Unexpected distribution of surface hydration level of the lip.

BACKGROUND: The functional properties of human lips depend on their hydration level. Limited data are, however, available. OBJECTIVE: To investigate water distribution through the lower lip surface. METHODS: Images from the surface of the lip were recorded using a new capacitance imaging technique. Capacitance and conductance measurements were also carried out in various points of lower lip and on adjacent skin. RESULTS: Data clearly show that the closest part of the mucosa of the lip is less hydrated than the external part. These unexpected findings could be related to the presence of a premucosa area whose structure is clearly different from that of vermilion zone.

Ptosis of submental skin: objective measurements and effect of age.

BACKGROUND/PURPOSE: Sagging of the face skin is a visible and unattractive characteristic of skin ageing. This phenomenon, due to both gravitational force and age-related alterations in the mechanical properties of skin, has never been quantitatively studied. The aim of this paper was, first, to define a method and a precise procedure allowing the objective measurement of this phenomenon and, second,to study how it is related to age. METHODS: We used an electronically controlled bed that allows the comparison of submental skin profiles in both the reclined and the upright positions. A parameter that characterises the sagging amplitude for an individual was defined and the reproducibility of measurement of this parameter was verified. RESULTS: Results, obtained from 66 female volunteers, demonstrated a statistically significant positive correlation between this new parameter and age, and also between this new parameter and the elastic recovery parameter of skin, as measured by torquemeter. CONCLUSION: Age-related changes of the skin's mechanical properties and of the various underlying skin tissues would explain this phenomenon. This new method and procedure should allow objective evaluation of the efficacy of any treatments (cosmetic, medical or surgical) proposed for rendering the appearance of people younger.

Influence of age on the lips and perioral skin.

BACKGROUND: There are few objective descriptions of the age-related changes taking place on the lips and perioral skin. This zone, however, has great importance in relational functions. OBJECTIVES: To describe quantitatively the age-related changes in dimension of the lips and the appearance of the perioral wrinkles, to revisit, thanks to a new method, the pattern of the lip furrows, to compare the hydration states of the upper and lower lips. METHODS: On 100 women, we clinically scored wrinkles, dryness of the lips and the general photoageing of the facial skin. We used a Corneometer for measuring dryness of the lips and SkinChip for recording lip surface patterns. RESULTS: The upper lip is more hydrated than the lower one, and there is no correlation between lip capacitance and the clinical score of lip dryness. The surface pattern can be classified into 3 main groups with no relation to age. Wrinkle number and visibility are linearly related to age, becoming visible during the fifth decade. The intercommissural distance increases with age, whereas lip height decreases. CONCLUSIONS: Both lips are different in terms of dryness. Inversely to their surface pattern, their dimensions are markedly changed with age. The time of apparition of vertical wrinkles suggests a possible influence of hormones.

Do cosmetics enhance female Caucasian facial attractiveness?

This study sought to investigate whether cosmetics do improve female facial attractiveness, and to determine whether the contribution of different cosmetic products are separable, or whether they function synergistically to enhance female beauty. Ten volunteers were made up by a beautician under five cosmetics conditions: (i) no make-up; (ii) foundation only; (iii) eye make-up only; (iv) lip make-up only; and (v) full facial make-up. Male and female participants were asked to view the 10 sets of five photographs, and rank each set from most attractive to least attractive. As predicted, faces with full make-up were judged more attractive than the same faces with no make-up. Sex differences within the results were also apparent. Women judged eye make-up as contributing most to the attractiveness. Men rated eye make-up and foundation as having a significant impact on the attractiveness of a full facial makeover. Surprisingly, lipstick did not appear to contribute to attractiveness independently.

Quantitative assessment of skin aging.

Noninvasive methods have allowed physicians to give an objective description of aged skin in terms of functional and esthetic properties. The relative influence of environment (mainly sun) on the true aging process can be assessed through the obtained data. It is also possible to measure the efficacy of topical preparations (cosmetics or drugs) designed for treating the various cutaneous aging marks.

[Chemistry of cosmetics in antiquity]. / Chimie et maquillage dans l'Antiquité.

Several texts, statues and paintings denote the importance of make up and eye medicines since the earliest periods of Egyptian history. We have investigated cosmetic powders that were preserved in original alabaster and reed containers. Quantitative crystallographic and chemical analysis of the mineral and organic components revealed surprising facts. In addition to the well known galena PbS and cerussite PbCO3, two unexpected constituents have been identified: laurionite PbOHCl and phosgenite Pb2 (CO3) Cl2, which are rare halide minerals found in lead slag only in certain places where the sea water has weathered lead debris left over from silver mining operations in Antiquity. Alteration of natural lead minerals is also unlikely, given the excellent state of conservation of the reed vessels. This evidence indicates that laurionite and phosgenite were synthesised artificially. Support for this statement comes from recipes of medicinal products to be "used in ophthalmology" reported by Greco-Roman authors such as Dioscorides and Pline (1st Century B.C.): silver foam PbO is crushed and mixed with rock salt and sometimes with natron (Na2CO3). The reaction seems to be straightforward. However, our experiments in the laboratory have shown a major difficulty, arising from the concomitant production of alkali, which raises the pH and leads to different products. It follows that the Egyptians very early mastered this kind of chemical synthesis and technology, a fact of great importance in the History of Sciences. Fire-based technology had been mastered to manufacture Egyptian Blue pigments since the third millennium B.C. The present results now suggest that wet chemistry was already known 4000 years ago. This key finding provides a new insight into the chemical technology of far greater antiquity than has previously been believed. Yet, an important question remains relative to the ultimate motivation for these technological developments. If the Egyptians initially only aimed at different nuances of grey, they could use cerussite, an easily accessible mineral, crushed and mixed with galena. Thus, one should seek other motivations; we shall propose to consider a religious-ritual context, ultimately linked to a pharmaceutical aspect.

Influence of hairdressing on the psychological mood of women.

A questionnaire, specially designed to measure the mood change was filled in by 359 women at their arrival in different hair-salons and after having received various hair care services. The results show that hair treatments increase all the positive dimensions of mood and decrease all the negative ones. Only the improvement in sociability appears to be linked to age.

Profiling lipids across Caucasian and Afro-American hair transverse cuts, using synchrotron infrared microspectrometry.

Synchrotron-based infrared microscopic measurements have been performed on various hair transverse sections, sampled either from the heads of Caucasian or Afro-American subjects. Lipid content of various virgin hair transverse sections was established, with an unprecedented resolution. The variations in shape and intensity of the CH(2), CH(3), amide I and amide II bands, before and after lipid removal by solvent extraction, were profiled, showing clearly that Caucasian hair often contains lipids localized inside the medulla and to a lesser extent inside the cuticle. This statement does not hold for the Afro-American hair analysed. For this, the FT-IR spectra do not change within the hair section and are insensitive to solvent extraction. The importance of the origin of hair on its physical and chemical properties has to be taken into account in future investigations.

Changes in tactile spatial discrimination and cutaneous coding properties by skin hydration in the elderly.

Neurosensory tactile functions were investigated in human subjects by two different and complementary experimental approaches. First, a conventional psychophysical method (two-point gap discrimination) was used to determine the tactile discrimination threshold by analyzing the subjects' ability to detect a gap of variable width between two contact points when a series of stimuli was applied to the skin. Using this method we confirmed the marked degradation of tactile spatial acuity with age and showed that skin discriminative function was partially restored after hydration of the skin with a moisturizer. The second approach consisted of a microneurographic recording of tactile afferent fibers in response to two types of mechanical stimuli applied reproducibly to the corresponding receptive fields. With this method, we found that the afferent messages were depressed following hydration of the skin surface. Thus, partial restoration of tactile spatial acuity after hydration appears to be due to both a softening of the stratum corneum permitting better localization of the stimulus and a weaker transfer of the stimulus toward the sensory receptors.

Frictional properties of skin: proposal of a new approach.

Phenomena occurring at the interface between skin and a glass pad, alternatively moved at its surface, are described by direct observation and measured by recording the force on the pad induced by the skin displacement. Static and dynamic friction coefficients are determined as a function of the load applied on the pad. Influence on the recordings of the friction coefficient of some cosmetic treatments applied on the skin are described. Results show that discontinuous phenomena, due to compression and distortion of the skin microrelief, occur during the beginning of the sliding process. Friction coefficients are depending on the load applied on the pad. Our studies confirm the increase of friction coefficient after hydration of the skin surface and suggest that the fluctuations in the frictional force amplitude could supply an objective, although indirect, measurement of skin smoothness.

Comparative effects of retinoic acid, glycolic acid and a lipophilic derivative of salicylic acid on photodamaged epidermis.

BACKGROUND: Studies comparing purported antiaging compounds are rare. OBJECTIVE: To compare in a randomized, placebo-controlled double-blind study 10% glycolic acid (GA), 2% 2-hydroxy-5-octanoyl benzoic acid (beta-lipohydroxy acid, LSA) and 0.05% all-trans-retinoic acid (RA). METHODS: Women volunteers treated one forearm twice daily with one of the active products and the other one with the vehicle. Comparative evaluations of efficacy were made using histochemistry and quantitative immunohistochemistry. RESULTS: Improvement in the various epidermal compartments was the most prominent finding at the RA-treated site. The LSA-treated site also exhibited similar positive changes, although to a lesser degree. GA showed no significant effect. CONCLUSION: In the presently tested concentrations and formulations, RA had a beneficial impact upon the aging epidermis. LSA mimicked RA but with somewhat lesser efficacy. By contrast, GA appeared almost inactive.

EEMCO guidance for the assessment of skin topography. The European Expert Group on Efficacy Measurement of Cosmetics and other Topical Products.

Numerous factors can modify the visibility or the actual dimensions of the skin microrelief and wrinkles. To quantify these changes, several methods, including clinical and non-invasive ones, have been proposed. This article reviews the advantages et drawbacks of all of them and lists some experimental recommendations to make the results of studies using these methods, more reliable.

Mexoryl SX: a broad absorption UVA filter protects human skin from the effects of repeated suberythemal doses of UVA.

There is now considerable evidence that chronic UVA exposure induces damage in animal and human skin; however, little is known about UVA protection of human skin. The aim of this study is to evaluate the efficacy of Mexoryl SX, a broad UVA absorber (lamada max = 345 nm) against UVA-induced changes in human skin. The regimen of UVA exposure (13 weeks with increasing suberythemal doses) induces intense pigmentation with no erythema. Skin hydration and elasticity decrease, whereas total skin thickness, assessed by echography, remains unchanged. Irradiated epidermis reveals a significant thickening of the stratum corneum, an absence of hyperplasia and an increase in the expression of the protective iron-storage protein ferritin. No significant alterations are seen using antisera against type IV collagen or laminin, suggesting that the dermal-epidermal junction (DEJ) is mainly preserved. In dermis, enhanced expression of tenascin is seen just below the DEJ but type I procollagen, which is localized at the same site, is unaltered. Although we are unable to visualize any changes in elastic network organization using Luna staining or specific antiserum directed against human elastin, we notice an increased deposition of lysozyme or alpha-1 antitrypsin on elastin fibres. Mexoryl SX (5%) efficiently prevents these alterations. Thus, these results suggest that UVA photoprotection can prevent early putative alterations leading to photoageing.

Dermo-epidermal stimulation elicited by a beta-lipohydroxyacid: a comparison with salicylic acid and all-trans-retinoic acid.

Although ageing has been thought to be irreversible, studies made during the last decade have shown that a few topical compounds may limit or improve the age-related skin damages. The efficacy of tretinoin (all-trans-retinoic acid) in treating photoageing is well established. Identifying other compounds with similar effect and improved tolerance would be greatly valued. In this double-blind study, a new beta-lipohydroxyacid compound was evaluated. To address a comparison between products, 6 volunteers completed a 4-week study using twice daily 0.025% tretinoin, 5% salicylic acid, 1.5% beta-lipohydroxyacid or vehicle. Immunohistochemistry and computerized image analysis were performed on skin sections from biopsies taken after treatment. We searched for changes in epidermal renewal (Ki-67 labeling), modifications in cytokeratin (56-65 kD) and filaggrin patterns, and in tumor necrosis factor alpha (TNF-alpha), Ulex europaeus and factor XIIIa expressively. The vehicle- and salicylic-acid-treated areas had an aspect similar to untreated control sites. Both beta-lipohydroxyacid and tretinoin induced enhanced epidermal proliferation and thickness with activation of factor XIIIa+dendrocytes. The effects were more pronounced at the tretinoin-treated site. We speculate that TNF-alpha might mediate some of the dermal effects. The beta-lipohydroxyacid mimics some of the stimulatory effects of tretinoin on the epidermis and dermis. This new compound should be listed among topical products boosting the skin tissues affected by ageing.

In vivo confocal microscopy of human skin: a new design for cosmetology and dermatology.

In-depth exploration of cellular structures in living human skin in situ is possible with the tandem scanning microscope (TSM). However, the rigid design of the microscope limited observations to the arms, hands, and fingers. A mobile version allowing the investigation of any parts of the body has been designed. The head containing the Nipkow disk and the optical path were the only part saved from the original TSM. This prototype can be used to observe, in real time, the different skin structures down to a depth of 200 microns and to measure the thickness of the different layers with micron precision level. The hydration of the stratum corneum (SC) could be assessed. For example, lengthy immersion of the hand in water led to an increase in SC thickness without affecting that of the living epidermis. Occlusive patch tests also showed that water and, even more so. propylene glycol, led to transient swelling of the SC. In dermatology, the example of psoriasis illustrated the value of the TSM for describing, measuring, and assessing pathologic skin changes. The availability of this noninvasive method for observing changes with time in a given skin site should prove useful for monitoring treatment efficacy. This tool opens up new insight for the investigation of cutaneous pathophysiology.