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Juliana Brandstetter Vilar 0 JULIANA BRANDSTETTER VILAR MECANISMOS DE REPARO DE DNA ENVOLVIDOS COM LESÕES INDUZIDAS POR AGENTE ALQUILANTE (NIMUSTINA) EM CÉLULAS HUMANAS E SUA ASSOCIAÇÃO COM A RESISTÊNCIA DE GLIOMAS Tese apresentada ao Programa de Pós- Graduação em Microbiologia do Instituto de Ciências Biomédicas da Universidade de São Paulo, para obtenção do Tìtulo de Doutor em Ciências. São Paulo 2014 1 JULIANA BRANDSTETTER VILAR MECANISMOS DE REPARO DE DNA ENVOLVIDOS COM LESÕES INDUZIDAS POR AGENTE ALQUILANTE (NIMUSTINA) EM CÉLULAS HUMANAS E SUA ASSOCIAÇÃO COM A RESISTÊNCIA DE GLIOMAS Tese apresentada ao Programa de Pós-Graduação em Microbiologia do Instituto de Ciências Biomédicas da Universidade de São Paulo, para obtenção do Tìtulo de Doutor em Ciências. Área de concentração: Microbiologia Orientador: Dr. Carlos Frederico Martins Menck Versão original São Paulo 2014 2 Colic ença. Eu peço licença para ocupar esta página com uma homenagem, ainda que tardia. Eu preciso der 3 um pouco de justiça à luz daqueles que por aqui pousarem seus olhos, ou além... Poderia alguém querer negligentemente passar adiante... Mas desaconselho. Para 4 5 6 Esta tese é o resultado de muitos experimentos e de incontáveis experiências. Ao final de cada linha, poder-se-ia desenrolar um novelo. Desenrolo-o. Desfio-o pelo avesso, como quem mostra o reflexo do espelho. Antes de ser uma tese, esta era um projeto e, antes de sê-lo, era um sonho. Sonhado de forma modesta e imprecisa por sua autora, pela autora da autora, e pela autora desta: No centro do mundo, interior de Goiás, uma mulher chamada Maria, costureira, analfabeta, talvez por não reconhecer qualquer letra dava valor à palavra; e esta lição ensinou aos seus filhos e netos. Maria, minha saudosa avó, gerou à Diná, minha amada mãe, que gerou a mim. Sou a filha única desta coleção de histórias, embora haja outras. Meu passado está repleto da presença de minha mãe. O meu caráter, lapidado por seus bons exemplos; Minhas conquistas, alicerçadas por sua força. Eu não saberia definir o instante exato em que passamos a compartilhar o mesmo sonho. Nem tampouco apontar quando não houve de sua parte o mesmo esforço. Testemunha da minha vida, eu bem sei que nada poderia privá-la deste momento de celebração... Meu coração se derrama como a champagne que não se aguenta contida em si mesma! Ele a procura para o nosso brinde, esta é a hora da cumplicidade do nosso abraço, de nos olharmos aliviadas e vermos através dos olhos que, enfim, alcançamos o que buscávamos... Ela, porém, não está mais aqui. Insensata morte... Que separa os filhos dos pais na hora da paga por seu trabalho. E se já não mais nos veremos... E estaremos infinitamente distantes neste ponto da existência - onde poderia eu, gaivota em vôo raso, depositar as rosas multicores de gratidão que desabrocharam em meu peito? Uma parte está escrita aqui: Sua memória será reconhecida pelas boas coisas que me fez, embora não as tenha feito apenas a mim... E saberão todos que tudo o que alcancei foi porque a tive comigo desde o princípio da minha jornada. Este é o princípio da justiça. E a parte que sobrar, o amor que ultrapassa o limite das palavras, peço ao Senhor, Deus meu, que colha todas essas flores; que recolha todas as minhas lágrimas; e as torne um agradável perfume para o seu descanso. 7 AGRADECIMENTOS Ufa! Parecia que não ia acabar nunca. Mas acaba. Os ciclos se fecham e no mesmo instante que se coloca o ponto final sente-se na sua pausa a saudade. E a nostalgia. Como é difícil olhar para trás, para esses anos de trabalho, sem marear os olhos! Me lembro quando entrei no mundo da ciência e acompanhava nas palestras, anônima, ao Prof. Dr. Menck. Eu o observei por anos: da minha iniciação científica aos meus anos como professora substituta na UFG (substituta, gente!). E sempre fomentei a esperança de vir para São Paulo tê-lo como meu orientador. Eu vim quase como uma retirante, com mais coragem do que planos, na bagagem. Quanta ousadia sair de um instituto onde tudo e todos me eram conhecidos, onde eu houvera formado praticamente uma segunda família e migrar para o incerto na Paulicéia Desvairada. E então fui aceita em seu laboratório. Que desafio e responsabilidade! E por isso, e por muito mais, tenho tanto a agradecer ao meu querido Prof.! Por ter aceitado me orientar no meu doutorado; pela paciência em ensinar, pelo respeito ao meu próprio tempo e condição humana, por ter me incentivado e, assim, proporcionado a melhor experiência da minha vida e do meu filho, que foi nossa ida para Alemanha; por sua maneira de acreditar em seus alunos, nos fazendo crescer, e por sua capacidade de nos surpreender positivamente sempre! Um professor e pesquisador exemplar! Que bom poder participar da história de um cientista tão brilhante e de um ser humano tão afável. É um privilégio! Obrigada, Prof.! Ainda, outros professores também forjaram em mim o pensamento científico, me inspiraram a seguir a carreira científica e me incentivaram a alçar vôos para além de onde eu lia nas paredes “Ama esta casa como se fora outra casa de teus pais”: minha orientadora de IC e do mestrado, Dra. Lee Chen Chen. Dr. Alexandre (o Coelho), Dra Ludmila, Dr. Lázaro (o Batata), Dr. Athur (o Rei), Dr. João Batista e (meu tio) Dr. Edward (Madureira), que até reitor virou! Todos professores excepcionais da UFG. Quantas saudades sinto das tiradas estatísticas, que me induziram estudar biometria sem sentir dor (ou quase!). Havia um preço alto a se pagar para poder entender e rir da piada! Saudades das nossas rodas de viola, nossas festas de fim de ano e amigos- secretos sem marmelada, nossas cantorias nos ônibus para as conferências e, enfim, da viola na praça, que de noite tomava o lugar da tenda da genética, nos congressos da vida. Foi um privilégio tê-los como professores e amigos! I might also thank very much Dr. Bernd Kaina, who received me in Germany as a guest cientist at the Institute of Toxicology of the University of Medicine of Mainz and gave me support to finish my Phd thesis. This was such unbelievable great enriching cientific and personal experience in my life. Thank you very much for your kindness in receiving me and my son, for your supervision and support! I would like to thank also Dr. Theodora Nikolova, for her 8 hospitality in relation to us, colaboration in the lab work and the opportunity to contribute as a co-author for the review paper in nitrosoureas we have written. I am also greatful for the kind technician Anna, who helped me with the commet assays. I should also give a very special thank to Dr. Marcus Eich, who took really care of me while I was in Germany and since: my collegue who became a friend, then my oficial german- english transltator, my rides to work through the seasons as I have never experienced before: such flowering spring, vivid summer, coloured autumn and the white winter. Then my best friend, my colaborator, support, advisor, my effective help in difficult times, my therapist from Sunday to Friday. My allarm. You did so much for me! You have such a big heart! Nothing I can say would be enough to express my gratitude and joy for our friendship! Thank you for not let me give up. And specially, thank you for not giving up of me! I was so lucky to meet you! Ainda: ao atual Prof. da Universidade de Washington, Dr. Luiz F. Z. Batista, que me supervisionou no lab assim que comecei, me ensinou os meus primeiros passos em cultura de células, me ajudou a pensar o meu projeto de doutorado e teve comigo as conversas que eu precisava e que me prepararam para encarar o lado negro da força. Lu, seu brilhantismo, humildade e simpatia foram grandes exemplos para mim. A prova de que pessoas realmente inteligentes e competentes não precisam pisar em ninguém para seguir e ser reconhecido. Obrigada! À minha querida amiga e colega Clarissa, que colaborou comigo em diversos experimentos que talvez eu levasse uma vida até adquirir a experiência necessária para fazê-los bem feitos sozinha. Claris, você é outro grande exemplo para mim. Sua competência é surpreendente e sua alma iluminada! Obrigada pelas tardes de trabalho tão produtivas quanto divertidas. Obrigada pelas conversas, pelo incentivo e por seu caráter, que mesmo em meio aos vendavais, nunca mudou com o vento. Então, preciso agradecer de forma muito especial também às minhas colegas e amigas do lab: Lígia, Alessandra e Letícia. Não é eufemismo dizer que vocês possivelmente salvaram a minha vida, quando no pico da minha doença me levaram para suas casas e cuidaram de mim. Que entenderam minhas limitações e sem julgamentos só me ajudaram. Foram minhas terapeutas, minhas fiéis escudeiras, incentivadoras do meu trabalho. E à Lí, que no fim desta tese, ficou ao meu lado, revisando-a comigo, para que o fim chegasse mais rápido. Do fundo do meu coração: obrigada, babies! Agradeço profundamente à Eliza, que era secretária do nosso lab. Mas que tornou-se minha grande amiga, que me adotou e se tornou minha mãe paulistana. Eliza, obrigada por seu 9 trabalho, que tornava a nossa vida tão mais fácil. Obrigada pelas orações, pelos abraços, pelas conversas, por todo apoio, por estar sempre ao meu lado. Você faz muita falta no lab e na minha rotina! E à Maria Helena, cujo trabalho e alegria tornam nosso trabalho menor e mais feliz! Obrigada, também, à todos os colegas do lab, pois apenas com uma equipe assim tão competente criamos um ambiente tão rico e colaborativo, que possibilitou as trocas necessárias para o nosso desenvolvimento coletivo.
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