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1.
Exp Dermatol ; 28(11): 1252-1257, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31446631

RESUMO

We developed an artificial intelligence algorithm (AIA) for smartphones to determine the severity of facial acne using the GEA scale and to identify different types of acne lesion (comedonal, inflammatory) and postinflammatory hyperpigmentation (PIHP) or residual hyperpigmentation. Overall, 5972 images (face, right and left profiles) obtained with smartphones (IOS and/or Android) from 1072 acne patients were collected. Three trained dermatologists assessed the acne severity for each patient. One acne severity grade per patient (grade given by the majority of the three dermatologists from the two sets of three images) was used to train the algorithm. Acne lesion identification was performed from a subgroup of 348 images using a tagging tool; tagged images served to train the algorithm. The algorithm evolved and was adjusted for sensibility, specificity and correlation using new images. The correlation between the GEA grade and the quantification and qualification of acne lesions both by the AIA and the experts for each image were evaluated for all AIA versions. At final version 6, the GEA grading provided by AIA reached 68% and was similar to that provided by the dermatologists. Between version 4 and version 6, AIA improved precision results multiplied by 1.5 for inflammatory lesions, 2.5 for non-inflammatory lesions and by 2 for PIHP; recall was improved by 2.6, 1.6 and 2.7. The weighted average of precision and recall or F1 score was 84% for inflammatory lesions, 61% for non-inflammatory lesions and 72% for PIHP.


Assuntos
Acne Vulgar/diagnóstico , Inteligência Artificial , Índice de Gravidade de Doença , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis , Smartphone , Adulto Jovem
2.
Photodermatol Photoimmunol Photomed ; 35(6): 387-392, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31206816

RESUMO

The pigment responses of human skin to broadband UVA radiation (320-400 nm) occur in three distinct phases. The first phase includes immediate pigment darkening (IPD), the pigment that appears immediately after irradiation. The second phase involves an intermediate step, termed persistent pigment darkening (PPD), which leads to the third phase of neomelanogenesis or delayed tanning (DT). Since DT results from synthesis of new melanin, it persists beyond 5-7 days. We conducted studies on human subjects to investigate the dynamic responses of the IPD and PPD reactions to broadband UVA radiation at threshold and superthreshold doses. The threshold doses for IPD, PPD, and DT were found to be approximately 1, 11, and 18 J/cm2 , respectively. The colorimetry ΔL* value corresponding to minimal clinically perceptible pigmentation was found to be 0.8 ± 0.1. IPD appeared immediately and had an associated decay constant of approximately 1.4 minutes. At doses greater than PPD threshold, IPD reaction decayed while PPD developed indicating toward IPD being used as a substrate in the formation of PPD.


Assuntos
Melaninas/biossíntese , Melaninas/efeitos da radiação , Pigmentação da Pele/efeitos da radiação , Bronzeado/fisiologia , Raios Ultravioleta , Colorimetria , Humanos , Cinética , Fatores de Tempo
3.
Skin Pharmacol Physiol ; 31(2): 107-113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29408821

RESUMO

BACKGROUND/AIMS: There is increasing evidence that exposure to air pollutants, including particulate matter (PM2.5, PM10), nitrogen dioxide (NO2), and sulfur dioxide (SO2), might aggravate preexisting skin diseases such as eczema and urticaria. Here we investigated if a possible link exists between air pollution and acne vulgaris. We assessed the association between ambient air pollutant concentrations and the number of visits of patients for acne vulgaris to a dermatological outpatient clinic in Beijing, China, from April 1, 2012 to April 30, 2014. METHODS: In this time period, 59,325 outpatient visits were recorded because of acne vulgaris. Daily air pollution parameters for PM10, PM2.5, SO2, and NO2 were obtained from the Beijing Municipal Environmental Monitoring Center. RESULTS: Increased concentrations of ambient PM2.5, PM10, and NO2 were significantly associated with increased numbers of outpatient visits for acne vulgaris over the 2 years. These effects could be observed for NO2 in a single-pollutant model and for PM2.5, PM10, and NO2 in 2-pollutant models, which are closer to real-life exposure. Of note, these effects were specific because they were not observed for increased SO2 concentrations, which even showed negative correlations in all test models. CONCLUSION: This study provides indirect evidence for a link between acne vulgaris and air pollution.


Assuntos
Acne Vulgar/patologia , Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Adolescente , Adulto , Pequim , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/efeitos adversos , Pacientes Ambulatoriais , Material Particulado/efeitos adversos , Dióxido de Enxofre/efeitos adversos , Fatores de Tempo , Adulto Jovem
4.
Exp Dermatol ; 26(9): 798-803, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28094874

RESUMO

Propionibacterium acnes (P. acnes), the sebaceous gland and follicular keratinocytes are considered the three actors involved in the development of acne. This exploratory study investigated the characteristics of the skin microbiota in subjects with acne and determined microbiota changes after 28 days of application of erythromycin 4% or a dermocosmetic. Skin microbiota were collected under axenic conditions from comedones, papulo-pustular lesions and non-lesional skin areas from subjects with mild to moderate acne according to the GEA grading using swabs. Samples were characterized using a high-throughput sequencing approach that targets a portion of the bacterial 16S rRNA gene. Overall, microbiota samples from 26 subjects showed an overabundance of Proteobacteria and Firmicutes and an under-representation of Actinobacteria. Staphylococci were more abundant on the surface of comedones, papules and pustules (P=.004 and P=.003 respectively) than on non-lesional skin. Their proportions increased significantly with acne severity (P<.05 between GEA-2 and GEA-3). Propionibacteria represented less than 2% of the bacteria on the skin surface. At Day 28, only the number of Actinobacteria had decreased with erythromycin while the dermocosmetic decreased also the number of Staphylococci. A significant reduction (P<.05) from Day 0 of comedones, papules and pustules with no significant difference between the products was observed. The bacterial diversity on all sampling areas was similar. The dermocosmetic decreased the number of Actinobacteria and Staphylococcus spp. after 28 days. Staphylococcus remained the predominant genus of the superficial skin microbiota. No significant reduction in Staphylococcus spp. was observed with the topical antibiotic.


Assuntos
Acne Vulgar/tratamento farmacológico , Acne Vulgar/microbiologia , Antibacterianos/administração & dosagem , Eritromicina/administração & dosagem , Microbiota/efeitos dos fármacos , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pele/microbiologia , Staphylococcus/isolamento & purificação , Adulto Jovem
5.
Acta Derm Venereol ; 97(10): 1196-1201, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28661544

RESUMO

Patients with photodermatoses or actinic keratosis benefit from very high ultraviolet B-ultraviolet A (UVB-UVA) photoprotection. However, poor compliance is an issue that jeopardizes adequate protection, leading to disease recurrence. This study evaluated the efficacy of a daily protective moisturizer with high UVB and UVA photoprotection applied 8 h before irradiation. A monocentric, open-label, prospective, control pilot study was performed including 10 patients. Patients were irradiated with UVB and UVA before and 8 h after topical application of the product. Reflectance confocal microscopy (RCM) assessment was performed 24 h later. Clinical assessment showed a statistically significant increase in minimal erythema dose (MED) after application of the product (p <0.001). Signs of UV damage according to RCM were not observed on photoprotected skin (p <0.05). Skin irradiated 8 h after applying a daily protective moisturizer presented an increase in MED and RCM findings that equal the findings for non-irradiated skin.


Assuntos
Microscopia Confocal/métodos , Transtornos de Fotossensibilidade/tratamento farmacológico , Creme para a Pele/administração & dosagem , Dermatopatias Genéticas/tratamento farmacológico , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Queimadura Solar/prevenção & controle , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos , Administração Cutânea , Adolescente , Adulto , Esquema de Medicação , Eritema/etiologia , Eritema/patologia , Eritema/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Fotossensibilidade/complicações , Transtornos de Fotossensibilidade/diagnóstico , Projetos Piloto , Estudos Prospectivos , Pele/patologia , Creme para a Pele/efeitos adversos , Dermatopatias Genéticas/complicações , Dermatopatias Genéticas/diagnóstico , Queimadura Solar/etiologia , Queimadura Solar/patologia , Protetores Solares/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
6.
Photochem Photobiol Sci ; 9(4): 516-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354645

RESUMO

The importance of adequate UVA protection is apparent with improved understanding of UVA-induced skin damage. This has led to the development of new sunscreen ingredients. A number of regulatory bodies or experts from the industry and academia have proposed methods to assess the efficacy of sunscreens against UVA radiation. In addition different proposals have been made regarding the labeling for UVA protection. The purpose of this paper is to describe several in vitro methods for measuring UVA protection of sunscreen products and to consider their validity. The different proposals in terms of UVA labeling are also presented and discussed. This review illustrates the need for standardization of the measurement conditions and harmonization to convey to consumers the most appropriate information on UVA protection.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Rotulagem de Medicamentos/métodos , Proteção Radiológica , Raios Ultravioleta/efeitos adversos , Protetores Solares/química , Protetores Solares/farmacologia
7.
J Am Acad Dermatol ; 58(5 Suppl 2): S149-54, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18410801

RESUMO

BACKGROUND: It is well established that ultraviolet (UV) radiation induces immunomodulatory effects that may be involved in skin cancer. Recent studies have shown that UVA (320-400 nm) and UVB (290-320 nm) radiation are immunosuppressive. As a result, sunscreens, which mainly absorb UVB, may be less effective in preventing UV radiation-induced immunosuppression than broad-spectrum products. OBJECTIVE: We sought to study the effects of UVA exposure on human delayed-type hypersensitivity (DTH) response and compare the efficacy of sunscreens having different levels of sun-protection factor (SPF) and UVA protection against both solar-simulated radiation and outdoor real-life sunlight exposure conditions. METHODS: DTH was assessed using a kit which includes 7 recall antigens that most of the participants encountered during childhood immunization. Evaluation of DTH test response was made 48 hours after test application before and after UV exposure with or without sunscreens. RESULTS: In unprotected participants, the response to DTH tests was significantly reduced irrespective of UV types of exposure (full-spectrum UVA, long UVA, solar-simulated radiation). A UVB sunscreen failed to protect from solar-simulated radiation-induced immunosuppression. In contrast, a broad-spectrum sunscreen with the same SPF but providing a high protection in the UVA range significantly reduced local UV-induced immunosuppression and prevented the distant effects. In the outdoor study, as compared with DTH responses obtained before sun exposure, no alteration of immune response was detected when the skin was protected by a broad-spectrum sunscreen having a high protection level in the UVA (SPF 25, UVA protection factor 14). Conversely a broad-spectrum sunscreen with lower protection against UVA (SPF 25, UVA protection factor 6) failed to prevent UV-impaired response. LIMITATIONS: These results have been obtained after repeated exposure. Additional experiments obtained under acute exposure are in progress. CONCLUSION: These findings clearly demonstrated the role of UVA in the induction of photoimmunosuppression together with the need for sunscreen products providing efficient photoprotection throughout the entire UV spectrum.


Assuntos
Hipersensibilidade Tardia/imunologia , Pele/efeitos da radiação , Luz Solar/efeitos adversos , Protetores Solares/uso terapêutico , Raios Ultravioleta/efeitos adversos , Absorção , Adolescente , Adulto , Feminino , Humanos , Hipersensibilidade Tardia/prevenção & controle , Tolerância Imunológica/imunologia , Masculino , Doses de Radiação , Neoplasias Cutâneas/prevenção & controle , Protetores Solares/farmacologia
8.
Photodermatol Photoimmunol Photomed ; 24(4): 164-74, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18717957

RESUMO

BACKGROUND: UVA exposure of human skin mainly produces reactive oxygen species (ROS) leading to DNA, cell and tissue damage. It alters immune function, pigmentation and it is certainly responsible for a large part of photoaging changes. Moreover UVA is implicated in the etiology of several photodermatoses. As a consequence, to provide adequate protection, sunscreens or skin care products for daily use protective products need UVA absorbers combined with UVB ones. AIM: To assess the efficacy of sunscreens containing a broad-spectrum UVA absorber the Mexoryls SX or ecamsule and to compare formulations with and without it through a large number of clinical studies in human volunteers and patients. METHODS: The following assessments were conducted: *Prevention of excessive pigmentation induced by UV exposure in Caucasian and Asian skins using a method that measures pigmentation protection factors (PPF). *Efficacy against DNA damage by measurement of pyrimidine dimer formation and p53 protein accumulation. *Protection of immune system using delayed type hypersensitivity (DTH) reactions to recall antigens, isomerization of urocanic acid (UCA), alteration of Langerhans cells (LC) density, morphology and function. *Reduction of epidermal and dermal alterations induced by repeated UVA or UV solar simulated radiation (SSR) using histology or immunohistology. *Prevention of the polymorphous light eruption (PMLE) in patients prone to develop this disease. RESULTS: Mexoryls SX-containing formulations showed a dose-dependent level of protection against pigmentation. For a same sun protection factor (SPF) the higher the UVA protection was, the higher was the PPF. Pyrimidine dimer formation and p53 accumulation were significantly reduced by formulations with Mexoryls SX. In the studies looking at the suppression of DTH reactions to recall antigens by the different UV spectra, the LC alterations and the cis UCA formation, Mexoryls SX formulations always showed a higher protective potency than sunscreen without it even when the protection against erythema was similar (products with same SPF). Mexoryls SX formulations also prevented or significantly decreased to minimal, ferritin, tenascin and lysozyme expression induced by repeated UVA or SSR exposure. It also reduced the enhancement of collagenase 2 mRNA expression induced by SSR exposure. Finally PMLE study demonstrated that UVA protection was essential for the prevention of this photodermatose. CONCLUSION: Mexoryls SX formulated in sunscreens or daily use products have been shown to be an effective UV absorber, leading to an increased efficacy of these products against a large number of biological damage induced by UVA, SSR or sun exposure.


Assuntos
Canfanos/uso terapêutico , Transtornos de Fotossensibilidade/prevenção & controle , Lesões por Radiação/prevenção & controle , Envelhecimento da Pele , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Ácidos Sulfônicos/uso terapêutico , Protetores Solares/uso terapêutico , Raios Ultravioleta/efeitos adversos , Canfanos/química , Canfanos/farmacologia , Humanos , Hipersensibilidade Tardia/tratamento farmacológico , Hipersensibilidade Tardia/etiologia , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/efeitos da radiação , Dímeros de Pirimidina/metabolismo , Doses de Radiação , Pele/imunologia , Pele/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/patologia , Envelhecimento da Pele/efeitos da radiação , Pigmentação da Pele/efeitos dos fármacos , Pigmentação da Pele/efeitos da radiação , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologia , Protetores Solares/química , Protetores Solares/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta/classificação
9.
Onco Targets Ther ; 11: 5865-5872, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30271169

RESUMO

INTRODUCTION: The purpose of this multicenter, prospective, observational, open-label study was to evaluate the use and tolerability of dermo-cosmetic products in preventing skin reactions associated with cancer treatments. PATIENTS AND METHODS: A 12-product kit was supplied to patients before chemotherapy began and was to be used throughout the treatment phase. Cutaneous adverse events were evaluated at each treatment session. Physicians evaluated skin reactions (edema, erythema, dryness, desquamation, pigmentation disorders, and cracks) and gave their opinion on the skin benefit for patients at the end of the study. Patients also evaluated the product benefit using the Patient Benefit Index (PBI) questionnaire. Results were analyzed by subgroups of casual and regular users, based on number and frequency of products used. RESULTS: A total of 147 patients were enrolled in cancer services in Germany, France, Italy, Spain, and Canada. Mean age was 59 years with 71% being female. Product tolerance on whole body was rated good to excellent for at least 89% of the patients for each product. Aggravated skin reactions during the study were reported more frequently by casual users than regular users (39.5% versus 22%; p=0.029). Similarly, casual users reported more erythema aggravation (p=0.02) and desquamation (p=0.03) than regular users. PBI >1 was reported for 95.5% of patients and regular users had significantly higher scores than casual users (p=0.049). DISCUSSION: Overall, the 12-product kit was very well tolerated, with regular users reporting benefits more frequently than casual users. Results support international recommendations to use appropriate skin care products to minimize the impact of cutaneous reactions associated with chemotherapy.

10.
Breast Cancer (Auckl) ; 12: 1178223417752772, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29434476

RESUMO

PURPOSE: As many as 50% of patients with cancer develop acute skin reactions to some degree with radiotherapy. Proactive skin care is often recommended to minimise these skin reactions and maintain the integrity of the epidermal barrier; nevertheless, no consensual guidelines are systematically used. This multicentre, observational, prospective study evaluated the tolerability and benefit of supportive and barrier protective skin care products in preventing radiotherapy-induced skin reactions in 253 women initiating radiotherapy (exclusive or adjuvant) for breast cancer. METHODS: Patients received a kit of 5 commercially available skin care products before the first radiotherapy treatment. The following variables were assessed: cutaneous adverse events, investigator-assessed skin reactions (oedema, erythema, dryness, desquamation) before and after radiotherapy course, investigator, and patient opinion on products benefit. Results were analysed by frequency of product use (heavy versus low). RESULTS: Average age was 60 years (range: 34-85). Over 92% of patients reported good to excellent tolerance on irradiated skin for each product. During the 6-week radiotherapy period, we observed that heavy product users had less skin reactions than the low users, particularly within 10 days of radiotherapy initiation (8% versus 18%; p = .031). Positive physician's opinion on product use was more frequent for high (66.6%) versus low (32%) users. Patient-assessed patient benefit index was generally >1, indicating relevant treatment benefit, with a tendency for better benefit in high versus low users. CONCLUSIONS: These results support recommendations to use skin care products to minimise the impact of secondary cutaneous reactions with radiotherapy cancer treatment.

11.
PLoS One ; 13(1): e0190233, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29293664

RESUMO

Excessive ultraviolet (UV) radiation induces acute and chronic effects on the skin, eye and immune system. Personalized monitoring of UV radiation is thus paramount to measure the extent of personal sun exposure, which could vary with environment, lifestyle, and sunscreen use. Here, we demonstrate an ultralow modulus, stretchable, skin-mounted UV patch that measures personal UV doses. The patch contains functional layers of ultrathin stretchable electronics and a photosensitive patterned dye that reacts to UV radiation. Color changes in the photosensitive dyes correspond to UV radiation intensity and are analyzed with a smartphone camera. A software application has feature recognition, lighting condition correction, and quantification algorithms that detect and quantify changes in color. These color changes are then correlated with corresponding shifts in UV dose, and compared to existing UV dose risk levels. The soft mechanics of the UV patch allow for multi-day wear in the presence of sunscreen and water. Two evaluation studies serve to demonstrate the utility of the UV patch during daily activities with and without sunscreen application.


Assuntos
Eletrônica , Epiderme/fisiologia , Fotoquímica , Raios Ultravioleta , Algoritmos , Corantes , Humanos
12.
Eur J Dermatol ; 27(2): 144-149, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28251894

RESUMO

To date, facial acne flare-ups in adult women during the luteal phase of the menstrual cycle have been poorly investigated. To clinically characterize premenstrual acne flare-up in adult women and investigate the effect of a dermocosmetic treatment. This single-centre study included 32 young adult women with declared premenstrual acne flares and was composed of two phases: (1) an observational phase (two menstrual cycles) and (2) an interventional phase (one menstrual cycle) in a controlled, randomised, double-blind, intra-individual (half-face) setting in which a dermocosmetic (containing lipohydroxyacid, nicotinamide, and piroctone-olamine) and placebo were compared. Initially, during the first part of the study, we observed that premenstrual acne flare-ups in adult women were characterized by a significant increase in the number of papules (20.2 vs. 13.7; p = 0.0008) and to a lesser extent, closed comedones (25.6 vs. 22.7; p = 0.04). Secondly, during the interventional phase, the half-face treated with the dermocosmetic formulation showed a significantly lower number of inflammatory lesions (7.6 vs 9.4; p = 0.01) during the luteal phase compared to the half-face treated with the placebo. Tolerance of the dermocosmetic formulation was rated as good or excellent. Our data indicate a significant increase in the number of papules during premenstrual acne flare-ups in adult women and the use of a dermocosmetic may be of benefit in partially reducing this premenstrual inflammatory flare-up.


Assuntos
Acne Vulgar/tratamento farmacológico , Cosmecêuticos/uso terapêutico , Etanolaminas/uso terapêutico , Fase Luteal , Niacinamida/uso terapêutico , Piridonas/uso terapêutico , Salicilatos/uso terapêutico , Acne Vulgar/patologia , Adolescente , Adulto , Cosmecêuticos/efeitos adversos , Método Duplo-Cego , Combinação de Medicamentos , Etanolaminas/efeitos adversos , Feminino , Humanos , Niacinamida/efeitos adversos , Piridonas/efeitos adversos , Salicilatos/efeitos adversos , Exacerbação dos Sintomas , Adulto Jovem
13.
Clin Cosmet Investig Dermatol ; 10: 199-204, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28579815

RESUMO

In recent years, the critical role that inflammation may play in the development and progression of acne has become increasingly recognized. The prevalence of acne is similar between Asian and Caucasian women, but Asian women have a higher prevalence of inflammatory acne. They also report their symptoms exacerbate during periods of high air pollution. The objective of this study was to review the current evidence that links air pollution to worsening of acne symptoms. Firstly, a group of five Asian and three European scientists with expertise in Dermatology reviewed the current literature and described current acne treatment practices in their countries. During this activity, they identified the need for further epidemiological and clinical research. Secondly, additional studies ensued which provided evidence that acne symptoms might exacerbate in regions of high ambient air pollution. Based on these findings, the authors suggest that people with acne should protect the natural barrier function of their skin with emollients and ultraviolet (UV)A/UVB protection.

14.
J Invest Dermatol ; 125(3): 403-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16117779

RESUMO

It is increasingly accepted that sunscreens should protect against ultraviolet radiation (UVR)-induced immunosuppression, with an index of protection that can be compared with the sun protection factor (SPF). Five groups of immunoprotection researchers met to discuss the status of immune protection factor (IPF) evaluation in human skin in vivo. Current methods rely on a suncreen's inhibition of UVR-induced local suppression of the contact hypersensitivity (CHS) response or the delayed-type hypersensitivity (DTH) response, using either the induction or the elicitation arms of these responses. The induction arm of the CHS response has the advantage of being sensitive to a single sub-erythemal exposure of solar-simulating radiation (SSR) that allows a direct comparison with the SPF. This approach, which necessitates sensitization, requires a large number of volunteers and is too labor intensive and time consuming to become a routine method. The elicitation arm of the CHS or DTH responses exploits prior sensitization to contact or recall antigens and has the advantage of being possible to apply on small groups of volunteers. Some current protocols, however, require repeat SSR exposures, which invalidates a direct comparison with SPF that is based on a single exposure. There is a need for a new simpler method of IPF that will have to be validated against existing models.


Assuntos
Tolerância Imunológica/efeitos da radiação , Protetores Solares/farmacologia , Dermatite de Contato/imunologia , Humanos , Hipersensibilidade Tardia/imunologia , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/efeitos da radiação , Tolerância Imunológica/efeitos dos fármacos , Fatores Imunológicos/análise , Técnicas Imunológicas , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/prevenção & controle , Luz Solar , Protetores Solares/uso terapêutico , Raios Ultravioleta
15.
Indian J Dermatol Venereol Leprol ; 78 Suppl 1: S24-30, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22710110

RESUMO

Skin exposure to sunlight can cause many adverse effects. It is now recognized that both Ultraviolet A (UVA) and UVB wavelengths are responsible for the detrimental effects of solar radiation on skin. With our increasing knowledge on the harmful effects of UVA, the need for effective, well-balanced photoprotection has become more crucial. Numerous clinical studies showed that well-balanced sunscreen, with a SPF/UVAPF ratio ≤ 3, provide the most effective protection against pigmentation (especially on dark skin), DNA damage, UV-induced skin immunosuppression and photodermatoses. The calculation of UVA protection required in Asia revealed its particular importance in India, and gives clear evidence that the SPF value alone is not sufficient to evaluate the efficacy of a sunscreen.


Assuntos
Transtornos de Fotossensibilidade/prevenção & controle , Pele/efeitos da radiação , Protetores Solares/uso terapêutico , Raios Ultravioleta/efeitos adversos , Ásia , Dano ao DNA/efeitos da radiação , Proteínas de Ligação a DNA/efeitos da radiação , Relação Dose-Resposta a Droga , Humanos , Tolerância Imunológica/efeitos da radiação , Pigmentação da Pele/efeitos da radiação , Luz Solar , Fatores de Tempo
16.
Indian J Dermatol Venereol Leprol ; 78 Suppl 1: S31-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22710111

RESUMO

Skin exposure to acute or repetitive ultraviolet light induces risks which are now well identified. An efficient photoprotection is thus required for both UVB and UVA radiation. In particular, increasing evidence of the detrimental effects of UVA on skin has led to the development of a new generation of sunscreens that provide effective protection throughout the whole UV radiation spectrum. Many new UV filters have been introduced in the last decade, particularly UVA filters, with improved efficacy and safety. Sunscreen filters must be carefully combined to achieve esthetically pleasing products offering photostable and well-balanced photoprotection.


Assuntos
Transtornos de Fotossensibilidade/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Pele/efeitos da radiação , Luz Solar/efeitos adversos , Protetores Solares/uso terapêutico , Raios Ultravioleta/efeitos adversos , Relação Dose-Resposta à Radiação , Humanos , Proteção Radiológica/métodos , Protetores Solares/química , Fatores de Tempo , Raios Ultravioleta/classificação
17.
Photodermatol Photoimmunol Photomed ; 22(3): 124-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16719864

RESUMO

BACKGROUND/PURPOSE: The aims of the present studies were to check that persistent pigment darkening (PPD) method can produce accurate and reproducible results for high UVA protection factors (UVAPF) and to provide data on the variability between laboratories and on the influence of skin types. METHODS: The Japanese Cosmetic Industry Association (JCIA) PPD method was used to determine the UVAPF in different laboratories of different sunscreen formulations with increasing UVAPF. Two formulations were tested at seven independent laboratories and five products within two laboratories. The influence of skin types on the UVAPF of two products was tested within one laboratory on two panels of volunteers. All laboratories complied with the JCIA method specifications. RESULTS: Reproducible results have been obtained between the different labs and a low and satisfactory variability was achieved with a panel size of 10 subjects. Furthermore, skin type was demonstrated to have no influence within the defined selection criteria. CONCLUSIONS: From this multiple center testing, the PPD method has been shown to be appropriate for testing sunscreen formulations with UVAPFs above 20. It is reasonable to expect that test results will be consistent if an identical protocol is used between laboratories.


Assuntos
Pigmentação da Pele/efeitos dos fármacos , Protetores Solares , Raios Ultravioleta , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Projetos de Pesquisa , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Pigmentação da Pele/efeitos da radiação
19.
Photodermatol Photoimmunol Photomed ; 20(5): 243-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15379874

RESUMO

BACKGROUND/PURPOSE: Exposure to ultraviolet (UV) radiation increases skin pigmentation and usually results in an even darkening of the skin. However, it may also occasionally lead to the development of hyperpigmented lesions due to a local overproduction of pigment. Skin pigmentation is induced both by UVB and UVA rays. METHODS: The in vivo protection by sunscreens against pigmentation was studied using the determination of a level of protection against pigmentation based on the standardized sun protection factor (SPF) test method. The method includes delayed UVB and UVA pigmentations. The level of prevention against pigmentation was determined 7 days after exposure to solar-simulated radiation by visual assessment. It was calculated using the ratio of the minimal pigmenting dose on protected skin to the minimal pigmenting dose on unprotected skin. Broadspectrum UVB/UVA filters, Mexoryl SX and Mexoryl XL, and complete formula were tested. RESULTS: Protection against pigmentation correlates with the concentration of Mexoryl SX. The levels of protection obtained show a synergetic effect of Mexoryl SX when associated with Mexoryl XL. When different products having the same SPF (same protection against erythema) and different levels of UVA protection are compared, only sunscreen products with a high level of UVA protection show a similar level of protection against sunburn and pigmentation. Products with low UVA protection have a lower capacity of preventing induced pigmentation compared with their efficacy against erythema. CONCLUSIONS: These studies have evidenced that SPF determination was not sufficient to account for the efficiency in preventing pigmentation and that UVA protection was an essential part of this prevention.


Assuntos
Cânfora/análogos & derivados , Pigmentação da Pele/efeitos da radiação , Protetores Solares/uso terapêutico , Raios Ultravioleta/efeitos adversos , Adolescente , Adulto , Canfanos , Cânfora/administração & dosagem , Cânfora/uso terapêutico , Sinergismo Farmacológico , Eritema/prevenção & controle , Humanos , Mesilatos/administração & dosagem , Mesilatos/uso terapêutico , Pessoa de Meia-Idade , Doses de Radiação , Ácidos Sulfônicos , Queimadura Solar/prevenção & controle , Luz Solar/efeitos adversos , Protetores Solares/administração & dosagem , Fatores de Tempo , Triazóis/administração & dosagem , Triazóis/uso terapêutico
20.
Exp Dermatol ; 11 Suppl 1: 28-32, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12444956

RESUMO

It is well established that ultraviolet radiation has immunomodulatory effects which may be involved in skin cancer. Recent studies have shown that UVA radiation (320-400 nm) as well as UVB (290-320 nm) is immunosuppressive. This means that sunscreens which mainly absorb UVB (protection against erythema) may be less effective in preventing UVR-induced immunosuppression than broad-spectrum products. We have studied the effects of UVA exposure on the human delayed-type hypersensitivity response (DTH) and compared the efficacy of sunscreens having different levels of UVA protection under both solar-simulated radiation (SSR) chronic exposures or acute exposure and outdoor real-life solar exposure conditions. DTH was assessed using recall antigens. Our studies clearly demonstrate the role of UVA in the induction of photoimmunosuppression together with the need for sunscreen products providing efficient photoprotection throughout the entire UV spectrum. These data suggest that sun protection factor may not be sufficient to predict the ability of sunscreens for protection from UV-induced immune suppression. Determining the level of UVA protection is particularly necessary, because UVA seems to have a relatively low contribution to erythema but is highly involved in immunosuppression.


Assuntos
Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/efeitos da radiação , Protetores Solares/farmacologia , Raios Ultravioleta/efeitos adversos , Adulto , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/efeitos da radiação , Exposição Ambiental , Feminino , Humanos , Masculino , Luz Solar/efeitos adversos , Protetores Solares/normas , Fatores de Tempo
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