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The present study applied peer leader modeling and the use of posted feedback and goals to increase the occurrence of protective behaviors for skin cancer at two swimming pools. During the intervention phase, the models, pool lifeguards, wore sunglasses and special t-shirts and hats, used zinc-oxide and sun screen, and sat in the shade. The posted feedback was the "Percentage of pool patrons from the previous day who engaged in two or more protective behaviors. The protective behaviors measured were wearing shirts, hats or sunglasses, using zinc-oxide, and being in a shaded area. The feedback also consisted of a goal percentage to reach for that day. The results indicated that for Pool 1, substantial increases from the baseline to the intervention phase in behaviors were observed. The most dramatic increases were observed for the remaining in a shaded area measure. from 20% to 55% during intervention. Adolescents increased Adults increased from 15% to 39% during intervention. No changes occurred at Pool 2 until the intervention was introduced. / Master of Science

For older couples facing a skin cancer diagnosis, the experience is stressful, not only for the individual with the diagnosis, but also for the healthy partner. Couples may use various types of coping and styles of support to deal with the stress, including relationship-focused support, which addresses the needs and coping efforts of both partners in response to and in conjunction with one another. The current study examined associations between perceptions of three styles of relationship-focused partner support, namely active engagement, protective buffering, and overprotection, and body image of the partner with skin cancer and quality of life of the partner with skin cancer and the healthy partner. Using data collected from 30 older couples (Mage = 70; SD = 7.25) with diagnoses of melanoma (n = 14; 47%) or nonmelanoma (n = 16, 53%), linear regression models, adjusted for the stressor appraisal by both partners, revealed that when partners with skin cancer reported receiving higher active engagement support, they were more likely to have a positive body image (B [unstandardized] = 35.54, p = .04). A significant interaction was found between active engagement support used by both partners (B = -8.78, p = .05), indicating that active engagement from healthy partners appears to benefit the body image of the partner with skin cancer when they themselves use less active engagement support. Both protective buffering and overprotection support were not associated with body image. Multivariate actor-partner interdependence models (APIM) assessed the relationships between support received by each partner and its association with their quality of life (actor effects) and their partner's quality of life (partner effects). Results suggest that active engagement support perceived by either partner was not associated with quality of life. In contrast, overprotection perceived by partners with skin cancer was significantly associated with their quality of life (actor effect: B = -10.81, p < .001), but was not associated with the healthy partners' quality of life. Additionally, protective buffering perceived by healthy partners was associated with their own quality of life (actor effect; B = -6.91, p = .05) as well as their partner with skin cancer's quality of life (partner effect; B = -8.15, p = .01). Nuances based on the sex of the person with skin cancer, type of skin cancer, the stage of skin cancer and couple's appraisal of the stressors of skin cancer are also discussed. Findings suggest that actively engaging with the stressors of skin cancer can contribute to positive views of one's body, whereas ignoring or avoiding conversations about skin cancer and overprotection provided by healthy partners might lead to poorer quality of life for both partners. These findings illustrate the influence of healthy partners, highlighting that how they give support when their partner is facing a skin cancer diagnosis may affect the overall quality of the couple relationship and couple outcomes. / Ph. D.

A terapia fotodinâmica (TFD) associada à administração tópica de agentes fotossensibilizantes é uma terapia promissora para o tratamento tópico do câncer de pele. A protoporfirina IX (PpIX) é uma substância fotodinamicamente ativa usada na TFD, entretanto, devido a sua alta lipofilia ela forma agregados em meio aquoso, o que diminui sua atividade fotodinâmica e dificulta sua administração na pele. Assim, sistemas de liberação nanoparticulados vêm sendo investigados para melhorar a distribuição da PpIX na pele e facilitar sua penetração até as células tumorais. Os dendrímeros de poliamidoamina (PAMAM) representam uma nova geração de nanosistemas que tem despertado grande interesse nos últimos anos. Eles são uma classe especial de polímeros que apresentam estrutura muito ramificada e regular e que interagem com a PpIX formando complexos (nanopartículas dendriméricas de PpIX-PAMAM). A aplicação de uma corrente elétrica de baixa intensidade, conhecida como iontoforese, pode influenciar na penetração cutânea dessas nanopartículas, direcionando-as para o interior das células. Desta forma, o objetivo deste trabalho foi avaliar a influência da iontoforese e de nanopartículas de PAMAM de geração 4 hidroxilado (PAMAM G4-OH) com a PpIX na localização subcelular e penetração deste agente fotossensibilizante em tumores cutâneos. Assim foram preparados complexos de PpIX-PAMAM, os quais foram caracterizados em função do tamanho de partículas e potencial zeta. A localização subcelular da PpIX a partir dos complexos foi investigada em carcinoma de células escamosas. A influência dos complexos na geração de oxigênio singleto quando a PpIX sofre irradiação também foi avaliada. Por fim, a penetração da PpIX a partir dos complexos PpIX-PAMAM foi avaliada, in vivo, em pele sadia e em tumores induzidos em camundongos Nude BalbC, com e sem aplicação da iontoforese. O tamanho médio das nanopartículas dendriméricas contendo a PpIX dispersas em meio aquoso foi de aproximadamente 220 nm. Quando avaliadas em função do tempo, este tamanho sofreu um aumento de apenas 5% depois de 24 h, permanecendo constante por 7 dias. O potencial zeta das dispersões foi de 10 mV, em pH 7, e de 30 mV, em pH 5,5, possibilitando a contribuição da eletromigração durante a iontoforese. Nos estudos em cultura de células tumorais observou-se que a complexação com o PAMAM aumentou 30 vezes a localização da PpIX na mitocôndria quando comparada a PpIX livre. Além disso, a quantidade de oxigênio singleto gerada foi semelhante para a PpIX livre não agregada e complexada, 4,3 x 10-3 e 4,6 x 10-3 , respectivamente, sugerindo que o PAMAM manteve a atividade fotodinâmica da PpIX. Nos experimentos in vivo, em pele sadia, verificou-se que a PpIX administrada a partir do complexo com o PAMAM se distribuiu homogeneamente pela pele, enquanto que a PpIX livre apresentou uma fluorescência localizada em apenas algumas área da superfície da pele. A iontoforese facilitou a penetração da PpIX para as camadas mais profundas da pele. Finalmente, no tratamento dos tumores cutâneos, a administração tópica dos complexos por apenas 30 min possibilitou a penetração da PpIX até os tumores localizados abaixo da pele, em concentrações semelhantes para a aplicação passiva e iontoforética. Portanto, a complexação da PpIX com o PAMAM é um sistema de liberação nanoparticulado promissor para o tratamento tópico de tumores cutâneos por TFD. / Photodynamic therapy (PDT) associated with topical administration of photosensitizer agents is a promising therapy for topical treatment of skin cancer. Protoporphyrin IX (PpIX) is a photosensitizer commonly used in PDT; however, due to its high lipophilicity it aggregates in aqueous medium, which decreases its photodynamic activity and hinders its penetration through the skin. In this way, nanoparticles have been designed to improve the distribution of PpIX in the skin and enhance its tumor cell penetration. The polyamidoamine dendrimers (PAMAM) represent a new generation of nanosystems that has aroused great interest in recent years. They are hyberbranched polymers capable to form complexes with PpIX (PpIX-PAMAM), increasing PpIX aqueous solubility. The application of a low intensity electrical current, known as iontophoresis, may influence the nanoparticles skin penetration, directing them to the tumor cells. Therefore, the aim of this study was to evaluate the influence of iontophoresis and PpIX-PAMAM G4-OH complexes in PpIX subcellular localization and penetration into skin tumors. The complexes were prepared and characterized as a function of particle size and zeta potential. The subcellular localization of PpIX from the complexes was investigated in squamous cell carcinoma. The influence of PpIX-PAMAM on the generation of singlet oxygen after irradiation was also evaluated. Finally, the penetration of PpIX from the PpIX-PAMAM complexes was evaluated in vivo in healthy skin and in tumors induced in BalbC nude mice with and without application of iontophoresis. The average size of PpIX-PAMAM nanoparticles dispersed in aqueous medium was approximately 220 nm. When evaluated as a function of time, this size was increased only 5% after 24 h and remained constant for 7 days. The zeta potential of the dispersions was 10 mV at pH 7 and 30 mV at pH 5.5, allowing the contribution of electromigration during iontophoresis. In studies in culture tumor cells it was observed that complexation with PAMAM increased 30 times the localization of PpIX in the mitochondria compared to free PpIX. Furthermore, the amount of singlet oxygen generated when PpIX-PAMAM was irradiated was similar to that generated by the irradiation of the non-aggregated free PpIX, 4.6 x 10-3 and 4.3 x 10-3, respectively, suggesting that PAMAM did not modify the photodynamic activity of PpIX. In vivo experiments on healthy skin have shown that PpIX from the PpIX-PAMAM was homogeneously distributed throughout the skin, whereas free PpIX fluorescence was visualized only in some restricted areas of the skin surface. Iontophoresis facilitated PpIX diffusion to deep layers of the skin. Finally, the treatment of skin tumors have shown that the topical administration of the PpIX-PAMAM for only 30 min, passively or by iontophoresis, allowed the penetration of PpIX into the tumors located below the skin. Therefore, the PpIX complexation with PAMAM is a promising nanoparticle delivery system for the topical treatment of skin tumors by PDT.