Joachim Ennen

Rapid in vivo measurement of the topography of human skin by active image triangulation using a digital micromirror device

Background/aims: Topometry is one of the most relevant methods for biophysical research on skin in dermatologic and cosmetic science, because it relates very closely to the perceived quality of skin. Taking silicon replicas of skin sites under investigation and measuring those imprints with mechanical or optical profilometers is still the most frequently used method. Direct measurement of the topography of human skin in vivo by active image triangulation avoids the need to make replicas and seems to be a promising alternative.

Regular use of a hand cream can attenuate skin dryness and roughness caused by frequent hand washing

BackgroundAim of the study was to determine the effect of the regular use of a hand cream after washing hands on skin hydration and skin roughness.MethodsTwenty-five subjects washed hands and forearms with a neutral soap four times per day, for 2 minutes each time, for a total of two weeks. One part of them used a hand cream after each hand wash, the others did not (cross over design after a wash out period of two weeks). Skin roughness and skin hydration were determined on the forearms on days 2, 7, 9 and 14. For skin roughness, twelve silicon imprint per subject and time point were taken from the stratum corneum and assessed with a 3D skin analyzer for depth of the skin relief. For skin hydration, five measurements per subject and time point were taken with a corneometer.ResultsWashing hands lead to a gradual increase of skin roughness from 100 (baseline) to a maximum of 108.5 after 9 days. Use of a hand cream after each hand wash entailed a decrease of skin roughness which the lowest means after 2 (94.5) and 14 days (94.8). Skin hydration was gradually decreased after washing hands from 79 (baseline) to 65.5 after 14 days. The hand wash, followed by use of a hand cream, still decreased skin hydration after 2 days (76.1). Over the next 12 days, however, skin hydration did not change significantly (75.6 after 14 days).ConclusionRepetitive and frequent hand washing increases skin dryness and roughness. Use of a hand cream immediately after each hand wash can confine both skin dryness and skin roughness. Regular use of skin care preparations should therefore help to prevent both dry and rough skin among healthcare workers in clinical practice.

Histometric data obtained by in vivo confocal laser scanning microscopy in patients with systemic sclerosis.

BackgroundIt would be a benefit if time-saving, non-invasive methods could give hints for diagnosing systemic sclerosis. To investigate the skin of patients with systemic sclerosis using confocal laser scanning microscopy in vivo and to develop histometric parameters to describe characteristic cutaneous changes of systemic sclerosis observed by this new technique, we conducted an exploratory study.Materials and MethodsFifteen patients with systemic sclerosis treated with extracorporal photopheresis were compared with 15 healthy volunteers and 10 patients with other disorders also treated with extracorporal photopheresis. All subjects were investigated using confocal laser scanning microscopy in vivo.ResultsMicromorphologic characteristics of skin of patients with systemic sclerosis and measuring parameters for melanisation, epidermal hypotrophy, and fibrosis for dislocation of capillaries by collagen deposits in the papillary dermis were evaluated. An interesting finding was an increased thickness of the tissue in the dermal papillae superior to the first dermal papilla vessel. It was also possible to reproduce characteristic histologic features by confocal laser scanning microscopy in vivo. Histometric parameters for fibrosis and vascular features developed in this study showed significant differences in patients with systemic sclerosis compared to controls.ConclusionsAlthough the predominant histopathological features in systemic sclerosis are findings of the reticular dermis and the subcutis, and in histopathological investigation the epidermis seems to remain unaffected by the disease, we have demonstrate some characteristic differences in the epidermis and papillary dermis by confocal laser scanning microscopy in vivo. Some of them have not been described so far. However, to use this technique as a tool for diagnosis and/or staging of systemic sclerosis, further studies are needed investigating the sensitivity and specificity of the histometric parameters developed in this study.

Standardized washing models: facts and requirements

REGULAR SKIN cleansing with washing substances has medical, cosmetic, hygienic and socio-cultural functions. In western cultures, the hygienic and cosmetic aspects prevail. The aim of a washing process is to remove or reduce dust particles, microorganisms and odorous substances. The resident skin flora in a washing process can be reduced significantly. The antiseptic effect of washing is gained independently from the function of tensides, through the removal of dust and dandruff material from the skin and hence through a reduction of growth medium for bacteria. A variety of surfactants are available, enabling the formulation of a broad variety of mild cleansing products. Modern surfactants in cleansing and hair care have been used successfully for about 30 years. However, the classical surfactants in soaps have been a fundamental issue in body care for at least 2000 years. The surfactants in modern cleansing products are anionics, nonionics and amphoters, each with a specific active profile. Besides the cosmetic performance, a potential irritation induced by surfactants and formulations has to be taken into account. Surfactants as single ingredients have become model irritants in dermatology and cosmetology when studying irritation profiles. Furthermore, sodium lauryl sulphate (SLS) has been used to study irritation pathways in basic research (1, 2). Finally, single surfactants have been tested to analyse the prerequisites for the optimal mildness of specific formulations in applied product development. The dermatological effects of surfactants on skin can be attributed to four fundamental mechanisms, finally affecting barrier homeostasis of the skin and other physiological factors: (i) adsorption to skin surface; (ii) removal of skin components; (iii) penetration into deeper skin layers and (iv) cytotoxic effects on living cells in the epidermis. Consequences of this interaction with skin especially with the stratum corneum (SC), are the well-studied symptoms of redness, scaling, swelling and dryness, which can be documented and quantified by clinical assessment and are nowadays measured by biophysical instrumentation (i.e. transepidermal water loss, roughness of skin surface, SC hydration, epidermal perfusion and skin colour). In addition, subjective perceptions of sensorial discomfort such as tension, burning or itching might occur alone or in combination with pathological skin symptoms.

Interlaboratory studies with a proposed patch test design to evaluate the irritation potential of surfactants

Background: Development of cosmetic products and household detergents necessitates comparative study designs to assess the skin tolerance of products. In initial tests, the epicutaneous patch test for irritation is widely used.