bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro release of propranolol from oil/water microemuisions
Authors: GASCO M. R. , CARLOTTI M. E. , TROTTA M. 
Published: May 2007

SynopsisOil/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

SynopsisThe 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

SynopsisA 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

SynopsisFrom 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

SynopsisThe 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

SynopsisThis 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

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

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

SynopsisThe 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

SynopsisLimits 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

SummaryQuantitative 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

SynopsisWhat 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

SynopsisTransparent 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

SynopsisA 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

SynopsisThe 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

SynopsisThe 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

SynopsisA 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

SynopsisIt 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

Synopsisα‐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.