Rosacea is associated with conjoined interactions between physical barrier of the skin and microorganisms: A pilot study.

BACKGROUND: Rosacea is a common condition characterized by transient or persistent central facial erythema, and often papules and pustules. Currently, the role of bacterium in the development and progression of rosacea remains controversial. This study aimed to investigate the difference in the physiological conditions and microorganisms between the lesional and non-lesional areas of papulopustular rosacea. METHODS: Twenty-five French patients with papulopustular rosacea were enrolled in this pilot study. Each patient was subjected to clinical assessment, and the skin barrier function was tested in lesional and non-lesional areas. In addition, samples from the lesional and non-lesional areas were collected for bacterial culturing. RESULTS: Of all subjects included in the study, a lower skin conductivity was measured in lesional areas than in non-lesional areas (43.5 ± 12.4 vs. 57.2 ± 11.6 U, P < .05), and a higher transepidermal water loss (TEWL) value was found in lesional areas than in non-lesional areas (17.2 ± 5.9 vs. 14.2 ± 4.1 g/(m2  h), P < .05). We found a lower TEWL in lesions in rosacea patients with bacterial dysbiosis than in those with bacterial balance (P < .05). In addition, there were significant differences in the skin conductivity and TEWL between lesional and non-lesional areas in patients with bacterial dysbiosis (P < .001), and no significant differences were seen in patients with bacterial balance (P < .05). CONCLUSION: The results of the present study demonstrate that the physiological features of rosacea are closely associated with the interactions between the host and the microorganisms.

Identification Of Three Key Factors Contributing To The Aetiology Of Dark Circles By Clinical And Instrumental Assessments Of The Infraorbital Region.

BACKGROUND: 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.

Efficacy of micronutrient supplementation on skin aging and seasonal variation: a randomized, placebo-controlled, double-blind study.

BACKGROUND: Several studies have confirmed dramatic changes in skin surface parameters during the winter months. Although there are many studies supporting the positive effects of topical treatment, there are no published studies demonstrating the effects of oral supplementation in the prevention of negative skin changes during winter. The purpose of this study was to evaluate the efficacy of an oral micronutrient supplement in preventing the negative effects of winter weather on skin quality using noninvasive biometrologic instruments. METHODS: This study included 80 healthy female volunteers aged 35-55 years with phototype II-IV skin. Randomization was balanced. Two tablets of a micronutrient supplement (Perfectil® Platinum) or placebo were administered once daily for 4 months. The volunteers were examined at baseline, after 4 months, and 6 weeks after termination of treatment (month 5.5). The evaluation included skin microrelief by Visioscan® as the main outcome, and the secondary outcomes were results on standard macrophotography, skin tension by Reviscometer®, skin high-frequency ultrasound, and self-assessment. RESULTS: For all pseudoroughness and microrelief indicators, there was a significant increase from baseline to month 4 in the placebo group (P<0.05) but no change in the active group. Descriptive statistics for the mean minimum, mean maximum, and minimum to maximum ratio on the nonexposed study zone showed a significant and dramatic difference between baseline and month 4 and between baseline and month 5.5 (P<0.05) in the active group, indicating decreasing anisotropy of the skin. High-frequency ultrasound on the exposed study zone revealed that skin thickness was significantly decreased in the placebo group during winter but was stable in the treated group (P<0.01). The photography scaling and self-assessment questionnaire revealed no significant changes in either group. CONCLUSION: These results indicate that the skin is prone to seasonal changes during winter, particularly in exposed areas. The data also indicate that oral supplementation can be a safe treatment, with no serious side effects, and may prevent or even eliminate the negative effects of winter on the skin.

Exploratory study of the typology of various grades of mature skin.

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.

Assessment of the efficacy and safety of a new treatment for head lice.

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.

Assessment of cumulative exposure to UVA through the study of asymmetrical facial skin aging.

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.

Clinical, biometric and structural evaluation of the long-term effects of a topical treatment with ascorbic acid and madecassoside in photoaged human skin.

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.

Skin radiance: how to quantify? Validation of an optical method.

BACKGROUND/PURPOSE: The aim of this study was to validate an optic device used to measure the quantity of light reflected by the skin, which depends on the brightness of the skin. METHODS: This apparatus gives three parameters, called Complexion/diffusion (Cd), Cr (Complexion/reflection) and Complexion/specular position (Csp). Measurements were carried out on the forehead (slightly rounded surface) and the cheekbone (angular surface). To estimate the repeatability and the reproducibility of each parameter, two female subjects (one with a dull complexion and the other with a glowing complexion) and three operators participated in the study. To investigate repeatability, each operator performed 10 consecutive measurements on both zones. To investigate inter-investigator reproducibility, the operators performed the measurements alternately. To investigate day-to-day reproducibility, these measures were achieved during three visits at a 2-day interval, at D1, D3 and D5. To estimate the sensitivity and the specificity, 30 females participated in the study (15 in the dull complexion group and 15 in the glowing complexion group). RESULTS: Cd was repeatable (variation coefficient <20%), day-to-day reproducible on both sites (generally P>0.05) but not inter-investigators reproducible (generally P<0.05). The sensitivity was 93% on the forehead and 80% on the cheekbone; the specificity was 87% on the forehead and 60% on the cheekbone. Cr was repeatable (variation coefficient <5%), day-to-day reproducible (P>0.05) and not inter-investigators reproducible (generally P<0.05). The sensitivity was 93% on the forehead and 80% on the cheekbone; the specificity was 87% on the forehead and 80% on the cheekbone. Csp was not repeatable (variation coefficient >5%) on both the studied zones and for the three investigators. CONCLUSION: The repeatability and the day-to-day reproducibility were satisfying for the Cd and Cr parameters on both the studied sites. The sensitivity and the specificity were satisfying for both parameters on both sites, except for the specificity of the Cd parameter on the cheekbone. Therefore, this apparatus is suitable to follow-up an evolution on both the studied sites, but we recommend: (a) that the same trained investigator always performs the measurements, (b) to privilege the forehead in particular for a classification (dull or glowing).

Development of a new sensor based on micro-electro-mechanical systems for objective in vivo measurement of the cutaneous temperature: application to foundations.

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.

Age-related changes of the cutaneous microcirculation in vivo.

BACKGROUND: The architectural frameworks of the skin microcirculation are rather complex and change continuously with aging. But these changes are yet poorly documented in vivo. OBJECTIVES: Using non-invasive methods belonging to the field of biometrology, the study aimed to investigate quantitatively the changes of the cutaneous microvasculature in different anatomic sites with age. METHODS: Measurements were performed on crow's feet, forehead, volar forearm and dorsum of hand in 50 women (aged 20-74 years who consisted of 10 probands in each live decades). The superficial vascular plexus was scanned by videocapillaroscopy and assessed with the software Capilab Toolbox. The subpapillary vascular plexus was explored with laser Doppler flowmetry. The skin color a* was analyzed by chromametry. RESULTS: A marked site and age effect on the skin microcirculation has been demonstrated. The density of capillary loops in the eldest group decreased by about 40-70% compared with the youngest group whereas the vascular length increased by 35-156%. The capillary density in the back of the hand was 4 times higher than in the crow's feet. The vascular length in the crow's feet was 3 times longer than in the back of the hand. Both blood flow and skin redness (a*) increased also with age. CONCLUSION: Both morphology and quantification of the cutaneous microvasculature showed changes with site and age. Videocapillaroscopy associated to an image processing and laser Doppler flowmetry revealed different vascular layers. So the combination of both instruments offers an easy way to observe the architectural frameworks in vivo.

Age-related changes in skin topography and microcirculation.

Skin topography and microvasculature undergo characteristic changes with age. Although several non-invasive bioengineering methods are currently available to measure them quantitatively, few publications have referred to their relationship with age in different anatomical sites. This study was carried out to observe the age-related changes of the skin topography and skin microcirculation. The microrelief was assessed with special processing software from scanning by interference fringe profilometry of silicone replicas performed on two sites (volar forearm and back of hand) on 50 female volunteers (aged 20-74 years who consisted of ten probands in each decade). The superficial vascular network of both sites was assessed by videocapillaroscopy, and the subpapillary vascular plexus was studied with laser Doppler flowmetry. Skin color, which is affected by blood flow, was observed by colorimeter. The skin roughness and the mean height between peak and valley increased with age. There were statistically significant differences between the evaluated sites. This study also shows that the capillary loops in the dermal papillae decrease but the subpapillary plexus increase with age. The interference fringe profilometry associated with videocapillaroscopy may be useful and accurate to measure the efficacy of medical or cosmetic products to delay skin aging.

Evaluation of a sunscreen photoprotective effect by ascorbic acid assessment in human dermis using microdialysis and gas chromatography mass spectrometry.

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.

Capillaroscopy and videocapillaroscopy assessment of skin microcirculation: dermatologic and cosmetic approaches.

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: The 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.

Assessment of spray application of Saint GERVAIS water effects on skin wettability by contact angle measurement comparison with bidistilled water.

BACKGROUND: The skin is responsible for protecting the body from physical, chemical and microbial injuries. The stratum corneum is the top layer of the epidermis and it plays a key role in helping to contain moisture. When the skin becomes damaged, its ability to perform these functions is compromised. Dry skin is a common form of skin damage. Contact angle 0 between a surface and water is a good indicator of hydrophobic or hydrophilic tendency of surfaces. OBJECTIVE: To quantify the influence of spray application of an isotonic mineral water (Saint GERVAIS water) on the hydrophobic tendency of dry skin and to compare spreading of both types of water on the skin through 0 measurement of each water drop on the skin before and after mineral spray application. MATERIALS AND METHODS: Contact angles theta between skin surface and the two types of water (bidistilled and mineral water) were measured before and after application of mineral water by a system allowing the measurement of theta in vivo and in vitro. The cutaneous hydration, the temperature and pH were also measured before and after mineral water application. RESULTS: As for the application of mineral water, the cutaneous pH significantly increased so the strong skin acidity decreased. The cutaneous temperature was modified (a decrease of 2 degrees C was noted) and the cutaneous hydration was also increased (+47AU). The hydro-phobic tendency of the dry skin tested in this study was strongly decreased after mineral water application. This parameter was illustrated by a decrease of contact angle theta value. CONCLUSION: Saint GERVAIS water application allowed a regulation of skin pH, a fresh sensation on the skin and an increase in the cutaneous hydration. Moreover, the contact angle measurement with bidistilled water illustrated the increased wettability of the skin.

In vivo assessment of iron and ascorbic acid in psoriatic dermis.

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<0.05). Ascorbic acid in involved (47.3 +/- 8.2 microg/ml) and uninvolved (42.0 +/- 14.0 microg/ml) psoriatic dermis was statistically lower than that found in healthy dermis (176.8 +/- 29.0 microg/ml) (p<0.05). These results demonstrate that psoriatic patients exhibit high iron and low ascorbic acid concentrations in the dermis, but there were no significant differences between involved and uninvolved skin.

High iron and low ascorbic acid concentrations in the dermis of atopic dermatitis patients.

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 microg/l) compared to controls (21.8 +/- 1.2 microg/l) as well as a significantly lower concentration of AA (46.7 +/- 0.6 vs. 176.8 +/- 14.5 microg/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.