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Hair Color (hair + color)
Selected AbstractsDevelopment of a Novel Oxidative Hair Color Based on a System with an Optimized Ratio of Higher Alcohol to Cationic SurfactantINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2006T. Yamashita Oxidative hair color, the most commonly used for coloring hair, is characterized by its bleaching effect. This effect enables dark hair to be dyed in various bright colors. In order to enhance this bleaching effect, the concentration of either the alkalizing or oxidizing agent in the hair color base is generally increased. However, this method causes chemical damage to the hair. With the aim of finding methods to obtain an improved bleaching effect without increasing the amount of bleaching ingredients, the authors investigated the permeation mechanism. Cationic bases showed the highest bleaching effect and allowed greater penetration, permitting bleaching ingredients to enter the cortex of the hair more easily and diffuse more quickly. In addition, the molar ratios of higher alcohol (A) to cationic surfactant (C) as a function of the bleaching effect were also evaluated. The results showed an optimum range for this A/C ratio. The smoothness of the hair was also evaluated, revealing an optimum range for the A/C ratio. Based on these findings, a product with an A/C ratio that maximizes the bleaching effect and the smoothness of the hair was successfully developed. Comparison of this newly developed product with a conventional product verified that the new product has a greater bleaching effect and gives a beautiful depth of color while maintaining the silky smoothness of the texture of the hair. Part of this study was presented at the 23rd IFSCC Congress 2004, Orlando, Florida USA. [source] Genetic variants in pigmentation genes, pigmentary phenotypes, and risk of skin cancer in CaucasiansINTERNATIONAL JOURNAL OF CANCER, Issue 4 2009Hongmei Nan Abstract Human pigmentation is a polygenic quantitative trait with high heritability. Although a large number of single nucleotide polymorphisms (SNPs) have been identified in pigmentation genes, very few SNPs have been examined in relation to human pigmentary phenotypes and skin cancer risk. We evaluated the associations between 15 SNPs in 8 candidate pigmentation genes (TYR, TYRP1, OCA2, SLC24A5, SLC45A2, POMC, ASIP and ATRN) and both pigmentary phenotypes (hair color, skin color and tanning ability) and skin cancer risk in a nested case-control study of Caucasians within the Nurses' Health Study (NHS) among 218 melanoma cases, 285 squamous cell carcinoma (SCC) cases, 300 basal cell carcinoma (BCC) cases and 870 common controls. We found that the TYR Arg402Gln variant was significantly associated with skin color (p -value = 7.7 × 10,4) and tanning ability (p -value = 7.3 × 10,4); the SLC45A2 Phe374Leu variant was significantly associated with hair color (black to blonde) (p -value = 2.4 × 10,7), skin color (p -value = 1.1 × 10,7) and tanning ability (p -value = 2.5 × 10,4). These associations remained significant after controlling for MC1R variants. No significant associations were found between these polymorphisms and the risk of skin cancer. We observed that the TYRP1 rs1408799 and SLC45A2 1721 C>G were associated with melanoma risk (OR, 0.77; 95% CI, 0.60,0.98 and OR, 0.75; 95% CI, 0.60,0.95, respectively). The TYR Ser192Tyr was associated with SCC risk (OR, 1.23; 95% CI, 1.00,1.50). The TYR haplotype carrying only the Arg402Gln variant allele was significantly associated with SCC risk (OR, 1.35; 95% CI, 1.04,1.74). The OCA2 Arg419Gln and ASIP g.8818 A>G were associated with BCC risk (OR, 1.50; 95% CI, 1.06,2.13 and OR, 0.73; 95% CI, 0.53,1.00, respectively). The haplotype near ASIP (rs4911414[T] and rs1015362[G]) was significantly associated with fair skin color (OR, 2.28; 95% CI, 1.46,3.57) as well as the risks of melanoma (OR, 1.68; 95% CI, 1.18,2.39) and SCC (OR, 1.54; 95% CI, 1.08,2.19). These associations remained similar after adjusting for pigmentary phenotypes and MC1R variants. The statistical power of our study was modest and additional studies are warranted to confirm the associations observed in the present study. Our study provides evidence for the contribution of pigmentation genetic variants, in addition to the MC1R variants, to variation in human pigmentary phenotypes and possibly the development of skin cancer. © 2009 UICC [source] Pigmentary characteristics and moles in relation to melanoma riskINTERNATIONAL JOURNAL OF CANCER, Issue 1 2005Linda Titus-Ernstoff Abstract Although benign and atypical moles are considered key melanoma risk factors, previous studies of their influence were small and/or institution-based. We conducted a population-based case-control study in the state of New Hampshire. Individuals of ages 20,69 with an incident diagnosis of first primary cutaneous melanoma were ascertained through the New Hampshire State Cancer Registry. Controls were identified through New Hampshire driver's license lists and frequency-matched by age and gender to cases. We interviewed 423 eligible cases and 678 eligible controls. Host characteristics, including mole counts, were evaluated using logistic regression analyses. Our results showed that pigmentary factors, including eye color (OR = 1.57 for blue eyes compared to brown), hair color (OR = 1.85 for blonde/red hair color compared to brown/black), freckles before age 15 (OR = 2.39 for freckles present compared to absent) and sun sensitivity (OR = 2.25 for peeling sunburn followed by no tan or a light tan and 2.42 for sunburn followed by tan compared to tanning immediately), were related to melanoma risk; these associations held after adjustment for sun-related factors and for moles. In analyses confined to skin examination participants, the covariate-adjusted effects of benign and atypical moles were moderately strong. Compared to 0,4 benign moles, risk increased steadily for 5,14 moles (OR = 1.71), 15,24 moles (OR = 3.55) and , 25 moles (OR = 4.33). Risk also increased with the number of atypical moles; compared to none, the ORs for having 1, 2,3, or , 4 atypical moles were 2.08, 1.84 and 3.80, respectively. Although risk was highest for those with multiple benign and atypical moles, the interaction was not of statistical significance. Our findings, arising from the first population- and incidence-based study to evaluate atypical moles in relation to melanoma risk, confirm the importance of host susceptibility, represented by pigmentary factors and the tendency to develop benign or atypical moles, in the etiology of this disease. © 2005 Wiley-Liss, Inc. [source] Use of image analysis techniques for objective quantification of the efficacy of different hair removal methodsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2007S. Bielfeldt In the field of consumer-used cosmetics for hair removal and hair growth reduction, there is a need for improved quantitative methods to enable the evaluation of efficacy and claim support. Optimized study designs and investigated endpoints are lacking to compare the efficacy of standard methods, like shaving or plucking, with new methods and products, such as depilating instruments or hair-growth-reducing cosmetics. Non-invasive image analysis, using a high-performance microscope combined with an optimized image analysis tool, was investigated to assess hair growth. In one step, high-resolution macrophotographs of the legs of female volunteers after shaving and plucking with cold wax were compared to observe short-term hair regrowth. In a second step, images obtained after plucking with cold wax were taken over a long-term period to assess the time, after which depilated hairs reappeared on the skin surface. Using image analysis, parameters like hair length, hair width, and hair projection area were investigated. The projection area was found to be the parameter most independent of possible image artifacts such as irregularities in skin or low contrast due to hair color. Therefore, the hair projection area was the most appropriate parameter to determine the time of hair regrowth. This point of time is suitable to assess the efficacy of different hair removal methods or hair growth reduction treatments by comparing the endpoint after use of the hair removal method to be investigated to the endpoint after simple shaving. The closeness of hair removal and visible signs of skin irritation can be assessed as additional quantitative parameters from the same images. Discomfort and pain rating by the volunteers complete the set of parameters, which are required to benchmark a new hair removal method or hair-growth-reduction treatment. Image analysis combined with high-resolution imaging techniques is a powerful tool to objectively assess parameters like hair length, hair width, and projection area. To achieve reliable data and to reduce well known image-analysis artifacts, it was important to optimize the technical equipment for use on human skin and to improve image analysis by adaptation of the image-processing procedure to the different skin characteristics of individuals, like skin color, hair color, and skin structure. [source] Color simulation method for accurate prediction of resulting dyed hair colorINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2007T. Takahashi When choosing hair dyes, it is natural for the user to assume that the final hair color will resemble the color indicated on the product container or color chart. Often, however, the result is quite different. The ability to accurately predict resulting hair color after dyeing is essential, but not easy to attain because hair varies significantly from person to person. In this paper, a new method for predicting the dyed hair state is proposed. Our method is based on a model, where the observed final color consists of contribution from three layers of the hair structure: a melanin-containing layer, a bleached layer and a pigment-colored layer. A method for predicting the final color from responses in each layer is introduced. In this method, response formulae for each layer are derived from the energy balance, and the predicted hair color after dyeing is obtained by calculating the each equation assuming that the hair state before dyeing is solely because of the contribution from the melanin-containing layer. In addition, a small measuring apparatus utilizing this prediction method was developed and the effectiveness of our method demonstrated by data obtained before and after the hair dyeing. [source] Development of a Novel Oxidative Hair Color Based on a System with an Optimized Ratio of Higher Alcohol to Cationic SurfactantINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2006T. Yamashita Oxidative hair color, the most commonly used for coloring hair, is characterized by its bleaching effect. This effect enables dark hair to be dyed in various bright colors. In order to enhance this bleaching effect, the concentration of either the alkalizing or oxidizing agent in the hair color base is generally increased. However, this method causes chemical damage to the hair. With the aim of finding methods to obtain an improved bleaching effect without increasing the amount of bleaching ingredients, the authors investigated the permeation mechanism. Cationic bases showed the highest bleaching effect and allowed greater penetration, permitting bleaching ingredients to enter the cortex of the hair more easily and diffuse more quickly. In addition, the molar ratios of higher alcohol (A) to cationic surfactant (C) as a function of the bleaching effect were also evaluated. The results showed an optimum range for this A/C ratio. The smoothness of the hair was also evaluated, revealing an optimum range for the A/C ratio. Based on these findings, a product with an A/C ratio that maximizes the bleaching effect and the smoothness of the hair was successfully developed. Comparison of this newly developed product with a conventional product verified that the new product has a greater bleaching effect and gives a beautiful depth of color while maintaining the silky smoothness of the texture of the hair. Part of this study was presented at the 23rd IFSCC Congress 2004, Orlando, Florida USA. [source] Genetic determinants of hair color and parkinson's disease risk,ANNALS OF NEUROLOGY, Issue 1 2009Xiang Gao MD Objective A history of melanoma is associated with increased risks for Parkinson's disease (PD). We examined whether hair color, one of the most important phenotypes of pigmentation and a risk factor for melanoma, was associated with PD risk in the Health Professionals Follow-up Study (HPFS; 1986,2002) and the Nurses' Health Study (NHS; 1980,2002). Methods We included 38,641 men and 93,661 women who were free of PD at baseline. Information on natural hair color in early adulthood (age 18,21 years) was assessed via a questionnaire. We also conducted a case,control study (298 PD cases) nested in these two cohorts to examine the association between the melanocortin1-receptor Arg151Cys polymorphism and PD risk. Relative risks (RRs) were estimated using Cox proportional hazards models in the cohort analyses and conditional logistic regression in the nested case,control study. Results PD risk increased with decreasing darkness of hair color. Pooled RRs for PD were 1 (reference), 1.40, 1.61, and 1.93 (95% confidence interval, 1.1,3.4) for black, brown, blond, and red hair, respectively, after adjusting for age, smoking, ethnicity, and other covariates. The associations between hair color and PD were particularly strong for relative younger onset of PD (<70 yr) (adjusted RR for red vs black hair = 3.83; 95% confidence interval, 1.7,8.7). In the case,control study, participants with Cys/Cys genotype, which was associated with red hair, had a greater PD risk, relative to the Arg/Arg genotype (adjusted RR, 3.15; 95% confidence interval, 1.1,9.4). Interpretation These findings suggest a potential role of pigmentation in PD. Ann Neurol 2009;65:76,82 [source] REVIEW: ,-Secretase Inhibitors for the Treatment of Alzheimer's Disease: The Current StateCNS: NEUROSCIENCE AND THERAPEUTICS, Issue 5 2010Francesco Panza SUMMARY Aims: Drugs currently used for the treatment of Alzheimer's disease (AD) partially stabilize patients' symptoms without modifying disease progression. Brain accumulation of oligomeric species of ,-amyloid (A,) peptides, the principal components of senile plaques, is believed to play a crucial role in the development of AD. Based on this hypothesis, huge efforts are being spent to identify drugs able to interfere with proteases regulating A, formation from amyloid precursor protein (APP). This article briefly reviews the profile of ,-secretase inhibitors, compounds that inhibit ,-secretase, the pivotal enzyme that generates A,, and that have reached the clinic. Discussion: Several classes of potent ,-secretase inhibitors have been designed and synthesized. Preclinical studies have indicated that these compounds are able to lower brain A, concentrations and, in some cases, reduce A, plaque deposition in transgenic mouse models of AD. The most developmentally advanced of these compounds is semagacestat, presently in Phase III clinical trials. In animals, semagacestat reduced A, levels in the plasma, cerebrospinal fluid (CSF), and the brain. However, studies have not reported on its cognitive effects. Studies in both healthy volunteers and patients with AD have demonstrated a dose-dependent inhibition of plasma A, levels, and a recent study in healthy subjects demonstrated a robust, dose-dependent inhibition of newly generated A, in the CSF after single oral doses. Conclusions: Unfortunately, ,-secretase inhibitors may cause intestinal goblet cell hyperplasia, thymus atrophy, decrease in lymphocytes, and alterations in hair color, effects associated with the inhibition of the cleavage of Notch, a protein involved in cell development and differentiation. Nevertheless, at least other two promising ,-secretase inhibitors are being tested clinically. This class of drugs represents a major hope to slow the rate of decline of AD. [source] How well do advertising images of health and beauty travel across cultures?PSYCHOLOGY & MARKETING, Issue 10 2006A self-concept perspective This study is a cross-cultural examination of the ideal self-image of women in terms of health and beauty. The match-up between two advertising beauty types (possible advertising presenters) and female consumers' ideal health and beauty images in terms of wanting to look like a specific model were tested with 750 female respondents from five European cities. The respondents also identified the ideal eye and hair colors for health and beauty. This quantitative study revealed cross-cultural variation in ideal self-image in terms of healthy and beautiful beauty types. International advertisers need to understand the important, contemporary, cultural characteristics of an ideal beauty type in terms of healthy or beautiful before developing standardized advertising communicating such appeals. © 2006 Wiley Periodicals, Inc. [source] | ||||||||||