compared to a 22.8%, 5.5%, 19.6%, and 13.0% with the vehicle at Days 1, 8, 15, and 30, respectively. SCALPDEX items, IGA, and irritation significantly (p < 0.05) reduced with the active shampoo. Hair and scalp greasiness improved continuously with both products until Day 21. Subject-reported symptom scores paralleled the positive evolution of clinical signs. The active shampoo was well tolerated, subjects were highly satisfied and had an improved QoL. Conclusion: The active shampoo significantly improved clinical signs, symptoms, and QoL of mild-to-moderate scalp psoriasis compared to the vehicle. It was very well tolerated and highly appreciated by the subjects.
Background: Facial wrinkles are clear markers of the aging process, being chronological, photo-induced, or reflecting repetitive facial expressions. The aim of this study is to provide new insights into the biophysical and biological mechanisms involved in the formation, prevention, or elimination of the expression wrinkles. Materials and methods: We use a computational model to get a better understanding of the wrinkle mechanical behavior and evolution after skin softening and suggesting a possible antiaging mechanism. Then, we provide a clinical demonstration of the anti-wrinkle effect of a long-term application of a 20% glycerol in a moisturizer formula (GBM) versus its vehicle on crow's feet. Skin hydration, elasticity, and wrinkles visibility were evaluated by a combination of clinical and instrumental in vivo data, inverse finite element analysis, and proteomic data. Results: The computational model shows a predominantly compressive stress beneath the wrinkle and its significant decrease by the softening of stratum corneum. The associated clinical study confirmed a significant increase of skin hydration and elasticity as well as a decrease of wrinkle visibility after 2 and 4 months as application for both formulas; this effect being stronger for GBM. A softening effect on stratum corneum and dermis was also observed for the GBM. Furthermore, proteomic data revealed an effect of upregulation of four proteins associated with desquamation, cell-glycan extracellular interactions, and protein glycation/oxidation, functions related to the tissue mechanics and adhesion. Conclusions: We provide an in vivo demonstration of the anti-ageing benefit of glycerol at high dose (20%) reflected by a cumulative skin surface softening effect. The use of high moisturizing potent formulations should bring additional performance to other conventional moisturizing formulations.
Background: Aging signs are much visible on the surface of the skin that presents different changes: cheeks start to sag, more and deeper wrinkles appear, and pigmentation spots increase. Face diagnostic to recommend products includes assessing cutaneous micro-relief or the micro-depressive network on the face. Furthermore, there is an increasing demand for clinical and instrumental methods to prove the efficacy of anti-aging treatments. As a result, very accurate and sensitive three-dimensional (3D) devices are developed and validated to measure and quantify aging skin and to catch fine anti-aging products acting on wrinkles and fine lines. Methods: AEVA-HE, a non-invasive 3D method based on fringe projection technology, is used to robustly characterize the skin micro-relief from a full-face acquisition and from multiple extracted zones of interest. In vitro and in vivo studies are conducted to assess the reproducibility of this system and its precision toward a standard fringe projection system, DermaTOP. Results: The AEVA-HE successfully measured micro-relief and wrinkles and demonstrated the reproducibility of measurements. AEVA-HE parameters were found highly correlated to DermaTOP. Conclusion: The present work illustrates the performance of the AEVA-HE device and its dedicated software kit as a precious tool for quantifying the major characteristics of wrinkles appearing with age and thus offers a high potential for assessing the effect of anti-wrinkling products.
Objective: This study describes the development and characterization of a novel in vitro wound-healing model based on a full-thickness reconstructed skin by exposing the tissue to fractional ablative laser treatment. Method: A 3D full-thickness skin model was fabricated and treated with fractional ablative CO2 laser. Wound-healing process was characterized by HE staining, noninvasive OCT imaging, immunostaining, as well as transepidermal water loss measurement. Cytokines and proteins involved in the inflammatory and dermal remodeling process were studied by ELISA and protein array assays. Results: Fractional ablative CO2 treatment induced a wound zone of 9 mm in diameter, containing 56 micro-wounds with 200 μm diameter and 500-700 μm in depth on reconstructed full-thickness skin model. HE staining revealed a typical wound morphology and healing process with migration of keratinocytes, formation and extrusion of necrotic tissue, and cell inclusion in dermis, which correlates with clinical observations. Based on OCT and TEWL measurements, the re-epithelialization took place over 2 days. Laser-triggered keratinocytes proliferation and differentiation were demonstrated by activated Ki67 and Filaggrin expression respectively. Injury-invoked cytokine ICAM-1 showed instant upregulation on Day 1. Decreased epidermis thickness and depression of IGFBP-2 protein level synergistically indicated the unavoidable thermal side effects from laser treatment. Downregulated DKK-1 protein level and upregulation of α-SMA together implicated the risk of potential fibrosis post-laser treatment. Conclusion: This in vitro laser wounded reconstructed skin model captured the key events of wound-healing process, could be used to investigate the mechanisms of wound-healing triggered by a commonly used beauty procedure, and also provides a valuable tool for evaluating the efficacy of novel actives for the post-procedure application.
Objective: Based on in vivo data, in vitro models and new methods are created to mimic the impact of aerial pollution onto the hair surface and assess the efficacy of different formulae prototypes. Material and methods: Two protocols are developed to mimic the pollution effect, in vitro, on purchased swatches, and in vivo, on scalps and forearms. First, with an artificial sebum mixed with Carbon Black particles, named "sebollution," we evaluated, through an instrumental color measurement, the cleansing efficacy of some shampoo on scalp and hair. The second protocol allowed to assess the interaction between hair care product deposit (shampoo, conditioner, mask, and leave-on) on hair and carbon black particles spread on fiber. The quantification of particle coverage allowed to evaluate the efficiency of a formula to limit the aerial pollution deposit on hair fiber. Results: To simplify and accelerate the evaluation of 42 shampoo formulae, an extrapolation of the scalp cleaning process was validated on forearm. The respective cleanabilities were calculated and covered a large range of efficacy, from 5%, for a basic bland shampoo generally used to reset swatches, to a strong deep cleansing efficacy of 100%. On hair swatches, cleanability efficiencies of five shampoo were also evaluated to eliminate the deposited of sebollution, in a range of 40%-80%. To quantify the efficacy of preventing the deposition of carbon particle on hair surface, the percentage of coverage of 45 different products was measured, from 2% to 16%. The performance depended of the product category (shampoo, conditioner, mask, and leave-on), driven by the performance of the product deposit, and the capacity of this deposit to interact with aerial pollution. Conclusion: Three new protocols and evaluation methods are proposed to evaluate and quantify the performance of hair care product, to remove/clean, limit, and protect the hair fibers against the aerial pollution that could interact with hair, scalp and sebum. The validation of these approaches was done through the testing of a large panel of hair care product leading to a complete and sincere evaluation of cleansing and anti-deposit efficacy. Combining the knowledge acquired on pollution impact on hair and the development of specific way of evaluation, this work reinforced the rationale of using and developing new cosmetic products that reduced the impact of pollution upon some hair properties.
Objective: The objective of the study was to assess in vivo the validity of a new imaging device in quantifying the scarring process over time and to compare its data with the expertise of dermatologist and patients' self-appraisals. Materials and methods: A total of 37 Korean women, aged 20-50 year, with closed scars of different types, were enrolled after a dermatological evaluation. All subjects applied daily a hydrating cream on their scars for 2 months. Images of scars at different times (Day 0, Day 28, and Day 56) were taken and further analyzed, yielding various parameters such as color, luminance, size, volume, and depth of each scar. A dermatologist visually graded, at each time point, the clinical aspect of the scar, and patients were asked to answer to some questions dealing with their self-examination of their scar. Results: The changes in some scar features that occurred during the application period were quantified and statistically differed from the D0 baseline value. Scars became of reduced size, lighter (Increased luminance), less red, less deep, and less voluminous. Some of these parameters (volume, lightness, smoothness, texture regularity) were statistically different at D28 whereas some others (area, depth, redness) showed significant changes at D56 . Dermatologist expertise and patients' assessments were in high agreement. Conclusion: This methodological approach that uses a dedicated camera associated with image analysis, despite some inherent limits (size of the scar), appears as a valuable aid to surgeons in the management of scars, in the follow-up of a given procedure or treatment. Beyond scar management, this approach may be extended to other skin disorders such as acne.
Cell counting is an important step in many biological experiments. Itcan be challenging, due to the large variability in contrast and shapeof the cells, especially when their density is so high that the cellsare closely packed together. Automation is needed to increase thespeed and quality of the detection. In this study, a cell countingmethod is developed for images of melanocytes obtained afterfluorescent labelling with TRP1 (Tyrosinase-related protein 1) of 3Dreconstructed skin samples. Following previous approaches, a strategybased on predicting the local cell density, by means of aconvolutional neural network (a U-Net), was adopted. The methodshowed great efficiency on a test set of 76 images, with an assessedcounting error close to 10% on average, which is a commonly acceptedtarget in cytology and histology. For comparison purposes, we havemade our dataset publicly availableCell counting is an important stepin many biological experiments. It can be challenging, due to thelarge variability in contrast and shape of the cells, especially whentheir density is so high that the cells are closely packedtogether. Automation is needed to increase the speed and quality ofthe detection. In this study, a cell counting method is developed forimages of melanocytes obtained after fluorescent labelling with TRP1(Tyrosinase-related protein 1) of 3D reconstructed skinsamples. Following previous approaches, a strategy based on predictingthe local cell density, by means of a convolutional neural network (aU-Net), was adopted. The method showed great efficiency on a test setof 76 images, with an assessed counting error close to 10% on average,which is a commonly accepted target in cytology and histology. Forcomparison purposes, we have made our dataset publicly available
Background: Skin aging goes beyond a chronological process and also results from extrinsic factors referred to as the exposome. Hyaluronic acid (HA) is an important component of the extracellular matrix, with loss starting at 25 years old. While many studies of HA concern topical use, few literature reviews only address the use of topical HA in dermatology. Objective: This review describes the different characteristics of HA-containing cosmeceuticals, with a focus on skin aging and the impact of exposome factors on HA synthesis and degradation. Methods: A review was performed using the terms hyaluronic acid, hyaluronan, topical, dermatology, cosmetic, aging treatment, exposome, and cosmeceuticals. Results are also presented from a recent randomized controlled trial (RCT), which investigated the additional benefit of using a HA epidermic filler (HA-filler serum) combined with Botulinum toxin type A (BoNTA) to treat signs of skin aging. Subjects were randomized to two groups: HA-filler serum starting 24 hours after the BoNTA injection then twice daily for 24 weeks, or the control group which received BoNTA. Results: HA is a key ingredient used in cosmeceuticals for its hydration/antiaging properties (hygroscopic, rheological, and viscoelastic). Several clinical studies indicate that HA is both well tolerated and effective, adjuvant to both post-surgical and facial rejuvenation procedures. In the RCT, one of few studies to combine BoNTA and HA with a 6-month follow-up, the HA-filler serum lengthened the duration of BoNTA's effect in reducing wrinkles. Conclusions: Numerous studies support HA-based cosmeceuticals as a non-invasive, effective solution for improving skin hydration and rejuvenation. This article is protected by copyright. All rights reserved.
Background: Real-life validation is necessary to ensure our artificial intelligence (AI) skin diagnostic tool is inclusive across a diverse and representative US population of various ages, ancestries and skin phototypes. Objectives: To explore the relevance and accuracy of an automated, algorithm-based analysis of facial signs in representative women of different ancestries, ages and phototypes, living in the same country. Methods: In a cross-sectional study of selfie images of 1041 US women, algorithm-based analyses of seven facial signs were automatically graded by an AI-based algorithm and by 50 US dermatologists of various profiles (age, gender, ancestry, geographical location). For automated analysis and dermatologist assessment, the same referential skin atlas was used to standardize the grading scales. The average values and their variability were compared with respect to age, ancestry and phototype. Results: For five signs, the grading obtained by the automated system were strongly correlated with dermatologists' assessments (r ≥ 0.75); cheek skin pores were moderately correlated (r = 0.63) and pigmentation signs, especially for the darkest skin tones, were weakly correlated (r = 0.40) to the dermatologist assessments. Age and ancestry had no effect on the correlations. In many cases, the automated system performed better than the dermatologist-assessed clinical grading due to 0.3-0.5 grading unit differences among the dermatologist panel that were not related to any individual characteristic (e.g. gender, age, ancestry, location). The use of phototypes, as discontinuous categorical variables, is likely a limiting factor in the assessments of grading, whether obtained by automated analysis or clinical assessment of the images. Conclusions: The AI-based automatic procedure is accurate and clinically relevant for analysing facial signs in a diverse and inclusive population of US women, as confirmed by a diverse panel of dermatologists, although skin tone requires further improvement.
Background Chronic sun exposure induces skin damage leading to skin ageing and skin colour heterogeneity with hyperpigmented spots. In this process ultra violet A (UVA) rays highly contribute, especially long-UVA (UVA1) supporting the need for an efficient photoprotection over the whole UV spectrum. A new UVA1 filter, methoxypropylamino cyclohexenylidene ethoxyethylcyanoacetate (MCE), with a pic of absorption at 385 nm, has been recently approved for use in sunscreen products. Objective Three randomised clinical studies were performed to evaluate the additional photoprotection afforded by a sunscreen formula containing MCE compared to state-of-the-art sunscreen lacking absorption in the longest UVA1 wavelengths. Two studies were performed on European volunteers with UV-controlled (UVA1, ultra violet B (UVB) + UVA) exposures and one on Indian volunteers under real sun exposures. Methods Three intraindividual trials (two randomised UV-controlled and one real sun) were conducted on a total of 62 healthy subjects with Fitzpatrick III–IV and individual typology angle (ITA°) values between −18° and 35°. The MCE at 2% was formulated in a state-of-the-art sun protection factor 30 sunscreen reference allowing to enlarge the absorption profile up to 400 nm. UV-induced pigmentation was assessed by colorimetric measures and visual scoring at different time points after a single exposure to UVA1 (Study 1) or repeated exposures to daily UV radiation comprising both UVB and UVA (Study 2) or under real sun (Study 3). Results Whatever the study exposure condition (UVA1, UVB + UVA, real sun), the level of pigmentation was increased as attested by colorimetric parameters (decreased luminance L* and ITA° values) and visual scorings. In the three studies, the comparison showed higher prevention of hyperpigmentation with the sunscreen enlarged in the longest UVA1 wavelengths with MCE compared to the state-of-the-art sunscreen. No side effects were reported. Conclusions MCE is a valuable UVA1 filter to improve photoprotection over the entire UV spectrum in state-of-the-art sunscreens and limits the impact of UVA1 rays.
Background: Color imaging is a tried and true method for the evaluation of cosmetic and dermatological effects, but it fails to capture all the information in a scene's spectral reflectance. For this reason, there has been in recent years increasing interest in the use of imaging spectrometers for clinical studies and product evaluation. Material and methods: We developed a novel HyperSpectral Imager (HSI) able to take in vivo full-face format images as a next generation instrument for skin color measurement and beyond. Here, we report part of the results of our first full-scale validation test of the HSI. We replicated a make-up foundation screening test by applying three products to a panel of 9 models and evaluated the product L∗ , a∗ , b∗ , and ∆E effect immediately after application relative to the bare skin condition. We repeated this test twice in order to study the repeatability of the HSI as an evaluation instrument and during each test two different operators duplicated the data acquisition so we can assess the reproducibility of the measurements. Results: We find that the measurements from the HSI provide repeatability and reproducibility as good or better than those of our previous benchmark devices. Conclusion: From these results, we conclude that not only is the HSI suitable for use in color evaluation studies, but also that it gives operational advantages over the previous generation of evaluation instruments, as it provides a spectral measurement combined with good spatial resolution. This allows for analysis of color over an area and post hoc selection of study regions and so opens new possibilities for studies of complex in vivo phenomena which neither non-imaging spectrometers nor conventional cameras can pursue. This study also raises points for future work concerning proper inclusion of instrument uncertainty in comparisons of results between instruments and handling of systematic uncertainties from analyses based on a single area.
Objective: To evaluate the capacity of the automatic detection system to accurately grade, from smartphones' selfie pictures, the severity of fifteen facial signs in South African women and their changes related to age and sun-exposure habits. Methods: A two-steps approach was conducted based on self-taken selfie images. At first, to assess on 306 South African women (20-69 years) enrolled in Pretoria area (25.74°S, 28.22°E), age changes on fifteen facial signs measured by an artificial intelligence (AI)-based automatic grading system previously validated by experts/dermatologists. Second, as these South African panelists were recruited according to their usual behavior toward sun-exposure, that is, nonsun-phobic (NSP, N = 151) and sun-phobic (SP, N = 155) and through their regular and early use of a photo-protective product, to characterize the facial photo-damages. Results: (1) The automatic scores showed significant changes with age, by decade, of sagging and wrinkles/texture (p < 0.05) after 20 and 30 years, respectively. Pigmentation cluster scores presented no significant changes with age whereas cheek skin pores enlarged at a low extent with two plateaus at thirties and fifties. (2) After 60 years, a significantly increased severity of wrinkles/texture and sagging was observed in NSP versus SP women (p < 0.05). A trend of an increased pigmentation of the eye contour (p = 0.06) was observed after 50 years. Conclusion: This work illustrates specific impacts of aging and sun-exposures on facial signs of South African women, when compared to previous experiments conducted in Europe or East Asia. Results significantly confirm the importance of sun-avoidance coupled with photo-protective measures to avoid long-term skin damages. In inclusive epidemiological studies that aim at investigating large human panels in very different contexts, the AI-based system offers a fast, affordable and confidential approach in the detection and quantification of facial signs and their dependency with ages, environments, and lifestyles.
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Vijaykumar Patra
  • Research and Innovation
Matthieu Perrot
  • Research and Development
Bruno A Bernard
  • Research & innovation, Scientific Directorate
Gustavo S Luengo
  • Research and Development
Paris, France