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Notes: Background  The pathogenesis and aetiology of atopic dermatitis (AD) remain unclear. Establishment of suitable animal models should aid elucidation of the pathogenesis and development of therapy. Objectives  We focused on biophysical and biochemical parameters in the skin of NC/Nga Tnd mice to evaluate similarities to and differences from AD. Methods  Biophysical (transepidermal water loss and skin surface conductance) and biochemical parameters (ceramide contents and activity of ceramide-metabolizing enzymes) were measured in NC/Nga Tnd mice in which spontaneous dermatitis appeared under ambient laboratory conditions (ALC). Results  Biophysical parameters suggested impairment of water retention properties and barrier function. The amount of ceramide in NC/Nga Tnd mice under ALC decreased significantly. These dermatological features resembled those of AD, as did the clinical signs and histological changes. Conclusions  The results described here and previous immunological studies on AD suggest that the NC/Nga Tnd mouse may be a suitable model for certain aspects of AD.

Notes: Transepidermal water loss (TEWL), skin surface water loss (SSWL) and water content of the stratum corneum are utilized to assess the hydration effects of moisturizers and soaps. The relationship among these parameters may help differentiating hydration obtained via occlusion or by water-holding in the stratum corneum. Furthermore, skin function (hydration, dehydration, barrier damage) can be studied comparing the data obtained with these techniques. In this study, the effects of glycerol, petrolatum, soaps and commercial moisturizers on the skin are investigated and discussed.

Notes: Stratum corneum moisturization was measured by two instruments simultaneously on the same subjects at different body sites. One instrument is based on the 1 GHz focused mirowave dielectric measurement; the other instrument measures impedance at 16 Hz.A linear relationship r = 0.86 was observed between the measurements by the two above-mentioned instruments. The 1 GHz focused microwave measurement is more accurate in measuring water concentration in the stratum corneum, especially in the upper layers relevant to “moisturization”; it is, however, an expensive research instrument. The low frequency impedance measurement involves a much simpler, cheaper and portable instrument which can be used routinely to evaluate ‘moisturization’ for the purpose of skin classification under field conditions.Comparaison de divers appareils de mesure de I'hydratation de la couche cornee〈section xml:id="abs1-2"〉〈title type="main"〉ésuméL'hydratation de la couche cornée a été mesurée simultanément par deux appareils sur plusieurs sites de mêmes sujets: le front, la face et les membres. Un appareil est basé sur la mesure par micro ondes, I'autre mesure I'impédance à 16 Hz.On observe une relation linéaire, r= 0.86, entre les mesures effectuées par les deux appareils ci-dessus. L'appareil à micro ondes est plus précis pour la mesure de la concentration en eau de la couche cornée et plus spécialement dans les couches supérieures qui sont importantes pour I'hydratation, mais cet appareil est onéreux. La mesure des impédances à basse fréquence utilisé un appareil portable, simple et bon marché qui peut être utilisé en routine pour évaluer I'hydratation dans le but de classer des types de peaux sur le terrain.II n'est pas toujours possible de comparer des appareils diffeérents sur les mêmes personnes et dans le même temps et il est encore plus difficile d'obtenir des donneées sur un nombre de personnes de type diffeérent. Nous suggeérons d'utiliser à I'avenir une meéthode de comparaison diffeérente basée sur I'application d'un traitement standard bien défini, qui pourrait par example consister en I'application pendant une heure d'une solution à 2% de glycérine sur I'avant bras, avant la mesure.Ces données, avec la connaissance de la distribution des valeur du prétraitement pour les divers appareils, permettraient également la comparaison et la validation des différentes méthodes.

Notes: Irritant contact dermatitis (ICD) is a common dermatological diagnosis in which endogenous and exogenous factors have been implicated. This review explores ethnicity as a possible endogenous factor. While there is a clinical consensus that blacks are less reactive and Asians are more reactive than Caucasians, the data supporting this hypothesis rarely reaches statistical significance. The studies reviewed do not provide sufficient evidence to determine that race is a predisposing factor to the degree of irritation in ICD. We conclude that race could be a factor in ICD, which has practical consequences regarding topical product testing requirements, an ever-expanding global market, occupational risk assessment, and the clinical thinking about ICD. Pitfalls in defining differences are discussed.

Notes: Spectrophotometric analysis for chromium in hypochlorite bleach sampled at random throughout the USA shows that the highest level found in those products is of the order of O.1 ppm (2/20). This probably does not represent a significant risk factor for chromate sensitization of the consumer population.

Notes: To examine possible ethnic variations in perception of sensitive skin, an epidemiological survey was performed in the San Francisco area. Approximately 800 telephone interviews were conducted with women from four different ethnic groups (Afro-Americans, Asians, Euro-Americans, Hispanics; approximately 200 women per group). In addition to sensitive facial skin assessments, age and other general skin condition data were collected. 52% of the subjects identified themselves as having sensitive facial skin. There was no statistical difference between the ethnic groups in terms of sensitive skin prevalence. Nevertheless, some differences were noted between ethnic subgroups of sensitive skin. Euro-Americans were characterized by a higher skin reactivity to wind and tended to be less reactive to cosmetics. Afro-Americans presented diminished skin reactivity to most environmental factors and a lower frequency of recurring facial redness. Asians appeared to have greater skin reactivity to spicy food, to sudden changes in temperature and to wind, and tended to suffer from itching more frequently. Hispanics presented a lower incidence of skin reactivity to alcohol. The differences in skin sensitivity between ethnic groups concerned mostly factors of skin reactivity and, to a lesser extent, its symptomatology. But, taken together, we note the similarities in comparing how women of varying ethnic backgrounds perceive the sensitive skin condition.

Notes: The incidences of sensitisation to Kathon® CG are reported for patients routinely tested from 1984 to 1986 in Bari. London. Louvain, Nijmegen, Oulu and San Francisco, For these 3 years, the overall frequency of sensitisation varied for women from 3.3% in Oulu to 0.6% in London and San Francisco and for men from 1.4% in Oulu to 0% in San Francisco. Women were predominantly sensitised, probably by cosmetics, toiletries and domestic cleaners. Occupational sensitisation was much less frequent.

Notes: Reactivity to repeated daily sodium lauryl sulfate (SLS) applications and patch test reactivity to SLS was studied in 23 females. Skin changes were quantified by transepidermal water loss (TEWL), dielectric water content (DEWC), laser Doppler velocimetry (LDV) and visual scaring DS). Dermatologic histories (HS) and susceptibility to sunburn (ST) were obtained and clinical skin dryness evaluated (DS). Great interindividual variation occurred in the degrees of changes in (he biophysical parameters measured; the variation was most apparent in TEWL. The subjects with HS I or more developed greatest TEWL increase after open SLS applications (p 〈 0.05). DS showed poor correlation with SLS reactivity and only minor DEWC alterations were seen. ST showed some non-significant correlation with erythema reactivity in the patch test.

Notes: Reactivity of white and hispanic skin after exposure to sodium tauryl sulphate (SLS) has been investigated. The tests were performed on the back as follows: untreated skin, skin pre-treated with short-term occlusion and delipidized skin. Irritant reactions were induced by applying 0.5% and 2.0% SLS via Finn chamber patch tests and monitored by means of laser Doppler velocimetry (LDV), transepidermal water loss (TEWL) and stratum corneum water content (WC). Higher TEWL, LDV and WC were recorded for 2.0% SLS when compared to 0.5% SLS and baselines. Differences between while and hispanic skin reactivity were recorded. TEWL and WC responses showed a greater sensitivity in hispanics possibly reflecting a different modulation of the water burner function after chemical exposure. On the other hand, the microcirculatory response, as long as detected with LDV, was similar in the 2 groups. Correlations between these data and findings observed in other races are discussed.