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1.
Rev. bras. oftalmol ; 81: e0055, 2022. tab, graf
Article in Portuguese | LILACS | ID: biblio-1394862

ABSTRACT

RESUMO Objetivo Analisar o perfil clínico de pacientes portadores de neoplasias escamosas da superfície ocular. Métodos Foram avaliados os principais fatores de risco envolvidos na gênese das neoplasias escamosas da superfície ocular, as características clínicas dos pacientes e os hábitos comportamentais associados. Foram incluídos neste trabalho de coorte histórica 80 pacientes com diagnóstico anatomopatológico de neoplasia escamosa da superfície ocular atendidos entre os anos de 2010 e 2020 em um hospital referência em oculoplástica e segmento anterior de Santa Catarina. Os dados clínicos e desfechos foram avaliados por meio da análise de prontuário e entrevista, sendo posteriormente tabulados no Excel e submetidos à analise estatística por meio do software Statistical Pakage for the Social Sciences, versão 16. Resultados Foi observado que 73,8% (n=59) eram do sexo masculino. A média de idade da amostra foi de 62 anos. Quanto ao fototipo de pele, de acordo com a escala de Fitzpatrick, constatou-se que a maioria apresentou os fototipos 1 e 2 (22; 27,5% e 44; 55%, respectivamente). Em relação à exposição ocupacional ao sol/radiação, 48% (n=60) apresentaram história de exposição ocupacional, sendo que, destes, 28 pacientes trabalhavam no setor de agricultura. Dos pacientes da amostra, 33 (41,2%) apresentavam histórico pessoal de neoplasias de pele, sendo que, destes, três apresentavam diagnóstico de xeroderma pigmentoso. Quanto ao hábito de uso de fatores de proteção solar, 61% (n=49) da amostra negou o hábito. Foi evidenciada associação estatisticamente significativa entre o hábito de usar fatores de proteção solar e histórico pessoal de neoplasias de pele. Em relação ao tipo de neoplasia escamosa, a maioria dos pacientes (72; 90%) apresentou diagnóstico anatomopatológico de carcinoma espinocelular ocular. Conclusão O perfil clínico epidemiológico dos pacientes portadores de neoplasias escamosas da superfície ocular neste estudo, predominantemente de carcinoma espinoceular ocular, foi de homens, idosos, de pele clara (fototipo 2) e com histórico importante de exposição aos raios solares ultravioleta A e B. Comorbidades imunodepressoras (HIV e transplante de órgão sólido) e doenças dermatológicas (albinismo e xeroderma pigmentoso) associaram-se ao aparecimento das neoplasias escamosas da superfície ocular em idade mais precoce. Em pacientes com histórico pessoal prévio de neoplasias de pele, foi evidenciado o hábito de uso de fatores de protetor solar mais presente em relação aos demais.


ABSTRACT Objective To analyze the clinical profile of patients with ocular surface squamous neoplasms (OSSN). Methods The main risk factors involved in the genesis of the ocular surface squamous neoplasms, the clinical features, and the behavioral habits associated were evaluated. This historical cohort study included 80 patients with anatomopathological diagnosis of OSSN who were treated between 2010-2020 at a reference hospital in oculoplastic and anterior segment in Santa Catarina. The clinical data and outcomes were evalated through the analysis of medical records and interviews, being later tabulated in Excel and analyzed using the SPSS 16 software. Results Regarding the clinical profile of the patients in the sample, 73.8% (n = 59) were male. The mean age of the sample was 62 years old. As for the skin phototype, according to the Fitzpatrick scale, most of the sample presented the phototype 1 and 2 (27.5% n = 22; and 55% n = 44 respectively). Regarding occupational exposure to the sun / radiation, 48% (n = 60) had history of occupational exposure, and of these, 28 patients worked in the agricultural area. Of the patients of the sample, 33 (41.2%) had a personal history of skin neoplasms, and of these, 3 had diagnosis of xeroderma pigmentosum. As for the habit of using sun protection factors, 61% (n = 49) of the sample denied the habit. A statistically significant association was evidenced between the habit of using sun protection factors and people's history of skin cancer. Regarding the type of squamous neoplasia, most patients in the 90% sample (n = 72) had an anatomopathological diagnosis of ocular squamous cell carcinoma. Conclusion The clinical epidemiological profile of patients with OSSN in this study, predominantly ocular squamous cell carcinoma, was men, elderly, fair-skinned (phototype 2) and with an important history of exposure to UVA and UVB rays. Immunosuppressive comorbidities (HIV, solid organ transplant) and dermatological diseases (albinism, xeroderma pigmentosum) are associated with the appearance of OSSN at an early age. In patients with a previous personal history of skin neoplasms, the habit of using sunscreen factors was more present than in the other patients.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Skin Neoplasms/epidemiology , Carcinoma, Squamous Cell/epidemiology , Conjunctival Neoplasms/epidemiology , Eye Neoplasms/epidemiology , Skin Neoplasms/pathology , Sunlight/adverse effects , Sunscreening Agents , Ultraviolet Rays/adverse effects , Carcinoma, Squamous Cell/pathology , Comorbidity , Surveys and Questionnaires , Risk Factors , Cohort Studies , Occupational Exposure , Conjunctival Neoplasms/pathology , Solar Radiation , Environmental Exposure , Eye Neoplasms/pathology , Sun Protection Factor/statistics & numerical data
2.
São Paulo; s.n; s.n; 2022. 59 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-1415044

ABSTRACT

Na área da saúde pública, as doenças provocadas pela radiação solar têm ganho grande destaque, por serem cada vez mais comuns. Dentre as principais formas de prevenção a utilização de filtros solares são as mais comuns e de fácil acesso. Os filtros utilizados atuam por sua capacidade de refletir, absorver ou dispersar os raios solares ultravioletas (UV). A aplicação de métodos teóricos tornou-se indispensável no auxílio do planejamento de novos compostos com função terapêutica, em estudos de suas diferentes propriedades, buscando gerar, manipular e analisar representações realistas de estruturas moleculares obtidas a partir de cálculos de propriedades físico-químicas por meio da química computacional. Neste estudo, foram selecionados compostos naturais de origem vegetal (3-O-metilquercetina, ácido gálico, aloína, catequina, quercetina e resveratrol), os quais são descritos com propriedades fotoprotetoras, para os quais se aplicou métodos computacionais para predição dos espectros de absorção, por meio do método TD-DFT (Teoria funcional da densidade dependente do tempo). Foram avaliadas as principais transições eletrônicas dos compostos estudados e se as diferenças de energia HOMO e LUMO para os compostos que absorvem na faixa UV compreendem na UVA (320400 nm, 3.103.87 eV), UVB (290320 nm, 3.874.27 eV) ou na UVC (100290 nm, 4.2712.4 eV). Realizou-se a validação experimental para o método aplicado para o EMC, quercetina e resveratrol, demonstrando a eficácia. Após os estudos realizados concluímos que o resveratrol, teoricamente é um ótimo candidato a fotoprotetor. O estudo ofereceu informações relevantes sobre o poder de predição in silico para fotoprotetores, e se utilizado pode contribuir diminuindo de tempo e custos em pesquisas para desenvolver fármacos


In the area of public health, diseases caused by solar radiation have gained great prominence, as they are increasingly common. Among the main ways to prevent the use of sunscreens are the most common and easily accessible. The filters used act by their ability to reflect, absorb or scatter the sun's ultraviolet (UV) rays. The application of theoretical methods has become indispensable in helping to plan new compounds with therapeutic function, in studies of their different properties, seeking to generate, manipulate and analyze realistic representations of molecular structures obtained from calculations of physicochemical properties through computational chemistry. In this study, natural compounds of plant origin (3-O-methylquercetin, gallic acid, aloin, catechin, quercetin, and resveratrol) were selected, which are described with photoprotective properties, for which computational methods were applied to predict the absorption spectra, using the TD-DFT (Time-Dependent Density Functional Theory) method. The main electronic transitions of the studied compounds were evaluated and whether the differences in HOMO and LUMO energy for compounds that absorb in the UV range comprise UVA (320400 nm, 3.103.87 eV), UVB (290 320 nm, 3.87 4.27 eV) or UVC (100290 nm, 4.2712.4 eV). Experimental validation was carried out for the method applied for CME, quercetin, and resveratrol, demonstrating its effectiveness. After the studies carried out, we concluded that resveratrol, theoretically, is an excellent candidate for sunscreen. The study provided relevant information about the in silico predictive power for photoprotectors, and if used, it can contribute to reducing time and costs in research to develop drugs


Subject(s)
Sunscreening Agents/analysis , Biological Products/adverse effects , Pharmaceutical Preparations/analysis , Ultraviolet Filters , Sun Protection Factor/instrumentation , Ultraviolet Rays/adverse effects , Molecular Structure , Solar Radiation , Density Functional Theory
3.
São Paulo; s.n; s.n; 2022. 172 p. tab, graf.
Thesis in English | LILACS | ID: biblio-1378625

ABSTRACT

The solar ultraviolet (UV) radiation that reaches the Earth is composed of 95% of UVA (320 to 400 nm) and 5% of UVB (280 to 320 nm) radiation. UVB is carcinogenic, generating potentially mutagenic DNA lesions. The solar UVA radiation also causes DNA damage, but this fact does not fully account for its biological impact. UVA is absorbed by non-DNA cellular chromophores, generating reactive oxygen species such as singlet oxygen. Knowing the proteome mediates stress responses in cells, here we investigated the cellular effects of a non-cytotoxic dose of UVA radiation, equivalent to about 20 minutes of midday sun exposure, on the proteome of human keratinocytes. Using a combination of mass spectrometry-based proteomics, bioinformatics, and conventional biochemical assays, we analyzed two aspects of UVA-induced stress: spatial remodeling of the proteome in subcellular compartments 30 minutes after stress and long-term changes in protein levels and secretion (24 hours and 7 days postirradiation). In the first part of this thesis, we quantified and assigned subcellular localization for over 3000 proteins, of which about 600 potentially redistribute upon UVA exposure. Protein redistributions were accompanied by redox modulations, mitochondrial fragmentation and DNA damage. In the second part of the work, our results showed that primary human keratinocytes enter senescence upon exposure to a single dose of UVA, mounting antioxidant and inflammatory responses. Cells under UVA-induced senescence further elicit paracrine responses in neighboring premalignant HaCaT epithelial cells via inflammatory mediators. Altogether, these results reiterate the role of UVA radiation as a potent metabolic stressor in the skin


A radiação ultravioleta (UV) solar que atinge a superfície terrestre é composta por 95% de radiação UVA (320 a 400 nm) e 5% de radiação UVB (280 a 320 nm). A radiação UVB é carcinogênica e gera lesões potencialmente mutagênicas no DNA. A radiação UVA solar também gera danos no DNA, mas a genotoxicidade dessa radiação não explica inteiramente o seu impacto biológico. Atualmente, sabe-se que a radiação UVA é absorvida por cromóforos celulares, gerando espécies reativas de oxigênio, como o oxigênio singlete. Sabendo que o proteoma é um mediador de respostas ao estresse celular, nós investigamos os efeitos celulares de uma dose não-citotóxica de radiação UVA, equivalente a cerca de 20 minutos de exposição ao sol, no proteoma de queratinócitos humanos. Utilizando espectrometria de massas, bioinformática e ensaios bioquímicos convencionais, nós analisamos dois aspectos do estresse induzido por radiação UVA: o remodelamento espacial do proteoma 30 minutos depois do estresse e alterações nos níveis e na secreção de proteínas no longo prazo (24 horas e 7 dias depois da irradiação). Na primeira parte desta tese, nós quantificamos e atribuímos classificações de localização subcelular a mais de 3000 proteínas. Dentre essas proteínas, 600 tem potencialmente a sua distribuição subcelular alterada em resposta à radiação. As redistribuições subcelulares são acompanhadas de modulações redox, fragmentação mitocondrial e danos no DNA. Na segunda parte da tese, os nossos resultados mostraram que queratinócitos humanos primários entram em senescência sob exposição a uma única dose de radiação UVA, montando respostas antioxidantes e pró-inflamatórias. Células sob senescência induzida por UVA, por sua vez, desencadeiam respostas parácrinas em queratinócitos pré-tumorais (células HaCaT) por meio de mediadores inflamatórios. Em conjunto, esses resultados reiteram o papel da radiação UVA como um potente estressor metabólico em células da pele


Subject(s)
Skin , Ultraviolet Rays/adverse effects , Keratinocytes/chemistry , Proteomics/classification , Radiation Dosage , Mass Spectrometry/methods , DNA , Epithelial Cells/classification , Genotoxicity/adverse effects , HaCaT Cells/classification , Antioxidants/adverse effects
4.
Braz. J. Pharm. Sci. (Online) ; 58: e18744, 2022. tab, graf
Article in English | LILACS | ID: biblio-1374554

ABSTRACT

Abstract The continuous prolonged exposures of sun light especially the ultra violet (UV) radiation present in it, cause not only the risk of skin cancer but also it may cause premature skin aging, photodermatoses and actinic keratoses. Flavonoids (including Flavane, Flavanone, Flavone, Flavonol, Isoflavone, Neoflavone etc.) having potent antioxidant activity, used as topical applications for protection against UV induced skin damages as well as for skin care. Most commonly used flavonoid is quercetin (Flavonol), which is present in fruits, vegetables, and herbs. We aim to review the research focused on development of different novel formulations to treat UV radiations induced skin diseases. In this review, several formulations of flavonoid quercetin were discussed and their outcomes were compiled and compared in context to solubility, stability and efficiency of application. On the basis this comparative analysis we have concluded that three formulations, namely glycerosomes, nanostructured lipid carriers and deformable liposomes hold good applications for future aspects for topical delivery of quercetin. These formulations showed enhanced stability, increased quercetin accumulation in different skin layers, facilitated drug permeation in skin and long-lasting drug release.


Subject(s)
Quercetin/analysis , Skin/injuries , Skin Diseases/drug therapy , Skin Neoplasms/pathology , Ultraviolet Rays/adverse effects , Phytochemicals/analysis , Flavonoids/adverse effects , Pharmaceutical Preparations/analysis , Keratosis, Actinic/pathology , Protective Factors , Antioxidants/classification
5.
Biomedical and Environmental Sciences ; (12): 101-109, 2021.
Article in English | WPRIM | ID: wpr-878326

ABSTRACT

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.


Subject(s)
Female , Humans , Male , Blindness/etiology , Cataract/etiology , Global Burden of Disease/statistics & numerical data , Quality-Adjusted Life Years , Social Class , Socioeconomic Factors , Ultraviolet Rays/adverse effects
6.
São Paulo; s.n; s.n; 2021. 60 p. tab, graf.
Thesis in English | LILACS | ID: biblio-1415547

ABSTRACT

Unprotected chronic exposure to ultraviolet radiation generates many harmful effects to human skin and UV filters are essential to health, however, traditional sunscreens do not provide enough protection against cutaneous oxidative stress, a process amplified by UV radiation. Therefore, is been proposed the development of multifunctional photoprotective formulations, acting in the absorption/reflection of UV radiation and assisting in cutaneous homeostasis. In the present study, ferulic acid is used in conjunction with two sunscreens, bemotrizinol and ethylhexyl triazone, for the determination of biosafety and efficacy methods, using techniques that better elucidate the effects of ferulic acid. Skin permeation assays were performed by applying a formulation containing the three substances in the stratum corneum of volunteers, which were removed by the tape stripping method (ex vivo) with follow quantification by high performance liquid chromatography (HPLC). The test was able to evaluate the penetration depth of the substances, characterizing them. In addition, the simultaneous quantification of the three substances was performed by a single and fast method, facilitating their analysis and improving the technique. Also, TBARS (thiobarbituric acid reactive substances) assays were performed in stratum corneum removed by tape stripping (ex vivo), evaluating the potential of cutaneous lipid peroxidation, with or without ferulic acid. To date, it is the first time that TBARS method is used to characterize the stratum corneum (ex vivo) and quantified by HPLC. The protocol developed may aid in the efficacy of antioxidant agents in studies aimed at elucidating the level of lipid peroxidation caused by drugs and cosmetics, and even in carrying out baseline studies characterizing different ethnicities and genders. As last, an anti-inflammatory in vivo assay with Laser Doppler flowmetry equipment was used to compare the sunscreen formulation with or without ferulic acid. Data indicated that the antioxidant reduced the angular coefficient of the perfusion units, mitigating the inflammatory effects. Furthermore, a significant difference was found between the genders, suggesting a more pronounced inflammatory reaction in women. Ferulic acid proved to be a valuable resource, besides being safe and raise the SPF of sunscreens, it also mitigates the effects of inflammation


A exposição crônica desprotegida à radiação ultravioleta (UV) contribui para o desenvolvimento de câncer de pele e os filtros solares são relevantes para evitar tais efeitos prejudiciais, porém, os protetores solares tradicionais não geram proteção suficiente contra o estresse oxidativo cutâneo. Logo, espera-se o desenvolvimento de formulações fotoprotetoras multifuncionais, atuando não somente na absorção e/ou reflexão da radiação UV, mas, também, auxiliando na homeostase cutânea, com presença de agentes antioxidantes. No presente estudo foi utilizado o ácido ferúlico conjuntamente com dois filtros solares, o bemotrizinol e a triazona de octila, para determinação de métodos de segurança e eficácia, utilizando técnicas que melhor elucidem e comprovem os efeitos do ácido ferúlico. Foram realizados ensaios de permeação cutânea pela aplicação tópica de formulação contendo as três substâncias em voluntários, sendo o estrato córneo retirado pelo método de tape stripping (ex vivo) com subsequente quantificação por cromatografia líquida de alta eficiência (CLAE). O ensaio pôde avaliar a profundidade de penetração das substâncias, caracterizando-as. Ademais, a quantificação simultânea das três substâncias foi efetuada por método único e rápido, facilitando análise com aprimoramento da técnica. Em adição, foi realizado ensaios de TBARS (substâncias reativas ao ácido tiobarbitúrico) em estrato córneo removido por tape stripping (ex vivo), para avaliar o potencial de peroxidação lipídica cutânea, contendo ou não o ácido ferúlico. Até o presente momento, é a primeira vez que o método TBARS é utilizado para caracterização do estrato córneo (ex vivo) e quantificada por CLAE. O protocolo desenvolvido pode auxiliar na eficácia de agentes antioxidantes, em estudos que visam elucidar o nível de peroxidação lipídica causada por medicamentos e cosméticos e, até mesmo, na realização de estudos de base, caracterizando etnias e gêneros. Ademais, um ensaio anti-inflamatório in vivo com equipamento de fluxometria Laser Doppler foi utilizado para comparar a formulação fotoprotetora com ou sem ácido ferúlico. Os dados indicaram que o antioxidante reduziu o coeficiente angular das unidades de perfusão, mitigando os efeitos inflamatórios. Ainda, foi identificada diferença entre os gêneros, sugerindo reação inflamatória mais pronunciada em mulheres. O ácido ferúlico provou ser um recurso valioso, além de ser seguro e elevar o FPS dos fotoprotetores, também atenuando os efeitos da inflamação


Subject(s)
Sunscreening Agents/analysis , Efficacy , Protective Factors , Anti-Inflammatory Agents/analysis , Antioxidants/administration & dosage , Radiation , Skin Neoplasms/classification , Ultraviolet Rays/adverse effects , Pharmaceutical Preparations/analysis , Chromatography, High Pressure Liquid/methods , Thiobarbituric Acid Reactive Substances/pharmacology , Laser-Doppler Flowmetry/methods , Oxidative Stress/drug effects , Cosmetics/classification , Diagnosis
8.
Rev. ciênc. farm. básica apl ; 41: [14], 01/01/2020. tab, ilus, graf
Article in English | LILACS | ID: biblio-1128573

ABSTRACT

Neem tree (Azadirachta indica A. Juss. fam. Meliaceae) has been extensively employed to combat diverse pathologies. Moreover, it has been described that its leaf extract present anticarcinogenic action. Thus, the neem extract (NE) chemical and antioxidant properties was evaluated, and also, the capacity of two dermatological formulations incorporated with neem extract (F1 and F2) to avoid oxidative UVB-induced skin injury in hairless mice. NE constituents were investigated and free radical scavenging ability were determined by different methods in vitro. Skin from mice treated with F1 and F2 and submitted to UVB radiation were tested for different parameters of inflammation and oxidative injury. Results show that the NE polyphenol and flavonoid content were 135.30 and 37.12mg/g, respectively. High performance liquid chromatography (HPLC) results demonstrated the existence of azarachtin, rutin, ursolic acid and tannic acid. NE presented scavenging ability by ABTS radical, ferric-reducing antioxidant power (FRAP), inhibition of lipid peroxidation and iron chelation. In vivo, it was observed that mice treated with F1 and F2 showed amelioration of the inflammation by reducing UVB induced skin edema. However, only samples from animals treated with F1 had lower neutrophil recruitment (measured by myeloperoxidase activity), and returning the oxidative status to baseline levels in parameters such as reduced glutathione level, ferric reducing ability (FRAP), and scavenging of free radical (ABTS). Concluding, NE demonstrated a good antioxidant property in vitro, and the data suggest the use of NE added F1 to prevent skin damage caused by UVB irradiation.(AU)


Subject(s)
Animals , Male , Female , Mice , Ultraviolet Rays/adverse effects , Oxidative Stress/drug effects , Azadirachta , Antioxidants/radiation effects , Administration, Cutaneous , Chromatography, High Pressure Liquid/methods , Mice
9.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 934-940, 2020.
Article in English | WPRIM | ID: wpr-881039

ABSTRACT

A contributory role of oxidative stress and protection by antioxidant nutrients have been suspected in cataract formation. Ganoderic acid A (GAA), an effective lanostane triterpene, is widely reported as an antioxidant. The aim of this study is to investigate the potential effects of GAA on cataract formation. After lens epithelial cells (LECs) were exposed to UVB radiation for different periods, cell viability, apoptosis-related protein levels, malondialdehyde (MDA) and superoxide dismutase (SOD) activities were monitored. We found that cell viability, the Bcl-2/Bax ratio and SOD activity were increased, while Cleaved caspase-3 levels and MDA activity were decreased compared with those in UVB-impaired LECs after GAA treated. Furthermore, GAA activated PI3K/AKT in UVB-impaired LECs and effectively delayed the occurrence of lens opacity in vitro. In conclusion, these findings demonstrated that GAA exhibited protective functions in SRA01/04 cells and rat lenses against UVB-evoked impairment through elevating cell viability and antioxidant activity, inhibiting cell apoptosis, activating the PI3K/AKT pathway and delaying lens opacity.


Subject(s)
Animals , Humans , Rats , Apoptosis , Cataract/prevention & control , Cell Line , Cell Survival , Epithelial Cells/radiation effects , Heptanoic Acids/pharmacology , Lanosterol/pharmacology , Lens, Crystalline/radiation effects , Malondialdehyde/metabolism , Superoxide Dismutase/metabolism , Ultraviolet Rays/adverse effects
10.
Rev. chil. dermatol ; 36(1): 4-10, 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1381335

ABSTRACT

INTRODUCCIÓN: La sobreexposición a la radiación ultravioleta (RUV) es un factor de riesgo importante para el desarrollo de cáncer de piel (CP). Aquellos trabajadores que realizan labores al aire libre, como los pescadores, son un grupo de riesgo, por lo que es importante saber si tienen los conocimientos y realizan las conductas que les permitan protegerse de la RUV. OBJETIVO: Evaluar en un grupo de pescadores el conocimiento respecto a los riesgos de la exposición solar y sus conductas respecto a medidas de protección solar. MATERIAL Y MÉTODOS: Los datos fueron obtenidos por encuestas a 133 pescadores. Se obtuvieron antecedentes sociodemográficos y se aplicó un cuestionario de 11 preguntas para evaluar conocimiento sobre riesgos de la RUV y conductas de fotoprotección. RESULTADOS: La cohorte incluyó a 133 pescadores, todos fueron hombres con edad promedio de 48 +/- 11,2 años. Un 86% de los pescadores conocía la relación entre exposición solar/CP. En cuanto al uso de filtro solar (FS), un 54,8% de los trabajadores reportó nunca haberlo utilizado y un 41% lo hacía solo una vez al día. Los pescadores con escolaridad incompleta presentan 2,6 veces menor probabilidad de utilizar FS (OR 2.6; p<0.05). Además, aquellos con conocimiento de la relación RUV y fotoenvejecimiento, presentaban 3,75 veces más probabilidad de utilizar FS (OR 3.75) (p<0.05). CONCLUSIÓN: Este primer estudio sobre protección solar en pescadores muestra que la mayoría están en conocimiento de los riesgos a la salud. Sin embargo, no utilizan las medidas de protección recomendadas y aquellos que las utilizan, no lo hacen de la manera adecuada.


INTRODUCTION: Overexposure to ultraviolet radiation (UVR) is the main risk factor for the development of skin cancer (SC). Outdoor workers, such as fishermen are a risk group. Therefore, it is important to study if they have the knowledge towards sun exposure and also to know their solar protection behaviors. OBJETIVE: To evaluate in a group of fishermen if they have the knowledge about the risks of solar exposure and their behavior regarding sun protection measures. MATERIALS y METHODS: Data was obtained from a survey applied to 133 fishermen. Collected information included sociodemographic characteristics and 11 questions about knowledge and their sun protection measures. RESULTS: The cohort included 133 fishermen, all were male with an age average of 48 +/- 11,2 years. 86% knew about the relation between solar exposure and skin cancer. When asked about sunscreen use, 54.8% declared they never used it and 41,0% did only once a day. The fishermen who had incomplete secondary school studies were less likely to use sunscreen (OR 2.6) (p<0.05). Those who had knowledge of the relation between UVR and aging were 3,75 times more likely to use sunscreen. CONCLUSION: This is the first study about solar protection knowledge and photoprotection measures upon fishermen, performed in Chile. Most fishermen were aware of the health risks. However, they do not use the recommended protection measures, and those who use them, do not do it properly


Subject(s)
Humans , Male , Adult , Middle Aged , Aged , Young Adult , Sunscreening Agents/administration & dosage , Health Knowledge, Attitudes, Practice , Fisheries , Occupational Diseases/prevention & control , Skin Neoplasms/prevention & control , Ultraviolet Rays/adverse effects , Occupational Risks , Skin Aging/radiation effects , Chile , Cross-Sectional Studies , Surveys and Questionnaires , Occupational Exposure
11.
An. bras. dermatol ; 94(5): 567-573, Sept.-Oct. 2019. tab
Article in English | LILACS | ID: biblio-1054861

ABSTRACT

Abstract Background One of the main prevention methods against skin cancer is the use of sunscreen; however, incidence of this disease has not declined despite prevention campaigns. Objective Investigate the prevalence of non-use of sunscreen and its associated factors. Method A population-based cross-sectional study with individuals aged 18 years or over living in the urban area. Conducted between April and July of 2016. Participants were interviewed about socioeconomic, demographic, and behavioral questions. Non-use of sunscreen was considered as the outcome. For multivariate analysis, Poisson regression with robust adjustment for variance was used. Results Among the 1300 participants, prevalence of non-use of sunscreen was 38.2% (95% CI: 34.6-41.8). The variables independently associated with the outcome were male sex, older age, brown or black skin color, lower income, fewer years of education, no physical activity in leisure time, no medical consultations in the last year, and self-perception of health as regular or poor. Study limitations The prevalence may be underestimated by reports of more use of sunscreen than actually used, which could increase the figure in the outcome. Conclusion It was estimated that about four out of ten adults and elderly do not use sunscreen in this sample. Prevention strategies are needed to advance health policy and ensure that sun protection options are easily accessible.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Sunscreening Agents/therapeutic use , Ultraviolet Rays/adverse effects , Radiation Exposure/prevention & control , Skin Neoplasms/prevention & control , Brazil , Cross-Sectional Studies , Surveys and Questionnaires , Risk Factors , Sex Distribution , Age Distribution , Diagnostic Self Evaluation , Health Risk Behaviors
12.
An. bras. dermatol ; 94(5): 503-520, Sept.-Oct. 2019. tab, graf
Article in English | LILACS | ID: biblio-1054862

ABSTRACT

Abstract Oculocutaneous albinism is an autosomal recessive disease caused by the complete absence or decrease of melanin biosynthesis in melanocytes. Due to the reduction or absence of melanin, albinos are highly susceptible to the harmful effects of ultraviolet radiation and are at increased risk of actinic damage and skin cancer. In Brazil, as in other parts of the world, albinism remains a little known disorder, both in relation to epidemiological data and to phenotypic and genotypic variation. In several regions of the country, individuals with albinism have no access to resources or specialized medical care, and are often neglected and deprived of social inclusion. Brazil is a tropical country, with a high incidence of solar radiation during the year nationwide. Consequently, actinic damage and skin cancer occur early and have a high incidence in this population, often leading to premature death. Skin monitoring of these patients and immediate therapeutic interventions have a positive impact in reducing the morbidity and mortality associated with this condition. Health education is important to inform albinos and their families, the general population, educators, medical professionals, and public agencies about the particularities of this genetic condition. The aim of this article is to present a review of the epidemiological, clinical, genetic, and psychosocial characteristics of albinism, with a focus in skin changes caused by this rare pigmentation disorder.


Subject(s)
Humans , Male , Female , Albinism/genetics , Albinism/pathology , Skin Neoplasms/etiology , Skin Neoplasms/physiopathology , Ultraviolet Rays/adverse effects , Brazil/epidemiology , Carcinoma, Basal Cell/etiology , Carcinoma, Basal Cell/pathology , Carcinoma, Squamous Cell/etiology , Carcinoma, Squamous Cell/pathology , Albinism/complications , Albinism/epidemiology , Prevalence , Risk Factors , Keratosis, Actinic/etiology , Keratosis, Actinic/pathology , Melanins/deficiency
13.
An. bras. dermatol ; 94(5): 532-541, Sept.-Oct. 2019. tab, graf
Article in English | LILACS | ID: biblio-1054868

ABSTRACT

Abstract Background The knowledge of general practitioners about photoprotection is unknown. Objectives To develop and validate an instrument to evaluate the knowledge of general practitioners and pediatricians about photoprotection, gauging the knowledge of these professionals. Methods The study followed the steps: (1) Literature identification and item elaboration related to the theme; (2) Content validation; (3) Apparent validation; (4) Construct validation: internal consistency analysis and discriminatory analysis; (5) Reliability analysis. In Step 4, the instrument was applied to 217 general practitioners and pediatricians who worked in the host city of the study; the scores were compared with dermatologists scores. Results The final instrument had 41 items and showed satisfactory internal consistency (Cronbach's alpha = 0.780), satisfactory reproducibility and good test-retest reliability (good-to-excellent kappa statistic in more than 60% of items). The discriminatory analysis registered a mean score of 54.1 points for dermatologists and 31.1 points for generalists and pediatricians, from a total of 82 possible points, representing a statistically significant difference (p < 0.001). Generalists and pediatricians demonstrated an understanding of the relationship between excessive sun exposure and skin cancer, but they revealed lack of technical information necessary for their professional practice. Study limitations The instrument evaluates only knowledge, without evaluating the conduct of the participants. Conclusion The results show that the instrument has good internal consistency and good reproducibility. It could be useful in the identification of general practitioners and pediatricians knowledge gaps on the subject, for the subsequent development of training and educational strategies.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Radiation Protection/methods , Solar Energy , Ultraviolet Rays/adverse effects , Health Knowledge, Attitudes, Practice , Surveys and Questionnaires/standards , General Practitioners/statistics & numerical data , Pediatricians/statistics & numerical data , Skin Neoplasms/prevention & control , Sunscreening Agents/therapeutic use , Brazil , Reproducibility of Results , Statistics, Nonparametric , Radiation Exposure/prevention & control
14.
Arq. bras. med. vet. zootec. (Online) ; 71(4): 1085-1092, jul.-ago. 2019. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1038605

ABSTRACT

A retrospective and cross-sectional study of canine tumors was performed in the capital of State of Mexico from 2002-2016. Since then, 393 tumors were remitted. Descriptive epidemiology was made from all data: breed, age, sex, and tumor features. Then the risk association between cutaneous and non-cutaneous tumors with variables such as sex, breed, and age were analyzed through an exact Fisher test and Odds ratio. In addition, some characteristics of the canine population were studied under a survey. Of all tumors, skin tumors were the most frequent (59.0%). The group of tumors related to ultraviolet radiation was the most common (15.1%). The frequency of tumors in females was 53%, nevertheless, males had more risk to develop cutaneous tumors (OR=1.88, 1.24-2.84) (0.003). The Pure breeds were the most common (82.5%) and the most frequent age range was > 7 years (54.7%). The survey showed that males (53%) and the age range 1-7 years (62.1%) were the most frequent. Conclusions, age, breed, and sex were identified as the major risk factors for tumorigenesis. Likewise, skin tumors were associated with exposure to ultraviolet radiation, probably to the height of the locality (2667mamls).(AU)


Um estudo retrospectivo e transversal dos tumores caninos foi realizado na capital do Estado do México durante o período de 2002-2016. Desde esse período, 393 tumores foram remetidos. Epidemiologia descritiva foi feita com base em todos os dados: raça, idade, sexo e características do tumor. Em seguida, a associação de risco entre tumores cutâneos e não cutâneos com variáveis como sexo, raça e idade foi analisada por meio do teste exato de Fisher e odds ratio. Além disso, algumas características da população canina foram estudadas em uma pesquisa. De todos os tumores, os de pele foram os mais frequentes (59,0%). O grupo de tumores relacionados à radiação ultravioleta foi o mais comum (15,1%). A frequência de tumores no sexo feminino foi de 53%, no entanto os machos apresentaram maior risco de desenvolver tumores cutâneos (OR = 1,88; 1,24-2,84) (0,003). As raças puras foram as mais comuns (82,5%), e a faixa etária mais frequente foi >7 anos (54,7%). A pesquisa mostrou que os machos (53%) e a faixa etária de um a sete anos (62,1%) foram os mais frequentes. Conclusões: idade, raça e sexo foram identificados como os principais fatores de risco para a tumorigênese. Da mesma forma, os tumores cutâneos foram associados à exposição à radiação ultravioleta, provavelmente até a altura da localidade (2667m ANM).(AU)


Subject(s)
Animals , Dogs , Skin Neoplasms/veterinary , Skin Neoplasms/epidemiology , Ultraviolet Rays/adverse effects , Carcinogenesis , Mexico/epidemiology
15.
São Paulo; s.n; s.n; 2019. 57 p. graf, tab.
Thesis in Portuguese | LILACS | ID: biblio-997079

ABSTRACT

O aumento da incidência do câncer de pele está associado à maior exposição à luz solar e a adoção de ações de proteção ao Sol é uma estratégia para minimizar os níveis cumulativos de danos à pele. Os raios ultravioletas (UV), ao alcançarem o tecido cutâneo, podem causar eritema, inflamação, fotoenvelhecimento, formação de rugas e imunossupressão, entre outros, devido à formação de espécies reativas de oxigênio (ERO´s). A formação de ERO´s, como o oxigênio singleto, radical ânion superóxido, peróxido de hidrogênio e radical hidroxil, elevam o risco dos danos foto-oxidativos. O desequilíbrio entre a formação de ERO´s e os mecanismos antioxidantes do organismo desencadeia o estresse oxidativo. Na pele, as ERO´s são as responsáveis pelo dano oxidativo no DNA, proteínas e lipídeos. Identificar e quantificar biomarcadores do estresse oxidativo cutâneo é essencial para a correlação entre os raios UV e seus efeitos. Deve-se isto, em parte, à limitação de métodos para quantificar os parâmetros que são diretamente afetados pela exposição aos raios UV, tais como a peroxidação lipídica. São necessários métodos complementares para avaliação da eficácia de fotoprotetores perante os danos causados por este tipo de estresse. Esta pesquisa projeto compreendeu a avaliação ex vivo da eficácia de filtros solares UVB por meio da quantificação da peroxidação lipídica proveniente do estrato córneo removido por tape stripping. Foram preparados sistemas emulsionados do tipo O/A com os filtros octocrileno, metoxicinamato de octila e salicilato de octila. A caracterização funcional da eficácia fotoprotetora in vitro demonstrou que o filtro octocrileno manteve-se estável, mesmo após exposição solar artificial. Os filtros octocrileno (10% p/p), metoxicinamato de octila (10% p/p) e salicilato de octila (5% p/p) alcançaram, após irradiância, respectivamente, os valores de FPS 5,7 ± 2,1; 4,7 ± 1,5 e 1,0± 0,0. As formulações foram utilizadas na avaliação da eficácia fotoprotetora ex vivo. O método por CLAE, para quantificação da peroxidação lipídica no estrato córneo, possuiu linearidade e demonstrou exatidão e precisão satisfatórias. O estresse pela radiação UV desencadeou a peroxidação lipídica no estrato córneo. Em função do protocolo aplicado, não houve diferenças entre as amostras. A eficácia, com relação à inibição da peroxidação lipídica, foi similar em todas as amostras


The increasing of incidence of skin cancer is associated with greater exposure to sunlight and the adoption of sun protection actions is a strategy to minimize cumulative levels of skin damage. Ultraviolet (UV) rays, when they reach the cutaneous tissue, can cause erythema, inflammation, photoaging, wrinkling and immunosuppression, among other things, due to the formation of reactive oxygen species (ROS). The formation of ROS, such as singlet oxygen, superoxide anion radical, hydrogen peroxide and hydroxyl radical, raise the risk of photooxidative damage. The variation between the formation of ROS and the antioxidant mechanisms of the organism triggers oxidative stress. In the skin, ROS are responsible for oxidative damage in DNA, proteins and lipids. Identifying and quantifying biomarkers of cutaneous oxidative stress is essential for the correlation between UV rays and their effects. This is partially due to the limitation of methods for quantifying parameters that are directly affected by exposure to UV rays, such as lipid peroxidation. Complementary methods are needed to evaluate the effectiveness of photoprotectors because of the damage caused by this type of stress. This research project had the ex vivo evaluation of the efficacy of UVB sunscreens by quantifying the lipid peroxidation from the stratum corneum removed by tape stripping. Emulsified O/A type systems were prepared with the octocrylene, octyl methoxycinnamate and octyl salicylate filters. The functional characterization of photoprotective efficacy in vitro revealed that the octocrylene filter remained stable even after artificial sun exposure. Octocrylene (10% w / w), octyl methoxycinnamate (10% w / w) and octyl salicylate (5% w / w) respectively reached the values of FPS 5.7 ± 2.1; 4.7 ± 1.5 and 1.0 ± 0.0. The formulations were used in the evaluation of ex vivo photoprotective efficacy. The method by HPLC, for quantification of the lipid peroxidation in the stratum corneum, had linearity and demonstrated satisfactory accuracy and precision. UV radiation stress triggered lipid peroxidation in the stratum corneum. Due to the protocol applied, there were no differences between the samples. The efficacy, compared to the inhibition of lipid peroxidation, was similar in all samples


Subject(s)
Ultraviolet Rays/adverse effects , Lipid Peroxidation/radiation effects , Sunscreening Agents/analysis , Thiobarbituric Acid Reactive Substances/pharmacokinetics
16.
São Paulo; s.n; s.n; 2019. 102 p. graf, tab, ilus.
Thesis in English | LILACS | ID: biblio-1023978

ABSTRACT

Ultraviolet radiation (UV) is related to the development of skin cancer and photoaging, also produces free radicals or reactive oxygen species (ROS) that cause premature aging. Therefore, sunscreens with extended UV protection capacity have been studied associated with antioxidant compounds. Different components can be incorporated with the purpose of improving, the photoprotection efficiency, as well as other cosmetic attributes, creating a multifunctional product. Among the compounds, there are some to be used from natural origin that are excellent, because it reduces the side effects and toxicity. Flavonoids are good examples of natural agents, because have demonstrated photoprotective antioxidant action in food and it is also promising for topical use. The aim of this work is to develop photoprotective formulations with quercetin, evaluating potential photoprotective and antioxidant of each formulation through tests already established and described in the literature, with emphasis on in vitro testing of potential photoprotective, antioxidant and security (het-cam); ex vivo antioxidant potential (tape-stripping). The results show us the photoprotective and antioxidant capacity of quercetin and the ideal concentration for this potential, thereby contributing to the synthesis of new molecules and development of new products, concerning stable, safe and effective exposure to solar UV radiation, preventing new incidences of skin cancer and reduction of photoaging


A radiação ultravioleta (UV) está relacionada ao desenvolvimento de câncer de pele e fotoenvelhecimento, também produz radicais livres ou espécies reativas de oxigênio (EROs) que causam o envelhecimento precoce. Portanto, protetores solares com capacidade de proteção UV amplo espectro foram estudados associados a compostos antioxidantes. Diferentes componentes podem ser incorporados com o objetivo de melhorar a eficiência da fotoproteção, assim como outros atributos cosméticos criando um produto multifuncional. Entre os compostos a serem utilizados, de origem natural são excelentes, pois reduzem os efeitos colaterais e a toxicidade. Os flavonóides são bons exemplos de agentes naturais, porque demonstraram ação antioxidante fotoprotetora nos alimentos e também são promissores para uso tópico. O objetivo deste trabalho é desenvolver formulações fotoprotetoras com quercetina, avaliando potenciais fotoprotetores e antioxidantes de cada formulação através de testes já estabelecidos e descritos na literatura com ênfase em ensaios in vitro de potenciais fotoprotetores, antioxidantes e de segurança (het-cam); potencial antioxidante ex vivo (tape-stripping). Os resultados nos mostram a capacidade fotoprotetora e antioxidante da quercetina e a concentração ideal para este potencial, contribuindo para a síntese de novas moléculas e desenvolvimento de novos produtos estáveis, seguros e eficazes em relação à exposição à radiação solar UV, prevenindo novas incidências de câncer de pele e redução do fotoenvelhecimento


Subject(s)
Quercetin/pharmacology , Sunscreening Agents/analysis , Ultraviolet Rays/adverse effects , Flavonoids/agonists , In Vitro Techniques/instrumentation , Skin Aging , Antioxidants/analysis
17.
Estud. interdiscip. envelhec ; 23(3): 159-173, dez. 2018. tab
Article in Portuguese | INDEXPSI, LILACS | ID: biblio-1010382

ABSTRACT

Objetivo: Identificar a presença do envelhecimento precoce de pele em pescadores de Salinópolis/PA. Métodos: A pesquisa foi realizada com 275 pescadores, de 18 a 59 anos, no período de março a maio de 2016, sendo aplicados dois questionários: "Protocolo de Avaliação Facial ­ PAF" e "Hábitos de exposição e fotoproteção solar", ambos modificados pelas pesquisadoras. Resultados: Foi observada prevalência de trabalhadores praianos de 26 a 35 anos (36%), pele parda (70%), fototipo III (64%) e com a presença de fotoenvelhecimento (61%), que se expunham diariamente ao sol (97%), não possuíam cuidados com a pele (91%) e não usavam protetor solar (92%). Os voluntários relataram que não gostavam de aplicar protetor solar (59%) e desconheciam que a radiação ultravioleta causava envelhecimento da pele (60%), manchas na pele (54%) ou câncer (56%). Conclusão: A maioria dos pescadores não utilizavam fotoprotetores e apresentavam fotoenvelhecimento com predisposição a desenvolver câncer de pele. (AU)


Objective: To identify the presence of precocious skin aging in fishermen in Salinópolis/PA. Methods: The research was carried out with 275 fishermen, from 18 to 59 years of age, from March to May 2016. Two questionnaires were applied: "Facial Evaluation Protocol ­ PAF" and "Habits of exposure and solar photoprotection", both modified by the researchers. Results: The prevalence of beach workers from 26 to 35 years of age (36%), of brown skin (70%), phototype III (64%) and photoaging (61%), who were exposed daily to the sun (97%), did not have skin care (91%) and did not use sunscreen (92%). The volunteers reported that they did not like to apply sunscreen (59%) and were unaware that ultraviolet radiation caused skin aging (60%), skin blemishes (54%) or cancer (56%). Conclusion: Most fishermen did not use photoprotectors and presented photoaging with a predisposition to develop skin cancer. (AU)


Subject(s)
Humans , Adolescent , Adult , Middle Aged , Skin Neoplasms/etiology , Sunscreening Agents/administration & dosage , Ultraviolet Rays/adverse effects , Skin Aging/radiation effects , Fisheries , Sunlight/adverse effects , Cross-Sectional Studies
18.
São Paulo; s.n; s.n; 2018. 207 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-913431

ABSTRACT

Filtros orgânicos são amplamente utilizados em formulações fotoprotetoras, com habilidade de absorver radiações ultravioleta (UV). Contudo, parte destes compostos possuem limitações, como: fotoinstabilidade, permeação cutânea e fotossensibilização e entre outros. Este trabalho envolveu a síntese de matriz mesoporosa do tipo SBA-15, encapsulação/incorporação de ρ-metoxicinamato de octila (MCO), benzofenona-3 (BZF-3) e avobenzona (AVO) na SBA-15 para aplicação em formulações fotoprotetoras. Fez-se a determinação da eficácia in vitro dos filtros encapsulados/incorporados combinados a ingrediente cosmético; o preparo de bastão fotoprotetor e determinação eficácia estimada; a avaliação do potencial de irritação ocular dos bastões por HET-CAM - Hen's Egg Test - Chorioallantoic Membrane, e a avaliação da permeação/retenção cutânea e perfil de biodistribuição dos filtros. Para a caracterização dos materiais foram empregadas técnicas físico-químicas e analíticas. As medidas de adsorção/dessorção de N2 mostrou que as amostras dos filtros solares encapsulados/incorporados apresentaram diminuição na área superficial e volume de poro (V), indicando que os filtros solares foram encapsulados/incorporados na superfície e nos poros da SBA-15. Os resultados de Espalhamento de raios X a baixo ângulo evidenciaram que os filtros solares não afetaram a estrutura hexagonal da SBA-15. Por TG/DTG e análise elementar foi possível determinar a quantidade de filtros solares na superfície e nos mesoporos da SBA-15. Enquanto, as curvas DSC e DTA revelaram aumento na estabilidade térmica da AVO e BZF-3, quando encapsulados/incorporados. Os resultados da eficácia fotoprotetora in vitro mostraram que a combinação dos três filtros solares encapsulados/incorporados na SBA-15 promoveram aumento de 52% no fator proteção solar (FPS), enquanto que, na formulação fotoprotetora contendo os três filtros encapsulados/incorporados, o aumento foi de 94%. O ensaio de HET-CAM evidenciou que os bastões contendo SBA-15 e os filtros encapsulados/incorporados não foram irritantes. O ensaio de permeação/retenção cutânea mostrou que o processo de encapsulação/incorporação da BZF-3 promoveu diminuição de sua permeação em todos os tempos de exposição. As quantidades permeadas de AVO e MCO ficaram abaixo do limite de quantificação nos tempos 6 e 12 h, no entanto, no tempo de 24 h foi possível quantificá-los. As quantidades dos filtros solares retidas na pele a partir da formulação contendo os filtros solares encapsulados/incorporados na SBA-15 (F4) foram menores (tempos 6 e 12 h) em comparação à formulação contendo os filtros solares não encapsulados (F3). A investigação da biodistribuição dos filtros solares mostrou que a retenção total na pele, como na derme, foi menor na formulação F4 em comparação à F3. O estudo comparativo entre pele suína e a pele humana mostrou que as quantidades de BZF-3 e AVO permeadas e retidas na pele suína foram superiores do que em relação à humana para ambas as formulações (F4 e FR). Pela técnica de biodistribuição, foi possível determinar que os filtros solares oriundos das formulações F3 e referência (FR) apresentaram maior retenção destes compostos na derme do que em outras camadas da pele. Contudo, observou-se que os filtros encapsulados apresentaram taxa reduzida de retenção na derme


Organic Filters are chemical compounds widely used in sunscreens formulations with the ability to absorb ultraviolet radiation (UV). Despite the effectiveness of these compounds in UV radiation protection, disadvantages related to their photo instability, potential skin permeation and photo sensibility pose significant challenges for improving these products. The aim of this work was to synthesize mesoporous matrix SBA-15, encapsulation/entrapping of octyl methoxycinnamate (OMC), benzophenone-3 (BZF-3) and avobenzone (AVO) into SBA-15 for application in photoprotective formulations. It was accessed in vitro photoprotection efficacy and in vitro photostability assay of encapsulated/entrapped UV filters combined with cosmetic ingredient and photoprotective stick formulations; evaluation of the ocular irritation potential of photoprotective stick formulations by in vitro method HET-CAM - Hen's Egg Test - Chorioallantoic Membrane; evaluation the skin permeation/deposition and biodistribution profile of photoprotective stick formulations. The decrease in the surface area and in mesoporous volume (V) observed in the nitrogen adsorption desorption isotherms of encapsulated/entrapped samples indicated that UV filters were efficiently encapsulated/entrapped into SBA-15. Additionally, SAXS results showed that UV filters did not affected the hexagonal structure of the mesoporous material and that these compounds filled the SBA-15 pores. TG/DTG and elemental analysis were efficient tools to confirm the presence and the quantity of UV filters into SBA-15. DTA and DSC curves of encapsulated/entrapped materials showed that the thermal stability of AVO and BZF-3 were increased. On the other hand, DSC curves of encapsulated/entrapped materials demonstrated that thermal stability of OMC was not increase. The in vitro photoprotective efficacy results demonstrated that the combination of the three sunscreens encapsulated/entrapped into SBA-15 increased 52.0% the SPF values, while the stick formulation containing the UV filters encapsulated/entrapped, the increase was 94.0%. Delivery experiments using porcine skin demonstrated that the encapsulation/entrapping process of UV filters resulted the decreased of BZF-3 permeation and deposition in skin (6 and 12 hours). The cutaneous biodistribution profile of UV filters showed that the deposition of these compounds from encapsulated/entrapped stick formulation (F4) was significantly lower than that from UV filters stick formulations (F3) in the total slices of the skin and dermis. The comparative study between porcine skin and human skin demonstrated that the amounts of BZF-3 and AVO permeated and deposited in porcine skin were higher than in human skin for both formulations (F4 and FR - reference formulation). By the biodistribution technique it was possible to determine that the UV filters from the formulations F3 and FR presented higher retention of these compounds in the dermis than in other layers of the skin. On the other hand, it was observed that the encapsulated UV filters presented low retention rate into dermis


Subject(s)
Sunscreening Agents/analysis , Ultraviolet Rays/adverse effects , Silicates , Microscopy, Electron, Scanning Transmission/instrumentation , Silicon Dioxide/administration & dosage , Isotherm
19.
São Paulo; s.n; s.n; 2018. 181 p. ilus, graf.
Thesis in English | LILACS | ID: biblio-967948

ABSTRACT

Lipofuscin is an autofluorescent pigment progressively accumulated during cellular aging, in several tissues, such as heart, muscle and retina, especially in the postmitotic period. That phenomenon may result from oxidative stress, when biomolecules and organelles (mainly mitochondria) are damaged, generating non-degradable products inside lysosomes. Lipofuscin can be photosensitized, promoting photoxidative processes in cellular components. Many studies on lipofuscin were made using the human retinal pigment epithelial cells, but very little is known about lipofuscin from human skin. In this work we investigated the photoinduced formation (UVA and visible light) of lipofuscin and the consequence of its photosensitization by visible light. We also established an efficient protocol for the induction of lipofuscinogenesis, through specific damage in mitochondria and lysosomes. Cells that accumulated lipofuscin, after exposure to UVA and blue light, became sensitive to visible light (400-750 nm). We characterized the absorption and fluorescence emission of lipofuscin, as well as its fluorescence lifetime through the time resolved fluorescence microscopy (FLIM). We observed that lipofuscin in keratinocytes has absorption maximum in the blue region of light spectrum (420-450 nm), and maximum emission in the red. When photosensitized at 466 nm, lipofuscinloaded HaCaT cells had reduced cell viability, which was related with singlet oxygen generation, accumulated 8-oxo-dG premutagenic lesions and breaks in the DNA strand. Besides, we investigated the efficiency of different wavelengthsin visible light spectrum (408, 466, 522 and 650 nm) to promote lipofuscin formation due to damages in both mitochondria and lysosomes. Blue (408 and 466 nm) and green light (522 nm), but not red light (650 nm), promoted damage in mitochondria (membrane and DNA integrity) and lysosomes (membrane integrity and autophagic activity), effectively inducing lipofuscinogenesis. Thus, in addition to UVA, visible spectrum itself increases the sensitivity of keratinocytes to the visible light, through the generation of lipofuscin. Finally, we tested the carcinogenic potential of high-energy blue light (408 nm), by chronically irradiating HaCaT cells. For the first time in the literature, the formation of pyrimidine cyclobutane (CPD) dimers in the nuclear DNA of HaCaT cells was observed immediately or after several cycles of irradiation at 408 nm. We identified four major changes involved with the process of malignant transformation: genomic instability, decrease in the expression of tumor suppressor protein p16INK4a, increase in the proliferation rate and resistance to UVA-induced apoptosis


A lipofuscina é um pigmento autofluorescente acumulado progressivamente durante o envelhecimento celular em diversos tecidos, como o músculo cardíaco e retina, principalmente no período pós-mitótico. Esse fenômeno pode ocorrer em decorrência do estresse oxidativo, quando biomoléculas e organelas (principalmente mitocôndrias) sofrem danos, gerando produtos não degradáveis no interior dos lisossomos. A lipofuscina pode ser fotossensibilizada promovendo processos fotoxidativos nos componentes celulares. Muitos estudos de lipofuscina foram feitos em células do epitélio pigmentar da retina de olho humano, mas conhece-se muito pouco sobre a lipofuscina de pele humana. Neste trabalho nós investigamos a formação fotoinduzida (UVA e luz visível) de lipofuscina e as consequências da sua fotossensibilização pela luz visível. Nós também estabelecemos protocolos eficazes na indução de lipofuscinogênese, por meio de dano específico em mitocôndrias e lisossomos. Células que acumularam lipofuscina, após exposição à UVA ou luz azul, tornaram-se sensíveis à luz visível (400-750 nm). Caracterizamos as propriedades de absorção e de emissão da lipofuscina e seu tempo de vida de fluorescência, utilizando a microscopia de fluorescência resolvida no tempo (FLIM). Observamos que lipofuscina em queratinócitos tem máximo de absorção na região do azul (420-450 nm), com emissão máxima de fluorescência no vermelho. As células HaCaT carregadas com lipofuscina efotossensibilizadas no visível, tiveram redução da viabilidade celular, que foi relacionada com a geração de oxigênio singlete, bem como acumularam lesões pré-mutagênicas 8-oxo-dG e quebras na fita de DNA. Também, investigamos a eficiência de diferentes comprimentos de onda da luz visível (408, 466, 522 e 650 nm) em promover a formação de lipofuscina em consequência de lesões em mitocôndrias e lisossomos. Tanto a luz azul (408 e 466 nm) quanto a luz verde (522 nm), mas não vermelha (650 nm) promoveram dano em mitocôndrias (integridade de membrana e DNA) e lisossomos (integridade de membrana e atividade autofágica), induzindo eficientemente lipofuscinogênese. Logo, além de UVA, o próprio espectro do visível aumenta a sensibilidade de queratinócitos à luz visível, através da geração de lipofuscina. Por fim, testamos o potencial carcinogênico da luz azul de alta energia (408 nm), irradiando células HaCaT cronicamente. Identificamos quatro mudanças principais envolvidas com o processo de transformação maligna: instabilidade genômica, redução da expressão de proteína supressora de tumor p16INK4a, aumento da taxa de proliferação, e resistência à apoptose. Além disso, a formação de dímeros de pirimidina ciclobutano (CPD) no DNA nuclear de células HaCaT logo após ou depois de vários ciclos de irradiação com 408 nm foi observada pela primeira vez na literatura


Subject(s)
Skin , Keratinocytes/classification , Lipofuscin/adverse effects , Ultraviolet Rays/adverse effects , Light/adverse effects , Lipofuscin , Lysosomes
20.
São Paulo; s.n; s.n; 2018. 89 p. tab, ilus, graf.
Thesis in Portuguese | LILACS | ID: biblio-997822

ABSTRACT

Os efeitos deletérios causados pela radiação ultravioleta (UV) e o aumento significativo no diagnóstico de câncer de pele, confirmam a necessidade de um progresso significativo na pesquisa de produtos fotoprotetores eficazes e seguros, para proteção eficaz da pele. As formulações atuais associam filtros UV, orgânicos e inorgânicos, com eficácia limitada e que podem acarretar reações cutâneas adversas. O extrato de Vaccinium myrtillus L. (EVM) apresenta em sua composição compostos fenólicos, como as antocianinas, que possuem atividade antioxidante. O objetivo deste estudo foi avaliar formulações fotoprotetoras contendo extrato de Vaccinium myrtillus L. com amplo espectro de ação e concentrações reduzidas de filtros UV. As emulsões contendo ou não EVM e filtros orgânicos (octocrileno e metileno bis-benzotriazolil tetrametilbutilfenol) e inorgânico (dióxido de titânio) foram avaliadas e consideradas estáveis perante parâmetros pré-definidos. O perfil de segurança foi determinado pelo método in vitro Hen´s Egg Test - Chorioallantoic Membrane (HET-CAM) e o potencial antirradicalar do EVM foi confirmado pelo teste de DPPH• A formulação fotoprotetora acrescida de 5,0% de EVM foi avaliada quanto à eficácia fotoprotetora in vivo e in vitro e não demonstrou aumento significativo no FPS quando comparada à formulação que continha somente os filtros solares e, no ensaio referente à hidratação da pele, não houve alteração nos dados, segundo teste de eficácia clínica. Os resultados obtidos sugeriram que mesmo não apresentando aumento no valor de FPS in vivo, a formulação fotoprotetora contendo o extrato, poderia atuar como agente antioxidante evitando os danos provocados pela radiação UV


The deleterious effects caused by ultraviolet radiation (UV) and the significant increase in the diagnosis of skin cancer confirm the need for significant progress in researching effective and safe sunscreen products for effective skin protection. Current formulations associate UV, organic and inorganic filters with limited efficacy that can lead to adverse skin reactions. Vaccinium myrtillus extract (EVM) contains in its composition polyphenols compounds, such as anthocyanins, which have been antioxidant activity. The objective of this study was to evaluate sunscreens containing EVM with broad action spectrum and reduced concentrations of UV filters. Emulsions containing or not EVM and organic (octocrylene and methylene bis-benzotriazolyl tetramethylbutylphenol) and inorganic (titanium dioxide) filters were evaluated and considered stable under pre-defined parameters. The safety of the emulsion was assessed was determined by the in vitro Hen´s Egg Test - Chorioallantoic Membrane method (HET-CAM) and the antiradical potential of EVM was confirmed by the DPPH• test. The sunscreen formulation containing EVM 5.0% was photoprotective efficacy evaluated in vivo and in vitro and did not show a significant increase in SPF when compared the formulation only with UV filters and no improves skin hydration, according to clinical efficacy assay. The results of the study suggest that even without increase SPF in vivo, the sunscreen formulation containing the extract may show antioxidant activity avoiding damage caused by UV


Subject(s)
Sunscreening Agents/pharmacology , Plant Extracts/analysis , Vaccinium myrtillus/adverse effects , Ultraviolet Rays/adverse effects , In Vitro Techniques , Emulsions , Sun Protection Factor , Antioxidants
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