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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 281 (1989), S. 346-350 
    ISSN: 1432-069X
    Keywords: Sebum excretion ; Sebum resorption ; Skin surface lipids ; Stratum corneum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This paper describes an original in vivo device to investigate and quantify cutaneous resorption of sebum. Such a phenomenon was explored using a photometric determination of residual skin surface lipids at different times following initial deposits of known amounts of artificial sebum on demarcated areas. The technique was carried out on seven healthy subjects. The chosen area was the anterior aspect of the forearm, owing to the very low sebum production of this site, less than the sensitivity of the measuring instrument. The kinetics of absorption of applied sebum turned out to be hyperbolic-like and well correlated with experimental results (r=0.992), allowing a mathematical determination of the initial velocity of penetration of sebum into the skin, reaching 20 μg/cm2 · min for a standard program including a mean initial deposit of 116 μg/cm2. This kinetics actually does not fit with a true percutaneous absorption of lipids but is compatible with that of absorption into the stratum corneum. It conveys the faster absorption of the latter for sebum, a well-known but not so far quantified property of stratum corneum. The model here described is not at once transposable to skin areas with high sebum production since, quite obviously in such zones, the stratum corneum is permanently saturated with skin surface lipids. Therefore, the conclusions of this work cannot be correlated with the regreasing parameters studied so far on the forehead, but they provide interesting data about the evolution of sebum following its output onto the skin surface and therefore a better understanding of sebaceous physiology.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science, Ltd
    International journal of cosmetic science 23 (2001), S. 0 
    ISSN: 1468-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Until now, the wettability of the skin has been only estimated through the measurement of its critical surface tension (Zisman), or surface free energy. These methods give information on the behaviour of the surface with water, but cannot quantify its behaviour with other polar liquids.In this paper we propose to express both the hydrophilia of the skin (Hi) by the ratio of its critical surface tension (γc) to the water surface tension (γH2O), and its hydrophobia (Ho) by the ratio of the difference between the critical surface tension (γc), and the value of the water surface tension (γH2O) normalized by the latter. By using this proposed parameter, it should be possible to classify skin surfaces according to their affinities to water, which is of major importance in Cosmetology as well as in biology. We also discuss the relationship between surface hydrophilia (Hi) and polarity (P) as defined by Wu, and water adhesion tension (τo) as described by Vogler.The γc of untreated skin was 27.3 ± 3.6 mJ m−2, confirming previous data, and consequently basal Hi was 38%. Either cleaning with ether or hydration by occlusion induced a diminution of the wetting capacity of the surface and consequently a decrease of Hi to 29% and 33%, respectively. In contrast, washing the skin surface with soap and water increased surface Hi to 43%.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    International journal of cosmetic science 8 (1986), S. 0 
    ISSN: 1468-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The mechanical properties of stratum corneum and epidermis have been measured in vitro and a dispersity of approximately 30% to 50% between samples from the same donor has been found. To overcome such a limitation, a technique was developed in order to compare the mechanical properties of the same skin sample before and after treatment. The chosen parameter (initial slope of the stress-strain curve) appeared to be influenced by the topical application of products. A different time response was found with stratum corneum and epidermis reflecting their structural differences. Une nouvelle technique d'evaluation de l'effet des produits cosmétique sur les propriétés mécaniques du stratum corneum et de l'épiderme humains (etude in vitro)
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    International journal of cosmetic science 2 (1980), S. 0 
    ISSN: 1468-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: L'excrétion sébacée constitue une intéressante méthode indirecte de quantification de l'activité sécrétoire de ces glandes, malgré les fluctuations engendrées par des facteurs physiques environnants, tels que température cutanée et sudation. Les techniques d'exploration de l'excrétion sébacée se doivent d'être rigoureuses et au mieux codifiées, aussi bien dans la détermination de ses paramètres statiques (casual level ou CL) que dynamiques (sebum excretion rate ou SER). La méconnaissance encore à l'heure actuelle des mécanismes fins régissant l'excrétion sébacée, l'impossibilité d'affirmer ou d'infirmer une autorégulation, rendent compte des ecueils rencontrés dans l'exploration et la compréhension de ces phénomènes. Sebum Excretion. Methods of measurement and influence of physical factors 〈section xml:id="abs1-2"〉〈title type="main"〉SummarySebum excretion is the entire feature which governs sebum outflow to the skin surface through follicular pore. It can be measured by numerous methods, the first of which, devised by Emanuel in 1936, was a solvent extraction followed by desiccation and weighing. At present, virtually the only methods used are the gravimetric and photometric ones. The first one, using absorbent paper to collect the sebum, was introduced by Strauss and Pochi, and improved by Cunliffe and Shuster. Schaefer and Kuhn-Bussius’ photometric method is about as accurate as the previous one, but more simple and more rapid to use.Two parameters can be used to quantify sebum excretion: one static, the casual level (CL), i.e. the skin surface lipid amount of a non protected area neither wiped nor washed; the other is dynamic, the sebum excretion rate (SER), i.e. the skin surface lipid flow of a previously cleaned area. The significant differences of these values between different sex and/or age matched groups, give an account of the various stimulation levels of the sebaceous glands according to the underlying endocrine state.Several attempts have been made to show a sebum excretion regulation. Unfortunately, because of the divergences of their results, there is still no definite evidence of such an event occuring. Numerous experiments have also been carried out on the effects of skin temperature and sweat on sebum excretion.The first of these two parameters can act upon sebum skin surface spreading by changing sebum viscosity. The second one can modify local surface tension.Finally, the existence of a circadian rhythm constitutes a further parameter which must not be neglected when interpreting investigations of sebum excretion.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of cutaneous pathology 2 (1975), S. 0 
    ISSN: 1600-0560
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: In an attempt to determine the viral content and to observe the morphological features of clear cells in human warts of various clinical types, 17 lesions were studied with the electron microscope and 26 in thick sections. Plantar warts were, by far, the richest in viral particles, which are often found in crystalline arrangement. Morphologically, three groups observed in thick sections were also discovered with the electron microscope. In flat warts, poor in keratohyaline, the vacuolating process was total and massive, with abundant viral particles in the nucleus; two flat warts were taken from immunosuppressed patients and their appearance was quite similar to epidermodysplasia verruciformis lesions. In common warts, poorer in virus particles but rich in keratohyaline, vacuolization was often not complete. In plantar warts, characterized by their peculiar wealth in viral particles sometimes invading the cytoplasm, the production of keratohyaline was tremendous and the vacuolization, although often complete, was, however, not massive. Thus it seems that keratohyaline production is related to viral production but hampered by the vacuolating process and differing according to the ultrastructure of the three types of warts. It is suggested that the oncogenic potential of a wart (papilloma) may be related to decrease in keratohyaline production, i.e. cell maturation, and increase in vacuolization.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Journal of Chromatography B: Biomedical Sciences and Applications 563 (1991), S. 407-413 
    ISSN: 0378-4347
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 107 (1982), S. 0 
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 108 (1983), S. 0 
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The humoral and cell-mediated immune response to human papillomavirus type i (HPV-i) has been studied in 162 patients carrying papillomas of various clinical types: deep plantar wart or myrmecia, common wart, flat wart, and anogenital wart. Circulating antibodies were detected by immunodiffusion and microcomplement fixation, using purified HPV-i particles as type-specific antigen. A significant association between myrmecia and anti-HPV-i antibodies was found (39% of the cases).Cell-mediated immunity was evaluated by a study of delayed hypersensitivity (DH). The main capsid components of HPV-i (HPV-i CP), consisting mostly of a polypeptide of molecular weight 54,000, were injected intradermally. In addition to the type-specific antigens, HPV-i CP contain other antigenic determinants shared by various types of human papillomaviruses and masked in intact viral particles. The DH tests to HPV-i CP showed no differences between the carriers of different papilloma types, confirming the presence of common antigenic determinants. Moreover, they gave rise to an increase or to new anti-HPV-i antibody production mostly in myrmecia carriers (78% and 33% of the cases, respectively), and to new DH to HPV-i CP in all groups of papilloma carriers (33% to 56%, depending on the clinical papilloma type).
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 130 (1994), S. 0 
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Summary The aim of this study was to examine differences between the skin of both forearms with regard to several parameters: hydration (skin capacitance), transepidermal water loss (TEWL), pH and skin surface parameters. Possible correlations between measurements were investigated. Thirty-three healthy women (32.6 + 8.4 years) participated in the study. The different parameters were measured on each volar forearm (dominant and non-dominant) at precisely delineated sites. TEWL and developed length (DL) were significantly increased on the dominant forearm (P〈0·001 and P 〈0·01, respectively). In addition, a correlation matrix was calculated with the differences between dominant and non-dominant forearms for all the parameters measured. Only the skin surface parameters were found to be interrelated with this statistical approach. These data confirm that randomization between forearms is essential in the design of a reliable experimental plan, and indicate the lack of relationship between these measurements as assessed in a group of healthy young women.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 124 (1991), S. 0 
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: We report an unusual case of chronic actinic dermatitis associated with α1-antitrypsin deficiency and who responded well to treatment with danazol.
    Type of Medium: Electronic Resource
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