Made available in DSpace on 2014-07-29T16:19:12Z (GMT). No. of bitstreams: 1 dissertacao paulo junior letras.pdf: 1017842 bytes, checksum: 2ee704ffb6efbfcfd92fddd3114ea073 (MD5) Previous issue date: 2009-04-01 / This work is a research about the writer Yêda Schmaltz, this poetry that revives the Eros face through the mytological characters Penélepe, Dioniso, Áthis, Eco, Narciso and other myths. The initial propose is to study the complete works of the poetry especially books like A alquimia dos nós, Baco e as Anas brasileiras, A ti Áthis and Ecos: a jóia de Pandora, works that show better the Eros images, besides that she uses the Greek mytology. First of all we used works about mitology and platonic philosophy to understand how the God of love is showed on the Ocident. We used too a lot of poets that maked of love feeling as subject for his poems, like Safo, Petrarca, Camões and Álvares de Azevedo. Our objetive is seeing how Yêda Schmaltz is an heir of this poets. So we arrived at the conclusion that Yêda Schmaltz makes a modern poem when she revives Eros. According to Alfredo Bosi the subjective about the poems is giving the ways of the resistence of modern artists / O presente trabalho é uma leitura da obra em verso da escritora goiana Yêda Schmaltz, poeta que revive a imagem de Eros através das figuras mitológicas de Penélepe, Dioniso, Áthis, Eco e Narciso, dentre outras. A proposta inicial deste estudo é trabalhar a obra completa da escritora, em especial A alquimia dos nós, Baco e as Anas brasileiras, A ti Áthis e Ecos: a jóia de Pandora, obras que apresentam amostragens mais definidas das máscaras de Eros, além de estarem visivelmente assentadas sobre o lastro mitológico. Nesse sentido, inicialmente nos valemos dos trabalhos de mitólogos e filósofos do platonismo para entender as configurações tomadas pelo deus do amor no Ocidente, bem como de parte das vertentes poéticas que a história da literatura não legou ao esquecimento, e que se tornaram exemplares para a lírica que toma o sentimento amoroso como motivo poético. Poesias de Safo, Petrarca, Camões e Álvares de Azevedo são visitadas a fim de perceber em que medida Yêda Schmaltz torna-se herdeira de uma tradição lírica-amorosa. Verifica-se que a obra poética de Yêda Schmaltz assume uma forma modelar de reinventar o mito de Eros na modernidade e, numa perspectiva bosiana, percebe-se que poetas intimistas tomam esse viés como uma das formas de resistência característica de artistas modernos

O presente trabalho tem por objetivo problematizar a inserção da teoria das pulsões no pensamento de Herbert Marcuse, mais especificamente em sua obra publicada em 1955 sob o título Eros e civilização: uma interpretação filosófica do pensamento de Freud. Aproximadamente três décadas antes a essa publicação de Marcuse, Freud publicou a obra que rearticulou como um todo o seu pensamento: o ensaio sobre a hipótese da Pulsão de Morte. Tal foi a sua repercussão, tanto clínica como cultural, que fez com que a psicanálise avançasse em temas como o masoquismo, a compulsão à repetição, a psicologia de massas e a destrutividade, chegando mesmo a problematizar o desenvolvimento cultural humano em sua possibilidade de garantir a vida comunal diante de uma pulsão para além do princípio de prazer. Não obstante, a recepção dessa conceituação provocou diversas revisões da psicanálise. Dentre as que aqui interessam, destacaram-se aquelas que foram atravessadas pelas questões relativas ao socialismo, já que questionaram a condição de imutabilidade da Pulsão de Morte. Contudo, as propostas desse Revisionismo Neofreudiano, que tentava articular marxismo e psicanálise, culminaram na extirpação da teoria das pulsões, dessexualizando a psicanálise. Ao criticar essa tendência popular, à época, a obra de Marcuse renovou o impasse: como inserir a metapsicologia, especialmente o conceito de Pulsão de Morte, no contexto das pesquisas do Instituto para Pesquisa Social de Frankfurt, fundamentalmente marxista? O autor realocou a psicanálise no debate crítico sobre a cultura, renovando também outra questão que se vinculava à Pulsão de Morte: a relação entre dominação e progresso constituiria realmente o princípio da civilização? Sob esse contexto, a presente pesquisa articulou os seguintes pontos, a fim de esclarecer as ressonâncias da teoria das pulsões no pensamento de Marcuse: a) buscou-se esclarecer a crítica marcuseana às escolas culturalistas Neofreudianas; b) procurou-se compreender alguns pontos da conceituação sobre a Pulsão de Morte na obra de Freud; c) e, por fim, os desdobramentos dessa pulsão na obra Eros e civilização. Pode-se apontar que Marcuse centrou o debate sobre a cultura no conflito entre os princípios de prazer e realidade. Entretanto, o autor não negou a Pulsão de Morte em suas análises, mas a sua atividade numa realidade regida pelo princípio de desempenho, comparada com sua atividade regida por um mais além princípio de desempenho, já que, aliviada a tensão, pouco se expressaria. Problematizou-se a conclusão dessa obra, pois, não sendo a Pulsão de Morte somente alívio de tensão, ela insistiu na dinâmica da civilização como negação do indivíduo. A proposição de uma utopia foi questionada posteriormente pelo próprio autor e, assim, permaneceu seu posicionamento crítico, na medida em que compreendeu, nas próprias conceituações da psicanálise, a negação do existente, ou seja, a revelação da negação do indivíduo / The present work aims to debate the insertion of the drive theory in Herbert Marcuses thinking, as per, more specifically, this authors work Eros and Civilization: a philosophical inquiry into Freud published in 1955. Approximately three decades before this Marcuses publication, Freud had published a work which articulated his thinking as a whole: the essay on the hypothesis of the death drive. The great repercussion of the former work, in both clinical and cultural terms, made psychoanalysis advance in themes such as masochism, compulsion to repetition, crowd psychology and destructivity, besides having discussed human cultural development within its possibility of guaranteeing communal life in the face of a drive, which goes beyond pleasure principle. Nevertheless, the approach of this new concept provoked many reviews in the psychoanalysis area one of which we can highlight. Questions related to socialism were examined, as they referred to the immutability of the condition of the death drive. However, the proposals of this Neo-Freudian Revisionism which tried to merge Marxism and psychoanalysis, terminated in the extirpation of the theory of drives and generated an opposed movement to the previously accepted eroticization of psychoanalysis. As Marcuses work criticized such a popular trend at that time, it renewed the dilemma: how to insert metapsychology, particularly the death drive concept, in the context of the researches carried out in the Institute of Social Research of Frankfurt which was fundamentally Marxist? The author reallocated psychoanalysis in the midst of critical debate on culture, and also renewed another inquiry that is linked to the death drive: would the relationship between dominance and progress really constitute the principle of civilization? In this context, this research discussed the following points to clarify the echoes of the drive theory in Marcuses thinking: a) by trying to elucidate Marcusean critical theory to the Neo- Freudian culturalist schools; b) by analyzing some elements in the concept of death drive in Freuds work; c) ultimately, by understanding the outcome of death drive in Eros and Civilization: a philosophical inquiry into Freud. Furthermore, we can point out that Marcuse focused the debate about culture on the conflict between the principles of pleasure and reality. Still, the author did not discredit death drive itself in his analysis, but its mechanisms in a reality led by performance principle if compared to the previously referred drives action conducted by a beyond the performance principle, as the death drive would be nonexpressive after tension had been released. Also, the conclusion of that book was examined, as death drive is not only tension release. Moreover, that work insisted on the point that the dynamics of civilization can be considered a denial of the individual. The proposition of a utopia was questioned afterwards by the author himself. Thus, his assertion remained a critical one as Marcuse understood the denial of the existent in his own concept of psychoanalysis, that is, the revelation of the negation of the individual

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-08-27T19:10:55Z No. of bitstreams: 1 andreyurigomesabijaudi.pdf: 897693 bytes, checksum: f85ec06c9f1efb15a21b38b8db4a2c74 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-08-28T12:10:09Z (GMT) No. of bitstreams: 1 andreyurigomesabijaudi.pdf: 897693 bytes, checksum: f85ec06c9f1efb15a21b38b8db4a2c74 (MD5) / Made available in DSpace on 2018-08-28T12:10:09Z (GMT). No. of bitstreams: 1 andreyurigomesabijaudi.pdf: 897693 bytes, checksum: f85ec06c9f1efb15a21b38b8db4a2c74 (MD5) Previous issue date: 2018-05-25 / O objetivo desta dissertação é analisar como Paul Tillich compreende e relaciona os conceitos de amor e ontologia em suas diversas obras. É possível perceber no decorrer do texto que Tillich apresenta o amor enquanto princípio ético e fundamento ontológico e, por isso, traz consigo muitas ambiguidades. Desta forma, ele explora o conceito de amor a partir daquilo que chama “diferentes qualidades”, tomando como referência as compreensões gregas de eros, philia, epithymia (ou libido) e agápe. A hipótese que norteia este trabalho é que há uma linha de raciocínio presente no pensamento de Tillich, que parece a todo momento insistir na superação das ambiguidades da vida e do caráter fragmentário ao qual está sujeito o ser humano. Por isso, discute-se questões essenciais como seu entendimento sobre ontologia, sua compreensão sobre a importância do mito na linguagem religiosa e sua interpretação da queda como a transição da essência para a existência que resulta na alienação existencial. Mas o foco da dissertação é explorar como Tillich apresenta o poder do amor como aquele que reúne o ser humano com Deus, fundamento de seu ser; com seu próximo; e, principalmente, consigo mesmo. Por fim, o texto expõe como Tillich compreende que a relação entre agápe e eros é essencial para se compreender o amor como uma força una e indivisível, capaz de encerrar as ambiguidades da vida e se apresentar como graça ao ser humano, abrindo possibilidades de superação das leis e da problemática da contextualização da ética nas transições históricas do mundo. / The purpose of this dissertation is to analyze how Paul Tillich understands and relates the concepts of love and ontology in his various works. It is possible to perceive throughout the text that Tillich presents love as an ethical principle and ontological foundation and, therefore, brings with it many ambiguities. In this way, he explores the concept of love from what he calls "different qualities", taking as reference the greek understandings of eros, philia, epithymia (or libido) and agape. The hypothesis that guides this work is that there is a line of reasoning present in Tillich's thought, which seems at all times to insist on overcoming the ambiguities of life and the fragmentary character to which the human being is subjected. Hence, essential questions such as his understanding of ontology, his understanding of the importance of myth in religious language, and his interpretation of the fall as the transition from the essence to the existence that results in existential alienation are discussed. But the focus of the dissertation is to explore how Tillich presents the power of love as one that reunites human being to God, the foundation of his being; with his neighbor; and especially with himself. Finally, the text exposes how Tillich understands that the relationship between agape and eros is essential for understanding love as a single and indivisible force, capable of closing the ambiguities of life and presenting itself as grace to the human being, opening possibilities for overcoming the laws and the problematic of the contextualization of ethics in the historical transitions of the world.

La présente thèse est née d’une interrogation sur le véritable rôle de l’iconographie de l’Éros adolescent, c’est-à-dire de l’adolescent érotisé, dans la culture occidentale et plus précisément sur l’enjeu et les fonctions que représente son image en tant que symbole d’amour, de beauté et de désir dans le cadre de la pédérastie en Europe et plus précisément dans l’Allemagne Wilhelmienne dans le contexte de l’intensification de la répression sexuelle au tournant du XXe siècle. Pour les Grecs, c’est le corps juvénile masculin avec ses charmes particuliers qui représente le plus beau sexe et le bon objet de plaisir. C’est une erreur fondamentale de croire que cette beauté était valorisée à cause de son parentage avec le corps féminin. La beauté de ses traits était liée à un certain charme et à des caractéristiques particulière au corps et à l’esprit masculins en voie de se former : la vivacité de l’esprit, la vigueur, la résistance, la force, l’endurance, la ténacité, l’ardeur, la fougue et l’enthousiasme faisaient partie de cette beauté que les garçons se devaient de renforcer par la pratique régulière d’exercices intellectuels et physiques. L’éducation pédérastique des garçons, garante des valeurs masculines, assurait que leur grâce et leur raffinement ne sombreraient pas dans la mollesse et l’effémination. L’ambiguïté féminine, l’androgynie qui sera perçue plus tard comme une caractéristique de la beauté adolescente mâle, plus encore, comme la raison de cette beauté, était plutôt, à cette époque, ce dont les garçons devaient se préserver et être préservés. Ainsi, le statut du jeune mâle lui confère, depuis la Grèce antique, un rôle prédominant dans la culture occidentale et explique, en partie, l’omniprésence de ses représentations dans l’art et la littérature européennes jusqu’au XIXe siècle. Pourtant, l’iconographie et la propagande autour de son image se transforment progressivement et fatalement jusqu’à l’aube de la Première Guerre mondiale. C’est notamment l’association de son image à l’érotisme et la beauté qui devient progressivement un tabou honteux, voire pervers. Instrumentalisée et esthétisée selon les intérêts de différents groupes qui s’opposent, le contrôle de l’iconographie et de la sexualité de l’adolescent devient, de cette manière, un enjeu majeur du pouvoir à la fin du XIXe et au tournant du XXe siècle. Ce phénomène est européen mais le Reich wilhelminien, en construction et en quête d’identité, représente un exemple idéal pour analyser ce phénomène que nous replaçons, d’une part dans le contexte de la répression sexuelle et, d’autre part, dans le contexte des mouvements de jeunesse et de contestation qui se développent parallèlement au cours de cette période. Notre étude, basée sur des observations et des faits précis, a l’audace d’essayer de comprendre un phénomène tabou et représente une invitation à une réflexion sur le destin de la beauté masculine et des amours masculins dans notre société. Nous invitons le lecteur à remettre en question certaines de ses convictions et nous espérons réussir à redonner à l’Éros adolescent, trop souvent censuré et négligé, au moins partiellement, la place qu’il mérite dans l’histoire européenne en insistant sur le rôle qui fut le sien dans l’art et la littérature ainsi que sur les enjeux et les fonctions qu’il a si souvent représentés dans les conflits politiques et sociaux. / The following thesis arose from an analysis of the actual role which the iconography of the adolescent Eros, i.e. the eroticized juvenile, plays in the western culture. More precisely, it is about the issue and the functions of its image as a symbol of love, beauty and desire in the framework of pederasty in Europe and more precisely in Wilhelminian Germany in the context of intensified sexual oppression at the turn of the 20th century. For the ancient Greeks, it was the young male body with its particular charms which represented the most beautiful gender and which was a fine object of pleasure. It is totally wrong, however, to believe that the value of this beauty was increased because of its descent from the female body. The beauty of its features was connected with certain charms and characteristics which are particular of the male body and spirit that are on their way to develop : A liveliness of the spirit, strength, power of resistance, endurance, toughness, verve, impetuosity and enthusiasm were part of this beauty which the boys had to intensify through regular mental and physical exercises. The boys’ pederastic education, a guarantee of male values, made sure that their grace and sophistication would not disappear into softness and effeminateness. Female ambiguity, the androgyny which will be seen later as a characteristic of juvenile male beauty or – even more – as a reason for male beauty, was at this stage rather something that the boys had to avoid or had to be sheltered from. Thus, the status of the young male has given him – since ancient Greece – a predominant role in western culture, which partly explains the omnipresence of his representation in European art and literature until the 19th century. However, the iconography and the propaganda about his image are transformed gradually and fatally till the beginning of the First World War. It is especially the association with eroticism and beauty which becomes gradually a taboo, something disgraceful or even perverted. Either instrumentalized or aestheticized – according to the interests of the different opposing groups – the control of this iconography and sexuality of the juvenile becomes in this way a great matter of dispute of power at the end of the 19th century and at the turn of the 20th century. This phenomenon is a European one but the Wilhelminian Reich – under construction and on a quest for identity – represents an ideal example for analyzing this phenomenon which on the one hand I put into the context of sexual oppression and on the other hand into the context of youth movements and contestation developing in parallel ways over this period of time. In my research – based on both observations and precise facts – I dare to try to understand a taboo phenomenon and I invite the reader to reflect upon the destiny of male beauty and male love in our society. The readers are invited to question some of their convictions and I hope I succeeded in giving back to juvenile Eros – too often censured and neglected, at least partially – the place he deserves in European history, insisting both upon the role he had in art and literature as well as on the issues and functions which he represented so often in political and social conflicts.

Denna utforskande vetenskapliga essä vill fördjupa och begreppsliggöra ett praktiskt kunnande för en psykoterapeut utifrån en berättelse från en arbetsdag i dennes profession. Ett inledande citat av nobelpristagare Olga Tokarczuk: ”Känsligheten som den allra blygsammaste formen av kärlek (…)”, blir essäns avstamp som sedan följs och vars betydelse vävs samman med berättelsen. En överordnande undran vid essäns avfärd är vad begreppet känslighet, uppmärksamhet och kärlek har för betydelse för psykoterapeuten i sin profession. Olika filosofers, författares och poeters texter och berättelsen väver i essän fram det praktiska kunnandet, omdömet och kraften i att vara den som finns för en annan som lider och samtidigt finnas för sitt eget lidande. Det betyder att den egna sårbarheten avtäcks hos den profession som är på plats i sitt arbete för att ta del av en annan människas tillvaro och verklighet men även förnimma och hantera det som inte berättas eller verbaliseras. Essän begreppsliggör känsligheten uppmärksamheten och kärleken genom att söka och finna deras ursprung i antikens filosofi och idéerna om kärlek och kunskap. Därifrån går undersökandet till kärlek som en moralfilosofisk ide. Ur det arbetet förs tankar och de olika filosofernas funderingar in och prövar begreppet kärlek som ett praktiskt kunnande i psykoterapi. Att kärlek till klienter och kärlek till sig själv, möjligen är en praktisk kunskap. / This exploratory scientific essay aims to deepen and conceptualize a practical knowledge for a psychotherapist based on a story from a working day in her profession. An introductory quote by Nobel Laureate Olga Tokarczuk “Sensitivity as the most modest form of love (…)”, becomes the springboard of the essay which is then followed and whose meaning is woven together with the story. An overarching wonder at the essay’s departure is what the concept of sensitivity, attention and love has for the psychotherapist in her profession. Essentially, the texts of various philosophers, writers and poets and the story weave the practical knowledge, discernment and power of being the one who exists for another who suffers and at the same time exists for her own suffering. This means that one's own vulnerability is uncovered by the profession that is present in its work to take part of another person's existence and reality, but also to perceive and deal with what is not told or verbalized. The essay conceptualizes sensitivity to attention and love by seeking and finding their origin in ancient philosophy and the ideas of love and knowledge. From there, the study goes to love as a moral-philosophical idea. From that work, thoughts and the philosophers' ideas are brought in and tested for the concept of love as a practical knowledge in psychotherapy. That love for clients and love for themselves, possibly is a practical knowledge

Plato’s Symposium masterfully depicts several different explanations of the phenomenon of Eros or love. The physician Eryximachus depicts Eros as a cosmic force that can bring harmony to a number of areas, from medicine and music to astronomy and divination. Most readers of the Symposium have read Eryximachus in an unflattering way, as a pompous know-it-all who fails to give a speech that meets either his high aspirations or his high opinion of himself. In this paper I argue that this reading of Eryximachus and his speech is unpersuasive. My defense of Eryximachus has three components: (1) Plato treats Eryximachus sympathetically in the Symposium and elsewhere, and has him deliver a modest and perfectly coherent speech about the science of Eros. (2) Eryximachus’s speech can only be properly understood if we read it in the context of Hippocratic medical theory, which infuses the speech throughout. (3) Outside the Symposium, Plato views medicine as a model technē, and health as a central philosophical concept; inside the Symposium, Plato has his mouthpiece Socrates give a speech on behalf of the priestess Diotima that agrees with Eryximachus on nearly every point of his speech. This indicates that Plato would have viewed Eryximachus’s speech quite favorably, and that modern readers should follow suit. I conclude by suggesting how this reading of Eryximachus should influence how we read the Symposium as a whole. / text

This analysis of Keats's poem proffers evidence and arguments to support the contention that The Eve of St. Agnes presents allegorically the poet's speculations regarding the relationship between eros and agape, speculations which include a sharp criticism of Christianity and a model for a new, more "humanistic" system of salvation. The union of Madeline and Porphyro symbolizes the reconciliation of the two opposing types of love in an apocalyptic marriage styled on the Biblical union of Christ and the Church. The irony inherent in the poem arises from Keats's use of Christian myths, symbols, and sacraments to accomplish this purpose.

A luz solar apresenta ondas eletromagnéticas em ampla faixa espectral, incluindo as regiões do ultravioleta (UV-C, UV-B, UV-A), visível e infravermelho. Cada região interage com a pele de forma dependente da fotofísica e da fotoquímica dos seus respectivos compostos absorvedores. A luz UV-A causa a geração de espécies reativas de oxigênio e de nitrogênio (EROs e ERNs) através da fotossensibilização de moléculas endógenas (co-enzimas de flavina, porfirinas, melaninas). Quando fotossensibilizadores produzem quantidades de EROs e ERNs maiores do que a capacidade celular de supressão destas espécies, caracteriza-se um quadro de desbalanço redox, que causa lesão em biomoléculas como os ácidos nucleicos, lipídeos e as proteínas. Essas lesões podem levar à morte celular ou a outras transformações fenotípicas e genotípicas e também estimulam a liberação de citocinas pró-inflamatórias. Com a finalidade de melhor compreender a dinâmica dos mecanismos de resposta celular após exposição ao UV-A e ao visível, nós caracterizamos inicialmente as propriedades fotofísicas da melanina e detectamos a produção de oxigênio singlete (1O2) pela fotossensibilização no visível e a supressão desta espécie excitada pela reação do oxigênio singlete com a dupla ligação reativa dos grupos indóis presentes na melanina. Estes processos também foram observados no cabelo e levaram-nos a propor um modelo que explica o efeito da luz visível na estrutura e cor dos cabelos. Demonstramos também que a feomelanina produz mais (30%) 1O2 do que a eumelanina, que sofre maior modificação na sua estrutura por fotodegradação. O efeito destes processos na pele foi estudado a nível celular. Demonstramos que células epiteliais com maior teor de melanina apresentaram maior geração de 1O2 que causa lesão no DNA e morte necro-apoptótica após irradiação com luz visível. A foto-oxidação da melanina pela luz visível nos motivou a estudar um pigmento que fosse foto-protetor não somente contra luz UV-B mas também contra luz visível. A pigmentação com Acetil-Tirosina se mostrou atóxica e protetora contra luz UV-B e visível ao contrário do pigmento com tirosina, que se mostrou protetor do UV-B mas tóxico no visível. Este efeito foi relacionado com a localização celular do polímero e não com a estrutura do mesmo. A luz UV-A, por sua vez, promove o acúmulo de lipofuscina dentro dos vacúolos autofágicos de queratinócitos da pele e que também ativa a fototoxicidade pela luz visível. A lipofuscina dentro dos vacúolos autofágicos é foto-oxidada pela luz visível, causando lesão no DNA e morte celular programada tipo II. Doses UV-A que desencadeiam a liberação de citocinas também foram caracterizados. / Sunlight presents electromagnetic radiation over a wide spectral range, including the regions of ultraviolet (UV-C, UV-B, UV-A), visible and infrared. Each region interacts with skin dependending on the photophysics and photochemistry of the respective absorbing compounds. UV-A light causes the generation of reactive oxygen and nitrogen species (ROS and RNS) by photosensitization of endogenous molecules (flavin coenzymes, porphyrins, melanins). When photosensitizers produce amounts of ROS and RNS larger than the cell capacity to suppress these species, a set of redox imbalance, which damages biomolecules such as nucleic acids, lipids and proteins. This damage cause cell death and to other phenotypic and genotypic changes and also stimulates the release of proinflammatory cytokines. In order to better understand the dynamics of the mechanisms of cellular responses after exposure to UV-A and visible light, we initially characterized the photophysical properties of melanin and detected the production of singlet oxygen (1O2) by photosensitization in the visible, as well as the suppression of these excited species by reaction of singlet oxygen with the double bonds of the reactive groups presented in the melanin indols. These processes were also observed in hair and led us to propose a model that explains the effects of visible light on the structure and color of hair. We also demonstrated that pheomelanin produces more (30%) 1O2 than eumelanin, which undergoes a quick change on its structure by photodegradation. The effect of these processes in the skin was studied at the cellular level. We demonstrated that epithelial cells with larger melanin content have stronger generation of 1O2, which causes DNA damage and necro-apoptotic death after irradiation with visible light. The photo-oxidation of melanin by visible light has motivated us to study a pigment that was not only able to protect against UV-B but also against visible. Pigmentation with Acetyl-Tyrosine proved nontoxic and protective against UV-B and visible light instead of pigmentation with Tyrosine, which shielded against UV-B but showed toxicity in the visible. This effect was associated with the polymer, cell location and not with its structure. UV-A light, in turn, promotes the accumulation of lipofuscin, within autophagic vacuoles of keratinocytes also enabling phototoxicity in the visible light. The lipofuscin within the autophagic vacuoles is fotooxidized by visible light, causing DNA damage and programmed cell death type II. Linear dose of UV-A that trigger the release of cytokines were also characterized.

O status oxidativo do espermatozoide atua sobre ele de diferentes formas, desde a capacitação até a fecundação do oócito. No entanto, as espécies reativas de oxigênio (EROs) podem ser benéficas ou prejudiciais dependendo do contexto celular. Tendo em vista a baixa proteção antioxidante do sêmen criopreservado, associado às sucessivas manipulações que antecedem a fecundação in vitro, entender como esta célula se comporta em um ambiente oxidante e os impactos deste sobre o embrião é de suma importância. Com isto, o objetivo deste trabalho foi propor um modelo dose-dependente para o estudo do estresse oxidativo sobre o espermatozoide e possível impacto no desenvolvimento embrionário. Para isto, no experimento 1, palhetas de sêmen criopreservado de touros (n=5) da raça Nelore foram submetidas à incubação por 1 hora a 38,5 ºC e 5% CO2, com doses crescentes de peróxido de hidrogênio (0; 12,5; 25; e 50 µM). Ao final da incubação, os parâmetros de motilidade foram avaliados pelo sistema Computer Assisted System Analysis (CASA). No experimento 2, foram escolhidas duas doses de peróxido de hidrogênio com base nos resultados do experimento 1: alta (50 µM), baixa (12,5 µM) e também um controle (0 µM). Os espermatozoides foram incubados com as respectivas doses de peróxido de hidrogênio por 1 hora, e ao final da incubação foram utilizados para a fecundação in vitro (D=0). Neste experimento, além das análises do CASA, foram feitas avaliações do status oxidativo (CellROX® green e 2'-7'diacetato de diclorofluoresceína - DCFH), do potencial mitocondrial (JC-1), da cromatina (LA) e da capacitação espermática (clortetraciclina). Os embriões foram avaliados com relação à taxa de clivagem rápida (30 horas pós-inseminação), taxa de clivagem (D=3), taxa de desenvolvimento (D=5) e taxa de blastocisto (D=8). Para análise estatística foi utilizado o modelo de regressão polinomial, considerando p≤0,05. Tanto no experimento 1 quanto no experimento 2 houve detrimento dose-dependente do peróxido de hidrogênio sobre o padrão de movimento e de porcentagem de células móveis. Houve aumento dose-dependente da porcentagem de células positivas para CellROX® células capacitadas e positivas para o LA. Com relação às taxas de clivagem e de blastocisto, houve diminuição da porcentagem de embriões clivados e de blastocistos, conforme a dose de peróxido de hidrogênio foi aumentada. Referente à taxa de desenvolvimento embrionário, houve bloqueio das estruturas em 2-4 células. Nestas condições, o espermatozoide quando exposto a um ambiente oxidante, apresenta alterações no padrão de motilidade, no status oxidativo e na capacitação, sendo que estas interferem de forma negativa no desenvolvimento embrionário, desde o início da clivagem até a formação do blastocisto. / Oxidative status may influence spermatozoa by distinct mechanisms, from capacitation to oocyte fertilization. However, reactive oxygen species (ROS) could be beneficial or harmful depending on cellular context. Due to the low levels of antioxidant enzymes of cryopreserved semen, associated to successive manipulations prior to in vitro fertilization (IVF), it is momentous to understand the mechanism involved on sperm status in such conditions and the further impact on embryo development. The present study aimed to assess the possible impact of a dose-dependent model for sperm oxidative stress on embryo development. In experiment 1, straws from five Nelore bulls were subjected to a 1 hour incubation at 38,5 ºC and 5% CO2, with increase doses of hydrogen peroxide (0; 12,5; 25; e 50 &microM). At the end of incubation period, motility parameters were evaluated by Computed Assisted System Analysis (CASA). Based on the results of the experiment 1, experiment 2 was designed to study a high (50 µM) and a low (12,5 µM) dose of hydrogen peroxide and also a control (0 µM). Sperm samples were incubated with each dose for 1 hour and subsequently used for in vitro fertilization (D=0). Samples were analyzed by CASA, oxidative status (CellROX® green and 2'-7' diclorofluorescein diacetate - DCFH), mitochondrial potential (JC-1), chromatin (LA) and sperm capacitation status (chlortetraciclin). Embryos were evaluated based on fast cleavage rate (30 hours pos-insemination), cleavage rate (D=3), development rate (D=5) and blastocyst rate (D=8). Statistical analysis was performed by polynomial regression model, considering significant a p≤0,05. A dose-dependent deleterious effect of hydrogen peroxide was observed on most motility variables evaluated by CASA, including the percentage of motile cells. Similarly, a dose-dependent increase was observed on the percentages of positive cells for CellROX®, capacitated sperm and also for LA. A decrease on the percentage of cleaved embryos and blastocyst was observed as hydrogen peroxide increased. Interestingly, a blockage was detected during the 2-4 cell stage. In these conditions when exposed to oxidative environment, sperm may present disabled motility characteristics, oxidative status and premature capacitation and such abnormalities result on impaired embryo development, from the first cleavage to blastocyst.

Os genes relógio são responsáveis pelo ritmo circadiano e homeostase de diversos sistemas biológicos, incluindo o pâncreas endócrino. Nas células β são de grande importância para a regulação do metabolismo e da secreção de insulina (SI), e sua ausência pode levar ao desenvolvimento do diabetes. A NADPH oxidase (NOX) é um complexo enzimático responsável pela produção do ânion superóxido através da redução do oxigênio molecular. Em ilhotas pancreáticas, a NOX participa da regulação do metabolismo da glicose e da SI, através da modulação do estado redox intracelular. O objetivo do nosso estudo foi verificar se a desregulação dos genes relógio mediada pela ausência de Bmal1 seria capaz de modular a NOX e o estado redox nas células β pancreáticas, influenciando assim a SI. Observamos que a ausência de Bmal1 alterou a atividade e expressão da NOX, desregulando o estado redox intracelular. Essas alterações levaram à redução da viabilidade celular e mudanças na resposta à estimulação com glicose, resultando em uma deficiência na principal função da célula β a SI. / Clock genes are responsible for homeostasis and circadian rhythm in various biological systems, including endocrine pancreas. In β -cells, they are important for the regulation of metabolism and insulin secretion (IS), and its absence can lead to development of diabetes. NADPH oxidase (NOX) is an enzymatic complex responsible for production of superoxide anion by reducing molecular oxygen. In pancreatic islets, NOX regulates glucose metabolism and IS through modulation of the intracellular redox state. The aim of our study was to investigate whether dysregulation of clock genes mediated by Bmal1 suppression would be able to modulate NOX activity and redox state in pancreatic β cells, thus influencing the SI. In this work, the lack of Bmal1 altered the activity and expression of NOX, deregulating the intracellular redox state. These changes led to reduced cell viability and changes in cell response after stimulation with glucose, resulting in a deficiency in β cell main function, GSIS.