Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-14T11:12:13Z No. of bitstreams: 1 468517 - Texto Completo.pdf: 6892081 bytes, checksum: c5aa659f71c5093d831d4810c3ab482c (MD5) / Made available in DSpace on 2015-05-14T11:12:13Z (GMT). No. of bitstreams: 1 468517 - Texto Completo.pdf: 6892081 bytes, checksum: c5aa659f71c5093d831d4810c3ab482c (MD5) Previous issue date: 2014-08-27 / The understanding of gene function in the externally visible characteristcs (EVC) expression has several uses in human population evolution studies or in forensic investigations. To this last, some effort has been done to discover an efficient and easy model for prediction of skin and eye color in humans. The obvious advantage of the prediction of such EVCs through the use of DNA is to be incorporated as routine in forensic labs and to be applied to police investigations. In our study we combined the genotyping of eight SNPs in pigment-related genes (rs4778138 - OCA2; rs12913832 - HERC2; rs16891982 - SLC45A2; rs8045560 - MC1R; rs1426654 - SLC24A5; rs2733832 - TYRP1; rs1042602 - TYR; rs916977 - HERC2) with different analytical approaches. Considering this SNP panel we evaluated allele frequencies from HAPMAP and ALFRED data obtained from subjects with High Melanin Content (HMC; from African populations), and Low Melanin Content (LMC; from European populations) and defined the alleles H (to predict HMC subjects) and alleles L (to predict LMC subjects). The cumulative distribution of alleles H and alleles L in two phenotypically different color groups of 134 South Brazilian subjects showed that 82% of HMC subjects (N = 61) had eight or more allele H and 100% of LMC subjects (N = 73) had less than eight allele H, with accuracy value of 96.3%. We performed other analyses using AUC (Area Under the Receiver Operating Characteristic Curve), PGL (Calculation of Pathway Genetic Load), and GP (Genetic Probability) approaches. The AUC was 0.99 in predicting both HMC and LMC phenotypes; PGL showed the eight SNPs panel had 93% of concordance between genotype and HMC or LMC phenotypes; and GP approach showed 91% of concordance between prediction and HMC or LMC phenotypes. Our high-throughput genotyping technology combined with different analytical approaches reached very high accuracy to predict the extreme phenotypes of human pigmentation. We believe this forensic DNA phenotyping (FDP) technique would be particularly useful in cases in which the genetic profiles of crime scenes were not found in the DNA data banks or to help classify degraded cadavers skeletons, or biological clues of dismissed people. / A compreens?o da fun??o e express?o dos genes envolvidos nos tra?os externamente vis?veis (EVC; do ingl?s externally visible characteristics) t?m sido amplamente utilizada em v?rios estudos de evolu??o humana e investiga??es forenses. Para este ?ltimo prop?sito, v?rios esfor?os t?m sido feitos para descobrir um modelo eficiente e f?cil para a predi??o da cor da pele e dos olhos em seres humanos. A vantagem ?bvia da predi??o de tais EVCs, atrav?s da utiliza??o do DNA, ? sua incorpora??o na rotina em laborat?rios forenses, sendo assim aplicada em investiga??es policiais. Em nosso estudo, relacionamos o gen?tipo de oito SNPs em genes relacionados com a pigmenta??o (rs4778138 - OCA2; rs12913832 - HERC2; rs16891982 - SLC45A2; rs8045560 - MC1R; rs1426654 - SLC24A5; rs2733832 - TYRP1; rs1042602 - TYR; rs916977 - HERC2) com diferentes abordagens anal?ticas. Este painel de SNPs considerou as frequ?ncias al?licas obtidas de dados do HapMap e Alfred a partir de indiv?duos com Alto Conte?do de Melanina (HMC; do ingl?s High Melanin Content; a partir de popula??es africanas), e Baixo Conte?do de Melanina (LMC; do ingl?s Low Melanin Content; a partir de popula??es europeias) e definiu os alelos H (para predizer os HMC) e alelos L (para predizer os LMC). A distribui??o cumulativa dos alelos H e L nos dois grupos com caracter?sticas de pigmenta??o fenotipicamente distintas, dos 134 indiv?duos da nossa popula??o, mostrou que 82% dos indiv?duos HMC (N = 61) tinham oito ou mais alelos H e 100% dos indiv?duos de LMC (N = 73) tinham menos de oito alelo H, com o valor de precis?o de 96,3%. Outras abordagens como AUC (do ingl?s; Area Under the Receiver Operating Characteristic Curve), c?lculo de PGL (do ingl?s; Pathway Genetic Load) e GP (do ingl?s; Genetic Probability) foram realizadas. A an?lise AUC foi de 0,99 tanto para a predi??o fenot?pica dos HMC quanto LMC; as an?lises PGL, para o painel com 8 SNPs, teve 93% de concord?ncia gen?tipo-fen?tipo nos HMC ou LMC; e a abordagem GP mostrou 91% de concord?ncia para predi??o dos fen?tipos HMC e LMC. Nossa tecnologia de genotipagem de alto rendimento, combinada com diferentes abordagens anal?ticas, chegou a uma precis?o muito alta para predizer os fen?tipos extremos de pigmenta??o humana. Acreditamos que esta t?cnica de fenotipagem forense pelo DNA (FDP; do ingl?s forensic DNA phenotyping), seria particularmente ?til nos casos em que os perfis gen?ticos de locais de crime n?o fossem encontrados no bancos de dados de DNA ou para ajudar a classificar cad?veres degradados, esqueletos, ou vest?gios biol?gicos de pessoas desaparecidas.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-15T12:04:15Z No. of bitstreams: 1 468567 - Texto Completo.pdf: 3711593 bytes, checksum: 32dee061e07f3464cbf1a35564001f4c (MD5) / Made available in DSpace on 2015-05-15T12:04:15Z (GMT). No. of bitstreams: 1 468567 - Texto Completo.pdf: 3711593 bytes, checksum: 32dee061e07f3464cbf1a35564001f4c (MD5) Previous issue date: 2014-08-22 / Eucalyptus is an economically important woody species, especially as a raw material in many industrial sectors. Brazil ranks the second worldwide position in acreage, totalizing approximately three million hectares. Eucalyptus species are very susceptible to pathogens such as Botrytis cinerea (gray mold), which leads to mortality of cuttings in rooting phase. Biological control of plant diseases using soil microorganisms has been considered an alternative to reduce the use of pesticides and pathogen attack. Plant growth promoting rhizobacteria can act directly on plant development for production of phytohormones or indirectly as antagonists to pathogens, as well as promote changes in secondary metabolism, and hence inducing of systemic resistance. In this study, the direct roleof Streptomyces isolates in plant development was evaluated through the production of auxin and rhizogenic potential in Eucalyptus grandis and E. globulus plants, as well as indirectly, by modulation of the secondary metabolism, and induction of sistemic resistence in plantselicited with Streptomyces sp. and challenged with the pathogenic fungus B. cinerea. Metabolic responses were evaluated throughactivity of plant defense enzymes (PPO and POX) and induced secondary compounds (total phenolics and quercetinic-flavonoids fraction). The incidence and progression of gray mold disease on plants elicited Streptomyces sp. PM9, and coculture of these microorganisms (Streptomyces and B. cinerea) were also evaluated. Streptomyces sp. PM5 and PM9 isolates produced more auxin than the other isolates tested. Streptomyces sp. PM9 showed the highest rhizogenic potential on Eucalyptus sp. and modulated secondary metabolism of these plants. Antagonism of this isolated over B. cinerea was evidenced. Plants elicited with Streptomyces sp. PM9 and challenged with B. cinerea showed changes in PPO and POX enzymes and levels of phenolic compounds at different time points of analysis, which may be related to initial defense response. Phenolic compounds chlorogenic acid and gallic acid were, on average, the most abundant, while caffeic acid, benzoic acidand catechin were induced at specific time points. A delay in the onset of disease was significant in plants of E. grandis elicited with Streptomyces. The induction of resistance, disease delay and antagonism against B. cinereaindicate the capacity of Streptomyces sp. PM9 as an inducer of plant systemic resistance, and poses this microorganism as a potential candidate for biological control programs in nurseries of Eucalyptus. Interaction of rhizobacteria with eucalyptus plant, as well as the modulation of defense mechanisms may contribute to the establishment of new biocontrol strategies applied to forestry. / O eucalipto ? uma esp?cie lenhosa economicamente importante, destacando-se como mat?riaprima em diversos setores industriais. O Brasil ocupa a segunda posi??o mundial em ?rea plantada, totalizando aproximadamente tr?s milh?es de hectares. As esp?cies de eucalipto s?o muito suscet?veis a pat?genos como Botrytis cinerea (mofo-cinzento), o qual leva ? mortalidade de estacas em fase de enraizamento. O controle biol?gico de doen?as em plantas utilizando microrganismos do solo tem sido considerado uma alternativa para reduzir o uso de agroqu?micos e o ataque de pat?genos. Rizobact?rias promotoras de crescimento vegetal podem agir diretamente no desenvolvimento das plantaspela produ??o de fitorm?niosou indiretamente, como antagonistas a fungos patog?nicos, al?m de causar altera??es no metabolismo secund?rio, com consequente indu??o de resist?ncia sist?mica. Neste trabalho, avaliou-se a a??o direta no desenvolvimento vegetal de isolados rizobacterianos do g?nero Streptomyces atrav?s da produ??o de auxinas e potencial rizog?nico de Eucalyptus grandis e E. globulus, bem como oefeito modulador no metabolismo secund?rioe a indu??o de resist?ncia sist?mica em plantas eliciadas com Streptomyces sp. e desafiadas com o fungo patog?nico B. cinerea. As respostas metab?licas foram avaliadas atrav?s das atividades de enzimas realacionadas ? defesa vegetal (PPO e POX) e dos compostos secund?rios induzidos (compostos fen?licos totais e fra??o flavon?ides quercet?nicos). A incid?ncia e progress?o da doen?a mofo cinzento em plantas eliciadas com Streptomyces sp. PM9, e cocultivo destes microrganismos (Streptomyces e B.cinerea) tamb?m foram avaliados. Os isolados de Streptomycessp.PM5 e PM9 apresentaram maior produ??o de auxina que os demais isolados testados. Streptomyces sp.PM9 apresentou o maior potencial rizog?nico em plantas de Eucalyptus sp. emodulou o metabolismo secund?rio destas plantas. Oantagonismo deste isolado sobre B. cinerea foi evidenciado.As plantas eliciadas com Streptomyces sp. PM9 e desafiadas com B. cinereaapresentaram altera??es nas enzimas PPO e POXe nos n?veis de compostos fen?licos totais em diferentes tempos de an?lise, as quais foram relacionadas ? resposta inicial de defesa.Os compostos fen?licos ?cido g?lico e clorog?nico foram, em m?dia, os mais abundantes, embora os ?cidos cafeico e benzoico e a catequina tenham sido induzidos em momentos espec?ficos. O retardo no estabelecimento da doen?a foi significativo em plantas de E. grandis eliciadas com Streptomyces. Os resultados de indu??o de resist?ncia, retardo da doen?a eantagonismocontra B.cinerea, demonstram a capacidade de a??o de Streptomycessp. PM9 como indutor de resist?ncia sist?mica vegetal, colocando este microrganismo como potencial candidato aos programas de controle biol?gico em viveiros de mudas de Eucalyptus. A intera??o da planta de eucalipto com a rizobact?ria, bem como a modula??o dos mecanismos de defesa podem contribuir para o estabelecimento de novas estrat?giasde biocontrole aplicado ? silvicultura.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-18T11:58:07Z No. of bitstreams: 1 468720 - Texto Completo.pdf: 6747791 bytes, checksum: dc8f03c538738774e24f74700ad72365 (MD5) / Made available in DSpace on 2015-05-18T11:58:07Z (GMT). No. of bitstreams: 1 468720 - Texto Completo.pdf: 6747791 bytes, checksum: dc8f03c538738774e24f74700ad72365 (MD5) Previous issue date: 2015-03-03 / New animal models for neurodegenerative diseases study are necessary for the knowledge of molecular mechanisms and behavioral patterns involved on the progression of dementias as Alzheimer?s Disease (AD) as well as for new therapies development. We characterized four neurodegenerative approaches including: (1) ?-amyloid(1-42) peptide injection, one of the hallmark proteins of patients with AD. In this model, we observed that intra-ventricular brain injection of ?-amyloid soluble oligomers in 24hpf embryos caused an increase in tau phosphorylation followed by cognitive deficits at 5dpf, both results being reversed by Lithium treatment, a tau kinase (GSK-3?) inhibitor. (2) The inhibition of exon 8 splicing of Presenilin-1, protein responsible for the Amyloid Precursor Protein (APP) cleavage, was achieved using Morpholino oligonucleotides. This approach caused a dysfunction of Presenilin-1, characteristic of patients with the familiar form of AD, that disturbed cognitive behavior and caused morphological phenotype similar to the ones observed by modifications of Notch pathway. We also developed two transgenic animals, (3) one overexpressing through a heat-shock promoter the ?-amyloid protein. These animals when exposed to a temperature of 37?C activate the heat-shock protein expression and as a consequence amyloid-? protein, one of the hallmark proteins of AD. The second transgenic animal (4) we knocked-out the Appb gene using TALEN as a genetic manipulation technic. This model will provide a better understanding of Appb function during animal development and AD progression. Those four animal models include features suggesting that, when used separately or in combination, can hereafter elucidate those pathways interactions and clarify the cellular and molecular mechanism associated with cognitive deficits during Alzheimer?s disease progression. With these models we were able to characterize zebrafish as a potential animal model, not just for understanding the role of those proteins over neurodegenerative process, but also on their normal functions in the system. Besides that, zebrafish have been used for a few years in pharmacological tests, and the development of animal models for Alzheimer?s disease as ours, make this animal a robust model for development of new treatments for this and other diseases. / Novos modelos para o estudo de doen?as neurodegenerativas s?o necess?rios para a caracteriza??o dos mecanismos moleculares e comportamentais envolvidos na progress?o de dem?ncias como a Doen?a de Alzheimer (DA), al?m de serem importantes para a identifica??o de novos alvos com potencial terap?utico. Aqui caracterizamos quatro abordagens neurodegenerativas incluindo: (1) A inje??o do pept?deo ?-amil?ide(1-42), uma dos principais pept?deos alterados em pacientes com DA. Neste modelo observamos que a inje??o de olig?meros sol?veis de ?-amil?ide no ventr?culo cerebral de embri?es de 24hpf causou um aumento na fosforila??o da prote?na tau em res?duos de est?gios iniciais da DA acompanhados por d?ficit cognitivo aos 5dpf, ambos revertidos pelo tratamento com L?tio, inibidor da enzima GSK-3? que fosforila tau. (2) Realizamos tamb?m a inibi??o do splicing do ?xon 8 da prote?na Presenilina-1, membro do complexo gama-secretase que ? respons?vel pela clivagem da Prote?na Precursora do Amil?ide (APP), atrav?s do bloqueio com oligonucleot?deos Morfolinos. Esta abordagem causou uma altera??o na funcionalidade da Presenilina-1, caracter?stica de pacientes com a forma familiar da DA, comprometendo a cogni??o dos animais e ocasionando altera??es morfol?gicas similares ?s causadas pela modifica??o da via Notch. Tamb?m realizamos a produ??o de dois animais transg?nicos, o primeiro (3), superexpressando a prote?na ?-amil?ide atrav?s de um promotor heat-shock. Estes animais quando expostos a uma temperatura de 37?C ativam a express?o das prote?nas heat-shock e por consequ?ncia a express?o da prote?na ?-amil?ide, que como dito anteriormente ? uma das principais altera??es em pacientes com a DA. O segundo (4), inibindo a express?o da APP atrav?s da t?cnica de manipula??o gen?tica utilizando TALEN. Este ultimo modelo ir? fornecer informa??es importantes sobre a participa??o desta prote?na durante desenvolvimento e a progress?o da DA. Estes quatro modelos abrangem caracter?sticas que sugerem que, quando usados separadamente ou em combina??o, poder?o contribuir tanto na elucida??o de mecanismos celulares e moleculares associados a d?ficits cognitivos quanto nas intera??es destas vias com a DA. A possibilidade de desenvolver modelos complementares com abordagens diversas em um mesmo organismo confirma o potencial do zebrafish n?o s? para o entendimento da participa??o destas prote?nas no processo neurodegenerativo mas tamb?m em suas fun??es normais no sistema nervoso.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-20T12:50:04Z No. of bitstreams: 1 469018 - Texto Completo.pdf: 1309740 bytes, checksum: 2aed89fbf06476e1b1522282c9325099 (MD5) / Made available in DSpace on 2015-05-20T12:50:04Z (GMT). No. of bitstreams: 1 469018 - Texto Completo.pdf: 1309740 bytes, checksum: 2aed89fbf06476e1b1522282c9325099 (MD5) Previous issue date: 2015-02-18 / The ethanol exposure during early embryonic development can cause morphological and behavioral changes even when ingested in low doses. Growth retardation, microcephaly and mental retardation are some of the features observed in children with FAS (fetal alcohol syndrome) whose mothers ingested ethanol during pregnancy. The mechanisms by which ethanol affects embryonic development and cause such changes have not been fully elucidated. The increase in the extracellular adenosine levels after chronic and acute exposure to ethanol indicates that the purinergic system has an important role in this situation. Adenosine is a neuromodulator that acts through the activation of metabotropic receptors type P1 (A1, A2A, A2B and A3) and can act as an endogenous neuroprotector. In the extracellular space, adenosine can be produced by sequential hydrolysis of adenosine triphosphate (ATP) held by ectonucleotidases, a cascade of a family of enzymes located on the cell surface, which the key process to hydrolyze to adenosine is performed by ecto-5'-nucleotidase. The use of zebrafish in toxicology studies and development offers a number of advantages. Its size and breeding allow the maintenance of a large quantity of fish in a relatively small space. The production of a large number of eggs and the development occurs rapidly, and progresses through well-defined steps. Recent studies have employed the zebrafish as a model for fetal alcohol syndrome and demonstrated that embryonic exposure to ethanol results in phenotypes comparable to those observed in other vertebrate models. The objective of this study was to evaluate the role of adenosine metabolism in the morphological and locomotor parameters of zebrafish larvae exposed to ethanol. The results showed that in addition to morphological damage already known, there is a change in the enzymatic activity of ecto-5'-nucleotidase in larvae of seven days, in both treatments, acute and chronic, independent of gene expression form, which in time was not changed. Pre-treatment with AOPCP, an inhibitor of ecto-5'- nucleotidase, was unable to prevent the morphological damage in a relevant way, although statistically there was a slight prevention. Pre-treatment with dipyridamole, an adenosine transport blocker further worsened the effects caused by ethanol. Considering the changes that occur in extracellular levels of adenosine after exposure to ethanol and the involvement of the purinergic system in early stages of development, our results suggest that there is a combined action of the enzyme ecto-5'-nucleotidase and nucleoside transporters in this rising of extracellular adenosine levels, with emphasis on the inhibition of nucleoside transporters. Additionally, we can infer that there is a correlation between elevated levels of adenosine and morphological defects after exposure to ethanol. These results suggest that the purinergic system is a target for the toxic effects induced by ethanol in the early stages of development. / A exposi??o ao etanol durante as fases iniciais de desenvolvimento embrion?rio pode causar altera??es morfol?gicas e comportamentais, mesmo quando ingerido em baixas doses. Retardo no crescimento, microcefalia e retardo mental s?o algumas das caracter?sticas observadas em crian?as portadoras da SAF (s?ndrome alco?lica fetal), cujas m?es ingeriram etanol durante a gesta??o. Os mecanismos pelos quais o etanol afeta o desenvolvimento embrion?rio e causa tais altera??es ainda n?o foram completamente desvendados. O aumento extracelular da adenosina ap?s exposi??es cr?nicas e agudas ao etanol indica que o sistema purin?rgico tem um importante papel nesses mecanismos. A adenosina ? um neuromodulador que atua atrav?s da ativa??o de receptores metabotr?picos do tipo P1 (A1, A2A, A2B e A3) e pode agir como um neuroprotetor end?geno. No espa?o extracelular, a adenosina pode ser produzida pela hidr?lise sequencial da adenosina trifosfato (ATP) realizada pela cascata das ectonucleotidases, uma fam?lia de enzimas localizada na superf?cie celular, sendo o processo chave ? hidr?lise da adenosina monofosfato (AMP) ? adenosina ? realizada pela ecto-5?- nucleotidase. A utiliza??o do peixe-zebra em estudos toxicol?gicos e de desenvolvimento oferece uma s?rie de vantagens. Seu tamanho e a forma de cria??o permitem a manuten??o de uma grande quantidade de peixes em um espa?o relativamente pequeno. O cruzamento resulta em um grande n?mero de ovos e o desenvolvimento ocorre rapidamente, e progride atrav?s de etapas bem definidas. Estudos recentes t?m empregado o peixe-zebra como modelo para a s?ndrome alco?lica fetal e demonstrado que a exposi??o embrion?ria ao etanol resulta em fen?tipos compar?veis com aqueles observados em outros modelos vertebrados. O objetivo deste estudo foi avaliar o papel do metabolismo da adenosina nos par?metros morfol?gicos e locomotores de larvas de peixe-zebra expostas ao etanol. Os resultados obtidos demonstraram que al?m dos danos morfol?gicos j? conhecidos, h? altera??o na atividade enzim?tica da ecto- 5?-nucleotidase em larvas de 7 dias, em ambos os tratamentos, agudo e cr?nico, de uma forma independente da express?o g?nica, que por sua vez, n?o foi alterada. O tratamento pr?vio com AOPCP, um inibidor da ecto-5?-nucleotidase, n?o foi capaz de prevenir os danos morfol?gicos de forma relevante, embora estatisticamente verificou-se uma leve preven??o. O pr?-tratamento com dipiridamol, um bloqueador do transporte de adenosina, piorou ainda mais os efeitos causados pelo etanol. Considerando as mudan?as que ocorrem nos n?veis extracelulares de adenosina ap?s exposi??es ao etanol e o envolvimento do sistema purin?rgico em est?gios iniciais do desenvolvimento, nossos resultados sugerem que existe uma a??o combinada da enzima ecto-5?-nucleotidase e dos transportadores de nucleos?deos nesta eleva??o dos n?veis extarcelulares de adenosina, com ?nfase na inibi??o dos transportadores de nucleos?deos. Adicionalmente, podemos inferir que h? uma correla??o entre a eleva??o dos n?veis de adenosina e os defeitos morfol?gicos caracter?sticos da exposi??o ao etanol. Tais resultados sugerem que o sistema purin?rgico ? um alvo para os efeitos t?xicos induzidos pelo etanol nas fases iniciais do desenvolvimento.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-06-19T11:36:44Z No. of bitstreams: 1 470792 - Texto Completo.pdf: 1695613 bytes, checksum: bfea5d57cf26d524d5b14d7d3ac84cdc (MD5) / Made available in DSpace on 2015-06-19T11:36:44Z (GMT). No. of bitstreams: 1 470792 - Texto Completo.pdf: 1695613 bytes, checksum: bfea5d57cf26d524d5b14d7d3ac84cdc (MD5) Previous issue date: 2014-03-12 / Melanoma is one of the most aggressive malignant tumors, and its incidence has been increasing steadily in recent years. Usually in the early stages, treatment for melanoma is local surgery with reasonable efficiency. However, treatments such as chemotherapies for advanced melanoma have limited benefits, prolonging the patient's life in a few months. Thus the search for more effective therapies for melanoma is necessary. More recent studies suggest that tumor immune response conducted by subtypes of CD4+ T helper cells subsets have an important role in cancer control. According to tumor infiltrating Th17 and Treg cellsand the cytokines they secrete the tumor microenvironment profile may be suggested anti or pro-tumor activities or exerted by these cells. In this study, we investigated the transcriptional markers of CD4+Foxp3+ T cells and CD4+ROR?t+ T cells in draining lymph nodes of animals throughout the melanoma tumor growth and evaluate whether the combined action of cisplatin (cis-diamino-dichloro-platin, CDDP) and TLR2 (peptidoglycan) or TLR3 (acid-Polyribosilic Polyribocytidilic) or TLR4 (lipopolysaccharide) agonists, can change these parameters. The animals were injected with melanoma cell line B16F10 and according tumor progression the tumor draining lymph node (TDLN) were excised for analysis of Treg and Th17 cells by flow cytometry. Furthermore, we analyzed the survival of animals treated with combined therapies. We found an increase in the percentage and absolute number of Th17 and Treg cells in TDLN according tumor progression, which was consistent with previous studies. Our results indicate that treatment with cisplatin promotes tumor growth by increasing Treg and Th17 cells. Treatment with CDDP plus TLR2 agonist significantly decreases the percentage of Th17 cells in TDLN. We demonstrated here, that combinated CDDP and TLR3 or TLR4 agonist therapy impairs tumor growth and modulate the frequency of these cells by decreasing the percentage of CD4+Foxp3+ T cells. In addition, this combination also showed a modest increase insurvivalof the melanoma bearing mice. These results showed that TLRs agonists may be used in combination with cisplatin as a potential adjuvant capable impair tumor growth in melanoma bearing mice. / Melanoma ? um dos tumores malignos mais agressivos, e sua incid?ncia vem aumentando continuamente nos ?ltimos anos. Geralmente em est?gios iniciais, o tratamento para melanoma ? local, por cirurgia, com razo?vel efic?cia. Contudo, os tratamentos para melanoma em est?gios avan?ados por quimioterapia t?m benef?cios limitados, prolongando a vida do paciente em poucos meses. Assim se faz necess?ria a busca por terapias mais efetivas para melanomas. Estudos mais recentes sugerem que a resposta imunol?gica tumoral realizada pelos subtipos de c?lulas T CD4+ auxiliares possuem papel importante no controle do c?ncer. Conforme o infiltrado tumoral de c?lulas Th17 e Treg e o perfil de citocinas que elas secretam no microambiente tumoral, pode-se sugerir atividades anti ou pr?-tumorais exercidas por essas c?lulas. Neste estudo, n?s investigamos os marcadores transcricionais de c?lulas T CD4+Foxp3+ e c?lulas T CD4+ROR?t+ em linfonodos drenantes de animais com melanoma ao longo do crescimento tumoral e avaliamos se a a??o combinada de cisplatina (cis-diamino-dichloro-platin, CDDP) com agonistas de TLR2 (Peptidoglicano) ou TLR3 (?cido Polyribosilic-Polyribocytidilic) ou TLR4 (Lipopolissacar?deo) podem alterar esses par?metros. Os animais foram injetados com c?lulas de melanoma linhagem B16F10 e conforme a progress?o tumoral os linfonodos drenantes tumorais (TDLN) foram excisados para an?lise de c?lulas Th17 e Treg por citometria de fluxo. Al?m disso, analisamos a sobrevida dos animais com a a??o combinadas das terapias. Encontramos um aumento na porcentagem e n?mero absoluto de c?lulas Th17 e Treg no TDLN conforme a progress?o tumoral o qual foi condizente com estudos anteriores. Nossos resultados indicam que o tratamento apenas com cisplatina, promove o crescimento tumoral atrav?s do aumento de c?lulas Th17 e Treg. O tratamento de cisplatina com agonista de TLR2 diminui consideravelmente a porcentagem de c?lulas Th17 no TDLN. Demonstramos aqui que a combina??o de terapias utilizando CDDP juntamente com agonistas de TLR3 ou TLR4, prejudica o crescimento tumoral e pode modular a frequ?ncia dessas c?lulas atrav?s da diminui??o na porcentagem de c?lulas TCD4+Foxp3+. Adicionalmente, essa combina??o tamb?m mostrou um modesto aumento na sobreviv?ncia dos animais. Esses resultados mostram que agonistas de TLRs podem ser utilizados em combina??o com cisplatina como potencial adjuvante capaz de induzir inibir o crescimento tumoral em modelo de melanoma murino.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-07-21T11:30:34Z No. of bitstreams: 1 472476 - Texto Completo.pdf: 2364616 bytes, checksum: c4b022cfc35016dfceaaa75088b36bcb (MD5) / Made available in DSpace on 2015-07-21T11:30:34Z (GMT). No. of bitstreams: 1 472476 - Texto Completo.pdf: 2364616 bytes, checksum: c4b022cfc35016dfceaaa75088b36bcb (MD5) Previous issue date: 2014-11-21 / Crack is a cocaine-??derived substance that acts as a stimulant of the central nervous system. It is characterized by low cost, quick action and high power dependency. Little is known about effects at the cellular level caused by the crack and body resilience of body during period of abstinence. Studies have shown an increased production of reactive oxygen species (ROS) after administration of cocaine. Oxidative stress occurs when there is an imbalance between the production of ROS and the ability of the antioxidant defense in combat or prevent its action. This condition can be harmful to cells, causing damage to biomolecules such as DNA, lipids and proteins. Aiming to better understand the action of crack and abstinence in redox state, this study enrolled thirty patients of program for detoxification and thirty volunteers who did not use drugs taken as control group. Blood samples were collected after 4th and the 18th day of treatment and plasma was used for biochemical analysis. Quantifications were performed oxidants markers such as protein carbonyl and protein thiols, both demonstrate protein modifications by ROS, and antioxidant markers such as glutathione peroxidase and superoxide dismutase and non-??enzymatic markers such reduced glutathione (GSH) and total reactive antioxidant potential (TRAP).Psychological variables were assessed through the scores obtained Cocaine Selective Severity Assessment, Fagerstrom Tolerance Questionnaire, Beck Depression Inventory version II (BDI-??II) and Addiction Severity Index. After four days of abstinence we observe observed an increase in oxidative markers compared to end of the treatment. After eighteen days of abstinence there is a recovery of antioxidant defenses. Also, we observed e a positive correlation between protein carbonyls and psychological variables and a negative correlation between the levels of TRAP levels and psychological variables. Thus, our results suggest that abstinence period may provide a recovery of antioxidant defenses, thereby reducing propensity for oxidative damage. / O crack ? uma subst?ncia derivada da coca?na que age como estimulante do sistema nervoso central. ? caracterizado pelo baixo custo, r?pida a??o e alto poder de depend?ncia. Pouco se sabe sobre os efeitos a n?vel celular causados pelo crack e sobre a capacidade de recupera??o do organismo no per?odo de abstin?ncia. Estudos tem demonstrado uma eleva??o da produ??o de esp?cies reativas de oxig?nio (EROS) ap?s a administra??o da coca?na. O estresse oxidativo ocorre quando h? um desequil?brio entre a produ??o de EROS e a capacidade do sistema de defesa antioxidante em combater ou prevenir sua a??o. Essa condi??o pode ser nociva para as c?lulas, causando danos a biomol?culas como DNA, lip?deos e prote?nas. Com o objetivo de melhor compreender a a??o do crack e da abstin?ncia no sistema de defesa antioxidante e no dano oxidativo, esse estudo recrutou trinta volunt?rias pacientes de um programa para desintoxica??o e trinta volunt?rias que n?o faziam uso de drogas tidas como grupo controle. Amostras de sangue foram coletadas ap?s o 4? e o 18? dia de tratamento e o plasma foi utilizado para as an?lises bioqu?micas. Foram realizadas quantifica??es de marcadores oxidantes, como prote?nas carboniladas e ti?is proteicos, ambos demonstram modifica??es proteicas feitas por EROS e marcadores antioxidantes, tanto enzim?ticos como glutationa peroxidase e super?xido dismutase quanto n?o enzim?tico como glutationa reduzida (GSH) e o potencial antioxidante reativo total (TRAP).As vari?veis psicol?gicas foram avaliadas atrav?s dos escores obtidos nos question?rios: Cocaine Selective Severity Assessment, Question?rio de Toler?ncia de Fagerstrom, Invent?rio de Depress?o de Beck vers?o II (BDI-??II) e o Addiction Severity Index. Ap?s o 4? dia de abstin?ncia observamos um aumento dos marcadores oxidantes em compara??o ao fim do tratamento. Ap?s dezoito dias de abstin?ncia h? uma recupera??o das defesas antioxidantes. Tamb?m evidenciamos uma correla??o positiva entre as prote?nas carboniladas e vari?veis psicol?gicas e uma correla??o negativa entre os n?veis de TRAP e as vari?veis psicol?gicas. Dessa forma, nossos resultados sugerem que o per?odo de abstin?ncia pode propiciar uma recupera??o das defesas antioxidantes, diminuindo assim, a propens?o ao dano oxidativo.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-07-21T11:43:47Z No. of bitstreams: 1 472479 Texto Completo.pdf: 1633754 bytes, checksum: 4a4e4307d99c258ef92fc1b916f00e9e (MD5) / Made available in DSpace on 2015-07-21T11:43:47Z (GMT). No. of bitstreams: 1 472479 Texto Completo.pdf: 1633754 bytes, checksum: 4a4e4307d99c258ef92fc1b916f00e9e (MD5) Previous issue date: 2015-03-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Potato is currently the third most consumed food crop after rice and wheat, and it is a valuable resource for alleviating poverty in undeveloped countries. However, potato crop fields are attacked by numerous pests and pathogens, which represent a threat to the global potato production. Unlike animals, plants do not possess an adaptive immune system. Therefore, each individual plant cell needs to be able to perceive the pathogen, release signals to neighbor cells, and produce a defense response. Plant cells recognize the pathogen through Pattern Recognition Receptors (PRRs), triggering a signaling cascade that results in the activation of defense-related genes, which characterize the occurrence of Systemic Acquired Resistance (SAR). Among the factors involved in the regulation of defense-related genes, salicylic acid is widely known as an elicitor of plant defense against biotrophic pathogens.Besides this hormone, it has been demonstrated that a bacterial extract of Xanthomonas axonopodis pv. citri (referred to as XTH) is capable of inducing resistance against pectolytic bacteria via poorly understood mechanisms. Considering the different signaling pathways involved in plant defense, we intended to investigate the occurrence of systemic resistance in Solanum tuberosum plants treated with XTH or salicylic acid, by analyzing the expression of PR-1b, PR-2, ChtA, PAL, Pin2, JAZ1/TIFY10A, and ERF1 genes. Our results suggest that XTH is capable of inducing systemic resistance in potato plants via concomitant activation of the salicylic acid, jasmonic acid, and ethylene signaling pathways. / A batata ? atualmente o terceiro alimento mais consumido no mundo, depois do arroz e do trigo, al?m de ser um recurso importante no combate ? fome em pa?ses subdesenvolvidos. Entretanto, plantas de batata s?o atacadas por diversas pragas e pat?genos, que representam uma amea?a ? produ??o global de tub?rculos. Ao contr?rio dos animais, as plantas n?o possuem um sistema imune adaptativo. Dessa forma, as plantas dependem que cada c?lula, individualmente, tenha a capacidade de perceber o pat?geno, sinalizar ?s c?lulas vizinhas e produzir uma resposta de defesa. As c?lulas vegetais percebem o contato do pat?geno atrav?s de Receptores de Reconhecimento de Padr?es (PRRs), desencadeando cascatas de sinaliza??o que levam ? ativa??o de genes de defesa, os quais caracterizam a ocorr?ncia de Resist?ncia Sist?mica Adquirida (SAR). Dentre os fatores envolvidos na regula??o de genes relacionados ? defesa, o ?cido salic?lico ? amplamente conhecido como um eliciador da defesa vegetal contra pat?genos biotr?ficos.Al?m deste horm?nio, foi demonstrado que o extrato bacteriano de Xanthomonas axonopodis pv. citri (denominado de indutor XTH) possui a caracter?stica de induzir resist?ncia contra fitobact?rias pectol?ticas atrav?s de mecanismos ainda pouco conhecidos. Considerando as diferentes vias de sinaliza??o envolvidas na defesa vegetal, pretendeu-se investigar a ocorr?ncia de resist?ncia sist?mica em plantas de Solanum tuberosum tratadas com indutor XTH ou ?cido salic?lico, atrav?s da an?lise transcricional dos genes PR-1b, PR-2, ChtA, PAL, Pin2, JAZ1/TIFY10A e ERF1. Os resultados sugerem que o indutor XTH tem a capacidade de induzir resist?ncia sist?mica em plantas de batata atrav?s da ativa??o concomitante das vias de sinaliza??o do ?cido salic?lico, jasmonato e etileno.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-08-25T11:42:48Z No. of bitstreams: 1 474060 - Texto Completo.pdf: 1372189 bytes, checksum: a43c7ff8c9402604b61dba9bcef89a8f (MD5) / Made available in DSpace on 2015-08-25T11:42:48Z (GMT). No. of bitstreams: 1 474060 - Texto Completo.pdf: 1372189 bytes, checksum: a43c7ff8c9402604b61dba9bcef89a8f (MD5) Previous issue date: 2015-03-18 / The potato is the third most important consumed food in the world. Despite its high productivity, many pest problems cause losses in the quantity and quality of the product. Its high susceptibility to pathogens such as the necrotrophic bacteria Pectobacterium atrosepticum, has led to the indiscriminate use of pesticides, causing damage to the environment and human population. Studies of plant resistance inducers represent an alternative for disease control in some cultures by promoting innate defense system against pathogens. Understanding the changes in plant metabolism related to defense enables the evaluation and development of new strategies and products to disease control. This work aimed was to evaluate some of the mechanisms involved in defense metabolism of Solanum tuberosum in response to the phytobacteria Pectobacterium atrosepticum as well as to the XTH and ASM elicitors.To this end, we analyzed the activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APx), enzymes related to defense metabolism, polyphenol oxidase (PPO), peroxidase (POX), phenylalanine ammonia lyase (PAL), and pathogenesis-related proteins, ?-1,3-glucanase and chitinase. It was also determined the synthesis of phenolic compounds and salicylic acid (SA), and the assessment of disease progression caused by the phytobacteria in leaves pretreated with XTH. Our results showed that the elicitor XTH was able to delay the disease progression and symptoms caused by the bacteria P. atrosepticum.The elicitors ASM and XTH promoted the activation of the antioxidant enzymes, as well as the induction of certain enzymes related to defense before and after the bacterial inoculation, differing from the response pattern observed in the leaves treated only with P. atrosepticum. In addition, we observed an increase in free SA levels in leaves treated only with the phytobacteria, differing from the other treatments. In conclusion, the elicitor XTH promotes resistance to the necrotrophic bacteria P. atrospeticum by the defense metabolism activation and modulation of S. tuberosum. / A batata destaca-se como o terceiro alimento mais consumido no mundo. Apesar de sua alta produtividade, in?meros problemas fitossanit?rios v?m causando perdas na quantidade e na qualidade do produto. Sua alta suscetibilidade a pat?genos, como a bact?ria necrotr?fica Pectobacterium atrosepticum, tem levado ao uso indiscriminado de agrot?xicos, causando danos ao meio ambiente e ? popula??o humana. Estudos com indutores de resist?ncia vegetal t?m representado uma alternativa para o controle de doen?as em algumas culturas atrav?s da promo??o do sistema inato de defesa contra pat?genos. Compreender as modifica??es no metabolismo vegetal relacionado ? defesa possibilita a avalia??o e o desenvolvimento de novos recursos e produtos para o manejo fitossanit?rio.Este trabalho teve por objetivo avaliar alguns dos mecanismos envolvidos no metabolismo de defesa de Solanum tuberosum em resposta ? fitopabact?ria Pectobacterium atrosepticum e aos indutores XTH e ASM. Para tal, foram realizadas an?lises de atividade das enzimas antioxidantes super?xido dismutase (SOD), catalase (CAT) e ascorbato peroxidase (APx), das enzimas relacionadas ao metabolismo de defesa, polifenoloxidase (PPO), peroxidase (POX), fenilalanina am?nia liase (PAL), e das prote?nas relacionadas ? pat?genese, ?-1,3-glucanase e quitinase. Foi determinado tamb?m o ac?mulo de compostos fen?licos e de ?cido salic?lico (AS), al?m da avalia??o da manifesta??o da doen?a provocada pela fitobact?ria em folhas pr?-tratadas com XTH. Os resultados demonstraram que o indutor XTH foi capaz de retardar a progress?o e os sintomas da doen?a provocados pela bact?ria P. atrosepticum em folhas de batata.Os indutores XTH e ASM promoveram a ativa??o das enzimas antioxidantes, assim como a indu??o de enzimas relacionadas ? defesa, anteriormente e posteriormente ? inocula??o de P. atrosepticum, diferindo do padr?o de resposta observado nas folhas tratadas apenas com a bact?ria patog?nica. Al?m disso, foi observado um aumento dos n?veis de AS livre nas folhas tratadas apenas com a fitobact?ria, diferindo dos outros tratamentos. A partir destes resultados conclui-se que o indutor XTH promove resist?ncia contra a bact?ria necrotr?fica P. atrospeticum atrav?s da ativa??o e modula??o do metabolismo de defesa em S. tuberosum.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-10-02T11:49:35Z No. of bitstreams: 1 475296 - Texto Completo.pdf: 1059884 bytes, checksum: dfe493d659fd6e13b6ac8c1bcc09a9aa (MD5) / Made available in DSpace on 2015-10-02T11:49:35Z (GMT). No. of bitstreams: 1 475296 - Texto Completo.pdf: 1059884 bytes, checksum: dfe493d659fd6e13b6ac8c1bcc09a9aa (MD5) Previous issue date: 2015-02-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Funda??o de Amparo ? Pesquisa do Estado do Rio Grande do Sul - FAPERGS / Neonatal exposure to lipopolysaccharides (LPS) generates a stressful stimulus capable of affecting the development of important systems, which causes lasting behavioral and neuroendocrine alterations. The aim of this study is to evaluate the response to an inflammatory stimulus in Balb/c mice exposed to LPS-induced neonatal stress at different ages and genders. Mice underwent intraperitonial injections on postnatal days 3 and 10 with either LPS (100ug/Kg) or saline solution. After 21 or 60 days of age, either saline solution was injected or an inflammatory stimulus was induced by the injection of 1% carrageenan. Inflammatory cytokines, reactive oxygen species and NETs production were measured in the peritoneal lavage. Our findings indicate that LPS-induced neonatal stress can reduce inflammatory cytokines in young animals, males and females. In adults, however, only females showed the same response pattern. In nLPS group, an increase in NETs production was observed in animals that were 60-days-old when compared to 21-days-old in both genders, which indicates an effect of neonatal stress on the ontogeny of NETs formation. The production of ROS was not affected by neonatal stress, even though an increased production was found among adults regardless of neonatal intervention. The results shown here indicate that LPS-induced neonatal stress can alter cytokine production in response to inflammatory stimuli at different ages, in a gender dependent way. Moreover, it seems like the formation of NETs throughout life is also influenced by alterations undergone during the neonatal period. / A exposi??o neonatal ao lipopolissacar?deo (LPS) gera um estimulo estressor capaz de afetar o desenvolvimento de importantes sistemas, dando origem a altera??es comportamentais e neuroend?crinas duradoras. O objetivo desta disserta??o ? avaliar a resposta a um est?mulo inflamat?rio em camundongos Balb/c submetidos ? estresse neonatal por LPS em diferentes idades e sexos. Os camundongos receberam, no 3? e 10? dias de vida, inje??o i.p. de LPS (100?g /Kg) ou solu??o salina. Ap?s 21 ou 60 dias de vida, os mesmos foram submetidos ? inje??o de solu??o salina ou a um est?mulo inflamat?rio atrav?s da inje??o de carragenina 1%. Foram mensurados no lavado peritoneal citocinas inflamat?rias, esp?cies reativas de oxig?nio e produ??o de Redes Extracelulares de Neutr?filos (NETs). Os resultados encontrados demonstram que o estresse neonatal por LPS diminui a libera??o de citocinas inflamat?rias nos animais jovens machos e f?meas. J? nos adultos, somente as f?meas apresentaram a mesma resposta. Foi encontrado um aumento na produ??o de NETs nos animais do grupo nLPS com 60 dias quando comparado com animais nLPS com 21 dias, em ambos os sexos, indicando um efeito do estresse neonatal sobre a ontogenia da forma??o de NETs. A produ??o de ROS n?o sofreu influ?ncia do estresse neonatal, por?m foi encontrada uma maior produ??o na idade adulta, independente da interven??o neonatal. Os resultados do presente estudo indicam que o estresse neonatal por LPS altera a produ??o de citocinas em resposta a um est?mulo inflamat?rio em diferentes idades, em um efeito dependente do sexo. Al?m disso, parece que a forma??o de NETs ao longo da vida tamb?m ? influenciada pelas altera??es no per?odo neonatal.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-10-26T11:19:38Z No. of bitstreams: 1 475882 - Texto Completo.pdf: 18258562 bytes, checksum: 5b76b66a03e3116f7e13505a183443a8 (MD5) / Made available in DSpace on 2015-10-26T11:19:38Z (GMT). No. of bitstreams: 1 475882 - Texto Completo.pdf: 18258562 bytes, checksum: 5b76b66a03e3116f7e13505a183443a8 (MD5) Previous issue date: 2015-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The major depressive disorder (MDD) is a psychiatric condition which profoundly alters with the brain metabolism and neurochemistry characterized by a state of deep, chronic sadness, accompanied by anhedonia, sensation of worthlessness and lack of motivation, often leading the patient to suicide. The ventral tegmental area (VTA) is an important dopaminergic region intimately associated with the pathophysiology of MDD. Ketamine is a drug that antagonizes the glutamatergic NMDA receptors which has been shown to exert an immediate antidepressant effect and the treatment with ketamine is a promising new alternative for MDD therapeutic. Furthermore, the small animal positron emission tomography (microPET) is a technique which allows the assessment of the temporal-spatial distribution of radiolabelled molecules in vivo, and the utilization of 18F-Fluorodeoxyglucose (18F-FDG) as a radiotracer for this analysis still needs standardization in our University. In this sense, this thesis has been divided into two stages. Firstly, we standardized the brain metabolic assessment technique using 18F-FDG associated with microPET in Wistar rats, and with it, we rendered a neurometabolic atlas of the distribution of 18F-FDG in 56 brain regions. We compared our neurometabolic data with data from five other scientific articles which assessed the biochemical and immunohistochemical activity of cytochrome c oxidase (COX), these techniques are traditionally used for assessment of ex vivo brain metabolism. Thus, we ranked the regions analyzed in our study and the regions from the selected COX studies, and correlated the rankings with the Spearman test for non-parametric ranked data correlation. In this study we detailed the distribution of 18F-FDG in the brain of Wistar rats. On four of the selected studies we did not find a correlation, only on Shumake at al.?s study we found a moderate correlation (r=0.56, p=0.023). In the second stage, we analyzed the influence of acute ketamine treatment on the depressive-like behavior, the glucose metabolism and tyrosine hydroxylase activity (TH) (a rate-limiting dopamine synthesis enzyme) in the VTA of animals exposed to the chronic unpredictable stress (CUS). In this study, 48 Wistar rats were divided into four groups: 1-Control, 2-Ketamine, 3-CUS, 4-CUS+Ketamine. The animals undergone the CUS protocol were expose to several stressors, twice-daily, for 28 consecutive days. The treatment consisted of a single intraperitoneal injection of 10mg/kg of ketamine. For the behavioral analysis the sucrose preference test, the open field test, and the forced swim test were executed. The glucose metabolism and TH immunoreactivity in the VTA were analyzed by 18F-FDG-microPET and immunohistochemistry for TH, respectively. The CUS groups showed a decrease in sucrose solution intake and an increase in the immobility time on the forced swim test, and ketamine treatment was able to reverted the depressive-like behavior (p<0.05. The CUS protocol and ketamine treatment did not influence upon the 18F-FDG uptake or the TH immunoreactivity in the VTA. The results obtained in this thesis aid on the standardizing of the use of 18F-FDG with microPET, for the analyses on brain metabolism in our university. Furthermore, with the CUS protocol, we confirmed the acute, antidepressant effect of ketamine, however, our finds indicated that this effect is not related to metabolic or dopaminergic physiology in the VTA. / O transtorno depressivo maior (MDD) ? um dist?rbio psiqui?trico que altera profundamente a neuroqu?mica e o metabolismo encef?lico; caracterizado clinicamente por um estado de tristeza profunda cr?nica, acompanhada por anedonia, sensa??o de desvalia e falta de motiva??o, podendo levar o paciente a cometer suic?dio. A ?rea tegmental ventral (VTA) ? uma importante regi?o dopamin?rgica intimamente relacionada com a patofisiologia do MDD. A cetamina ? um f?rmaco antagonista de receptores NMDA glutamat?rgicos que apresenta um r?pido efeito antidepressivo e o tratamento agudo com cetamina ? uma promissora alternativa terap?utica para os pacientes com MDD. Ademais, a tomografia por emiss?o de p?sitrons para pequenos animais (microPET) ? uma t?cnica que permite avaliar a distribui??o temporal-espacial de mol?culas radiomarcadas in vivo, e a utiliza??o do 18F-Fluorodeoxiglicose (18F-FDG) como r?dio-tra?ador para este tipo de an?lise ainda necessita ser padronizada junto a nossa Universidade. Deste modo, esta tese de doutorado foi dividida em duas etapas. Primeiramente, padronizamos a t?cnica de an?lise do metabolismo encef?lico de ratos Wistar com uso de 18F-FDG associada ao microPET, e com isso confeccionamos um atlas neurometab?lico detalhado da distribui??o de 18F-FDG em 56 regi?es encef?licas. Comparamos os dados neurometab?licos obtidos com dados de cinco artigos da literatura cient?fica que realizaram avalia??es bioqu?micas e imunoistoqu?micas da atividade do citocromo c oxidase (COX), t?cnicas tradicionalmente utilizadas para an?lise do metabolismo encef?lico ex vivo. Para a compara??o, ordenamos as regi?es analisadas em nosso estudo e as regi?es dos estudos de COX selecionados, ent?o correlacionamos estas ordena??es atrav?s do teste n?o param?trico de correla??o para dados ordenados de Spearman. Neste estudo detalhamos a distribui??o de 18F-FDG no enc?falo de ratos Wistar. Em quatro dos estudos selecionados n?o encontramos correla??o, somente com o estudo de Shumake et al. encontramos uma correla??o moderada (r=0,56, p=0,023). Na segunda etapa, analisamos a influ?ncia do tratamento agudo com a cetamina sobre o comportamento s?mil-depressivo, o metabolismo de glicose e a atividade da enzima tirosina hidroxilase (TH) (uma enzima limitante na s?ntese de dopamina) na VTA de animais submetidos protocolo de estresse cr?nico imprevis?vel (CUS). Neste estudo, 48 ratos Wistar foram divididos em quatro grupos: 1-Controle, 2-Cetamina, 3-CUS, 4-CUS+Cetamina. Os animais submetidos ao protocolo CUS foram expostos a estressores variados, duas vezes ao dia, por 28 dias consecutivos. O tratamento foi uma ?nica administra??o intraperitoneal de 10mg/kg de cetamina. Para an?lise comportamental foram realizados os testes de prefer?ncia a sacarose, campo aberto e nado for?ado. O metabolismo da glicose e a imunorreatividade para TH na VTA foram analisadas por meio do 18F-FDG-microPET e imunoistoqu?mica para TH, respectivamente. Os grupos CUS apresentaram uma diminui??o do consumo de solu??o de sacarose e um aumento no tempo de imobilidade no teste de nada for?ado e o tratamento com cetamina foi capaz de reverter o comportamento s?mil-depressivo (p<0,05). O protocolo CUS e o tratamento com cetamina n?o exerceram influ?ncia sobre a capta??o de 18F-FDG e a imunorreatividade para TH na VTA. Os resultados obtidos com esta tese de doutorado possibilitaram a padroniza??o do uso de 18F-FDG com microPET, para an?lise do metabolismo encef?lico de ratos Wistar em nossa Universidade. Ademais, com o uso do protocolo CUS, confirmou-se o efeito antidepressivo agudo da cetamina, contudo nossos achados indicam que este n?o ? relacionado a altera??es metab?licas ou da histofisiologia dopamin?rgica da VTA.