摘要:

SynopsisRheological analysis during the preparation of dermocosmetic products allows the deduction of properties related to consistency and fluidity, which are very important for cream application. This paper rheologically examines a cold‐cream formula, ‘Cérat Cosmétique’ from the French Pharmacopoeia. ‘Cérate’, or cold‐cream, is one of the most ancient cosmetic preparations.The Rheotest 2 viscometer, which was used for experimental determinations, allowed the rheograms to be plotted and the characteristic rheological constants to be calculated. On the basis of this information, the preparation under study was seen to present plastic behaviour. However, posterior thixotropic studies indicated that ‘Cérat Cosmétique, Ph. F.’ had no true t

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1990.tb00520.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SynopsisIn this study a compact, hand‐held, solid state erythema meter using light emitting diodes is described. This device has been constructed and used to compare with visual assessments of ultraviolet radiation in human subjects. A statistically significant correlation was obtained between erythema index and visual assessment in 24 ultraviolet irradiated subjects. Furthermore, the effects of three aftersun treatments have also been assessed objectively using the meter and subjectively using visual assessments. The ultraviolet‐irradiated areas were less red following treatment than the irradiated and untreated areas. The results obtained by the meter were similar to and statistically significant with those obtained by visual assessment.It is concluded that widespread use of an erythema meter such as that described would greatly improve all cutaneous erythema assessme

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1990.tb00521.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SynopsisReduction of keratin cystine by thioglycolic acid incorporated in microemulsions of the water/sodium dodecilsulphate/n‐pentanol/n‐dodecane system has been determined. The results obtained have been interpreted in relation to the properties of the reaction media. Microemulsions with constant oil‐to‐surface active mixture weight ratios (Ro/s) and different concentrations of water were chosen as reaction media. At low water concentrations a steep increase in reactivity with the increase of water was observed at all values ofRo/s. However it was more pronounced the higher the oil content. A relation between maximum cysteine formation and percolative behaviour of the microemulsion was found at highRo/

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1990.tb00522.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SynopsisTo minimise consumer risk of allergic contact dermatitis, predictive testing may need to be carried out. An alternative approach examining physicochemical properties of substances, and from these trying to assess sensitization potential, formed the basis of a model described by Roberts and Williams [1]. The concept related electrophilic reactivity (k), the partition coefficient (P) and dose (D) in a term which described a relative alkylation index (RAI). This was shown to correlate well with experimental data for sultones and p‐nitrobenzyl halides: RAI =kD/(P±P2) (1)In recent studies of dose response relationships, the ‘overload effect’ predicted by Roberts and Williams is demonstrable. However, the simple relationship above omits two potentially important parameters, ‘intrinsic antigenicity’ of a chemical and activation in skin of an apparently unreactive chemical. Data on the sensitization potential of alkyl transfer agents shows that for small haptens, intrinsic antigenicity may depend in part on the nature of modifications to carrier protein tertiary structure. The ability of skin to metabolise 1,4‐substituted benzene derivativesin vivoappears even more complex than suggested [2], involving a spectrum of reactive intermediates characteristic of each molecule.These results suggest that the RAI formula needs to

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1990.tb00523.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SynopsisPhotocontact allergy, an acquired altered reactivity of the skin to light in the presence of a photosensitizer, has for many years been considered to be a delayed‐type hypersensitivity. The response has been postulated as being mediated via the formation of a protein‐photoallergen conjugate acting as a complete antigen. The purpose of this paper is to bring together evidence at the molecular level which supports this theory of photoallergy.All photoallergens studied so far have been shown to be able to bind to proteins under the influence of ultraviolet light. Photoallergen‐protein binding in most cases is non‐specific; the exception, that of tetrachlorosalicylanilide (T4CS), displays a high specificity towards serum albumin.The mechanism of protein‐photoallergen binding is thought to proceed via the formation of highly reactive species such as free radicals. Free radicals have now been observed using electron spin resonance spectroscopy for at least five photoallergens.Macrophage inhibition and lymphocyte transformation experiments have indicated that protein‐photoallergen conjugates act as complete antigens. Further evidence for this is provided by the observation that photoconjugates injected into guinea‐pigs can induce a photoallergic response in the absence of irradiation. The response produced by T4CS‐serum albumin conjugates is greater than that produced by any other combination of photoallergen and protein. The potency of the T4CS‐serum albumin photoconjugate in inducing photoallergy, together with the binding specificity of T4CS, suggest that albumin may have a special role as a carrier protein in

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1990.tb00524.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

ISSN:0142-5463    

DOI:10.1111/j.1467-2494.1990.tb00519.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY