Xeroderma pigmentosum: case report / Xeroderma pigmentoso: relato de caso

Abstract Objective: The aim of this study was to describe the disease and treatment and to alert health professionals for the identification of signs and symptoms and the need for an early diagnosis in patients with xeroderma pigmentosum (XP). Case description: An 8-year-old male patient was referred to the Joana de Gusmão Hospital (HIJG) in 2021 for evaluation and specialized care. Previously, the child was followed in his place of origin by oncologic and palliative care, where he was submitted to surgeries and chemotherapy. He was admitted to the HIJG using vismodegib, acitrein, tramadol, and solar protective measures. On physical examination, there were tumors and disseminated macular verrucous and ulcerated lesions. The imaging examination showed solid and expansive lesions on the face, and atelectasis and fibroscarring changes in the lung. The histopathological report proved the existence of melanocanthoma, carcinoma, and pyogenic granuloma. After the evaluation of the case, no surgery, chemotherapy, or radiotherapy was performed. It was decided to maintain the palliative treatment and to continue the use of tramadol for pain, and vismodegib and acitretin were used to control carcinomas and prophylactic measures. Comments: The XP is a rare disease of autosomal recessive inheritance whose mechanism comes from failure in the DNA repair by exposure to ultraviolet rays, resulting in lesions on the skin and mucous membranes. They start as sunburns and can progress to melanosis, areas with altered pigmentation, premature aging, poikiloderma, and areas of high risk for neoplasms.

RESUMO Objetivo: Descrever a patologia e o tratamento realizado e alertar profissionais de saúde sobre os sinais e sintomas e sobre a necessidade de diagnóstico precoce em pacientes com xeroderma pigmentoso (XP). Descrição do caso: Paciente do sexo masculino, oito anos, foi encaminhado ao Hospital Joana de Gusmão (HIJG) em 2021, com dianóstico de XP, para avaliação e atendimento especializado. Anteriomente, encontrava-se em serviço de oncologia e de cuidados paliativos em sua cidade de origem, mas já realizara cirurgias e quimioterapias previamente. Foi internado no HIJG em uso de vismodegibe, acitretina, tramadol e medidas de proteção solar. Ao exame físico, apresentou lesões maculares, verrucosas, ulceradas e tumores pelo corpo. Os exames de imagem revelaram lesões sólidas e expansivas na face e atelectasias e alterações fibrocicroscópicas no pulmão. O laudo histopatológico comprovou a existência de melanocantoma, carcinoma e granuloma piogênico. Após a avaliação do caso, optou-se por não realizar cirurgias, quimioterapia nem radioterapia. Decidiu-se manter o tratamento paliativo, continuando o uso de tramadol para dor, vismodegibe e acitretina para o controle de carcinomas e profilaxia à exposição ao sol. Comentários: O XP é uma doença rara de herança autossômica recessiva, cujo mecanismo provém de falha no reparo do DNA pela exposição à luz ultravioleta, resultando em lesões de pele e mucosas. Inicia-se como queimaduras solares e pode avançar para melanoses, áreas com pigmentação alterada, envelhecimento precoce, poiquilodermia e áreas de alto risco neoplásico.

Fibroblast morphology, growth rate and gene expression in facial melasma

Abstract Background: In addition to melanocytic hyperfunction, changes are observed in the upper dermis of melasma, and fibroblasts play a central role in collagen synthesis and pigmentation induction. Objective: To explore the morphology, growth rate, and gene expression profile of fibroblasts from the skin with melasma in comparison to fibroblasts from the adjacent healthy skin. Methods: Ten women with facial melasma were biopsied (lesion and adjacent healthy skin), and the fragments were processed for fibroblast culture. Samples from five participants were seeded to evaluate growth (days 2, 5 and 8) and senescence (SA-β-gal) curves. The samples from the other participants were submitted to real-time PCR to comparatively evaluation of the expression of 39 genes. Results: Cultured fibroblasts from melasma skin were morphologically less fusiform in appearance and on average a 34% (95% CI 4%-63%) greater proportion of cells labeled with SA-β-gal than the fibroblasts from the adjacent skin. The cell growth rate was lower for the melasma samples after eight days (p < 0.01). The WNT3A, EDN3, ESR2, PTG2, MMP1, and SOD2 genes were up-regulated, whereas the COL4A1, CSF2, DKK3, COL7A1, TIMP4, CCL2, and CDH11 genes were down-regulated in melasma skin fibroblasts when compared to the ones from adjacent healthy skin. Study limitations: Small sample size; absence of functional tests. Conclusions: Fibroblasts from the skin with melasma showed a lower growth rate, less fusiform morphology and greater accumulation of SA-β-gal than those from adjacent photo exposed skin. Moreover, their gene expression profile comprised factors that may contribute to upper dermis damage and sustained melanogenesis.

UVB irradiation differential regulate miRNAs expression in skin photoaging

Abstract Background: UVB irradiation can cause acute damage such as sunburn, or photoaging and melanoma, all of which are major health threats. Objective: This study was designed to investigate the mechanism of skin photoaging induced by UVB radiation in mice through the analysis of the differential expression of miRNAs. Methods: A UVB irradiation photoaging model was constructed. HE and Masson special stains were used to examine the modifications in the epidermis and dermis of mice. The miRNA expression profiles of the mouse skin model exposed to UVB radiation and the normal skin of mice were analyzed using miRNA-sequence analysis. GO and Pathway analysis were employed for the prediction of miRNA targets. Results: A total of 23 miRNAs were evaluated for significantly different expressions in comparison to normal skin. Among them, 7 miRNAs were up-regulated and 16 were down-regulated in the skin with photoaging of mice exposed to UVB irradiation. The differential expression of miRNA is related to a variety of signal transduction pathways, among which mmu-miR-195a-5p and mitogen-activated protein kinase (MAPK) signal pathways are crucial. There was a significant differential expression of miRNA in the skin of normal mice in comparison with the skin with photoaging induced by UVB irradiation. Study limitations: Due to time and energy constraints, the specific protein level verification, MAPK pathway exploration, and miR-195a-5p downstream molecular mechanism need to be further studied in the future. Conclusions: UVB-induced skin photoaging can be diagnosed and treated using miRNA.

Sunscreen lotions in the dermatological prescription: review of concepts and controversies

Abstract The skin is regularly exposed to several environmental aggressions, including solar radiation, whose biological effects can induce sunburn, dyschromia, skin aging and cancer. Among the photoprotection measures, sunscreens comprise a relevant part of the strategy aimed to prevent solar radiation damage and, for effective action, the patient must adhere to the product use and the latter, in turn, must follow technical parameters to promote adequate protection. This review article brings together the most current and relevant concepts about photoprotection for dermatological use, including the challenges for their formulation, the risks of certain photoprotective active substances for individual and environmental safety and the importance of stringency in determining the product efficacy, considering the regulatory aspects, highlighting relevant differences between Brazil and other countries. Thus, when assessing a sunscreen, not only the visual aspects and sensory perception will be immediately evaluated, but also the quality and suitability of the vehicle, the chemical composition of the formulation, the environmental risks, the photostability of the screening system, and the measurement of its protection spectrum. Technical knowledge of sunscreens can help dermatologists in this important role of educating patients about the best photoprotective strategies in each situation.

Actinic cheilitis in rural workers: prevalence and associated factors

ABSTRACT Objective To evaluate the prevalence of actinic cheilitis in rural workers and factors associated with the development of this condition. Methods A cross-sectional study was conducted in a city in Northeastern Brazil. Data were collected by clinical examination and use of a questionnaire validated with 300 rural workers. The χ2 test was employed to identify possible associations between the presence of actinic cheilitis and clinical and demographic variables. Multiple logistic regression analysis was performed using forward stepwise selection. A p value of 0.05 was considered significant. Results The prevalence of actinic cheilitis was 12.0% in the sample. The highest prevalence of actinic cheilitis was observed in white males, with low educational level, and an approximately 40-year history of sun exposure. Chronic lesions were commonly found in the lower lip and were characterized by scaling, dryness, and mild edema. Skin color, sex, educational level of patients, and cumulative sun exposure (in years), were identified as predictors of development of actinic cheilitis. Conclusion Our results suggest the need to implement educational health strategies aimed to orient the population about risk factors and preventive measures of the disease. Appropriate clinical management of patients with actinic cheilitis is important for prevention of lip cancer.

Effectiveness of sunscreens and factors influencing sun protection: a review

Abstract The effectiveness of sun protection depends directly on the photo-protective product employed, the way it is used and the amount applied. Many studies report that sunscreens are often applied incorrectly, at amounts much lower than those recommended for the sun protection factor (SPF) specified on the label. When not used properly, the effectiveness of the product against sun exposure damage is reduced. Currently, sunscreens are available in a variety of different formulations and types, such as stick (bar), aerosol, cream, lotion, oil, tanning formulations and makeup. However, developing an effective stable photo-protective formula that can be correctly applied regardless of type poses a challenge, as effectiveness is dependent on several factors. Factors influencing effectiveness include sun exposure conditions (direct or indirect), level of protection (SPF), amount of product applied, maximum exposure period before reapplication, product type (spray, lotion, etc.), layer thickness required, coverage, and ability to spread and permeate into the skin. Studies comparing the effectiveness of different forms of sunscreens, the amount of product applied by consumers and SPF and UVA protection determined by validated methodologies, are lacking. Therefore, the objective of this study was to review the available literature on the topic and discuss the effectiveness of sunscreen formulations and factors influencing sun protection. This review was carried out on the scientific databases MEDLINE, PubMed and Scielo. Of the many publications retrieved, thirty-nine articles most relevant for this review were selected.

Mechanisms underlying synergistic induction and promotion of cutaneous squamous cell carcinoma in nude mice by ultraviolet light and human papillomavirus 16 E6 / 中华皮肤科杂志

Objective:To establish a xenograft model of cutaneous squamous cell carcinoma (CSCC) in nude mice, and to explore mechanisms underlying synergistic induction and promotion of CSCC in nude mice by ultraviolet radiation and human papillomavirus (HPV) infection.Methods:The human CSCC A431 cells were divided into 3 groups, namely HPV16 E6 overexpression group (LV-OE-HPV16 E6 group) transfected with adenovirus-mediated HPV16 E6 gene, empty vector group transfected with empty adenovirus vectors, and blank control group remaining untransfected. Using serum-free Dulbecco′s modified Eagle′s medium (DMEM) , A431 cells in the empty vector group and LV-OE-HPV16 E6 group were prepared into single-cell suspensions, which were subcutaneously inoculated into the left buttocks of SKH-1 nude mice separately, namely empty vector group ( n = 16) and LV-OE-HPV16 E6 group ( n = 16) . Tumor growth was observed and recorded for the mice every 3 days. When the tumor size reached 150 mm 3, the modeling was considered successful. After successful modeling, 8 mice in each group were irradiated with ultraviolet light at a dose of 1 440 mJ·cm -2·d -1 for 12 minutes each time, the other 8 mice in each group received no ultraviolet radiation, that is to say, all the 32 mice were divided into 4 groups: empty vector group, empty vector + UV group, LV-OE-HPV16 E6 group, and LV-OE-HPV16 E6 + UV group. After 4-week radiation, these nude mice were sacrificed, tumor weight and volume were measured, a tumor growth curve was drawn, immunohistochemistry study, Western blot analysis and real-time fluorescence-based quantitative PCR (qRT-PCR) were conducted to determine the protein and mRNA expression of Wnt1 and β-catenin in CSCC tissues collected from nude mice, respectively. For normally distributed measurement data, analysis of variance was used for intergroup comparisons, and least significant difference- t test for multiple comparisons; for non-normally distributed measurement data, rank sum test was used for intergroup comparisons. Results:Compared with the empty vector group (2.20 ± 0.24 g) , the tumor weight significantly increased in the empty vector + UV group (2.90 ± 0.36 g, t = 4.39, P < 0.001) , LV-OE-HPV16 E6 group (3.19 ± 0.32 g, t = 6.77, P < 0.001) , and LV-OE-HPV16 E6 + UV group (4.41 ± 0.18 g, t = 20.11, P < 0.001) ; the tumor volume was also significantly higher in the empty vector + UV group (1 033.12 ± 400.15 mm 3, t = 1.90, P < 0.001) , LV-OE-HPV16 E6 group (1 119.21 ± 447.57 mm 3, t = 2.21, P < 0.001) , and LV-OE-HPV16 E6 + UV group (1 464.29 ± 409.98 mm 3, t = 4.22, P < 0.001) than in the empty vector group (688.94 ± 319.31 mm 3) . Immunohistochemical study showed no significant difference in the protein expression of Wnt1 and β-catenin among the 4 groups ( F = 0.76, 0.71, respectively, both P > 0.05) ; Western blot analysis showed significant differences in the protein expression levels of Wnt1 and β-catenin among the 4 groups ( F = 16.74, 49.90, respectively, both P < 0.05) , which were significantly higher in the LV-OE-HPV16 E6 + UV group than in the empty vector group, empty vector + UV group and LV-OE-HPV16 E6 group (all P < 0.05) . qRT-PCR showed a significant difference in the mRNA expression of Wnt1 and β-catenin among the 4 groups ( F = 7.77, 8.38, respectively, both P<0.05) , and the LV-OE-HPV16 E6 + UV group showed significantly increased Wnt1 mRNA expression levels compared with the empty vector group, empty vector + UV group and LV-OE-HPV16 E6 group (all P < 0.05) . Conclusion:Ultraviolet radiation and HPV infection showed synergistic effect on the induction and promotion of CSCC.

Skin imaging technologies for photoaging / 中华皮肤科杂志

Skin photoaging not only affects the appearance, but also is associated with skin tumors. It is very important to objectively and effectively evaluate photoaging. Histopathological examination is the gold standard for the diagnosis of photoaging, but it can not be used repeatedly because of its invasiveness, and is not suitable for dynamic monitoring and evaluation of photoaging. Skin imaging technologies can realize in vivo, real-time and non-invasive two- or three-dimensional image analysis, which facilitate the visual assessment of skin photoaging. This review summarizes research progress in dermoscopy, reflectance confocal microscopy, high-frequency ultrasound and optical coherence tomography in evaluation of photoaging.

Efficacy and effectivity of UVC for disinfection of hospital materials of COVID-19 patients / Eficácia e efetividade do UVC para desinfecção de materiais hospitalares de pacientes com COVID-19 / Eficacia y efectividad de UVC para desinfección de material hospitalario de pacientes con COVID-19

Background and Objectives: After the beginning of the COVID-19 pandemic, more effective and efficient means were needed to disinfect hospital materials. The objective of our study is to evaluate the in vitro efficacy and the economic effectiveness of type C ultraviolet (UVC) irradiation for disinfection of materials used in the care of COVID-19 patients. Methods. Four bipartite Cled plates were inoculated with suspensions of 10,000 CFU/mL of Escherichia coli and Staphylococcus aureus strains, exposed to two 18W lamps, placed inside a laminar flow and incubated for quantitative growth assessments. The germicidal equipment was built: the "UVC box" was developed with two 18W lamps for use in materials returned to pharmacy and a "UVC closet" with two 60W lamps for surgical gowns exposure. The economic effectiveness was evaluated by comparing inventory costs with quarantine of materials versus UVC usage costs. Results. Microbiological inactivation in the plates started after 4 minutes with an efficiency close to 100% at 8 minutes. The "UVC box" reduced the time to release the material from 9 days to immediately, generating savings of approximately R$ 68,400, and the "UVC closet" changed the use of surgical gowns to 0.7/patient, compared to the usual of 1.5, generating savings of nearly 3,000 reais/month. The cost of installation and maintenance was R$ 1,500. Conclusions. The efficacy and effectiveness of the UVC system was proven, as well as the economy promoted by its installation.(AU)

Justificativa e Objetivos: Após o início da pandemia de COVID-19, meios mais efetivos e eficazes foram necessários para desinfetar materiais hospitalares. Este trabalho visa avaliar a eficácia in vitro e a efetividade econômica de luz ultravioleta tipo C (UVC) para desinfecção de materiais usados em pacientes com COVID-19. Métodos: Quatro placas bipartidas de Cled foram inoculadas com suspensões de 10.000 ufc/mL de cepas de Escherichia coli e Staphylococcus aureus, expostas a duas lâmpadas de 18W, colocadas dentro de um fluxo laminar e incubadas para avaliações quantitativas de crescimento. O equipamento germicida foi construído: uma "caixa UVC" com duas lâmpadas de 18W para materiais da farmácia e um "armário UVC" com duas lâmpadas 60W para exposição de capotes. A efetividade econômica foi avaliada comparando os custos de estoque, com quarentena de materiais versus custos de uso da UVC. Resultados: A inativação microbiológica nas placas se iniciou a partir de 4 minutos, com eficácia próxima a 100% aos 8 minutos. A "caixa de UVC" reduziu o tempo para liberação do material de 9 dias para imediato, gerando uma economia de aproximadamente R$ 68.400,00, e o "armário de UVC" alterou o uso de capotes para 0,7/paciente, comparado ao uso habitual de 1,5, gerando uma economia de 3.000 reais/mês. O custo de instalação e manutenção foi de R$ 1.500,00. Conclusão: Foi comprovada a eficácia e efetividade dos sistemas UVC, além da economia promovida por sua instalação.(AU)

Justificación y Objetivos. Después del inicio de la pandemia de COVID-19, se necesitaron medios más efectivos y eficientes para desinfectar los materiales hospitalarios. El artículo tiene como objetivo evaluar la eficacia in vitroy la efectividad económica de la luz ultravioleta tipo C (UVC) para desinfección de materiales utilizados en la atención al paciente con COVID-19. Métodos. Cuatro placas partidas Cledfueron inoculadas consuspensiones de 10,000 UFC/mL de cepas de Escherichia coliy Staphylococcusaureus, expuestas a dos lámparas de 18W, colocadas dentro del flujo laminar e incubadas para evaluaciones cuantitativas de crecimiento. Se construyó el equipo germicida: una "caja UVC" con dos lámparas de 18W para materiales de farmacia y un "armario UVC" con dos lámparas de 60W para exponerlas batas. La efectividad económica se evaluó comparando los costos de inventario con la cuarentena de materiales, versus loscostos de uso de UVC. Resultados. La inactivación microbiológica en las placas se inició a los 4 minutos con una eficiencia cercana al 100% a los 8 minutos. La "caja UVC" redujoeltiempo de liberacióndel material de 9 días a una liberación inmediata, economizando aproximadamente R$ 68.400 y el "armario UVC" cambióel uso de batas a 0,7/paciente, frente al uso habitual de 1,5, economizando aproximadamente 3.000 reales/mes. El costo de instalación y mantenimiento fue R$1.500. Conclusiones. La efectividad y eficaciadel sistema UVC fue comprobada, además de los resultados en la economía por su instalación.(AU)

Uso de un nuevo protocolo clínico fotográfico-computacional en el registro de la fluorescencia visible inducida por radiación ultravioleta en dientes humanos

RESUMEN: Los dientes humanos experimentan fluorescencia visible al ser sometidos a radiación ultravioleta, la cual varía de color a medida que el diente envejece. Objetivo: el presente estudio buscó desarrollar un protocolo clínico sencillo usando fotografía digital y análisis computacional para determinar la fluorescencia visible inducida por radiación ultravioleta (FVIUV) en dientes anteriores de pacientes de distintos grupos etarios. Materiales y Métodos: 35 participantes de 5 grupos etarios fueron reclutados. 70 incisivos centrales superiores fueron fotografiados utilizando como fuente de iluminación luz UV. Cada imagen obtenida fue analizada con el software computacional ImageJ para obtener las coordenadas de color en el espacio CIELab para la corona completa. Los datos obtenidos fueron analizados mediante las pruebas estadísticas de ANOVA y post-hoc de Tukey HSD. Resultados: Se obtuvieron las magnitudes de FVIUV en las tres dimensiones del espacio de color CIELab en la corona completa. Esta FVIUV se manifestó en el espectro del color verdeazulado para todos los grupos etarios, los cuales presentaron diferencias de saturación y luminosidad según tramo etario. Conclusiones: El protocolo aplicado en presente estudio permitió la cuantificación de la FVIUV dentaria en distintos grupos etarios.

ABSTRACT: Human teeth experience visible fluorescence when subjected to ultraviolet radiation, which varies in color as the tooth ages. Objective: The present study sought to develop a simple clinical protocol using digital photography and computational analysis to determine the difference in visible fluorescence induced by ultraviolet radiation (FVIUV) in anterior teeth of patients of different age groups. Materials and Methods: 35 participants from five age groups were recruited. 70 upper central incisors were photographed using UV light as the illumination source. Each image obtained was analyzed with ImageJ computer software to obtain the color coordinates in CIELab space for the entire crown. The data obtained was analyzed using the ANOVA and Tukey HSD post-hoc statistical tests. Results: Visible fluorescence magnitudes were obtained in the three dimensions of the CIELab color space in the complete crown. This FVIUV was registered in the spectrum of the blue-green color for all age groups, which presented differences in saturation and luminosity according to age group. Conclusions: The protocol applied in this study allowed the quantification of dental FVIUV in different age groups.

Corneal crosslinking efficacy in patients with keratoconus under 18 years of age / Eficácia do crosslinking corneano em portadores de ceratocone com idade inferior a 18 anos

ABSTRACT Purpose: Keratoconus presents certain specificities in pediatric patients compared with adults. The greatest challenge is because the disease is typically more severe and progresses faster in children. This retrospective study aimed to report crosslinking procedure in patients under 18 years of age and their follow-up for at least 24 months after the procedure. Methods: Overall, 12 eyes from 10 patients were studied and data, such as visual acuity with and without correction, maximum keratometry, corneal thickness, foveal thickness, and endothelial microscopy, were assessed at both preoperative and postoperative visits. Corneal crosslinking was performed in all patients. Results: A tendency toward reduced Kmax and improved Corrected Distance Visual Acuity at all postoperative moments. Only one of the 12 eyes exhibited increased Kmax of more than 1 D during a time frame longer than 12 months. Regarding pachymetry, a tendency for corneal thinning was observed in the first four months after surgery. Conclusion: Encouraging results were obtained regarding the stabilization of the disease, progression, and procedural safety, corroborating to other authors' findings. The significance of early diagnosis and short-term follow-up were highlighted.

RESUMO Objetivo: O ceratocone na população pediátrica apresenta algumas particularidades em relação à população adulta. O maior desafio é devido à doença ser geralmente mais severa e rapidamente progressiva em crianças. Métodos: Este artigo utiliza uma análise retrospectiva para relatar o uso do crosslinking em jovens menores de 18 anos e sua evolução pelo menos 24 meses após o procedimento. Foram estudados 12 olhos de 10 pacientes, e dados como acuidade visual com e sem correção, ceratometria máxima, espessura corneana, espessura foveal e microscopia endotelial avaliados no pré e pós-operatórios. O crosslinking corneano foi realizado em todos os pacientes pelo mesmo cirurgião. Resultados: Observou-se uma tendência de redução do valor do Kmax e melhora da acuidade visual corrigida em todos os momentos de pós operatório. Com relação à paquimetria, observou-se afinamento corneano do ponto mais fino, nos primeiros quatro meses de pós-operatório. Conclusão: Resultados encorajadores foram obtidos com relação à estabilização da doença, progressão e segurança do procedimento, corroborando com as conclusões de outros autores. A importância do diagnóstico precoce e do acompanhamento a curto prazo do paciente deve ser destacada.

Prevalência do uso de fotoproteção e fatores associados em feirantes / Prevalence of the use of photoprotection and associated factors in marketers / Prevalencia del uso de fotoprotección y factores asociados en feirantes

Objetivo: estimar a prevalência do uso de fotoproteção e associar aos fatores sociodemográficas, fototipo e fatores de riscos em feirantes. Métodos: trata-se de um estudo transversal com amostra de 150 feirantes cadastrados na Central de Abastecimento do Norte de Minas. Utilizou-se questionário acerca do perfil sociodemográfico, hábitos de exposição solar, medidas de fotoproteção e fatores de risco para neoplasia cutânea. Descreveram-se as frequências simples e porcentagens. A análise bivariada realizou-se por meio do teste qui-quadrado (x²) e Teste Exato de Fisher's. Considerou-se relevância estatística p < 0,05. Resultado: observou-se elevada prevalência do não uso da fotoproteção solar pelos feirantes (50%). Ademais, houve uma associação significativa entre fotoproteção e as variáveis cor dos olhos (p = 0,039), tempo de exposição (p = 0,000), horário de exposição (p = 0,057) e assistência médica (p = 0,005). Conclusão: feirantes de olhos escuros, que se expõem ao sol por mais de 3 horas, o dia inteiro e não procuram assistência médica, não usam fotoproteção

Objective: to estimate the prevalence of photoprotection use and to associate sociodemographic factors, phototype and risk factors in marketers. Methods: this is a cross-sectional study with a sample of 150 marketers registered at the Northern Minas Supply Center. A questionnaire about the sociodemographic profile, habits of sun exposure, measures of photoprotection and risk factors for cutaneous neoplasia was used. Simple frequencies and percentages were described. The bivariate analysis was performed using the chi-square test (x²) and Fisher's Exact Test. Statistical relevance was considered p <0.05. Results: there was a high prevalence of solar photoprotection not being used by farmers (50%). In addition, there was a significant association between photoprotection and the variables eye color (p = 0.039), exposure time (p = 0.000), exposure time (p = 0.057) and medical care (p = 0.005). Conclusion: dark-eyed marketers, who are exposed to the sun for more than 3 hours, all day and do not seek medical attention, do not use photoprotection

Objetivo: estimar la prevalencia del uso de fotoprotección y asociar a los factores sociodemográficos, fototipo y factores de riesgo en feriantes. Métodos: se trata de un estudio transversal con muestra de 150 feriantes registrados en la Central de Abastecimiento del Norte de Minas. Se utilizó un cuestionario sobre el perfil sociodemográfico, hábitos de exposición solar, medidas de fotoprotección y factores de riesgo para neoplasia cutánea. Se describieron las frecuencias simples y porcentajes. El análisis bivariado se realizó por medio de la prueba qui-cuadrado (x²) y la prueba exacta de Fisher's. Se consideró relevancia estadística p <0,05. Resultado: se observó elevada prevalencia del no uso de la fotoprotección solar por los feirantes (50%). Además, hubo una asociación significativa entre fotoprotección y las variables color de los ojos (p = 0,039), tiempo de exposición (p = 0,000), horario de exposición (p = 0,057) y asistencia médica (p = 0,005). Conclusión: los ojos oscuros, que se exponen al sol durante más de 3 horas, todo el día y no buscan asistencia médica, no usan fotoprotección

Role and action mechanism of microRNA-26a targeting EZH2 in ultraviolet A-induced photoaging of human skin fibroblasts / 中华皮肤科杂志

Objective:To investigate the expression of microRNA (miR) -26a in human skin fibroblasts during photoaging induced by ultraviolet A (UVA) , and to evaluate the effect of up-or down-regulation of miR-26a expression on the methylation level of the whole genome, the target gene enhancer of zeste homolog 2 (EZH2) and cell aging.Methods:Some human skin fibroblasts were irradiated with 10 J/cm 2 UVA once a day for 7 consecutive days, RNA was extracted on days 0, 3 and 7, and real-time quantitative reverse PCR (RT-PCR) was performed to determine the expression of miR-26a; miR-26a mimics and inhibitors were transfected into fibroblasts to up-or down-regulate the expression of miR-26a respectively, and fluorescence microscopy and RT-PCR were performed to determine the expression of miR-26a and evaluate the transfection efficiency. Some human skin fibroblasts were divided into 6 groups: blank control group receiving no treatment, UVA group treated with UVA irradiation according to the above method, miR-26a mimic group transfected with miR-26a-mimics, UVA+miR-26a mimic group transfected with miR-26a-mimics followed by UVA irradiation, miR-26a inhibitor group transfected with miR-26a inhibitors, UVA+miR-26a inhibitor group transfected with miR-26a inhibitors followed by UVA irradiation. On day 7, cells in each group were collected after the end of UVA irradiation. Then, flow cytometry was performed to detect cell cycle, DNA methylation quantitative detection kit was used to detect the methylation level of whole genome, RT-PCR was conducted to determine the mRNA expression of EZH2 (a histone-lysine N-methyltransferase enzyme) , DNA methyltransferase 1 (DNMT1) and miR-26a, and Western blot analysis was performed to determine the protein expression of EZH2 and DNMT1. Statistical analysis was carried out by using one-way analysis of variance and least significant difference- t test. Results:Compared with the unirradiated control group, the expression of miR-26a gradually increased in the UVA irradiation group over time during the culture, and there was a significant difference in the expression of miR-26a between the two groups after 7 days of UVA irradiation ( t=5.295, P < 0.05) . Strong fluorescence signals were observed in the miR-26a mimic-or miR-26a inhibitor-transfected fibroblasts, suggesting a high transfection efficiency. Flow cytometry showed that the proportion of cells at G1 phase significantly differed among the blank control group, UVA group, miR-26a mimic group, UVA+miR-26a mimic group, miR-26a inhibitor group, and UVA+miR-26a inhibitor group (52.82% ± 2.56%, 78.56% ± 4.34%, 53.63% ± 3.13%, 89.52% ± 4.17%, 54.39% ± 3.86%, 65.34% ± 4.78%, respectively; F=46.728, P < 0.01) , and significantly higher in the UVA group than in the blank control group ( t=8.848, P < 0.01) , higher in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group ( t=11.922, 3.154, P < 0.01, < 0.05, respectively) , and higher in the UVA+miR-26a inhibitor group than in the miR-26a-inhibitor group ( t=3.087, P < 0.05) , but significantly lower in the UVA+miR-26a inhibitor group than in the UVA group ( t=3.547, P < 0.05) . Detection of the genome-wide methylation level showed that the methylation level ( A450 value) significantly differed among the above groups (0.676 ± 0.024, 0.323 ± 0.043, 0.506 ± 0.035, 0.169 ± 0.024, 0.602 ± 0.036, 0.422 ± 0.029, respectively, F=97.402, P < 0.01) , and significantly lower in the UVA group than in the blank control group ( P < 0.01) , lower in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group (both P < 0.01) , and lower in the UVA+miR-26a inhibitor group than in the miR-26a inhibitor group ( P < 0.01) , but significantly higher in the UVA+miR-26a inhibitor group than in the UVA group ( P < 0.05) . RT-PCR and Western blot analysis showed significant differences in the mRNA and protein expression of EZH2 and DNMT1 respectively among the 6 groups (both P < 0.05) , which were significantly lower in the UVA group than in the blank control group ( P < 0.05) , lower in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group (both P < 0.05) , and lower in the UVA+miR-26a inhibitor group than in the miR-26a inhibitor group ( P < 0.05) , but significantly higher in the UVA+miR-26a inhibitor group than in the UVA group ( P < 0.05) . Conclusion:In the UVA irradiation-induced photoaging of skin fibroblasts, miR-26a expression was up-regulated, cellular proliferative activity and genome-wide methylation level decreased; up-regulation of miR-26a expression could down-regulate the expression of its target gene EZH2 and methylation-related gene DNM1, and promote cell photoaging, while down-regulation of miR-26a expression could up-regulate the expression of EZH2 and DNMT1, and inhibit cell photoaging.

The Association of Socioeconomic Status with the Burden of Cataract-related Blindness and the Effect of Ultraviolet Radiation Exposure: An Ecological Study / 生物医学与环境科学（英文）

Objective@#To assess the association of socioeconomic status with the burden of cataract blindness in terms of year lived with disability (YLD) rates and to determine whether ultraviolet radiation (UVR) levels modify the effect of socioeconomic status on this health burden.@*Methods@#National and subnational age-standardized YLD rates associated with cataract-related blindness were derived from the Global Burden of Disease (GBD) study 2017. The human development index (HDI) from the Human Development Report was used as a measure of socioeconomic status. Estimated ground-level UVR exposure was obtained from the Ozone Monitoring Instrument (OMI) dataset of the National Aeronautics and Space Administration (NASA).@*Results@#Across 185 countries, socioeconomic status was inversely associated with the burden of cataract blindness. Countries with a very high HDI had an 84% lower age-standardized YLD rate [95% confidence interval ( @*Conclusion@#Long-term high-UVR exposure amplifies the association of poor socioeconomic status with the burden of cataract-related blindness. The findings emphasize the need for strengthening UVR exposure protection interventions in developing countries with high-UVR exposure.

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.

Seasonal variation of vitamin D among healthy adult men in a subtropical region

SUMMARY OBJECTIVE: To evaluate seasonal variation of 25(OH)vitamin D [25(OH)D3] levels, and factors associated with it, in healthy adult men, who exercised outdoors for 50 min., at least twice a week, from 10AM to 4PM, in a Brazilian semitropical region. METHODS: Blood samples were collected at the end of each season for 25(OH)D3, measured by liquid chromatography with tandem mass spectrometry. Ultraviolet irradiation was estimated by radiometer, calculating the daily photobiological response to vitamin D synthesis in human skin (D-VitD). The prevalence of 25(OH)D3 <20ng/mL changed with the seasons (p=0.000): 8.7% (n=6/69), 1.5% (n=1/66), 0 (n=0/64), and 21.7% (n=13/60), respectively, at the end of winter, spring, summer, and autumn. The prevalence, adjusted for multiple comparisons, was higher in winter than summer (p=0.026), and in autumn than spring (p=0.001) and summer (p=0.000). There were no associations of 25(OH) D3 levels with BMI (p=0.207), body fat (p=0.064), and phototype (p=0.485), in univariate analysis. It was associated with D-VitD in the 30 days before blood sampling (p=0.000), after adjustment to body fat. The prevalence of 25(OH)D3 <30ng/mL varied seasonally (p=0.000): 69.6% (n=48/69), 68.2% (n=45/66), 43.8% (n=28/64), and 88.4% (n=53/60), respectively, in winter, spring, summer, and autumn. CONCLUSIONS: In a Brazilian subtropical region, a seasonal variation in 25(OH)D3 was observed in healthy adult males, although they spent at least 50 min outdoors twice a week, wearing shorts and T-shirts. 25(OH)D3 <20ng/mL was 21.7% in autumn; D-vitD 30 days prior to blood sampling was the only factor independently associated with 25(OH)D3 levels.

RESUMO OBJETIVOS: Avaliar a sazonalidade da 25(OH)vitamina D3 [25(OH)D3] e fatores associados em homens adultos saudáveis, que se exercitavam ao ar livre pelo menos 50 min duas vezes por semana, das 10 às 16h, em uma região subtropical. MÉTODOS: Sangue foi colhido no fim das estações para medir 25(OH)D3, por cromatografia líquida em tandem com espectroscopia de massas. A radiação ultravioleta foi estimada por radiômetro, calculando diariamente a resposta fotobiológica para sintetizar vitamina D na pele humana (D-VitD). RESULTADOS: A prevalência de 25(OH)D3 <20ng/mL foi sazonal (p=0.000): 8.7% (n=6/69), 1.5% (n=1/66), 0% (n= 0/64), e 21.7% (n=13/60), respectivamente, no final do inverno, primavera, verão e outono. A prevalência, ajustada para comparações múltiplas, foi maior no inverno do que no verão (p=0.026) e no outono do que na primavera (p=0.001) e verão (p=0.000). A 25(OH)D3 não se associou com o índice de massa corporal (p=0.207), gordura corporal (p=0.064) ou fototipo (p=0.485), na análise univariada. Associou-se à D-VitD nos 30 dias antes da coleta de sangue (p=0.000), ajustada para gordura corporal. Houve sazonalidade na prevalência de 25(OH)D3 <30ng/mL (p=0.000): 69.6% (n=48/69), 68.2% (n=45/66), 43.8% (n=28/64), e 88.4% (n=53/60), respectivamente, no inverno, primavera, verão e outono. CONCLUSÕES: Em uma região subtropical, houve sazonalidade na 25(OH)D3 em homens adultos, saudáveis, embora se exercitassem ao ar livre pelo menos 50 minutos duas vezes por semana, usando shorts e camiseta. 25(OH)D3 <20ng/mL foi 21.7% no outono e a D-vitD 30 dias antes da coleta do sangue foi o único fator associado de modo independente à 25(OH)D3.

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.

Conocimientos y hábitos de exposición solar en comerciantes ambulantes de un mercado de Chiclayo, Perú / Knowledge And Habits Of Solar Exposure In Street Traders Of A Market In Chiclayo, Peru

Objetivo: Determinar los conocimientos y hábitos de exposición solar en comerciantes ambulantes alrededor de un mercado de Chiclayo. Métodos: Se aplicó un cuestionario a 291 comerciantes ambulantes ubicados alrededor del mercado Modelo de Chiclayo, que evaluaron los hábitos de exposición solar, medidas de foto protección, antecedentes de quemaduras solares y cáncer de piel, asi como conocimientos de radiación ultravioleta y fuentes de información. Resultados: Las edades fueron, 18-25 (42,3%), 36-54 (38,1%), 55 -78 (19,6%). En nivel de educación, el 13,1% tiene primaria completa, el 32,6% tiene secundaria completa y el 8,2% superior completa. Al momento del estudio el 71,9% llevaban más de 3 años trabajando como comerciantes ambulantes. Los fototipos de los participantes fueron fototipo I (0,3%), fototipo II (4,5%), fototipo III (24,7%), fototipo IV (48,8%), fototipo V (19,6%), fototipo VI (2,15). Un 90 ± 3,5% reconoce que causa cáncer de piel, un 53,6% reconoce que una característica del envejecimiento de la piel por radiación son las manchas y verrugas, un 56% respondió que la radiación solar causa cataratas, un 52,92% respondió que la gente de piel blanca es más sensible a los rayos del sol. Un 48,5% de ellos declararon exponerse más de 6 horas a los rayos solares, un 24,7% se expone de 3 ­ 6 horas al día, mientras que el 8,6% registraron el menor tiempo de exposición solar (0 ­ 2 horas). El 75,3% no utiliza bloqueador solar. Conclusión: Los conocimientos y hábitos de exposición solar en los comerciantes ambulantes son de regular a adecuado y los hábitos deficientes.

Objective: To determine the knowledge and habits of solar exposure in street vendors around a Chiclayo market. Methods: A questionnaire were applied to 291 street vendors located around the Chiclayo Model market, who evaluated the habits of sun exposure, photo protection measures, a history of sunburn and skin cancer, as well as knowledge of ultraviolet radiation and sources of information. Results: The ages were, 18-25 (42.3%), 36-54 (38.1%), 55 -78 (19.6%). At the educational level, 13.1% have a complete primary, 32.6% have a complete secondary and 8.2% have a complete superior. At the time of the study, 71.9% had been working as street vendors for more than 3 years. The phototypes of the participants were phototype I (0.3%), phototype II (4.5%), phototype III (24.7%), phototype IV (48.8%), phototype V (19.6%) , phototype VI (2.15). 90 ± 3.5% recognize that it causes skin cancer, 53.6% acknowledge that a characteristic of skin aging by radiation is spots and warts, 56% answered that solar radiation causes cataracts, 52.92% He replied that white-skinned people are more sensitive to the sun's rays. 48.5% of them declared that they were exposed to sunlight for more than 6 hours, 24.7% were exposed to 3-6 hours a day, while 8.6% had the shortest time of sun exposure (0 - 2 hours). 75.3% do not use sunscreen. Conclusion: The knowledge and habits of sun exposure in street traders are from fair to adequate and poor habits.

Efeito do uso de dispositivos auxiliares na precisão do retratamento de facetas diretas / Effect of the use of auxiliary devices on the accuracy of retreatment of direct veneers

A remoção de facetas de resina composta quando o retratamento se faz necessário representa um desafio ao clínico no sentido de preservação do remanescente dental. Sendo assim, o objetivo deste estudo foi avaliar dispositivos auxiliares na precisão dos retratamentos de facetas diretas, por meio de escaneamento digital. Setenta e cinco espécimes de dente bovino (10 x 8 mm ­ cor A1) foram selecionados, e então foi realizado o escaneamento inicial (T0). Em seguida, os espécimes foram preparados para faceta de resina composta e novamente escaneados (T1) para verificação da padronização dos preparos. As superfícies dentárias foram então restauradas com sistema adesivo e resina composta. Os espécimes foram divididos em 5 grupos (n=15): remoção sem dispositivo auxiliar (CN ­ grupo controle), remoção com alta rotação com LED branco (AL), remoção com alta rotação com luz ultra-violeta (UV), remoção com motor elétrico e multiplicadora 1/5 (MT) e remoção com uso de lupa de aumento 2,5x (MN). A remoção das facetas e o re-preparo dos espécimes foi feito por outro operador, sendo então realizado um novo escaneamento (T2). A alteração volumétrica entre T2 e T1, assim como, as áreas de desgaste dentário e/ou presença de resíduos de resina composta foram avaliados. A média entre desgaste e presença de resíduos entre T2 e T1 foi também realizada. Os dados foram submetidos aos testes estatísticos de Kruskal-Wallis e pós teste de Dunn ao nível de significância de 5%. Não foi encontrada diferença estatística entre os grupos entre T1 e T0, com uma média de desgaste de 0,28 mm (± 0,07), p ≥ 0.05. Somente houve diferença entre os grupos para as análises referentes às áreas de desgaste e de presença de resíduos (p ≤ 0,05). Ocorreu maiores áreas de desgaste para o grupo MN, sendo estatisticamente superior aos grupos CN e MT (p≤ 0,05). O oposto ocorreu para áreas de resíduos, sendo que o grupo MN apresentou as menores áreas de resíduos, sendo estatisticamente inferior aos grupos CN e MT (p≤ 0,05). Considerando a média entre desgaste e resíduos, ocorreu um desgaste adicional após o re-preparo, indepedente do grupo (p≥ 0,05). Apesar do uso de lupa odontológica ser mais efetivo para remoção da resina composta durante o retratamento de faceta direta, este proporciona maior desgaste da estrutura dentária. A similaridade da fluorescência entre a resina composta e o substrato dentário minimizou os benefícios do dispositivo com luz UV(AU)

The removal of direct composite veneers when the retreatment is necessary represents a challenge to the clinician in the sense of dental preservation. Thus, the aim of this study was to evaluate auxiliary devices, in the precision of direct composite veneers retreatments, through digital scanning. Seventy-five bovine tooth specimens (10 x 8 mm - A1 shade) were selected and the initial scanning (T0) was performed. Then, the specimens were prepared for direct composite veneer and rescanned (T1) to verify the standardization of the preparations. The dental surfaces were then restored with adhesive system and composite resin. The specimens were divided into 5 groups (n=15): removal without auxiliary device (CN - control group), removal with a hand piece with a white LED (WL), removal with a hand piece with an UV light source (UV), removal with electric motor and multiplier 1/5 hand piece (MT); and removal with the use of a 2.5x dental loupe (MN). The removal of the restorations and the re-preparation of the specimens were done by another operator, and a new scanning (T2) was performed. The volumetric change between T2 and T1, as well as the areas of additional dental wear and presence of composite resin residues were evaluated. The mean considering additional wear and the presence of residues between T2 and T1 were also performed. The data were submitted to Kruskal-Wallis and Dunn's as post-test, at significance level of 5%. No statistical difference among the groups were found between T1 and T0 with a wear mean of 0.28 mm (±0.07), p≥ 0.05. There were only statistical differences between the groups for the analyses related to the areas of wear and presence of residues (p≤ 0.05). There were greater areas of wear for MN group, being statistically superior to CN and MT groups (p≤ 0.05). The opposite occurred for areas of presence of residues, with the MN group presenting smaller areas of residues, being statistically lower than the CN and MT groups (p≤ 0.05). Considering the average between wear and residues, additional wear occurred after re-preparation, regardless of the group (p≥ 0.05). Although the use of dental loupe is more effective for removal of composite resin during the retreatment of direct composite veneers, it provides greater wear of the dental structure. The fluorescence similarity between the composite resin and the dental substrate minimized the benefits of UV light device(AU)

Distinctive bone regeneration of calvarial defects using biphasic calcium phosphate supplemented ultraviolet-crosslinked collagen membrane

PURPOSE: To overcome several drawbacks of chemically-crosslinked collagen membranes, modification processes such as ultraviolet (UV) crosslinking and the addition of biphasic calcium phosphate (BCP) to collagen membranes have been introduced. This study evaluated the efficacy and biocompatibility of BCP-supplemented UV-crosslinked collagen membrane for guided bone regeneration (GBR) in a rabbit calvarial model.METHODS: Four circular bone defects (diameter, 8 mm) were created in the calvarium of 10 rabbits. Each defect was randomly allocated to one of the following groups: 1) the sham control group (spontaneous healing); 2) the M group (defect coverage with a BCP-supplemented UV-crosslinked collagen membrane and no graft material); 3) the BG (defects filled with BCP particles without membrane coverage); and 4) the BG+M group (defects filled with BCP particles and covered with a BCP-supplemented UV-crosslinked collagen membrane in a conventional GBR procedure). At 2 and 8 weeks, rabbits were sacrificed, and experimental defects were investigated histologically and by micro-computed tomography (micro-CT).RESULTS: In both micro-CT and histometric analyses, the BG and BG+M groups at both 2 and 8 weeks showed significantly higher new bone formation than the control group. On micro-CT, the new bone volume of the BG+M group (48.39±5.47 mm3) was larger than that of the BG group (38.71±2.24 mm3, P=0.032) at 8 weeks. Histologically, greater new bone area was observed in the BG+M group than in the BG or M groups. BCP-supplemented UV-crosslinked collagen membrane did not cause an abnormal cellular reaction and was stable until 8 weeks.CONCLUSIONS: Enhanced new bone formation in GBR can be achieved by simultaneously using bone graft material and a BCP-supplemented UV-crosslinked collagen membrane, which showed high biocompatibility and resistance to degradation, making it a biocompatible alternative to chemically-crosslinked collagen membranes.