Assessment of Natural Sunlight Protection Provided by 10 High-SPF Broad-Spectrum Sunscreens and Sun-Protective Fabrics.

In 1978, the FDA Advisory Panel proposed both indoor and natural sunlight SPF testing methods but reverted to indoor testing only in 1993. Today's sunscreen sun protection and broad-spectrum claims are based on mandated clinical tests using solar simulators and in vitro spectrophotometers. This research evaluated the protection of 10 high-SPF (30-110), broad-spectrum sunscreen products, as well as 6 sun-protective fabrics against natural sunlight in Arequipa, Peru. Each of the 17 subjects was exposed to natural sunlight for 1 h and 59 min under clear skies, with temperatures and humidity similar to those in an indoor clinical laboratory. Test sites were photographed 16-24 h later. Four dermatologists evaluated the photographs for erythema and persistent pigment darkening (PPD). Perceptible sun-induced skin injury (sunburn and/or pigmentation) was detected at 97% of the sunscreen-protected scores. The most sun-sensitive subjects obtained the least erythema protection. The higher the SPF was, the higher the erythema protection, but the intensity of PPD was also higher. The 2 sunscreens using only FDA-approved sunscreen filters rated 30 SPF and 45+ SPF performed poorly: Eighty-one percent of the 136 scores were graded 1 minimal erythema dose or higher erythema, achieving, at a maximum, SPF of 5-7 in natural sunlight. Sun-protective fabrics tested provided excellent sun protection. The erythema and PPD observed through the sunscreens in less than 2 h are incongruous with the broad-spectrum, high-SPF sunscreen claims. Reapplying these sunscreens and staying in the sun longer, as stated on the product labels, would have subjected the subjects to even more UV exposure. High-SPF, broad-spectrum sunscreen claims based on indoor solar simulator testing do not agree with the natural sunlight protection test results.

Reducing hyperpigmentation after sclerotherapy: A randomized clinical trial.

OBJECTIVE: Sclerotherapy for the treatment of varicose veins is one of the most common medical procedures performed in the Western world, and hyperpigmentation is one of the most frequent, dreaded, minor adverse events. There has recently been some interest in investigating the inflammatory response of the local endothelium after sclerotherapy and the possible benefits of venoactive drugs because of their pleiotropic properties. The aim of this study was to evaluate whether adding a venoactive drug (sulodexide) to the standard sclerotherapy treatment protocol for patients with varicose veins can reduce the occurrence of postsclerotherapy hyperpigmentation. METHODS: We carried out a prospective, multicenter, randomized controlled trial with a parallel group design. It included 720 patients with telangiectasia, reticular veins, or varicose veins who were candidates for sclerotherapy. Patients with reflux in deep system or saphenous veins were excluded. Group A consisted of 354 patients who received an oral dose of sulodexide twice a day for 7 days before scheduled sclerotherapy; the treatment then continued for 3 months. Group B consisted of 366 patients who received the standard sclerotherapy protocol. Polidocanol was used as the sclerosing agent, and 20 to 30 mm Hg compression stockings were used in both groups for 7 days. Control photographs were taken, and a follow-up examination took place after 1 month and 3 months. Computer software was used to analyze the treated area for incidence of hyperpigmentation, total area of hyperpigmentation, skin tone increase in the hyperpigmented area, vein disappearance, and incidence of major bleeding. The sample size was calculated to give a statistical power of 80%. Student t-test and the χ2 test were used for comparative analyses, as appropriate. The level of significance was set at P < .05. RESULTS: A total of 609 patients completed the 3-month follow-up: 312 in group A and 297 in group B. After 1 month, the incidence of hyperpigmentation was 8.7% in group A and 14.8% in group B (P = .01). Group A developed an average area of hyperpigmentation of 10.7% compared with 18.2% in group B (P = .01), and the skin tone of the hyperpigmented area was lower in group A than in group B (P = .02). However, the latter difference was not significant after 3 months. The overall vein disappearance rate was similar in both groups. CONCLUSIONS: Our analysis shows that by adding a venoactive drug (sulodexide) to the standard sclerotherapy protocol, the occurrence of hyperpigmentation is reduced without affecting the desired therapeutic vein elimination response.

Profile of depigmenting cosmetics and dermatological products on the market

The skin is the largest and most exposed organ of the human body, therefore subject to diseases and alteration of its appearance. Among these alterations, the cutaneous hyperchromia may be cited. Currently, the market offers numerous products with depigmenting action to the treatment of such disorders. The aim of this work was to analyze depigmenting products commercialized in establishments in the city of Bento Gonçalves (RS, Brazil) and websites of cosmetic companies. It was found 45 products with depigmenting action and, from these, 59 different active agents were identified. The main active compounds found were kojic acid, arbutin, ascorbic acid, hydroquinone and glycolic acid. Another observed data was that in 78% of the studied products the active substances were being used in combination. The most used vehicles were also studied as a reference to the use of sunscreen in the treatment of cutaneous hyperchromia. The present work had identified in the market a variety of products with depigmentation action and, because of this, it aims to serve as a reference to the healthcare professionals, especially at the prescribing moment, looking for the best results, with regards to treatment efficiency and safety.(AU)

Whitening effects of cosmetic formulation in the vascular component of skin pigmentation.

BACKGROUND: Melanin plays an important role in protecting the skin against the harmful effects of solar radiation, but its abnormal accumulation may become an aesthetic problem, such as melasma and age spots. AIMS: The aim of this study was to evaluate the antiangiogenic and whitening effects of a depigmentation formulation (BLTX) using an in vitro model of human cell and skin culture. METHODS: Human fibroblasts, keratinocytes or melanocytes were treated with BLTX and subjected to oxidative stress by UV radiation or inflammatory stress with IL-1α for quantification of melanin, tyrosinase, endothelin-1, PAR-2, VEGF and iNOS. Fragments of human skin, from elective plastic surgery, were treated with BLTX and subjected to histological evaluation with hematoxylin/eosin associated with Fontana-Masson technique for melanin view. A parametric method, the one-way analysis of variance (ANOVA) followed by the Bonferroni test, was used to compare data among all groups. RESULTS: The results demonstrated that BLTX promotes a reduction in VEGF and iNOS protein synthesis in cultured dermal fibroblasts, indicating an antiangiogenic property. In relation to whitening effect, BLTX was able to reduce the production of melanin in both systems, melanocytes and human skin cultures. The depigmenting action was also revealed by decreasing the levels of endothelin-1, PAR-2 and activity of tyrosinase, when compared to cultures exposed to UV radiation. CONCLUSION: The results allow us to infer that BLTX presents an antiangiogenic effect indicating a role in the vascular component of melasma. Furthermore, the whitening property observed reinforces its use in the prevention and treatment of melasma.

Azelaic acid-loaded nanoemulsion with hyaluronic acid - a new strategy to treat hyperpigmentary skin disorders.

OBJECTIVE: To develop an azelaic acid (AzA)-loaded nanoemulsion with hyaluronic acid (HA) as a double targeting strategy to increase drug retention and tyrosinase inhibition activity. SIGNIFICANCE: Dermic melasma is a recalcitrant disease. Therefore, the development of new technologies that allow a deeper penetration in the skin while enhancing the efficacy of a safe and well-known dermatological active, like AzA, is a very promising alternative to improve the treatment of this disease. METHODS: An oil-in-water nanoemulsion was developed and characterized according to its droplet size distribution, zeta potential, pH value, drug content, encapsulation efficiency, spectroscopic characteristics, morphology, and stability. In vitro mushroom tyrosinase inhibition assay, cytotoxicity, and permeation studies were performed. A descriptive sensory evaluation was also carried out. RESULTS: Drug content was 10 mg/ml, particle size 419 ± 23 nm with monomodal distribution, encapsulation efficiency was 84.65%, zeta potential -10.9 ± 0.44 mV and pH 5.01 ± 0.01. The nanoemulsion was stable for 30 days (30 °C/65% RH). The nanoemulsion decreased tyrosinase activity and permeated through the skin, reaching viable epidermis and dermis and did not show signs of cytotoxicity. Sensory evaluation profile showed a higher spreadability with lesser whitening residue. CONCLUSION: The nanoemulsion presented characteristics within the nanoscale and reached the deeper layers of the skin while improving in vitro tyrosinase inhibition; hence, it could be a promising treatment to dermic melasma.

Biomarkers at different levels of organisation after atrazine formulation (SIPTRAN 500SC®) exposure in Rhinella schineideri (Anura: Bufonidae) Neotropical tadpoles.

Brazil is an important consumer of herbicides. In sugarcane cultivation-the country's most extensive agricultural crop-atrazine-based formulations are the principal form of weed control. Several studies have investigated adverse effects of atrazine or their formulations on anurans, but not specifically on Brazilian species. Our aim was therefore to investigate the lethal and sublethal effects of an atrazine-based herbicide in Rhinella schneideri tadpoles and, in particular, effects on the pigmentation system as a new endpoint in ecotoxicological studies. Rhinella schneideri tadpoles at the Gosner-30 stage were exposed to the atrazine-based herbicide formulation, SIPTRAN 500 SC®, in acute bioassays at concentrations of 1.5-25 mg/L. The lethal and sublethal effects induced were analysed at different ecotoxicological levels: organismal level (alterations in behaviour, growth, development, and body mass; morphologic abnormalities), histological level (liver histopathology), the pigmentation system (melanomacrophages and dermal-melanophores), and cellular level (erythrocyte micronucleus formation and other nuclear-abnormalities). This herbicide induced sublethal effects at the organismal level with alterations in swimming and growth and morphologic abnormalities. These results demonstrated that, in anuran tadpoles, the atrazine-based agrochemical increased the frequency of micronucleus formation and other nuclear-abnormalities in erythrocytes and caused liver damage. In addition, we demonstrated for the first time effects of an atrazine-based formulation on the pigmentation system of anuran tadpoles, specifically an increase in the number of melanomacrophages and dermal melanophores. This study is the first to use several widely differing endpoints at different ecotoxicological levels in a comprehensive manner for assessment of the effects of environmental stressors in order to determine the health status of Neotropical anuran species. In doing so, this study establishes a foundation for future ecological assessments.

Homeostasis in Topical Photoprotection: Getting the Spectral Balance Right.

The solar radiation range has harmful and beneficial effects. Sunscreens, which selectively block specific spectral regions, may potentially interfere with skin homeostasis. For instance, the ultraviolet (UV) B waveband produces erythema and DNA damage; simultaneously, it induces pre-vitamin D3 synthesis. UVA1 and visible light can both induce pigmentation in skin phototypes IV-VI, and act in synergy to induce erythema and persistent pigment darkening. In contrast, UVA may contribute to blood pressure control and cardioprotection by inducing release of nitric oxide from intracutaneous photolabile nitric oxide derivatives. Finally, infrared A radiation alters the collagen equilibrium of the dermal extracellular matrix but is involved in the regulation of body temperature and in nitric oxide release, with a potential beneficial impact on blood pressure regulation. Ideally, photoprotection should thus be performed with a neutral density filter, mitigating all radiation ranges homogeneously, to maintain solar spectrum homeostasis. Natural compounds such as mycosporine-like amino acids are promising natural UV radiation-filtering compounds for an improved homeostasis with our environment. Lastly, we should not forget individual characteristics and behavior, as homeostasis differs according to individual phototypes and skin exposure behaviors.

Behavior and histopathology as biomarkers for evaluation of the effects of paracetamol and propranolol in the neotropical fish species Phalloceros harpagos.

Pharmaceutical drugs in the aquatic environment can induce adverse effects on nontarget organisms. This study aimed to assess the short-term effects of sublethal concentrations of both paracetamol and propranolol on the fish Phalloceros harpagos, specifically light/dark preference, swimming patterns, skin pigmentation, histopathology, and liver glycogen levels. Fish were acutely exposed to sublethal concentrations of both paracetamol (0.008, 0.08, 0.8, 8, 80 mg L-1) and propranolol (0.0001, 0.001, 0.01, 0.1, 1 mg L-1) under controlled conditions. For scototaxis, a significant preference for the dark compartment was observed for the group exposed to the highest concentration of paracetamol (80 mg L-1). Propranolol exposure significantly altered the swimming pattern, especially in fish exposed to the 0.001 mg L-1 concentration. Pigmentation was reduced in propranolol-exposed fish (0.1, 1 mg L-1). The lowest concentration of propranolol (0.0001 mg L-1) induced a decrease of histochemical reaction for hepatic glycogen. These data demonstrate that pharmaceuticals can induce sublethal effects in nontarget organisms, even at low concentrations, compromising specific functions of the individual with ecological relevance, such as energy balance and behavior.

Influence of visible light on cutaneous hyperchromias: Clinical efficacy of broad-spectrum sunscreens.

INTRODUCTION: Cutaneous hyperchromias are disorders of skin pigmentation involving increased melanin production and its irregular accumulation in skin cells. The use of sunscreens is fundamental for the control of hyperchromias by reducing the stimulation of pigmentation, as melanin synthesis is mainly stimulated by solar radiation. Many studies have demonstrated that visible light can induce significant skin damage. Considering the effects of visible light, effective photoprotection should not be limited only to UV protection but should also involve visible and infrared protection. OBJECTIVE: The aim of this study was to evaluate the efficacy of UV-VIS sunscreens in protecting skin against damages caused by solar radiation and the influence of visible light on the appearance of cutaneous hyperchromias. METHODS: Forty volunteers aged 18 to 39 years with skin hyperpigmentation participated in the study. To evaluate the efficacy of the formulations developed, the percentage of hyperpigmented area was evaluated using high-resolution images-Visioface® Quick (Courage-Khazaka, Germany) and the analysis of epidermal pigmentation was performed by RCM-Vivascope® 1500 (Lucid, USA). Also, the melanin index was determined using the Mexameter® M X16 colorimeter (Courage-Khazaka, Germany). RESULTS: The developed formulations were effective in the reduction in melanin index, epidermal pigmentation, and percentage of hyperpigmented area. CONCLUSION: Finally, this study discusses how the combination of UV filters and pigments can protect the skin from solar radiation and reduces skin hyperpigmentations.

New approach in the treatment of refractory vitiligo: CO2 laser combined with betamethasone and salicylic acid solution.

The aim of this study is to evaluate the use of fractional carbon dioxide laser (CO2 ) with betamethasone and salicylic acid solution in the treatment of patients with refractory vitiligo in hands. Each hand of the patient was randomly assigned to one of two groups: lesion treated with fractional carbon dioxide laser associated with betamethasone and salicylic acid solution administration or lesion treated only with betamethasone and salicylic acid solution. We conclude that combined treatment with fractional carbon dioxide laser and betamethasone associated with salicylic acid solution could effectively and safely be used in the treatment of refractory vitiligo.

Effectiveness and safety of topical tacrolimus monotherapy for repigmentation in vitiligo: a comprehensive literature review.

Thus far, several small studies and case reports on the use of topical immunomodulators in vitiligo have been published. We undertook a comprehensive literature review, searching for studies evaluating clinical response to tacrolimus topical therapy for vitiligo. A search was performed on PubMed/Medline using the term "vitiligo", combined with "topical" and "ointment". Our inclusion criteria were: use of tacrolimus ointment as monotherapy to treat vitiligo. We found 29 studies from 2002 to 2014. Overall, 709 patients were treated in 29 studies. Pooling the lesions, 50% repigmentation of vitiligo patches was never achieved before 2 months of treatment, with a peak after 6 months of therapy. The best results were obtained on lesions of the cephalic region, especially the face, with tacrolimus 0.1% ointment two times daily. The percentage of non-responsive patients ranged from 0% to 14%. Treatment was generally well-tolerated; only localized adverse effects were reported. Our objective was to verify the effectiveness and safety of tacrolimus ointment monotherapy. It has good efficacy and tolerability. At present, only small trials and case series are available in the literature. Further, standardized investigations on a larger number of patients are needed.

Effectiveness and safety of topical tacrolimus monotherapy for repigmentation in vitiligo: a comprehensive literature review

Abstract Thus far, several small studies and case reports on the use of topical immunomodulators in vitiligo have been published. We undertook a comprehensive literature review, searching for studies evaluating clinical response to tacrolimus topical therapy for vitiligo. A search was performed on PubMed/Medline using the term “vitiligo”, combined with “topical” and “ointment”. Our inclusion criteria were: use of tacrolimus ointment as monotherapy to treat vitiligo. We found 29 studies from 2002 to 2014. Overall, 709 patients were treated in 29 studies. Pooling the lesions, 50% repigmentation of vitiligo patches was never achieved before 2 months of treatment, with a peak after 6 months of therapy. The best results were obtained on lesions of the cephalic region, especially the face, with tacrolimus 0.1% ointment two times daily. The percentage of non-responsive patients ranged from 0% to 14%. Treatment was generally well-tolerated; only localized adverse effects were reported. Our objective was to verify the effectiveness and safety of tacrolimus ointment monotherapy. It has good efficacy and tolerability. At present, only small trials and case series are available in the literature. Further, standardized investigations on a larger number of patients are needed.

Action of topical mometasone on the pigmented halos of micrografting in patients with vitiligo.

BACKGROUND: Vitiligo is a prevalent skin pigmentation disorder worldwide. The treatments available still offer limited results to some patients. For patients with clinically stable vitiligo, melanocyte transplantation is an appropriate treatment option, and the technique of autologous punch grafting shows good repigmentation. OBJECTIVE: To evaluate the effect of topical mometasone on the halos of repigmentation after autologous punch grafting in patients with clinically stable vitiligo. METHODS: Between 2009 and 2010, 11 patients with clinically stable vitiligo (7 generalized, 2 focal and 2 segmental) underwent autologous punch grafting in the achromic patches. According to the clinical type of vitiligo, patients were instructed to use the corticosteroid ointment during 6 months, only on a few grafted lesions. In the first month, the mometasone ointment was used twice a day and after that just once. They were reassessed 1, 3 and 6 months after the procedure. Grafted halos were photographed and recorded using the software fotofinder. After 6 months, all the treated and untreated areas of the repigmentation halos were measured and analyzed comparatively. RESULTS: The median area of the repigmentation halos after 6 months of treatment with mometasone was larger (25,96 mm(2)) than the one of the untreated halos (13,86 mm(2)), showing a statistically significant difference (p = 0,026). CONCLUSION: In this study, the use of mometasone ointment increased the area of the repigmentation halos after punch grafting. However, this should be further investigated in larger samples in order to validate this positive action in the treatment of stable vitiligo.

Action of topical mometasone on the pigmented halos of micrografting in patients with vitiligo / Ação da mometasona tópica nos halos pigmentares de microenxertia em vitiligo

BACKGROUND: Vitiligo is a prevalent skin pigmentation disorder worldwide. The treatments available still offer limited results to some patients. For patients with clinically stable vitiligo, melanocyte transplantation is an appropriate treatment option, and the technique of autologous punch grafting shows good repigmentation. OBJECTIVE: To evaluate the effect of topical mometasone on the halos of repigmentation after autologous punch grafting in patients with clinically stable vitiligo. METHODS: Between 2009 and 2010, 11 patients with clinically stable vitiligo (7 generalized, 2 focal and 2 segmental) underwent autologous punch grafting in the achromic patches. According to the clinical type of vitiligo, patients were instructed to use the corticosteroid ointment during 6 months, only on a few grafted lesions. In the first month, the mometasone ointment was used twice a day and after that just once. They were reassessed 1, 3 and 6 months after the procedure. Grafted halos were photographed and recorded using the software fotofinder. After 6 months, all the treated and untreated areas of the repigmentation halos were measured and analyzed comparatively. RESULTS: The median area of the repigmentation halos after 6 months of treatment with mometasone was larger (25,96 mm² ) than the one of the untreated halos (13,86 mm² ), showing a statistically significant difference (p = 0,026). CONCLUSION: In this study, the use of mometasone ointment increased the area of the repigmentation halos after punch grafting. However, this should be further investigated in larger samples in order to validate this positive action in the treatment of stable vitiligo.

FUNDAMENTOS: Vitiligo é um transtorno de pigmentação freqüente na população mundial. Seu tratamento ainda oferece resultados limitados em alguns pacientes. Nos casos de vitiligo estável clinicamente, o transplante de melanócitos tornase uma opção terapêutica, sendo a técnica de enxertos autólogos por punch empregada com boa resposta na repigmentação. OBJETIVOS: Estudar a ação do corticoesteróide tópico mometasona sobre halos de repigmentação após enxertos autólogos por punch em pacientes com vitiligo estável clinicamente. MÉTODOS: Entre 2009 e 2010, 11 pacientes com vitiligo estável (7 do tipo generalizado, 2 focal e 2 segmentar) foram submetidos a enxertos autólogos por punch nas máculas acrômicas. Conforme o tipo clínico do vitiligo, os pacientes eram orientados a aplicar pomada de mometasona por 6 meses em lesões enxertadas selecionadas individualmente. No primeiro mês, a aplicação era 2 vezes ao dia e nos demais, apenas uma vez ao dia. Eram reavaliados nos meses 1, 3 e 6 após enxertos cujos halos eram fotografados e registrados pelo software fotofinder. No fim do 6̊mês, todas as áreas dos halos de repigmentação com e sem mometasona foram mensuradas e analisadas comparativamente. RESULTADOS: A mediana da área dos halos de repigmentação após os 6 meses com mometasona foi superior (25,96 mm² ) comparada àquela sem mometasona (13,86 mm² ), com diferença estatisticamente significante (p=0,026). CONCLUSÃO: Em nossa casuística, o uso da mometasona tópica determinou incremento dos halos de repigmentação após enxertia. A amplificação da amostra se faz necessária em estudos posteriores a fim de ratificar esta ação positiva da mometasona no tratamento do vitiligo estável.

Safety and effectiveness of hyaluronic acid fillers in skin of color.

OBJECTIVES: To assess the safety and effectiveness of hyaluronic acid (HA) fillers in skin of color. METHODS: Two prospective studies followed up subjects with Fitzpatrick skin phototypes of IV, V, or VI for 24 weeks after dermal filler injections. In a double-blind, randomized study, subjects were injected with one of three high concentration (24 mg/mL) HA fillers (Juvéderm Ultra, Ultra Plus, and 30) in one nasolabial fold and Zyplast collagen in the other. In an open-label, randomized study, subjects received one of three low concentration (5.5 mg/mL) HA fillers (Hylaform, Hylaform Plus, and Captique) in both nasolabial folds. RESULTS: A total of 160 subjects (a subset of 439 study subjects) were randomized and treated with one of the three high concentration fillers, and 119 subjects were randomized and treated with one of the three low concentration fillers. For subjects treated with the high concentration fillers there were no occurrences of hypersensitivity or hypertrophic scarring, and no increased incidence of hyperpigmentation or hypopigmentation in non-Caucasian vs. Caucasian subjects. For subjects treated with the low concentration fillers there were no occurrences of keloid formation, hypertrophic scarring, hypopigmentation, hypersensitivity, and three instances of mild hyperpigmentation. For all of the fillers the majority of subjects maintained >/=1 point improvement in nasolabial fold severity scores through 24 weeks. CONCLUSIONS: All of the HA fillers were well tolerated in individuals with skin of color and demonstrated effectiveness throughout the 24 week period. Furthermore, the fillers provided smooth, natural-looking wrinkle correction in darker skin types.

[Evaluation of an antioxidant and mitochondria-stimulating cream formula on the skin of patients with stable common vitiligo]. / Evaluación de una formulación antioxidante y estimuladora mitocondrial en piel de pacientes con vitiligo vulgar estable.

Vitiligo is a chronic illness of a yet unknown etiology, characterized by an acquired and progressive depigmentation of the skin. There are diverse treatments for this condition around the world, but up to now, none has been completely effective. The objective of this work was to evaluate the application of an antioxidant and mitochondrial stimulating formula, of topic use in leukodermic areas of patients with stable vulgar vitiligo. A clinical, experimental, randomized, double blind study was carried out in 50 male and 50 female patients with stable vulgar vitiligo. The patients were distributed in five groups as follows: Group 1 (labelled as VitilVenz AF): application of antioxidant and mitochondrial stimulating cream and oral administration of antioxidants and phenylalanine. Group 2 (labelled as Placebo AF): application of a placebo cream and oral administration of antioxidants and phenylalanine. Group 3 (labelled as without cream AF): oral administration of antioxidants and phenylalanine. Group 4 (labelled as Placebo cream): application of a placebo cream. Group 5 (labelled as VitilVenz): application of the antioxidant and mitochondrial stimulating cream. The following were measured in all patients: the clinical area of newly formed pigment every 30 days, during five months; and the presence of melanocytes in the histological study, at the beginning and at the end of treatment. The test of multiple comparison of Turkey-Kramer was used for the analysis of the results. The scheme of treatment that produced the best results was that of the Group 1, which consisted of the joint application of the antioxidant and mitochondrial stimulating cream and oral administration of antioxidants and phenylalanine (p < 0.001); followed by Group 5 that only received the topical treatment with the antioxidant and mitochondrial stimulating cream. The clinical and histological responses of these two groups (1 and 5) were significantly different to the rest of the groups. We concluded that the melanocytes in these patients could be in a dysfunctional state, product of the formation of free radicals that cause cellular and mitochondrial toxicity; and that these free radicals are removed by the antioxidant and mitochondrial stimulating elements present in the cream, turning the melanocytes functional and producing melanin in the achromic area of the vitiligo. This effect would be potentiated by the use of oral antioxidants and phenylalanine.

Countergradient variation in the sexual coloration of guppies (Poecilia reticulata): drosopterin synthesis balances carotenoid availability.

Trinidad guppies (Poecilia reticulata) are distributed along an environmental gradient in carotenoid availability that limits the carotenoid content of the orange spots of males. The amount of synthetic red pteridines (drosopterins) in the orange spots covaries with the carotenoid content, such that the ratio of the two types of pigments is roughly conserved across streams. Carotenoids and drosopterins have different spectral properties and thus the ratio of the two types of pigments affects the shape of the orange spot reflectance spectrum. Geographic conservation of the carotenoid:drosopterin ratio suggests that males may be under selection to maintain a particular hue. We tested this hypothesis by comparing the pigmentation and coloration of guppies from six streams in the field to that of second-generation descendants of the same populations raised on three dietary carotenoid levels in the laboratory. The results show clearly that the geographic variation in drosopterin production is largely genetic and that the hue of the orange spots is conserved among populations in the field, relative to the laboratory diet groups. This is a countergradient pattern because genetic differences between populations in drosopterin production mask the effect of carotenoid availability on the hue of the orange spots. The potential for countergradient sexual selection to contribute to reproductive isolation between populations is discussed.

Depigmentation and rejuvenation effects of kinetin on the aged skin of hairless descendants of Mexican hairless dogs.

The depigmenting and anti-aging effects of kinetin (KN) solutions on the aged skin of hairless dogs were clinically and histologically investigated. Grossly, all KN-treated sites became mildly depigmented. At 50 days of topical treatment with KN solutions, apparent improvement was observed in the skin texture, wrinkling, and pigmentation. At 100 days of KN treatment, both the skin rejuvenation and depigmentation effects became more prominent. Throughout the experimental period of KN treatment, no adverse effects were found in any sites treated with KN solutions. In the colorimetric system, at 100 days of topical treatment with KN solutions, the L* and b* values in the sites treated with KN solutions significantly increased. Histologically, at 50 days of topical treatment with KN solutions, the KN-treated sites showed a decrease in the thickness of the corneal layers. Melanin granules decreased throughout all epidermal layers. In the dermis, the large number of fine collagen and elastic fibers were densely aligned. At the end of the treatment, this agent was equally effective against pigmented lesions irrespective of the concentration of KN solution. The distribution of melanin granules returned to normal in the skin of adult hairless dogs. Throughout the present study, there were no histologic abnormalities in the epidermis and the dermis. These results revealed that topical treatment with lower concentrations of KN solutions normalized hyperpigmentation and improved the aged skin structure of hairless dogs. In addition, it was clarified that KN solutions had no adverse effects on the skin of hairless dogs and that this agent was a safe chemical for long-term application.

The effect of acidified soapstocks on feed conversion and broiler skin pigmentation.

The effect of different soapstocks (corn, sunflower, canola, and soybean) on productive performance and skin broiler pigmentation was investigated. Soapstock was added to reach 1.0% polyunsaturated fatty acids in the diet. The addition of soybean soapstock significantly improved live body weight gain of the birds from 1 to 7 wk of age. A live body weight gain of 1,736 g/bird was calculated for broilers fed with the soybean soapstock diet. Feed conversion was significantly higher for broilers fed with the soybean soapstock diet, and no negative effect was observed. Compared to broilers fed with Pixtafil (100.0% pigmentation), those fed soybean soapstock (when added as a supplement of 1.0% polyunsaturated fatty acids in the diet) reached 48.0% pigmentation, and those fed corn soapstock reached only 7.3%. When the diets were complemented with Pixtafil to reach 100% of calculated pigmentation, the soybean soapstock diet reached 100.8% pigmentation compared to a canola soapstock diet that reached 72.0% pigmentation. Acidified soybean soapstock could be a source of polyunsaturated fatty acids and of xantophyl pigments in broiler feeding.

Comparative EPR and fluorescence conformational studies of fully active spin-labeled melanotropic peptides.

Similar to melanocyte stimulating hormone (alpha-MSH), its potent and long-acting analogue, [Nle(4), D-Phe(7)]alpha-MSH, when labeled with the paramagnetic amino acid probe 2,2,6,6-tetramethylpiperidine-N-oxyl-4-amino-4-carboxylic acid (Toac), maintains its full biological potency, thus validating any comparative structural investigations between the two labeled peptides. Correlation times, calculated from the electron paramagnetic resonance signal of Toac bound to the peptides, and Toac-Trp distances, estimated from the Toac fluorescence quenching of the Trp residue present in the peptides, indicate a more rigid and folded structure for the potent analogue as compared to the hormone, in aqueous medium.