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Notes: Background/Aims: Mildness of skin cleansing products is often claimed although difficult to substantiate. Both the society and the producer share a common interest that cleansing products are safe in use and that valid methods are used for premarketing evaluation of new products. The object of the present study was to evaluate methodological aspects when three products were compared using two different test systems to characterize their irritant properties.Methods: A modified soap chamber test (M-SCT) and an iterative short-term patch test (IPT) were performed. Eight healthy female volunteers aged 18 to 55 selected as having responsive skin were studied. Colorimetry and measurement of transepider-mal water loss was employed. A soap, a synthetic detergent bar and a facial cleanser were studied with deionized water as a reference.Results: The IPT appeared more sensitive than the M-SCT for the detection and discrimination of irritation. The techniques allowed the ranking of the irritant properties of the products relative to water, which showed low values in both systems.Conclusion: Ranking of irritant properties of cleansing products was possible even in a limited number of individuals. Iterative short-term patch test was more sensitive than a modified soap chamber test.

Notes: Background D-Squames®, have gained wide acceptance for assessing skin desquamation. The amount of corneocytes adhering to D-Squames® can be assessed visually by trained observers or by computerized image analysis. Different image analysis algorythms for the evaluation of D-Squames® have been published but have not been compared with each other. It was our aim to develop an image analysis system that does not require an expensive image analysis programming tool but should be optimized for routine tasks of analysing large numbers of samples. A second objective of this study was to compare two published image analysis algorythms and visual grading.Material and Methods The hardware components of the system are a CCD camera connected to a frame grabber card and a light box equipped with fluorescent tubes on two sides that provide a relatively cool, diffuse and even illumination of the sample. The following features were included into the software: generation and identification of bar codes for sample identification; semiautomatic recognition of ROI (region of interest), integration of study design into the analysing process, rapid calculation of desquamation index (DI: integration of the per cent area covered by scales and their thickness distribution) and/or scaling index (SI: distribution of grey values), data storage and export for further analysis.In a first step the system was validated by examining D-Squames covering a wide range of desquamation, by examining different ROI shapes (circle and square), by performing repeat measurements with different positions of the samples and by repeat measurements after re-callibrating the system. In a second step the effect of treatment with different moisturizers was evaluated by the two image analysis parameters DI and SI and compared with hydration measurements (Corneometer®).Results The shape of the ROI showed no influence on the results (variability 〈 5%). Reproducibility of measurements was satisfactory (COV CDI): 1.7%, COV (SI): 2.6%).There was a good correlation between image analysis results and visual evaluation (means of 3 technicians) (r = 0.986) as well as between the two different image analysis parameters DI and SI (r = 0.971). In the clinical study moisturizer treatment resulted in variable reduction of desquamation that was closely correlated with increase in stratum corneum hydration (r = 0.97).Conclusion Analysing D-Squames® with the image analysis system proved to be reproducible, independent of the shape of ROI, cost effective and fast and easy to operate. It has shown to be a suitable and reliable method for the objective determination of desquamation levels.

Notes: Transepidermal water loss (TEWL) is an important parameter for the determination of skin barrier function. The open chamber method has been established as the technique of choice in most dermatological laboratories for measurements of TEWL. However, the influence of the probe temperature on TEWL measurements has been the subject of recent controversial debates. In this study the relationship between TEWL measured with the Tewameter and temperature of the measuring probe was therefore investigated by comparing two different measuring techniques.〈section xml:id="abs1-2"〉〈title type="main"〉Methods: For one measurement, the probe was kept at room temperature (20°C) and for the other one, the probe was preheated to the actual temperature of the measuring object before obtaining the values. Measurements were performed on evaporative standards (EvSs) and healthy individuals. For the EvSs, semipermeable membranes were pulled over a petri dish filled with water, which could be heated.〈section xml:id="abs1-3"〉〈title type="main"〉Results: TEWL values were found to depend on the temperature of the probe. TEWL values were higher when measured with the preheated probe. However, long-term measurements revealed that TEWL values measured with the unheated probe reached those higher TEWL values after approximately 8 min measuring time.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusions: The final TEWL value was reached after shorter intervals for the preheated probe compared to the unheated probe (2.5 min vs. 4 min) for some measurements. However, preheating of the probe resulted in greater variability of the measurement values. Therefore, measurements with a preheated Tewameter probe is not be recommended.

Notes: Ausgehend von einer operational vorgehenden Wissenschaftstheorie, die die kantische Ein-teilung der erfahrungswissenschaftlichen Urteile auf den heutigen Stand dieser philosophischen Disziplin überträgt, wird eine Epistemologie entwickelt, welche sich sowohl an den Ergebnissen der Metalogik und philosophischen Semantik als auch an den empirischen Hypothesen der gegen-wärtigen Wahrnehmungspsychologie orientiert. In bezug auf den Inhalt des zugrundegelegten Universums der zu interpretierenden Sprache wird hierbei eine Position des Suppositionismus vertreten, welche von einem sprachabhängigen Erkennen der Objekte ausgeht, deren Existenz somit nur vorausgesetzt werden kann. Bezüglich der Form des Universums wird eine extensionali-stische Haltung eingenommen, und die Frage nach der Rechtfertigung der Voraussetzungen empi-rischer Erkenntnis wird im Sinne eines Kondilionalismus entschieden, welcher insbesondere ein apriorisches Beweisen dieser Voraussetzungen ablehnt und somit auch epistemologische Umschichtungen beim Wechsel von Erfahrungserkenntnis berücksichtigt.

Notes: Ohne Zweifel stehen Sprachen und Konventionen in engen Beziehungen zueinander; grosse Teile der Oberflächenstrukturen unserer natürlichen Sprachen hängen von Konventionen ab, und um aussersprachliches Verhalten durch Konventionen zu regeln, benötigt man eine gemeinsame Sprache. Zu fragen ist dann, ob eine reale oder idealisierte Gemeinschaft von Personen sich eine gemeinsame Sprache durch irgendeine Art von Konvention erstmals schaffen kann, ohne dabei bereits ausdrücklich oder stillschweigend eine gemeinsame Sprache zu benützen, die nicht weniger ausdrücksreich als die zu kreierende ist. Es wird gezeigt, dass dies in unserer faktischen Welt nicht der Fall ist, und diese empirischen Gründe werden durch philosophische Argumente erhärtet, die sich auf Ergebnisse der Metalogik und der Wissenschaftstheorie beziehen, wonach eine Erstschaffung einer gemeinsamen Sprache ohne Voraussetzung einer mindestens genauso aus-drucksreichen Sprache der Teilnehmer – vom logischen Gesichtspunkt aus gesehen unmöglich ist, d. h. in keiner möglichen Welt vorkommt.〈section xml:id="abs1-2"〉〈title type="main"〉SummaryThere can be no doubt that languages and conventions are interrelated one to another; large parts of the surface structure of some given natural language depends on conventions, and some common language is necessary to create conventions with regard to non-lingual behaviour. Then the question arises, whether or not some real or idealized community may create a common language via some kind of convention without using explicitely or implicitely some common language being at least as rich as the language to be created. It is pointed out that this does not hold in our factual world, and those empirical reasons are supported by philosophical arguments referring to results of metalogic and philosophy of science indicating that radical creation of some common language without using some common language being at least as rich as the other is impossible from a logical point of view, i. e. will never occur in any possible world.〈section xml:id="abs1-3"〉〈title type="main"〉RésuméSans aucun doute, langues et conventions sont en relation étroite les unes avec les autres; pour une grande part, les structures superficielles de nos langues naturelles dépendent de conventions et, pour régler par conventions notre comportement non linguistique, il faut un langage commun. On peut ensuite se demander si une communauté réelle ou idéalisée peut se constituer, par quelque genre de convention, un langage commun sans pour cela utiliser, explicitement ou implicitement, un langage commun qui n'est pas moins riche en potentialités expressives que celui qu'il s'agit ?on;établir. On montre que cela ne se produit pas dans un monde factuel, et ces arguments empiriques sont confirmés par des arguments philosophiques se référant à des résultats de la métalogique et de la théorie de la science, selon lesquels la création originelle ?on;une langue commune est, du point de vue logique, impossible sans supposer chez les participants un langage au moins aussi riche (c'est-à-dire que cela ne se produit dans aucun monde possible).

Notes: Ausgehend von der philosophischen Grundhaltung Kants, dass jedes System von empiri-schen Urteilen – jede empirische Theorie – seine epistemologische Grundlage in einem System von synthetischen Sätzen, die hierfür apriorisch akzeptiert werden, hat, wird eine Axiomatisierung der Mechanik bis hin zum Impulsbegriff nach H. Hermes dargestellt. Dieses System von Axiomen veyendet als Grundbegriffe lediglich den der reellen Zahlen, den des Bezugssystem, der den Übergang zum mathematischen Raum ermöglicht, und den der Genidentität, der das stetige Fortschreiten von Materiepunkten beschreibt.Das System von Hermes wird als eine mogliche Métaphysik der Mechanik gesehen; somit wird der Fundamentalismus Kants bezüglich der Einzigkeit eines solchen Systems abgelehnt.

Notes: Since irritants are the major cause of contact dermatitis, it is important to identify those chemicals that possess significant ability to cause skin irritation. This process must then be followed by risk assessment and risk management. Historically, animal tests have played a major rôle in this process, but human volunteer studies are of increasing importance in the field. Where the appropriate safely and ethical controls are in place, human testing can give data that identities skin irritation hazard. To be of widest value, these human studies must not he flawed due to inter-individual, inter-ethnic or seasonal variation. We conducted a large dose-response study and studied the impact of summer and winter weather on a predictive human assay. Sodium dodecyl sulphate (SDS) was tested at 0.1%-20% in 3 national groups of approximately 100 volunteers, using 25 mm Hill Top chambers loaded with 0.2 ml solution and applied to the tipper outer arm for 4 h. Reactions were scored at 24. 48 and/or 72 h after patch application. The German and Chinese studies were completed in a few weeks under. similar winter conditions, whereas the UK work was spread fairly evenly over about a 15-month period Some relatively minor differences were observed in the dose-response curves obtained, probably due to weather conditions. The effect of me weather on the intensity, but not the put tern, of irritant reactivity was also evident in the smaller specific study that assessed reactions to SDS in summer and in winter. Whereas 45% of the panel reacted to 20% SDS in summer, 9l% reacted in the winter. However, in both studies, substantial inter-individual variations in response to SDS dominated the pattern of response. When designing a human patch test to discriminate skin irritant substances from those that are of minimal effect, it is this inter-individual variability, rather than any small inter-ethnic or seasonal variation, which must be taken into account. This can be achieved by the routine inclusion of a suitable positive irritant control, which then calibrates each human volunteer panel.

Notes: Non-immune immediate contact reactions (NIICR) arising from skin contact with a wide range of chemicals have been well described. There is evidence that many, if not all, individuals are susceptible to this effect: it may be just a matter of applying a higher dose to the most resistant types of skin. In this work, we chose to evaluate susceptibility to development of NIRCR in a large unselected population. Skin tests were made with 1 known unlearns (benzoic acid, trans-cinnamic acid and methyl nicotinate). each al 2 concentrations. In a group of 200 volunteers, it was demonstrated that all 3 chemicals induced NIICR in the majority of people. Approximately 10%. of the volunteers appeared particularly sensitive, reacting fairly strongly to 2/3 urticants. In contrast, another subset, also about 10% failed to respond significantly to any of the chemicals at any dose. However, strong reactivity to one urticant was not predictive of the reaction to the other urticants. In a number of cases, individuals reacting strongly to one urticani reacted very little it' at all to the other unlearns. Also, the type of response, erythema or oedema, was specific to an individual. There was no significant correlation with age or sex on the degree of NIKR. In conclusion, it has been demonstrated that there is a wide interindividual variation in the response to chemical urticants. which cannot be predicted on the basis of age or sex. The prospect of identifying y panel of individuals generally sensitive to non-immune immediate contact reactions seems limited

Notes: This report reviews individual-related variables (age, sex, race, anatomical site. skin surface properties), intra- and interindividual variation (temporal, physical and mental activity, orthostatic effect, menstrual cycle/menopause), environment-related variables (light conditions, temperature) and various instrument-related variables that influence skin colour. CIE colorimetry (Minolta Chroma Meter) and spectrophotometric measurement (Derma Spectrometer) are considered. The guidelines give recommendations for measuring conditions and procedures.

Notes: This report reviews how to set up a laser Doppler perfusion imaging system intended for visualization of skin blood perfusion, capture images and evaluate the results obtained. A brief summary of related papers published in the literature within the areas of skin irritant and allergy patch testing, microdialysis and skin tumour circulation is presented, as well as early applications within other fields such as diabetology, wound healing and microvascular research.