bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution analytique à la détermination de la pureté et du degré de polymérisation de l'Acide Hyaluronique
Authors: DAVID M. , BLANDEL H.
Published: May 2007

De par ses propriétés physico‐chimiques et son rǒle biologique tissulaire, l'Acide Hyaluronique s'avère une molécule de choix pour la formulation cosmétique. Les divers échantillons commerciaux présentent des teneurs variables en chondroitines sulfates, composants biologiques naturellement associés.

D'un point de vue analytique, les auteurs ont étudié la possibilité de séparer l'Acide Hyaluronique des chondroitines sulfates par une méthode simple et rapide, laquelle ne nécessite qu'une infime quantité de produit à tester.

Pour ce faire, ils utilisent la chromatographie par perméation de gel ou chromatographie de type exclusion. Les chromatogrammes obtenus par cette technique permettent de visualiser l'Acide Hyaluronique et les chondroitines sulfates sous forme de deux pics juxtaposés dont les surfaces sont proportionnelles aux teneurs respectives des deux polysaccharides.

Le profil configurationnel du pic correspondant à l'Acide Hyaluronique et son volume de rétention apportent de précieux renseignements sur le caractère polymérisé de l'échantillon.

Comparéà un étalon connu, il est possible en 30 minutes de déterminer les pourcentages respectifs en Acid Hyaluronique et chondroitines sulfates d'un échantillon et de préciser le degré de polymérisation de celui‐ci.

Analytical contribution to the determination of the purity and the degree of polymerization of Hyaluronic Acid

Hyaluronic Acid (H.A.) is of importance in cosmetic formulation because of its physical chemical properties and its role in biological tissues; it occurs in association with chondroitin sulphates and a method of analysis of separating the two substances has been developed.

The method is based on gel permeation chromatography, or ‘exclusion’chromatography, and requires extremely small quantities of product. The conditions which have been found give two neighbouring peaks of which the surfaces are proportional to the contents of H.A. and the chondroitin sulphates.

In addition to the quantity, the shape of the H.A. peak and the relative retention volume give further information as to the polymerization character of the sample. Using a known control sample it is possible, in 30 minutes, to determine the relative proportions of the polysaccharides H.A. and chondroitin sulphates and to determine the degree of polymerization of the H.A.

Results are given of the analysis of a commercial sample of H.A.
Influence du butyrylhydroxyproline sur le developpement des fibroblastes en culture
Authors: MARTINI M. C. , DOLQUES Ch. , VIOLLAND N. , COTTE J.
Published: May 2007

Les auteurs ont cherchéà mettre en évidence éventuelle action d'un lipoaminoacide, le butyrylhydroxyproline, à la fois sur la vitesse de croissance des fibroblastes en culture et sur leur capacité de biosynthèse des protéines.

Les cultures cellulaires ont été réalisées en milieu de HAM additionné de 10%, 5% ou 2% de sérum de veau nouveau‐né et l'évaluation de la croissance cellulaire effectuée par comptage. Les souches utilisées provenaient de prélèvements de peau humaine (fetus, enfant, adulte) mis en culture monocouche et utilisés à des stades de subculture voisins.

La biosynthèse des protéines a étéétudiée par incorporation de L‐Proline 3H‐5 ou de L‐Leucine 3H à raison de 5 μCi/ml de milieu de culture, soit 3 jours, soit 7 jours après confluence.

Les produits étudiés furent:

— le butyrylhydroxyproline en solution à 48%;

— le N‐acetylhydroxyproline servant de produit de référence.

Après détermination de la cytotoxicité, les quantités incorporées furent les suivantes:

— de 10 à 100 μg de produit pur par millilitre de milieu de culture pour le lipoaminoacid butyrylhydroxyproline;

— de 17.4 à 500 μg/ml pour le N‐acetylhydroxyproline.

Quelles que soient les conditions expérimentales et les concentrations utilisées, les deux produits sont sans action nettement significative sur la croissance cellulaire. En revanche, les auteurs ont pu mettre en evidence une action sur la biosynthèse des protéines totales pour les deux produits. Trois à cinq jours après la confluence, le lipoaminoacide et le N‐acetyl hydroxyproline provoquent une augmentation d'environ 30% de la biosynthèse des proteines par rapport au témoin. Cette action se manifeste pour des doses faibles (10 à 20 μg/ml) et pourrait correspondre à une augmentation du métabolisme cellulaire.

Influence of butyrylhydroxyproline on the development of fibroblasts in culture
Effect of placental extracts on the growth of fibroblasts in vitro
Authors: L'HEVEDER Ch. , MARTINI M. C. , COTTE J.
Published: May 2007

Synopsis

Monolayer cultures of human fibroblasts were used both to confirm clinical experiments in which it was found that placental extracts increased the rate of healing and to demonstrate the action on cellular regeneration. The cytotoxic dose of lyophilized extracts from human placentae was first determined and the extracts were then added to culture media at concentrations of 100 to 400 μg/ml.

A variable amount of newborn calf serum was used in order to obtain media lacking nutrient substances. The tests were carried out on cells from both young and elderly donors and growth was evaluated by counting cell numbers and by microassay of DNA.

A stimulatory action of the placental extracts was only observed on young cells cultivated in deficient culture media and no stimulation could be demonstrated on cells aged in vivo or in vitro.

Effets des extraits placentaires sur la croissance des fibroblastes in vitro
A comparison of the in vitro permeability properties of human and some laboratory animal skins
Authors: SCOTT R. C. , WALKER M. , DUGARD P. H.
Published: May 2007

Synopsis

The in vitro permeability of human and some common laboratory animals'skin has been measured to two chemicals with different physico‐chemical properties: [3H] water, a small polar molecule and [14C]paraquat dichloride (the ion), a fully ionised divalent cation. All the skins examined had similar permeabilities to [3H]water: relative to human skin the greatest difference (x4.8) was measured through guinea pig skin. However, relative to human skin, all the animals were much more permeable to [14C]paraquat, with factors of difference ranging between 40 (haired rat) and 1460 (hairless mouse). The in vitro technique allows the permeability of human and animal skin to be compared, facilitating extrapolation to Man of effects seen in animals during dermal exposure studies.

Comparaison de la permeabilite in vitro de la peau humaine et de la peau de certains animaux de laboratoire
Identification et dosage de l'hydroquinone et de ses éthers méthylique et benzylique dans les produits cosmétiques pour blanchir la peau
Authors: HERPOL‐BORREMANS M. , MASSE M. O.
Published: May 2007

Mise en évidence de l'hydroquinone et de ses éthers méthylique et benzylique par chromatographie sur couche mince d'adsorption.

Détermination qualitative et quantitative par chromatographie liquide à haute performance en phase inversée et détection par spectrophotométrie UV à 294 nm.

Identification and dosage of hydroquinone, methyl and benzyl ethers in cosmetic products for whitening the skin.
Effects of a topical preparation on some hair growth parameters, evaluated utilizing a morphometric computerized analysis
Authors: Pelfini C. , Fideli D. , Speziali A. , Vignini M.
Published: May 2007

Synopsis

The action of a topical preparation on some hair growth parameters has been evaluated. The morphometric computerized analysis applied to photographic images of a predetermined area (with shots after cutting and after 96 h) enabled an estimation of the percentage of elements in active growth phase compared to the total number, the length of all elements and that of the sole elements in active growth phase after 96 h and the growth with respect to the base values; statistically significant differences are observed before and after 60 days treatment.

L'évaluation des effets d'un topique sur quelques paramètres de la croissance des cheveux à travers une analyse morphométrique informatisée.
Epidermal lipids
Authors: YARDLEY H. J.
Published: May 2007

Synopsis

From the time an epidermal cell leaves the basal layer to the time it is desquamated, the cell lipids change dramatically, both qualitatively and quantitatively. The most abundant lipid class in basal cells is phospholipid with the remaining lipid being accounted for by roughly equal proportions of cholesterol, non‐esterified fatty acid, triacylglycerol and glycolipid: minor components include cholesteryl esters and ceramide. In contrast, approximately half of the lipid in a desquamated cell consists of ceramide, with the remainder consisting largely of cholesterol and non‐esterified fatty acid. Immediately before desquamation, small concentrations of cholesteryl sulphate and glycolipid have been found and there is evidence that these polar lipids are important components of the water barrier and also contribute towards the physical integrity of the lower part of the stratum corneum. The change in lipid content as cornification proceeds is no less dramatic than the change in lipid composition. A basal cell contains about 10 pg lipid, whereas a desquamated stratum corneum cell contains approximately six times this amount. The change in lipid composition of a cell undergoing cornification results, therefore, largely from de novo synthesis of lipid, especially cholesterol, non‐esterified fatty acid and ceramide.

Les lipides de l'épiderme
A study of the interaction of sodium dodecyl sulphate with the proteins of human heel stratum corneum
Authors: CONRADS ANDREA , ZAHN HELMUT
Published: May 2007

Synopsis

The aim of this research is to study the in vitro interaction of the anionic surfactant sodium dodecyl sulphate with human heel callus with special regard to the callus proteins.

The sorption of SDS by callus is analysed at different pH values, demonstrating the expected maximum binding of the anionic surfactant at low pH. In both surfactant and blank solutions, swelling of the callus pieces occurs but to different extents. The sorption of SDS by callus is accompanied by a loss of free amino acids and proteins. The protein composition of the callus residues after chemical treatment and of the corresponding treatment baths is examined by amino acid analysis and shows differences in the respective molar amino acid ratios. Results obtained with more specific techniques, such as gel electrophoresis and immunoblotting, demonstrate identical as well as different protein components in the treatment baths depending on the experimental conditions (pH, blank or SDS). Although effects due to the surfactant treatment are in principle more distinct than with blank experiments, those of the latter cannot be neglected.
Studies on the skin uptake and efflux kinetics of N‐phenyl‐p‐phenylenediamine: an aromatic amine intermediate
Authors: KHANNA S. K. , TEWARI PUSHPA , JOSHI ANIL , SINGH G. B.
Published: May 2007

Synopsis

N‐phenyl‐p‐phenylenediamine (N‐PPDA), an industrial intermediate and hair dye ingredient, has been implicated in a variety of toxic symptoms including cutaneous manifestations. However, the role of physiological factors that may determine and modify its absorption and transport within and through the skin is not fully understood. The present study reveals that N‐PPDA binds readily to skin showing saturation kinetics with Km and Vmax of 2.54 × 10−4 M and 4.76 μmol g−1 skin, respectively. The uptake was dependent upon the area of skin, concentration of the amine, exposure time, temperature and pH of the vehicle. Heat treatment facilitated the binding but temperatures abouv 50° caused significant lowering of the uptake, indicating the possible involvement of collagen matrix. Skin lipids also contributed in the binding of N‐PPDA. Bioinhibitors such as KCN, sodium arsenate, NaF, N‐ethylmaleimide, cycloheximide, iodoacetic acid and 2,4‐dinitrophenol had no effect on the uptake potential, suggesting it to be a non‐energy dependent process. Most of the skin‐bound N‐PPDA was effluxed through serum proteins reaching the target organs via systemic circulation.
Chemical reactions in perfume ageing
Authors: BLAKEWAY J. M. , FREY M. L. , LACROIX S. , SALERNO M. S.
Published: May 2007

The interactions between a typical range of perfume materials, alcohol, water, air, elevated temperatures and daylight have been studied. The changes of composition, acidity, peroxide content and the formation of new molecules were followed. The stabilizing effects of UV absorbers, antioxidants and sequestering agents were examined;

— the formation of acid reaction products was accelerated by air, temperature, daylight and the presence of natural products;

— peroxide formation was accelerated by heat and light and the presence of air; as the acidity increased, the peroxides decomposed;

— the acetalization of other aldehydes was accelerated by temperature and daylight and the presence of natural products up to 40% of certain aldehydes may be converted into acetals after 3 months at 37°C;

— many stereoisomerizations occur, e.g., transisoeugenol is converted up to 10% into the cis isomer after 3 months at 37°C and 58% in daylight;

— evaluation of antioxidants UV absorbers and sequestering agents showed a significant protection against deterioration only by EDTA dipotassium salt;

— ethanol was converted into acetaldehyde and its diethylacetal by peroxides present and formed on ageing up to 0.08%. Natural products accelerated this formation;

— the reaction between benzoyl peroxide and ethanol was shown to yield up to 63% of acetaldehyde+diethyl acetal whilst di‐t‐butyl peroxide gave only 23% under the same conditions.

These results go some way to explaining odour changes in perfume ageing.
Evaluation of an in vitro percutaneous permeation model with two oxidative hair dyes
Authors: BRACHER M. , FALLER C. , NOSER F. K.
Published: May 2007

Synopsis

The percutaneous permeation of two oxidative hair dyes was measured by means of pig skin in a flow‐through diffusion cell system entirely constructed from Teflon. Pig skin membranes were prepared by reducing full thickness skin with a dermatome to a more in vivo‐like barrier layer and their integrity was checked by measuring the steady‐state permeation of tritiated water. Initially, the inter‐ and intraindividual variability of percutaneous permeation was determined with an aqueous solution of 1‐(2′‐hydroxyethyl)‐amino‐3,4‐methylenedioxybenzene‐hydrochloride, an oxidative hair dye component. In the same way the proper flow rate of elution fluid through the receptor cell was found to be most favourable at 10 ml h‐1, the thickness of permeation membranes was fixed at 1 mm, and it was shown that storage of the skin at −20°C for up to 35 days did not change the permeability. The percutaneous permeation of the same hair dye component and of 4‐amino‐2‐hydroxymethylphenol‐hydrochloride was determined after application to pig skin membranes under practical conditions of hair dyeing. The in vitro skin permeation was in the same order of magnitude as results from comparable in vivo skin absorption studies in rats.

Perméation percutanée in vitro de colorants d'oxydation pour cheveux
Henna as an antimicrobial agent
Authors: GUERRIER C. J. W. , ABDULWAHAB A. , BASRI N. , REVILL S.
Published: May 2007

Synopsis

Powdered henna leaf as used as a cosmetic in the Middle East has been tested for its antimicrobial qualities against a series of common organisms. It has been shown to be effective against bacteria and some common fungi, but to have only limited potency against Candida albicans and Trichosporon beigelii.

Le henne utilisé comme agent anti‐microbien

La poudre de henné, préparée à partir des feuilles séchées de Lawsonia inermis, est largement utilisée comme produit cosmétique au Moyen et en Extrěme‐Orient. Elle a également une longue renommée en tant qu'agent antiseptique et conservateur, utilisée par les pharaons égyptiens pour la conservation des momies. Le henné est également connu pour de prévenir l'infection de la peau et du cuir chevelu. C'est pourquoi il a été décidé de tester son pouvoir d'inhibition sur les germes pathogènes communs en laboratoire. On a d'abord testé la stérilité de la poudre de henné; on a trouvé qu'elle contenait à la fois des bacilles non‐pathogènes et l'Aspergillus niger, mais aucun autre microbe pathogène humain reconnu.

On a démontré qu'une suspension de 10% de poudre de henné sèche du commerce dans de l'eau distillée stérile inhibe la prolifération de Pseudomonas pyocyanea, Escherichia coli, Straphylococcus aureus, Microsporum gypseum, Microsporum canis et Trichophyton mentagrophytes en culture. Le succès a été moins flagrant pour inhiber la prolifération des Trichosporon beigelii et l'opération a échoué pour le Candida Albicans. Le henné utilisé en solution sur la peau humaine perd ses propriétés inhibitrices à l'encontre des germes précités. On en a donc conclu que le henné a des propriétés anti‐microbiennes, mais avec un spectre limité.
Surfactant‐induced fluorescence changes in fluorescein dye
Authors: MATHUR A. K. , AGARWAL CHITRA , PANGTEY B. S. , SINGH A. , GUPTA B. N.
Published: May 2007

Synopsis

Addition of non‐ionic surfactants revealed changes in the visible absorbance and fluorescence characteristics of fluorescein dyes. Non‐ionic surfactants induced a shift in Δmax, towards shorter wavelengths along with a decrease in absorbance of the dye. On the other hand, addition of anionic surfactants induced a shift of Δmax, towards longer wavelengths along with enhancement in absorbance and fluorescence. The absorbance value decreased initially, but increased on further addition of cationic surfactant, whereas fluorescence increased initially but decreased on further addition of cationic surfactant. These changes are attributed to the interaction of surfactant micelle with dye molecules, resulting in change of the coloured quinoid form to the colourless lactone form and vice versa.
A method for the determination of the carbon chain length composition of amine oxides.
Authors: LANGLEY N. A. , SUDDABY D. , COUPLAND K.
Published: May 2007

Synopsis

Alkylamine oxides and alkylamidopropyldimethylamine oxides belong to an important group of surfactant materials. They are used extensively in formulations for cosmetics, toiletries and household products.

Although there are numerous analytical methods available to evaluate physical and chemical properties of these compounds, there remains a demand for a qualitative method for the determination of the carbon chain length composition.

Amine oxides cannot be analysed directly by gas liquid chromatography (GLC) as they decompose at temperatures above 100°C to give the terminal alkenes and tertiary amines. However, amine oxides can be analysed by GLC if they are first reduced to the tertiary amines. Examples of each type of amine oxide were reduced with triphenylphosphine in boiling glacial acetic acid between 1 and 1.5 h.

In this paper a rapid qualitative analytical procedure is described.
In vitro release of propranolol from oil/water microemuisions
Authors: GASCO M. R. , CARLOTTI M. E. , TROTTA M.
Published: May 2007

Synopsis

Oil/water (o/w) microemulsions containing propranolol were studied. Isopropylmyristate was used as the oil, Tween 60 as a surfactant, butanol as a co‐surfactant and a buffer of pH 6.5 for the continuous phase. The lipophilicity of propranolol was enhanced by formation of lipophilic ion‐pairs to obtain a disperse phase that could act as a reservoir; octanoic acid was used as counter‐ion. The diffusion rates of propranolol from microemulsions through a hydrophilic membrane decreased as the concentration of octanoic acid increased. The apparent permeability constant, determined at the beginning of the experiment, was 2.9 × 10−9 cm s−1 for propranolol alone and diminished until 3.5 × 10−10 cm s−1 in the presence of octanoic acid, at a concentration of 16.4 times that of propranolol.
Applications of ternary systems in specific cosmetic formulations
Authors: COMELLES F. , MEGIAS V. , SÁNCHEZ J. , PARRA J. L. , COLL J. , BALAGUER F. , PELEJERO C.
Published: May 2007

Synopsis

The study of ternary systems leads to the understanding of the physico‐chemical aspect and allows the contribution of the different components to a cosmetic formulation to be developed.

The present investigation was centred in the zone of transparent get belonging to a previously studied ternary system containing a broad variety of different structural compositions. The possibility of including an active sunscreen as well as the ability to increase the water content of the gel was studied.

The microscopical study of the compositions with polarized light allowed us to assign the corresponding different structures. A correlation between these structures and their physico‐chemical properties, with special emphasis to rheology, has been established.
Analysis of pigmentation in human skin: quantification of ultraviolet ray images by digital image processing
Authors: ARAI SEIICHI , HARA YUKIKO , MIMURA KUNIO , NAGASAWA HISANAO , NISHIJIMA YASUSHI
Published: May 2007

Synopsis

A new method for quantifying pigmentation with transformation of ultraviolet ray images into digital images has been developed. Utilizing this method, the distribution of pigments deposited in healthy Japanese subjects has been investigated. The following characteristics of pigmentations have now been obtained as follows:

— the amount of total pigmentation areas and the frequency of appearance of large pigmented areas increase with ageing;

— in young and middle age groups, women have more pigmentation than men, whereas in old age, this trend is reversed;

— the amount of pigmentation is greatest on the front of the cheeks and the least on the forehead;

— pigmentation areas darken in summer, and the amount of pigmentation and number of pigmented areas increase in summer.

Interestingly enough, a correlation between ‘ultraviolet rays in daily life' and ‘the pigmentation in human skin' is strongly suggested.
Comparison of diffusion by anionic surfactants through cellulose acetate and collagen membranes
Authors: GARCÍA RAMÓN M. T. , RIBOSA I. , LEAL J. SANCHEZ , PARRA J. L.
Published: May 2007

Synopsis

From a dermatological point of view, it is important to know what is the irritation potential of surfactants on human skin. Recent research trends have been oriented towards the establishment of new ‘in vitro’ techniques that will avoid animal experimentation.

In this paper, some results on the rate of diffusion of different anionic surfactants through both cellulose acetate and collagen membranes are described. A correlation between results of diffusion through the protein membrane and results published on the same surfactants and their irritation potential during ‘in vivo’ experiments appears possible.
Studies on the mutagenicity of aniline in association with norharman in the Salmonella/mammalian microscome assay
Authors: SHAHIN MAJDI M.
Published: May 2007

Synopsis

The mutagenicity of aniline was investigated in association with norharman using Aroclor 1254–induced and uninduced liver S9 fractions. The non‐mutagenicity of aniline in the Salmonella/mammalian microsome test was also re‐examined under various experimental conditions. Aniline caused no increase in the number of revertants per plate in Salmonella typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98 at concentrations of up to 5000 μg/plate. S9 preparations from rat liver, hamster liver, rat spleen, or hamster spleen were all ineffective in activating aniline to a mutagen in tests using various concentrations of S9 in S9 mix. In contrast to the results with aniline alone, mixtures of aniline and norharman were mutagenic in strain TA1538 in the presence of S9 fractions from liver of rats pretreated with Aroclor 1254. The observed mutagenicity decreased as a function of the concentration of S9 in S9 mix. In the presence of uninduced liver S9 preparations, the mutagenicity of the mixture of the two compounds was slight (three‐fold).
The ultraviolet microscopic transmission characteristics of human stratum corneum
Authors: PHILP J. , ALLCOCK C.
Published: May 2007

Synopsis

This study has evaluated the ultraviolet light transmission characteristics of human stratum corneum at the single cell level using a low light level video microscope to measure the mean percentage transmission of light at different wavelengths and the variation in transmission across the stratum corneum. Stratum corneum was isolated by an enzymic technique and examined on a low light level UV video microscope. Quantitative evaluation of the transmitted monochromatic light for the underside of the layer was measured directly using a Kontron UNIPS image processor or indirectly with a Quantimet 920 image processor after video recording. Transmission distribution histograms were obtained from samples of stratum corneum taken from human breast, scalp, abdomen and leg. Mean transmission values were also derived and compared with diffuse transmission values obtained using the same tissue mounted on an integrating sphere. The UV microscopic transmission characteristics of enzyme separated stratum corneum clearly demonstrated that this structure was not an ideal diffuser. Uniform light intensity on the surface of the stratum corneum led to areas of transmitted intensity in close proximity that differed by factors ofthree to six fold, e.g. between regions of high (>70%) and low (<20%) brightness. However, the average transmission was found to be compatible with published data obtained by diffuse transmission spectrophotometry, taking into account the enhanced transmission arising from stratum corneum immersion in phosphate buffered saline. This was confirmed by the elevated values obtained by diffuse transmission spectrophotometry in this study for samples of stratum corneum prepared for UV microscopy being higher than these found in published data. It is obvious from these findings that viable cells in the epidermis are not exposed to a uniform incident light intensity even when this is true for the surface of skin. Studies of skin response to ultraviolet light at the single cell level must take account of the possibility of preferential exposure of specific sites in any subsequent explanation of cell sensitivity. This is in addition to the already well established cell cycle dependent ultraviolet sensitivity.
Portable erythema meter and its application to use in human skin
Authors: PEARSE A. D. , EDWARDS C. , HILL S. , MARKS R.
Published: May 2007

Synopsis

In 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 assessments.
Molecular basis of photocontact allergy
Authors: PENDLINGTON R. U. , BARRATT M. D.
Published: May 2007

Synopsis

Photocontact 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 T4CS photoallergy.
Efficiency and usability of silicone surfactants in emulsions
Authors: SMID‐KORBAR J. , KRISTL J. , STARE M.
Published: May 2007

Synopsis

The critical micelle contration (CMC) of silicone surfactants was determined to provide their optimal efficiency in emulsion systems. The lowest CMC value was found for the amphionic polysiloxane polyorganobetaine copolymer, which is undoubtedly the consequence of electrostatic repulsion preventing the aggregation of ionized molecules. Also the nonionic surfactants (polydimethyl siloxane polyethers) showed some differences: the surfactant with polyethylene oxide side chain is more effective compared to the polyethylene‐polypropylene oxide side chain.

The results of miscibility testing of silicone surfactants with common components of emulsions and creams confirm that not only silicone oils, but also silicone surfactants, should be considered as both explicitly hydrophobic and non lipophilic.

The stability of emulsions containing silicone surfactants prepared by cold emulsification supported the incorporation of polyelectrolyte sodium carboxymethylcellulose, which increased viscosity of the continuous phase and prevented coalescence.

The physical stability testing of prepared emulsions confirms that the used methods ‐ centrifugation, particle size analysis and the observation of ageing at room (20–25°C) and elevated temperature (40°C) ‐ give comparable results.
HPLC determination of thioglycolic acid and other aliphatic thiols in cosmetic formulations using ethacrynic acid as precolumn derivatization reagent
Authors: CAVRINI V. , ANDRISANO V. , GATTI R. , SCAPINI G.
Published: May 2007

Synopsis

Limits imposed on the usage of thioglycolic acid, its salts and esters in cosmetic formulations require selective and sensitive analytical methods for their determination. In this study a convenient and reliable method based on high‐performance liquid chromatography (HPLC) has been developed. The method involves a precolumn reaction of the thiol compounds with ethacrynic acid to give thiol adducts which can be separated by reversed‐phase liquid chromatography and detected at λ= 273 nm.

The derivatization reaction proved to be quantitative under mild conditions (20 min at pH 7.4 and room temperature) and the chromatographic conditions allowed thioglycolic acid, glyceryl monothioglycolate, thiolactic acid, and thioglycolic acid ethyl ester to be discriminated.

The proposed method was successfully applied to the analysis of commercial cosmetic formulations containing thioglycolic acid and glyceryl monothioglycolate, fulfilling the requirements of a general and selective method for the analysis of aliphatic thiols in cosmetics.
Methods for assessment of cutaneous ageing
Authors: MARKS R.
Published: May 2007

Quantitative assessment of skin ageing is necessary for the evaluation of age modifying treatments. The particular method used must depend on the target of the intended treatment. It should also clearly distinguish between the degree of chronic environmentally‐induced trauma to the skin (predominantly photoageing) and the intrinsic ageing process. However, it is clear that no one measure will be adequate to define the extent of cutaneous ageing. Broadly speaking, the techniques available are either invasive or non‐invasive. Both have their uses. For example, topically applied retinoic acid 0.05% has been shown to increase epidermal thickness and decrease stratum corneum replacement time, using an invasive technique to determine the value for the first and a non‐invasive method to evaluate the second. Virtually all aspects of skin structure and function change with age. However, because of the importance with regard to appearance, some measure of solar elastotic degenerative change should be made. Profilometry techniques and ultrasound determination of skin thickness, as well as measurement of skin colour, may all have their use for this purpose.
Ethics of human testing
Authors: SALTER D.C.
Published: May 2007

Synopsis

What should one do, and why? Anyone asking such questions ‐ and everyone does so hundreds of times each day ‐ is concerned with ethics.

Product development and testing raise many ethical questions. Particularly since the rise of ‘green consumerism’, these are of increasing concern to people outside the cosmetics industry, and so should be of interest to those inside it.

The major problem seems to be that of reaching agreement on moral and ethical issues. Overcoming this problem involves investigating what is meant by ‘ethics’, and how decisions depend not on facts but on ‘facts‐as‐perceived’. These in turn depend on many factors, with one's philosophy being the most fundamental. The range of philosophical options is reviewed and it is proposed that wider discussion is the only just way to achieve agreement. Yet some things are not negotiable. There are certain key moral concepts in terms of which discussion must take place for it to be relevant. In ethics of human testing, ‘respect for others’, that is, avoiding exploitation, is the principal one. Some synthesis of the key moral concepts like that of Immanuel Kant is therefore recommended as the soundest and most widely acceptable basis for the necessary discussion.

Defining the responsible use of human subjects covers a range of issues, moral, historical, legal and professional. For example, there may be ethical difficulties in deliberate damage induction as in SPF and irritancy testing. But above all, to avoid exploitation, there is a moral and also a legal requirement that subjects are truly volunteers. This is the basis of the concept of ‘informed consent’, required but not generally explained in current professional codes of practice. It is unjustified to exploit those who may be under duress, such as ‘in‐house volunteers' and those with low incomes. Hence in conclusion, criteria for obtaining valid informed consent are briefly reviewed.

By considering issues such as these, we can help ensure that cosmetic scientists are true professionals, that is, those who recognise and are concerned with the ethical basis of their work.
Transparent formulations of a liposoluble sunscreen agent in an aqueous medium
Authors: COMELLES F. , PARRA J.L. , FERRANDO C. , CAELLES J. , SÁNCHEZ J.
Published: May 2007

Synopsis

Transparent formulations of a liposoluble sunscreen in an aqueous medium were studied, taking into account the different chemicals of a selected system situated in the vertices of a regular tetrahedron: sunscreen agent, co‐solvent, (surfactants ± mineral oil) mixture (in the tetrahedron base) and water as the fourth component. Several compositions were selected at optimized component ratios after which water was added progressively. Clear gel and liquid compositions were obtained yielding a sunscreen agent that it suitable for conventional use. The physico‐chemical properties of some compositions were assessed in terms of water/sunscreen agent content.
Studies on the interaction of p‐phenylene diamine with phospholipids
Authors: MISRA V. , GUPTA V. , VISWANATHAN P.N.
Published: May 2007

Synopsis

In vitro studies on the interaction of phospholipids with p‐phenylene diamine, a major component of hair dyes, were undertaken. Thin layer and molecular sieving chromatography along with phosphorus estimation and spectral characterization suggested the possibility of p‐phenylene diamine and its biotransformation products combining with lipophilic biomolecules.
A new methodology for testing chemicals and drugs on cell activity
Authors: MAFTAH A. , PETIT J. M. , LEPRAT P. , RATINAUD M. H. , JULIEN R.
Published: May 2007

Synopsis

A new method for testing the effects of cosmetics and various chemicals on cell activity is described. It is based on the study of mitochondria compartments and combines the use of fluorescent probes which are accumulated in a potential‐dependent (Rhodamine 123) or potential‐independent (Nonyl Acridine Orange) manner with flow cytometric analysis. Measured fluorescences allow the determination of a new parameter indicating mitochondria efficiency.

This new methodology for the evaluation of cell activity has been applied in three different situations: during cell ageing, during cell cycle and when cells are in the presence of drugs.
Dowicil 200 Stability test: chemical and microbiological studies
Authors: SEMENZATO A. , BENASSI C.A. , ROSSI G. , BETTERO A. , LUCCHIARI M. , CERINI R.
Published: May 2007

Synopsis

The stability of the formaldehyde‐releaser preservative Dowicil 200 has been investigated. The studies were carried out on cosmetic emulsions preserved with different concentrations of Dowicil 200, stored in the dark at 45°C or 25°C. The degree of microbiological activity was tested with respect to S. aureus, P. aeruginosa, E. coli and A. niger using the agar diffusion and challenge tests. The chemical stability was evaluated by HPLC in the reverse phase mode. A significant preservative instability was observed.
Les émulsions multiples
Authors: DE LUCA M. , ROCHA‐FILHO P. , GROSSIORD J.L. , RABARON A. , VAUTION C. , SEILLER M.
Published: May 2007

Synopsis

The main purpose of this article is to define multiple emulsions, their preparation (new materials and manufacturing processes) methods of characterisation and analysis, and their applications in cosmetology and pharmacy.

The second part is devoted to a presentation of the investigation in our laboratory into the optimal manufacturing process to provide stable formulations. The study of release mechanisms from such formulations mainly shows a breakdown of multiple droplets which could be controlled by variation of solute concentration.
Prophylaxis of Striae gravidarum with a topical formulation. A double blind trial
Authors: MALLOL J. , BELDA M.A. , COSTA D. , NOVAL A. , SOLA M.
Published: May 2007

Synopsis

A prophylactic antistriae cream (Centella asiatica extract, α‐tocopherol, and collagen‐elastin hydrolisates) was assessed by a double blind trial in 80 pregnant women.

In the placebo group 22 women (56%) presented striae, whereas in the treated group only 14 women (34%) developed striae in this pregnancy; this difference was significant (p < 0.05; χ2 test). An arbitrary score was designed to assess the intensity of striae (from 0 to 3); this score was 1.42 (sd 0.5) in the treated group and 2.13 (sd 1.32) in the placebo group and this difference was also significant (p= 0.014; Mann–Whitney test).

In women with a history of striae during puberty, the active cream induced a significant absolute prevention in 89% of the cases whereas in the placebo group all the women developed striae (p= 0.00014; χ2 test).
Ethylene formation from methionine as a method to evaluate oxygen free radical scavenging and metal inactivation by cosmetics
Authors: GALEY J.‐B. , MILLECAMPS F. , NGUYEN Q.‐L.
Published: May 2007

Synopsis

It has been proposed that oxygen free radicals are involved in skin aging. This paper describes a new method for the evaluation of oxygen free radical scavenging by cosmetic products. It is based on the measurement, by gas chromatography, of ethylene produced during the oxidation of methionine by the hydroxyl radical. OH· is produced by an iron catalyzed superoxide‐driven Fenton reaction in which superoxide is obtained by photochemical oxygen reduction. The cosmetic is applied, together with methionine, riboflavine, NADH, FeCl3 and EDTA, on a glass microfibre filter and submitted to UVA exposure through a quartz cell. Ethylene is then measured from aliquots of the atmosphere inside the cell. Catalase or Desferal completely inhibits ethylene production. SOD or high concentrations of hydroxyl radical scavengers (Mannitol, DMSO etc.) afford a partial protection. Thus the efficiency of O2−·, H2O2 and OH· scavengers and iron chelators can be measured. The main advantage of this test is that it is performed in conditions which simulate skin during UV exposure (e.g. air and UV exposed thin layer). Furthermore, as it is non‐invasive, it can also be applied to human skin in vivo.
Determination of α‐bisabolol and d‐panthenol in cosmetic products by gas chromatography
Authors: ANDRE D. , VERITE P. , DUCLOS R. , ORECCHIONI A.M. , FAILLY F.
Published: May 2007

Synopsis

α‐bisaboloi and d‐panthenol are used in many cosmetic preparations, respectively, for their anti‐inflammatory and regenerating properties. Their quantitative determination was an important element of their evaluation in these emulsions. Their concentration has been determined by gas chromatographic techniques, using a flame ionization detector. In both cases, the internal standards have been chosen for their compatibility with the analysis of extracted substances.

Owing to the complexity of the cosmetic formulations, a preliminary extraction of α‐bisabolol and d‐panthenol was necessary. For the two substances the preparative separation was based on a liquid–liquid extraction. After dissolving the emulsion in methanol and diluting it with an aqueous buffer solution α‐bisabolol was then extracted by ethyl acetate and d‐panthenol by ethyl formate.
Simulated consumer exposure to dimethyl ether and propane/butane in hairsprays
Authors: HARTOP P.J. , COOK T.L. , ADAMS M.G.
Published: May 2007

Synopsis

The potential human exposures from use of dimethyl ether (DME) and ‘liquefied petroleum gas’(LPG) arising from use in hairsprays have been assessed. DME and LPG concentrations were measured in the ‘breathing zone’ of an experimental manikin and an ‘accompanying child’ designed to simulate human use of hairsprays in a domestic situation and in the breathing zone of a ‘stylist’ and ‘customer’ under salon conditions. Results were expressed as the 10 min time weighted average in the air (TWA10) and as the peak concentration in the breathing zone of the ‘user’.

Following a 10s use of hairspray containing 50% DME or 26% LPG, TWA10 values for an adult user in a closed room (volume 21 m3) were on average 114 ppm and 73 ppm respectively. The child TWA10 values were 89 ppm (DME) and 80 ppm (LPG). Leaving the door open during spraying did not significantly alter these values. The peak concentrations measured in the user breathing zone were 1577 ppm of DME and 671 ppm of LPG. Simulated salon use of a hairspray gave a calculated value of 55 ppm DME and 88 ppm LPG for the stylist over an 8 h working period.
Optimization of emulsions
Authors: CARLOTTI M.E. , CARPIGNANO R. , GASCO M.R. , TROTTA M.
Published: May 2007

Synopsis

The optimization of three emulsions with predetermined components was performed by the aid of experimental design. Three different surfactants were compared: the salts of hexadecylhydrogenphosphate with diethanolamine, lysine and arginine respectively. Optimized microemulsions showed quite high stabilities towards centrifugation (30–60 min at 7000 rpm). The results showed that the counter‐ion can affect the composition and stability of an emulsion.
The use of Fourier transform infra‐red spectroscopy in the study of the surface chemistry of hair fibres
Authors: JOY M. , LEWIS D.M.
Published: May 2007

Synopsis

Human hair keratin is susceptible to damage by both chemical and physical agencies. Oxidative damage can now be assessed by the use of Fourier transform infra‐red (FTIR) spectroscopy.

Analysis may be performed using the following techniques; diffuse reflectance, attenuated total reflectance and microspectrophotometry. This latter technique is made possible by the coupling of a research grade microscope to the optical bench of the FTIR spectrometer.

The computing power necessary to operate the FTIR allows data to be mathematically manipulated. Derivative spectra obtained in this manner allow small peaks obscured by the close proximity of large peaks to be resolved.

Analysis of single fibres treated with hydrogen peroxide or metabisulphite solutions showed the formation of cysteic acid and cysteine‐S‐sulphonate respectively.

Second order derivative spectroscopy allowed a profile of the oxidative damage from the root to tip of naturally weathered hair to be constructed.
Exposure to paraphenylendiamine in hairdressing parlours
Authors: GAGLIARDI L. , AMBROSO M. , MAVRO J. , FURNO F. , DISCALZI G.
Published: May 2007

Synopsis

A certain number of hairdressing parlour employers have been taken to court because their employees allegedly suffered from lung allergies caused by the vapours from PPD (paraphenylendiamine) which allegedly developed when applying hair dyes. These conclusions may be reached if the specific hazards of the rubber and particularly leather and fur dyeing industry are extrapolated as is widely reported in literature, to hairdressing employees. The purpose of this study is to assess the actual exposure rate to PPD vapours of hairdressing employees during a working day, on the basis of the type and characteristics of the salon (small, medium and large), the number of dye applications per day and the chemical‐physical characteristics of the oxidation dyes. The results prove that, even under the hypothesis of experimental conditions pushed to the extreme, it is not reasonable to speak of exposure to PPD through the lungs of hairdressing employees.
Comparative assessment of talc slip using a sensory analysis technique
Authors: MacLENNAN A. , SHAW R. , JONES L.
Published: May 2007

Synopsis

A technique was developed to evaluate the relative slip of ten test talcs and two control talcs (one with known good slip and one with known poor slip properties). The study was conducted under double‐blind conditions with a naive panel of 19 subjects, who with minimal training ranked the 12 talcs. The rankings identified were in line with expectations. Such sensory analysis could be applied in this cost‐effective manner to the evaluation and comparison of many properties of cosmetics and toiletries.
Dosage de l'octyl triazone dans les produits cosmétiques solaires
Authors: Et M. HERPOL‐BORRHMANS , MASSE M. O.
Published: May 2007

Dosage of octyl triazone in cosmetic sunscreen products.

The method describes the quantitative determination of octyl triazone [2, 4, 6‐trianilino‐p‐(carbo‐2′‐ethylhexyl‐1′‐oxy)‐1, 3, 5‐triazine] in cosmetic sunscreen products.

The sample is suspended in tetrahydrofuran and after appropriate treatment the determination is made by HPLC.
Preparation of an oakmoss absolute with reduced allergenic potential
Authors: EHRET C. , MAUPETIT P. , PETRZILKA M. , KLECAK G.
Published: May 2007

Synopsis

Oakmoss absolute, an extract of the lichen Evernia prunastri, is known to cause allergenic skin reactions due to the presence of certain aromatic aldehydes such as atranorin, chloratranorin, ethyl hematommate and ethyl chlorohematommate.

In this paper it is shown that treatment of Oakmoss absolute with amino acids such as lysine and/or leucine, lowers considerably the content of these allergenic constituents including atranol and chloratranol. The resulting Oakmoss absolute, which exhibits an excellent olfactive quality, was tested extensively in comparative studies on guinea pigs and on man. The results of the Guinea Pig Maximization Test (GPMT) and Human Repeated Insult Patch Test (HRIPT) indicate that, in comparison with the commercial test sample, the allergenicity of this new quality of Oakmoss absolute was considerably reduced, and consequently better skin tolerance of this fragrance for man was achieved.