Research progress and directions in photodermatology / 中华皮肤科杂志

As an important subdiscipline of dermatology, photodermatology has developed rapidly in recent years. It is not only theoretical science of photodamage-related dermatoses, but also practical science of treatment of photodamage-related dermatoses. This article introduces the basis of photobiology, the pathogenesis of photodamage-related dermatoses, and research hotspots in sunscreens, and elaborates new progress in the clinical application of targeted phototherapy and home phototherapy, with a view to providing a theoretical basis and practical guidance for the treatment of photodamage-related dermatoses.

Photosensitive rash induced by nivolumab

Abstract The therapeutic approach to metastatic melanoma has revolutionized the clinical course of this disease. Since 2011, different immunotherapeutic drugs have been approved. Nivolumab is a humanized immunoglobulin IgG4 monoclonal antibody that binds to the PD-1 receptor, blocking its interaction with his ligand PD-L1. The authors present a new case of photosensitivity induced by nivolumab. The photo exposed distribution of the eruption, the sun exposure prior to the beginning of the eruption, and the chronological relationship with the beginning of the treatment are data that have allowed us to confirm the suspected clinical diagnosis.

Basic principles of photobiomodulation and its application in dermatology / 中华皮肤科杂志

Photobiomodulation, also known as photochemical modulation, refers to the use of low-power light from various sources to induce photophysical and photochemical modulation without thermal injury in the body. Photobiomodulation is related to the wavelength and energy of light. Target chromophores for light of different wavelengths include cytochrome C oxidase, opsin, porphyrin, etc., and the parameters such as power density, spot size, and energy density determine the energy of light. At present, many in vivo and in vitro studies have confirmed the application potential of photobiomodulation in the treatment of various skin diseases.

Evaluation of ex vivo melanogenic response to UVB, UVA, and visible light in facial melasma and unaffected adjacent skin,

Abstract Background: The independent role of solar radiation in the differential melanogenesis between melasma and adjacent skin is unknown. Objectives: To assess the melanogenic responses of skin with facial melasma and of the adjacent skin to UVB, UVA, and visible light, in an ex vivo model. Methods: This was a quasi-experimental study involving 22 patients with melasma. Facial melasma and adjacent skin samples were collected and stored in DMEM medium, at room temperature. One fragment was placed under the protection from light, while another was exposed to UVB, UVA, and visible light (blue-violet component): 166 mJ/cm2, 1.524 J/cm2, and 40 J/cm2, respectively. Subsequently, all samples were kept for 72 hours in a dark environment and stained by Fontana-Masson to assess basal layer pigmentation, dendrites, and melanin granulation. Results: Effective melanogenesis was observed in the basal layer in melasma and in the normal adjacent skin after all irradiations (p< 0.01), with the following median increment: UVB (4.7% vs. 8.5%), UVA (9.5% vs. 9.9%), and visible light (6.8% vs. 11.7%), with no significant difference between anatomical sites. An increase in melanin granulation (coarser melanosomes) was observed only after irradiation with UVA and only in the skin with melasma (p= 0.05). An increase in the melanocyte dendrite count induced by UVB radiation was observed in both anatomical sites (p≤ 0.05). Study limitations: Use of an ex vivo model, with independent irradiation regimes for UVB, UVA, and visible light. Conclusions: Melanogenesis induced by UVB, UVA, and visible light was observed both in melasma and in the adjacent skin. The morphological patterns suggest that different irradiations promote individualized responses on the skin with melasma.

Prurigo actínico en un centro dermatológico de referencia en Colombia: 108 casos / Actinic prurigo in a dermatological reference center in Colombia: 108 cases

Introducción. El prurigo actínico es una fotodermatosis crónica. Afecta con mayor frecuencia a la población latinoamericana, predomina en mujeres y compromete la piel expuesta al sol, las conjuntivas y los labios. Objetivo. Actualizar la información sobre las características clínico-epidemiológicas y el tratamiento de pacientes con prurigo actínico en Colombia. Materiales y métodos. Se hizo un estudio de corte transversal que incluyó los registros clínicos de pacientes con prurigo actínico atendidos en el Servicio de Fotodermatología del Hospital Universitario Centro Dermatológico Federico Lleras Acosta entre el 2011 y el 2016, y se describieron sus características demográficas, clínicas e histopatológicas, así como su tratamiento. Resultados. Se incluyeron 108 pacientes, el 71,3 % de ellos mujeres y el 28,7% hombres, con predominio de los fototipos III-IV (70 %). La enfermedad se había iniciado durante la primera década de vida en el 66,4% de los casos y el 25 % de los pacientes tenía antecedentes familiares de la enfermedad. Las lesiones predominaban en el rostro (93,5 %), los antebrazos (79,6 %) y el dorso de las manos (70,4 %). También, se documentó compromiso ocular (87,9 %) y de los labios (88,8 %). Se hizo la prueba de fotoprovocación con radiación ultravioleta A en el 25 % de los casos y biopsia cutánea en el 19,4 %. Todos los pacientes se trataron con protección solar química y física. En los casos leves a moderados, se formularon corticoides tópicos (91,7 %) e inhibidores de la calcineurina (65,7 %), y en los graves, talidomida (33,3 %) y pentoxifilina (14,8 %). Conclusión. Las características de los pacientes colombianos con prurigo actínico son similares a las reportadas en otros países latinoamericanos: inicio temprano de la enfermedad, predominio en mujeres, compromiso frecuente de conjuntivas y labios, y adecuada respuesta al tratamiento tópico y sistémico.

Introduction: Actinic prurigo is a chronic photodermatosis. It affects the Latin American population more frequently, predominantly women, and involves the sun-exposed areas of the skin, conjunctiva, and lips. Objective: To update the information on the clinical-epidemiological characteristics and treatment of patients with actinic prurigo in Colombia. Materials and methods: We conducted a cross-sectional study including the medical records of patients with actinic prurigo treated in the Photodermatology Service of Hospital Universitario Centro Dermatológico Federico Lleras Acosta between 2011 and 2016. We described the demographic, clinical, histopathological, and treatment characteristics of the patients. Results: We included 108 patients, 77 (71.3%) were women and 31 (28.7%) men, mainly with phototypes III-IV (70%). The disease had begun during the first decade of life in 66.4% of the cases and 25% of the patients had a family history with the condition. The lesions predominated on the face (93.5%), forearms (79.6%), and back of the hands (70.4%). Ocular (87.9%) and lip (88.8%) involvement was also documented. A photo-provocation test with UVA was performed in 25% of the cases and skin biopsies in 19.4%. Physical and chemical photoprotection was indicated in all patients. Mild to moderate cases were treated with topical corticosteroids (91.7%) and calcineurin inhibitors (65.7%) while severe cases received thalidomide (33.3%) and pentoxifylline (14.8%). Conclusion: The characteristics of actinic prurigo patients in Colombia are similar to those reported in other Latin American countries: early onset of the disease, predominance in women, frequent involvement of conjunctiva and lips, and adequate response to topical and systemic treatment.

Standardization of organoid culture for evaluation of melanogenesis induced by UVB, UVA and visible light

Abstract Background: Organoid cultures are primary cultures that maintain architectural characteristics and the relationships between cells, as well as the extracellular matrix. They are alternatives for pathophysiological or therapeutic investigation rather than animal and in vitro tests. Objective: Development of a cutaneous organoid culture model, aiming at the study of radiation-induced melanogenesis. Method: A validation study, which involved biopsies of the skin of the back of the adult ear. One sample was irradiated with different doses of UVB, UVA, or visible light (VL); the other was maintained in the dark for 72 h. The viability of the tissues was evaluated from the morphological and architectural parameters of the histology, and the expression of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, by real-time polymerase chain reaction (PCR). The radiation-induced melanin pigmentation was standardized according to the doses of each radiation and evaluated by digital image analysis (Fontana-Masson). Results: The primary skin culture was standardized at room temperature using DMEM medium. The doses of UVB, UVA, and VL (blue light) that induced differential melanogenesis were: 166 mJ/cm2, 1.524 J/cm2, and 40 J/cm2. The expression of the GAPHD constitutional gene did not differ between the sample of skin processed immediately after tissue collection and the sample cultured for 72 h in the standardized protocol. Study limitations: This was a preliminary study that evaluated only the viability and integrity of the melanogenic system, and the effect of the radiation alone. Conclusions: The standardized model maintained viable melanocytic function for 72 h at room temperature, allowing the investigation of melanogenesis induced by different forms of radiation.

Photobiological regulation of high glucose retinal vascular endothelial cells in rats by light emitting diode irradiation and its mechanisms / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To observe the application of light emitting diode(LED)irradiation in rat retinal vascular endothelial cells with high glucose and its effect and mechanism on photobioregulation. <p>METHODS:Rat retinal vascular endothelial cells were randomly divided into three groups: normal control group, high glucose model group, high glucose model light emitting diode irradiation group, and cells in the high glucose model light emitting diode group began to use light emitting diodes in the incubator 48h after modeling. The cells are irradiated. MTT cell apoptosis experiment was used to detect the apoptosis rate of each group; laser confocal microscope was used to observe the changes of intracellular calcium in retinal vascular endothelial cells; Western blot was used to detect the phosphorylated serine-threonine kinase(P-AKT)protein in each group expression.<p>RESULTS: The apoptosis rates of normal control group, high glucose model group, and high glucose model light emitting diode irradiation group were 7.54%±2.67%, 31.69%±5.74%, and 21.65%±3.52%, respectively(<i>P</i><0.05). In the normal control group, the cytoplasm with weak Ca2+ fluorescence showed green fluorescence with a pixel value of 192.65±50.54. In the high-sugar model group, the cytoplasm showed a stronger green fluorescence with a fluorescent pixel value of 710.69±100.38. The green fluorescent pixel value was 430.47±80.67, which was significantly higher than the normal control group, but significantly lower than the high-sugar model group. The intra-Ca2+ fluorescence pixel values in the three groups were statistically significant(<i>P</i><0.05). The amount of phosphorylated serine-threonine kinase(P-AKT)protein in these three groups of cells was 10.26±2.47, 2.35±0.16, 7.46±1.64, respectively(<i>P</i><0.05).<p>CONCLUSION: High-glucose environment inhibits the activity of threonine kinase pathway, which has an effect on calcium homeostasis of rat retinal vascular endothelial cells and promotes apoptosis. Low-intensity led irradiation can activate threonine kinase pathway and reduce the apoptosis rate caused by high glucose, which is of great application value.

Evaluation of 25 years of phototherapy for treating psoriasis at a teaching hospital in southern Spain

AbstractBACKGROUND:For years, phototherapy has been used in a wide range of skin diseases, which is unsurprising as skin is the anatomical feature most directly exposed to light, especially in psoriasis. Although the role of light therapy has been replaced by different therapeutic modalities in recent years, this treatment is now an established option for many skin diseases.OBJECTIVES:The aim was to characterize the patient population thathad received the aforementioned treatment in the Virgen Macarena Health Area in Seville (Spain) between June 1985 and October 2011.METHODS:We have designed a descriptive study with a univariate analysis covering 443 treatments with light therapy, all administered to the same number of patients suffering from psoriasis.RESULTS:79.15% of patients were discharged due to improvement or healing, while the 20.85% were discharged due to other reasons. The average total accumulative dose was 131.53 J/cm2. We do not detected an increase in proportion in patients for develop NMSK after light therapy treatment.CONCLUSIONS:We consider that phototherapy is still an effective and efficient treatment that will have to be reconsidered in the current macroeconomic context.

Proteção oferecida por fotoprotetores contra luz visível ? uma proposta de avaliação / Sunscreen protection against visible light: a new proposal for evaluation

Introdução: Têm sido desenvolvidos fotoprotetores pigmentados, com a combinação de filtros inorgânicos não particulados e pigmentos opacos, para a proteção contra a luz visível. Ainda não foi apresentado, entretanto, método confiável para a medida dessa proteção. Objetivo: O objetivo do estudo foi avaliar a eficácia de fotoprotetores brancos e coloridos na proteção contra a luz visível. Métodos: Foram avaliados 20 fotoprotetores comercializados no mercado brasileiro, sendo 13 produtos classificados como coloridos, e sete como brancos. Medidas colorimétricas foram realizadas para classificação da luminosidade e da translucidez dos produtos quando aplicados em placas de polimetilmetacrilato, e medidas espectrofotométricas foram calculadas para avaliação da absorbância na faixa de luz visível, entre 400 e 450nm, utilizando-se como parâmetro a eficácia absortiva na faixa de luz visível (Evis). Resultados: Produtos coloridos apresentaram Evis superior à dos produtos brancos. A análise estatística mostrou que há forte correlação entre a eficácia absortiva e a luminosidade e translucidez do produto, e não houve correlação entre a eficácia absortiva e o valor de FPS dos produtos. Conclusões: O uso da Evis mostrou-se parâmetro útil na avaliação de eficácia de fotoprotetores na proteção contra a luz visível. A presença de pigmentos nos produtos coloridos confere maior eficácia fotoprotetora dentro dessa faixa.

Introduction: In order to protect against visible light, pigmented sunscreens have been developed by combining organic non-particulate sunscreens and opaque pigments. No reliable method has yet been proposed to measure the protection offered by these pigments. Objective: To evaluate the effectiveness of white and colored sunscreens in the protection against visible light. Methods: Twenty sunscreens marketed in Brazil were evaluated (13 colored and 7 white). Colorimetric measurements were used to classify the brightness and translucency of the roducts, which were applied to polymethylmethacrylate sheets. Spectrophotometric measurements were taken to evaluate the product's absorbance within the visible light spectrum between 400 and 450 nm, using the Absorptive Efficacy in the visible light range as a parameter. Results: Colored products presented a higher Evis than white products. Statistical analysis demonstrated that there is strong correlation between absorptive effectiveness and the product's brightness and translucency. No correlation was verified between absorptive effectiveness and the products' sun protection factor. Conclusions: Absorptive efficacy in the visible light range was a useful parameter in the assessment of sunscreens' effectiveness in protecting against visible light. Pigmented products provide more effective photoprotection within that band.

Comparação do fototipo entre caucasianos e orientais / Phototype comparison between caucasian and asian skin types

Introdução: A avaliação da resposta cutânea à exposição à radiação ultravioleta tem grande importância na prática dermatológica. De uma variedade de métodos, a classificação dos fototipos de pele de Fitzpatrick é a mais utilizada. Simples e prática, permite avaliar o risco de fotodano e câncer de pele, além de auxiliar na definição dos tratamentos com luz.Apesar disso, parece haver considerações em relação aos não caucasianos. Objetivo: Comparar a avaliação subjetiva do fototipo com a classificação de Fitzpatrick em pacientes caucasianas e orientais. Métodos: Quarenta e duas mulheres caucasianas e orientais foram classificadas de acordo com três métodos de avaliação (clínico, Fitzpatrick e Fitzpatrick modificado). Os dados foram coletados através de questionário e analisados por métodos não paramétricos. Resultados: Na comparação entre a avaliação médica, e as classificações de Fitzpatrick eFitzpatrick modificada não houve diferença estatisticamente significativa dentro de cada grupo. Conclusões: Com base nesses resultados, pode-se concluir que os três métodos são equivalentes na avaliação do fototipo. Estudos com amostra populacional maior ainda serão necessários.

UVB suscetibilidade como fator de risco para o desenvolvimento da hanseníase virchowiana / UVB susceptibility as a risk factor to the development of lepromatous leprosy

FUNDAMENTOS: A radiação ultravioleta B (RUVB) é o mais importante fator ambiental capaz de modificar a função imunológica da pele humana. OBJETIVO: estudar a associação entre o fenótipo de suscetibilidade ou resistência à radiação RUVB e as formas polares da hanseníase. MATERIAL E MÉTODOS: foram avaliados 38 pacientes com hanseníase virchowiana (MHV) e 87 pacientes com hanseníase tuberculoide (MHT) de acordo com a classificação de Ridley e Jopling (1966). Todos os pacientes foram submetidos ao teste para determinação do fenótipo de suscetibilidade ou resistência à RUVB por meio da aplicação de um disco de dinitroclorobenzeno (DNCB) a 2 por cento em uma área de pele previamente irradiada com duas vezes a dose eritematosa mínima (DEM). Após 21 dias, outra aplicação de um disco similar de DNCB a 0,05 por cento na região escapular (área não exposta à RUVB) foi realizada para avaliar se houve sensibilização, com leitura após 48 horas. Os pacientes que apresentaram reação positiva ao DNCB foram considerados UVB-resistentes e o oposto foi considerado para aqueles que não apresentaram resposta (UVB-suscetíveis). RESULTADOS: A frequência de UVB-suscetíveis foi de 63,2 por cento (24 pacientes) no grupo MHV e 34,4 por cento (30 pacientes) no grupo MHT (OR = 3,26; IC = 1,36-7,87; x² = 7,73; p = 0,005). CONCLUSÃO: Os resultados sugerem que a UVB-suscetibilidade é um fator de risco para o desenvolvimento da MHV.

BACKGROUNDS: Ultraviolet radiation B (UVRB) is the most important environmental factor capable of altering the immune function of human skin. OBJECTIVE: To evaluate the association of the phenotypes of susceptibility or resistance to ultraviolet radiation B (UVRB) and the polar forms of leprosy. MATERIAL AND METHODS: We evaluated 38 patients with lepromatous leprosy (LL) and 87 patients with tuberculoid (TT) leprosy, according to the classification by Ridley and Jopling (1966). All the patients were submitted to a test to determine the phenotypes of susceptibility or resistance to UVRB through the application of a 2 percent dinitrochlorobenzene (DNCB) disc to a previously irradiated area with twice the minimal erythema dose (MED). After 21 days, a similar disc soaked in 0.05 percent DNCB was applied to the scapular area (unexposed to UVRB) to check for sensitiveness, with reading of the results after 48 hours. The patients that showed a positive reaction to DNCB were considered resistant (UVB-R) and those who did not show any reaction were considered susceptible (UVB-S). RESULTS: The frequency of UVB-S individuals was 63.2 percent (24 patients) in the LL group and 34.4 percent (30 patients) in the TT group (OR=3.26; IC=1.36 - 7.87; x²=7.73; p=0.005). CONCLUSION: Our results suggest that UVB-susceptibility is a risk factor to the development of lepromatous leprosy (LL).

UVB: suscetibilidade no melanoma maligno / UVB: susceptibility in malignant melanoma

FUNDAMENTOS: Está bem definido que a radiação ultravioleta provoca depleção imunológica na pele, permitindo o desenvolvimento de tumores cutâneos malignos. A maioria dos pacientes de cânceres da pele não melanomas são considerados UVB-suscetíveis. OBJETIVOS: Estudar a UVB-suscetibilidade nos pacientes com melanoma maligno e se este é um fator de risco para o desenvolvimento desse câncer. MÉTODOS: Foram selecionados 88 voluntários divididos em dois grupos: grupo-controle saudável (n=61) e grupo de portadores de melanoma (n=27), todos identificados de acordo com os critérios: tipo histológico, nível de invasão, fotótipos de pele, sexo e idade. A suscetibilidade à radiação ultravioleta B (UVB) foi medida pela reação de hipersensibilidade ao contato com o difenciprone nos voluntários sensibilizados em áreas previamente irradiadas. RESULTADOS: A suscetibilidade à radiação UVB foi de 81,5 por cento nos pacientes com melanoma maligno e de 31,2 por cento no grupo-controle. O risco de um indivíduo desenvolver o melanoma maligno foi 9,7 vezes maior do que nos indivíduos UVB-resistentes. CONCLUSÕES: A UVB-suscetibilidade pode ser considerada um fator de risco importante para o desenvolvimento do melanoma maligno.

BACKGROUND: It is well established that UV radiation provokes an immunological depletion in the skin, enabling the development of malignant cutaneous tumors. Most nonmelanoma skin cancer patients are considered to be UVB-susceptible. OBJECTIVE: To study the behavior of UVB- susceptibility in malignant melanoma (MM) patients and whether this is a risk factor to the development of MM. METHODS: Eighty-eight volunteers were selected and divided into two groups: healthy control group (n = 61) and MM group (n = 27), which were identified according to the following clinical criteria: histopathological type, level of invasion, skin phototype, sex and age. Susceptibility to ultraviolet B (UVB) radiation was measured by the onset of a contact hypersensitivity reaction to diphenylcyclopropenone among individuals sensitized in previously irradiated areas. RESULTS: Susceptibility to UVB radiation was 81.5 in the MM group and 31.2 percent in the control group. The risk of an UVB-susceptible individual to develop MM was 9.7 times higher than when UVB resistant. CONCLUSION: UVB susceptibility should be considered an important risk factor to the development of this type of cancer.

Terapêutica fotodinâmica com ácido delta-aminolevulínico e luz de diodos em ceratoses actínicas / Photodynamic therapy with delta-aminolevulinic acid and light-emitting diodes in actinic keratosis

FUNDAMENTOS: A terapêutica fotodinâmica é técnica de tratamento em que se aplica uma substância fotossensibilizante nos tecidos ativada por uma fonte de luz de comprimento de onda específico, gerando destruição celular seletiva. Estudam-se novas fontes de luz que possam ser usadas no tratamento de ceratoses actínicas. OBJETIVOS: Avaliar a efetividade da terapêutica fotodinâmica com ácido delta-aminolevulínico utilizando como fonte de luz um aparelho emissor de luz de diodos no tratamento de ceratoses actínicas de face e membros superiores. MÉTODOS: Dezoito pacientes com ceratoses actínicas na face ou membros superiores realizaram uma aplicação de creme de ácido delta-aminolevulínico a 20 por cento e foram submetidos à exposição de luz de diodos, comprimento de onda de 630 nm. RESULTADOS: Foram tratadas 328 ceratoses actínicas, obtendo-se cura clínica completa em 210 (64,0 por cento) após 24 semanas. Lesões do dorso das mãos apresentaram cura clínica completa em 49,2 por cento; nas demais áreas esse valor foi de 81,4 por cento. Não houve registro de efeitos adversos graves, e obteve-se bom grau de satisfação dos pacientes com os resultados. CONCLUSÃO: A terapêutica fotodinâmica com fonte de emissão de luz de diodos mostrou-se eficaz e bem tolerada para tratamento de ceratoses actínicas, com resultados semelhantes aos encontrados na literatura utilizando outras fontes luminosas.

BACKGROUND: Photodynamic therapy is a form of treatment in which a photosensitizing substance is applied to tissue and activated by a light source at a specific wavelength, thus selectively destroying cells. New light sources are being evaluated for use in the treatment of actinic keratoses. OBJECTIVES: To evaluate the efficacy of photodynamic therapy with delta-aminolevulinic acid using a light emitting diode device as a light source in the treatment of actinic keratoses of the face and upper limbs. METHODS: Eighteen patients with actinic keratoses of the face or upper limbs received an application of a 20 percent delta-aminolevulinic acid cream and were submitted to diode light irradiation at a wavelength of 630 nm. RESULTS: A total of 328 actinic keratoses were treated, obtaining complete cure in 210 (64.0 percent) after 24 weeks. Lesions situated on the back of the hands were clinically cured in 49.2 percent of cases compared to 81.4 percent in the cases of lesions in other areas. There was no record of any severe adverse effects and patient satisfaction with the results was high. CONCLUSION: Photodynamic therapy with a diode light emitting source proved effective and well-tolerated for the treatment of actinic keratoses, with results similar to those reported in the literature with other light sources.