The genes that regulate pubertal timing in the general population are not well understood. Recently, genome-wide association studies have demonstrated that genetic variants near LIN28B associate with variation in pubertal timing in humans. To investigate where within the hypothalamic-pituitary-ovarian (HPO) axis Lin28b, and its homologue Lin28a, regulate pubertal timing, expression of these genes was assessed across the pubertal transition. The finding that Lin28a/b expression decreases only in the ovary suggests that the Lin28 pathway may exert its regulatory effects with respect to puberty in the ovary. Another aim of this thesis was to examine the effect of estrogen on Lin28b expression in immortalized GnRH neuronal cells, but the data remains equivocal and detailed future studies are needed to make definitive conclusions. The ovarian expression data lay the foundation for further studies using conditional knockout mice to verify the importance of the tissue and age specific developmental pattern that was identified.

The genes that regulate pubertal timing in the general population are not well understood. Recently, genome-wide association studies have demonstrated that genetic variants near LIN28B associate with variation in pubertal timing in humans. To investigate where within the hypothalamic-pituitary-ovarian (HPO) axis Lin28b, and its homologue Lin28a, regulate pubertal timing, expression of these genes was assessed across the pubertal transition. The finding that Lin28a/b expression decreases only in the ovary suggests that the Lin28 pathway may exert its regulatory effects with respect to puberty in the ovary. Another aim of this thesis was to examine the effect of estrogen on Lin28b expression in immortalized GnRH neuronal cells, but the data remains equivocal and detailed future studies are needed to make definitive conclusions. The ovarian expression data lay the foundation for further studies using conditional knockout mice to verify the importance of the tissue and age specific developmental pattern that was identified.

The slave trade across the Atlantic brought an estimated four million Africans to Brazil since the beginning of the XVI century until mid-XIX century, thus contributing to the significant miscegenation of Brazil s population. The current genetic condition is a result of the interbreeding process between the Native American (Amerindian), European populations and the African population. Presently, despite this population s elevated heterogeneity, small isolated groups can still be found, as is the case of the Quilombolas, who are the product of the resistant movement against slavery imposed by Portuguese colonization. With the objective of conducting research of the genetic composition and the origin of paternal lineages in nine Afro-descendent communities of Alagoas, Brazil, 15 Y-SNP markers were analyzed by applying the SNaPshot (Applied Biosystems) method. Utilizing the updated nomenclature of the Y-Chromosome Phylogenetic Tree, it was possible to identify nine haplogroups of the Y-Chromosome in a total of 209 individuals. The calculated genetic diversity ranged from 0.2000 to 0.7190, thus evidencing against a standardized composition of this population. As a result of patriarchal domination of the Portuguese economic model of colonization in Brazil, haplogroup R1b1b2*-M269, of European origin, was observed in all populations at a frequency of 5.26 - 79.17%. Haplogroup F*(xK)-M213 was found at a rate of 4.17% and 36.84%, suggesting an origin of European male ancestry in these individuals. Seven populations corresponded to haplogroup E1b1a1*-M2, of Sub-Saharan African descent, which presented a frequency above Alagoas population diversity, varying from 13.3% to 90.0%. However, Q1a3a*-M3, of the Amerindian group was observed in only 2 chromosomes. Sub-clades of Haplogroup E, of African descent, including E1b1b1b1*M81, E1b1b1a1*-M78 and E1b1b1c*-M123 were considerably frequent among the Portuguese. Applying AMOVA test, occurrences of heterogeneity among Alagoas Quilombola population (FST=0.23964, P=0,00000±0,00000) were verified, had a genetic intrapopulation variation of 23.96%. The study revealed no significant genetic variances between populations from Alagoas, Rio de Janeiro, Portugal and the Quilombola populations of Jacu, Palmeira dos Negros, Paus Pretos, Poços do Lunga and Carrasco. However, Cajá dos Negros, Muquém, Filus and Povoado Cruz presented distinct genetic constituents, thereby highlighting the hypothesis that the aforementioned communities were originally places of refuge for slaves. An analysis of hierarchies pertaining to Y-SNP markers improved the basis of knowledge of Afro-descendant populations in Alagoas, and in union with historical and anthropological facts and demographics, establishes itself as an important instrument in the field of population genetics. / O tráfico de escravos no Atlântico trouxe cerca de quatro milhões de africanos para o Brasil desde o início do século XVI até meados do século XIX, contribuindo para demasiada miscigenação da população brasileira. O cenário genético atual é resultante do processo de mistura entre a população nativa americana (ameríndios), as populações européias e de origem africana. Atualmente, apesar da elevada heterogeneidade desta população, pequenos grupos humanos isolados ainda podem ainda ser encontrados, como é o caso das populações remanescentes de quilombos, fruto da resistência ao regime escravista imposto na então colônia pelos portugueses. Objetivando estudar a composição genética e a origem das linhagens paternas em 9 comunidades afro descendentes de Alagoas, Brasil, foram analisados 15 marcadores Y-SNPs pelo método SNaPshot (Applied Biosystems), possibilitando a identificação de 9 haplogrupos do cromossomos Y em um total de 209 indivíduos, de acordo com a nomenclatura atualizada da Árvore Filogenética do Cromossomo Y. A estimativa de diversidade genética variou de 0,2000 a 0,7190, atestando não haver uniformidade na composição genética destas populações. De origem européia, o haplogrupo R1b1b2*-M269 foi observado em todas as populações, com frequências entre 5,26 - 79,17%, resultado da dominação patriarcal resultante do modelo econômico português de colonização do Brasil. O haplogrupo F*(xK)- M213 foi encontrado com frequências entre 4,17 e 36,84%, sugerindo origem européia aos ancestrais masculinos destes indivíduos. Sete populações apresentaram para o haplogrupo E1b1a1*-M2, de origem subsaariana, frequências acima das observadas na população miscigenada de Alagoas, variando entre 13,3% e 90,0%. Já Q1a3a*-M3, característico de ameríndios, foi observado apenas em 2 cromossomos. Foram observados ainda E1b1b1b1*-M81, E1b1b1a1*-M78 e E1b1b1c*-M123, ramos do haplogrupo E, de origem africana, porém apresentando frequências consideráveis entre os portugueses. Usando o teste de AMOVA, verificou-se a ocorrência de heterogeneidade entre as populações quilombolas de Alagoas (FST=0,23964, P=0,00000±0,00000), com variação genética interpopulacional de 23,96%. O estudo revelou não haver distâncias genéticas significativas entre as populações de Alagoas, Rio de Janeiro, Portugal e as populações quilombolas de Jacu, Palmeira dos Negros, Paus Pretos, Poços do Lunga e Carrasco, enquanto que Cajá dos Negros, Muquém, Filus e Povoado Cruz apresentam-se com distintas constituições genéticas, reforçando a hipótese de que estas comunidades foram originadas de locais de refúgio de escravos. As análises hierárquicas com marcadores Y-SNPs aprimoraram o conhecimento sobre as populações afro descendentes de Alagoas e, em conjunto com dados históricos, demográficos e antropológicos, constituem uma importante ferramenta na área da genética de populações.

Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal hematopoietic stem cell disorders with ineffective hematopoiesis. It is characterized by morphological dysplasia, peripheral cytopenias affecting one or more cell lineages and an increased risk of transformation into acute myeloid leukemia (AML). The early stages of MDS can be considered a premalignant disease. The pathogenesis of MDS has not been fully explained yet, but due to the development of molecular genetic and cytogenetic methods, the origin and development of the disease is gradually being elucidated. In addition to the cytogenetic changes that are part of the prognostic system (IPSS-R), the somatic mutations found in different genes come to the forefront of interest. However, they are not routinely used in clinical practice. One of the objectives of this study was monitoring of mutations in TP53 gene in lower-risk MDS patients who generally have a good prognosis and for whom these findings have a particularly relevant prognostic significance. We investigated a total of 154 patients with lower-risk MDS, and 13% of them had a mutation. After dividing patients according to the presence of del(5q), we observed significant differences in the incidence of the mutations. The mutations were detected in 23.6% of patients with...

nÃo hà / As raÃas de ovinos localmente adaptadas brasileiras, tambÃm conhecidas como nativas ou crioulas, descendem de animais trazidos durante o perÃodo colonial e, desde aquela Ãpoca, vÃm sendo submetidas a processos evolutivos sistemÃticos e nÃo sistemÃticos., o que resultou na formaÃÃo de genÃtipos altamente adaptados Ãs mais diversas condiÃÃes ambientais brasileiras. Embora estas raÃas nÃo possuam o mesmo potencial produtivo das raÃas exÃticas melhoradas, elas sÃo consideradas extremamente importantes devido Ãs relaÃÃes sociais e culturais que guardam com as populaÃÃes do campo. AlÃm disso, as raÃas localmente adaptadas possuem caracterÃsticas adaptativas importantÃssimas para a manutenÃÃo de sistemas produtivos tradicionais. A otimizaÃÃo da utilizaÃÃo dos recursos genÃticos naturalizados depende de um conhecimento profundo destas populaÃÃes e, portanto, a caracterizaÃÃo morfolÃgica, produtiva e molecular sÃo ferramentas imprescindÃveis para o sucesso da conservaÃÃo e utilizaÃÃo deste recurso genÃtico. Com base nisso, o objetivo desta tese foi aprofundar os estudos de caracterizaÃÃo molecular das principais raÃas de ovinos localmente adaptadas brasileiras: Crioula Lanada, Morada Nova e Santa InÃs. Assim, o capÃtulo I intitulado âIdentificaÃÃo de assinaturas de seleÃÃo em animais de produÃÃoâ consiste em uma revisÃo cujo objetivo à descrever os principais efeitos da seleÃÃo natural/artificial nos genomas das espÃcies de animais de produÃÃo, apresentar os principais mÃtodos de anÃlise de assinaturas de seleÃÃo e discutir os recentes avanÃos nesta Ãrea de estudo. Foram realizados dois estudos que resultaram nos capÃtulos II e III desta tese. O capÃtulo II, intitulado âIdentificaÃÃo de assinaturas de seleÃÃo em ovinos de raÃas localmente adaptadas brasileirasâ, teve como objetivo a identificaÃÃo e caracterizaÃÃo de regiÃes genÃmicas provÃveis de estar sob seleÃÃo nas trÃs principais raÃas brasileiras localmente adaptadas de ovinos e caracterizar estar regiÃes com a finalidade de identificar genes envolvidos com diferenÃas produtivas/adaptativas entre estas raÃas. A identificaÃÃo das regiÃes sujeitas à seleÃÃo foi feita com base em dois tipos de metodologia: diferenciaÃÃo entre populaÃÃes (FST) e desequilÃbrio de ligaÃÃo (iHS e Rsb). Foram identificados 78 genes candidatos envolvidos com funÃÃes como: resposta imune, desenvolvimento do sistema nervoso, percepÃÃo sensorial e desenvolvimento de pelos/lÃ. O capÃtulo III, intitulado: âIdentificaÃÃo de subestrutura de populaÃÃes em ovinos de raÃas localmente adaptadas brasileirasâ, teve como objetivos identificar e caracterizar a presenÃa de subestruturaÃÃo genÃtica dentro das trÃs principais raÃas brasileiras localmente adaptadas de ovinos. Foi observada, de uma forma geral, a presenÃa de diferenciaÃÃo genÃtica bastante considerÃvel ao comparar os rebanhos de cada raÃa analisada. AlÃm disso, tanto na raÃa Crioula Lanada quanto na raÃa Santa InÃs, pode ser observada a presenÃa de grupos bem distintos de indivÃduos, sugerindo a efetiva presenÃa de diferentes ecÃtipos/linhagens dentro destas raÃas. / The Brazilian locally adapted sheep breeds, also known as native and creole, are descendant from animals brought during the settlement period and, since then, are been subjected to evolutive (both systematic and non systematic) processes, what resulted in the formation of highly adapted genotypes to the diverse environmental Brazilian conditions. Although these breeds donât posses the same productive potential when compared with the exotic improved breeds, they are considered extremely important from a social and cultural point of view. Moreover, the locally adapted breeds are essential for the maintenance of traditional production systems. The optimization of the utilization of naturalized genetic resources depends on a deep knowledge of these populations, and then, the morphological, productive and molecular characterizations are essential to the success of conservation and utilization of these locally adapted genotypes. Therefore, the principal aim of this thesis was to deepen molecular the knowledge of the three main locally adapted Brazilian sheep breeds: Brazilian Creole, Morada Nova and Santa Ines. Thus, Chapter I entitled "Identification of selection signatures in livestock species" is a literature review that is proposed to describe the main effects of natural/artificial selection in the genomes of species of farm animals, present the main methods of signature selection analysis and discuss recent advances in this area of study. Two studies were conducted and resulted in the chapters II and III of this thesis. The chapter II, entitled âIdentification of selection signatures in brazilian locally adapted sheep breedsâ, aimed the identification and characterization of putative genomic regions that underwent selection and the identification of candidate genes related to productive/adaptative differences between these breeds. The identification of signatures of selection was performed through two approaches: population differentiation (FST) and linkage disequilibrium (iHS and Rsb). Seventy eight genes, related to functions as: immune response, nervous system development, sensorial perception and wool/hair development were identified. The chapter III, entitled âIdentification of population substructure in brazilian locally adapted sheep breedsâ, aimed the identification and characterization of of genetic substructure within the three main locally adapted Brazilian sheep breeds: Brazilian Creole, Morada Nova and Santa Ines. The level of genetic differentiation between herds of the same breeds was, in general, high. Both in the Brazilian Creole and in the Santa Ines breeds the presence of distinct groups on animals could be observed, what suggests the occurrence of different ecotypes/lineages within these breeds.

Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2017-05-09T19:16:43Z No. of bitstreams: 2 Tese - Adriana Maria Antunes Taquary - 2017.pdf: 3216713 bytes, checksum: caeaa4ba73b31eadb6f74040c4bb9b92 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-10T13:22:31Z (GMT) No. of bitstreams: 2 Tese - Adriana Maria Antunes Taquary - 2017.pdf: 3216713 bytes, checksum: caeaa4ba73b31eadb6f74040c4bb9b92 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-10T13:22:31Z (GMT). No. of bitstreams: 2 Tese - Adriana Maria Antunes Taquary - 2017.pdf: 3216713 bytes, checksum: caeaa4ba73b31eadb6f74040c4bb9b92 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In recent years there has been a rapid increase in the availability and quality of sequencing data and with this an explosion of projects of sequencing of the genomes of plants occurred. In this scenario, genomic analyzes have been characterized as efficient to generate genetic information on a large scale, including for non-model species. Dipteryx alata is a non-model tree species endemic to the Cerrado biome belonging to the Leguminosae family. The objectives of this work were to estimate the number of chromosomes and the size of the genome of D. alata, and also assemble and annotate sequences of the genomes organelles and nuclear of the species using Illumina sequencing data. The size of the genome of D. alata was estimated as 1C = 0.825 pg, which corresponds to a haploid genome of 807.2 MB with 2n = 16 chromosomes. Were assembled 275,709 nuclear genomic sequences with N50 equal to 1598, which corresponds to 355MB and 44% of the whole genome. In the nuclear sequences, 21,981 microsatellite regions were annotated, of which 49.3% had dinucleotide motifs, 42.7% trinucleotide motifs and 4% tetranucleotide motifs. Transposable elements (TEs) were found in 39.29% of the sequences analyzed, corresponding to 421,701 TEs. LTR retrotransposons (gypsy and copy) were the most abundant TEs in nuclear sequences. Were annotated 1,431 RNA genes non-translated into proteins, being 176 rRNAs, 189 tRNAs, 477 snRNAs, 8 snoRNAs, 466 miRNAs and 115 lncRNAs. Were annotated also 62,200 protein coding genes with an average size of 1,156 bp. The estimated number of mRNAs transcribed by the set of annotated nuclear genes was 160,450, of which 131,228 showed significant similarity with known sequences and 84,793 were classified functionally in the Gene Ontology terms. A total of 736,787 SNPs and 90,803 InDels were discovered in the nuclear sequences. A mean of 1 SNP was identified for each 189 bp of the genome and the ratio between the transition (Ts) and transversion (Tv) mutations was 1.58. A percentage of 46.5% of the SNPs occurs in the genic context and the effects of the SNPs were annotated mainly in exons and intergenic regions. Were assembled 110 KB of chloroplastid sequences with N50 of 2,384 bp and 327 KB of mitochondrial sequences with N50 of 1,784 bp. Were annotated genes of 3 rRNA, 13 tRNA, 6 miRNA and 20 lncRNA for the chloroplast and genes of 4 rRNA, 26 tRNA, 7 miRNA and 54 lncRNA for the mitochondria. For the chloroplast were predicted 20 protein coding genes with a mean size of 2,374 bp and for mitochondria were predicted 176 genes with a mean size of 1,279 bp. The estimated number of mRNAs transcribed by this gene set was 63 and 525 for chloroplast and mitochondria respectively. Were annotated 39 microsatellite regions and 4 TEs in the chloroplastid sequences and 158 microsatellite regions and 26 TEs in the mitochondrial sequences. This work, which can be considered one of the first genomic studies for Cerrado species, represents a great advance in the knowledge on the structure and organization of the D. alata genome. The obtained results open the way for further genetic and genomic investigation for the species. / Nos últimos anos houve um rápido aumento na disponibilidade e qualidade dos dados de sequenciamento e com isso ocorreu uma explosão de projetos de sequenciamento dos genomas de plantas. Nesse cenário, as análises genômicas vêm sendo caracterizadas como eficientes para gerar informações genéticas em larga escala, inclusive para espécies não modelos. Dipteryx alata é uma espécie de árvore não modelo endêmica do bioma Cerrado pertencente à família Leguminosae. Os objetivos deste trabalho foram estimar o número de cromossomos e o tamanho do genoma de D. alata, e também montar e anotar sequências dos genomas organelares e nuclear da espécie usando dados de sequenciamento Illumina. O tamanho do genoma de D. alata foi estimado como 1C = 0.825 pg, o que corresponde a um genoma haplóide de 807.2 MB com 2n=16 cromossomos. Foram montadas 275.709 sequências genômicas nucleares com N50 igual a 1598, o que corresponde a 355MB e 44% do genoma inteiro. Nas sequências nucleares foram anotados 21.981 regiões microssatélites, das quais 49,3% possuem motivos dinucleotídeos, 42,7% trinucleotídeo e 4% tetranucleotídeo. Elementos transponíveis (TEs) foram encontrados em 39,29% das sequências analisadas, o que corresponde a 421.701 TEs. Os retrotransposons LTR (gypsy e copia) foram os TEs mais abundantes nas sequências nucleares. Foram anotados 1.431 genes de RNAs não traduzidos em proteínas, sendo 176 rRNAs, 189 tRNAs, 477 snRNAs, 8 snoRNAs, 466 miRNAs e 115 lncRNAs. Foram anotados também 62.200 genes codificadores de proteínas com tamanho médio de 1.156 pb. O número estimado de mRNAs transcritos pelo conjunto de genes nucleares anotados foi igual a 160.450, dos quais 131.228 apresentaram similaridade significativa com sequências já conhecidas e 84.793 foram classificadas funcionalmente nos termos do Gene Ontology. Um total de 736.787 SNPs e 90.803 InDels foram descobertos nas sequências nucleares. Foi identificada uma média de 1 SNP a cada 189 pb do genoma e a razão entre as mutações de transição (Ts) e transversão (Tv) foi de 1,58. Uma porcentagem de 46,5% dos SNPs ocorreu em contexto gênico e os efeitos dos SNPs foram anotados principalmente em éxons e regiões intergênicas. Foram montados 110 KB de sequências cloroplastidiais com N50 de 2.384 pb e 327 KB de sequências mitocondriais com N50 de 1.784 pb. Foram anotados genes de 3 rRNA, 13 tRNA, 6 miRNA e 20 lncRNA para o cloroplasto e genes de 4 rRNA, 26 tRNA, 7 miRNA e 54 lncRNA para a mitocôndria. Para o cloroplasto foram preditos 20 genes codificantes de proteínas com tamanho médio de 2.374 pb e para a mitocôndria foram preditos 176 genes com tamanho médio de 1.279 pb. O número estimado de mRNAs transcritos por esse conjunto de genes foi igual a 63 e 525 para cloroplasto e mitocôndria, respectivamente. Foram anotados também 39 regiões microssatélites e 4 TEs nas sequências cloroplastidiais e 158 regiões microssatélites e 26 TEs nas sequências mitocondriais. Este trabalho, que pode ser considerado um dos primeiros estudos genômicos para espécies do Cerrado, representa um grande avanço nos conhecimentos sobre a estrutura e a organização do genoma de D. alata. Os resultados obtidos abrem caminho para novas investigações genéticas e genômicas para a espécie.

O eixo hipotálamo-pituitária-adrenal é o principal sistema neuroendócrino envolvido na regulação e adaptação da resposta ao estresse e, o principal hormônio secretado é o cortisol. O cortisol exerce seus efeitos por meio dos receptores mineralocorticoide (MR) e glicocorticoide (GR). Variações nos genes desses receptores têm sido associadas à sensibilidade aos glicocorticoides e mudanças no perfil metabólico. O objetivo geral desse trabalho foi compreender a variabilidade existente em relação às respostas fisiológicas de bovinos por meio da identificação de polimorfismos genéticos em genes envolvidos na resposta ao estresse e, verificar as consequências dessa variação genética em características de qualidade da carne. Dessa forma, três abordagens foram propostas: (1) avaliar a incidência de carne DFD (dark, firm and dry) e seu impacto no perfil metabólico, endócrino e características de qualidade da carne bovina, uma vez que o estresse é um dos principais fatores que levam a essa condição desfavorável; (2) avaliar a contribuição de fatores genéticos, por meio da identificação de polimorfismos de nucleotídeo único (SNPs), no gene do MR e GR, e suas associações com as características mensuradas; (3) avaliar os efeitos desses polimorfismos sobre o perfil proteico do músculo bovino. Foram utilizados 241 bovinos da raça Nelore. Os resultados evidenciaram implicações direta do pH 24 horas post-mortem nos atributos de cor e perdas por cozimento da carne. A incidência de carnes DFD (pH>=5,8) foi de 18,7%. Os polimorfismos identificados mostraram influenciar em algumas características mensuradas. Os SNPs NR3C2_1 e NR3C2_2 no gene do MR foram associados ao conteúdo de glicogênio muscular e nível plasmático do hormônio adrenocorticotrófico (ACTH) post-mortem, e o SNP NR3C1_1 no gene do GR foi associado aos níveis plasmático de cortisol post-mortem. As análises proteômicas demonstraram que a maioria das proteínas reguladas por esses SNPs estão envolvidas na contração muscular, metabolismo e defesa celular. Portanto, é possível inferir que o pH tem impacto nas características de qualidade da carne e que polimorfismos em MR e o GR levam a mudanças na atividade do eixo HPA, no perfil metabólico do organismo e no perfil proteico do músculo, sugerindo que esses genes estão envolvidos em uma complexidade de funções e podendo ser alvos de estudos em sistemas de produção que visam melhorar a produtividade. / The hypothalamic-pituitary-adrenal axis is the main neuroendocrine system involved in the regulation and adaptation in stress response and the primary hormone secreted is cortisol. Cortisol exerts its effects through the mineralocorticoid (MR) and glucocorticoid (GR) receptors. Variations in the genes of these receptors have been associated with sensitivity to glucocorticoids and changes in the metabolic profile. The general objective of this work was to understand the variability in relation to physiological responses of cattle through identification of genetic polymorphisms in genes involved in stress response and, checking the consequences of this genetic variation in meat quality traits. Thus, three approaches have been proposed: (1) evaluate the incidence of DFD meat (dark, firm and dry) and its impact on metabolics, endocrines profiles and meat quality traits, since stress is the major factor that lead to this unfavorable condition; (2) evaluate the contribution of genetic factors through identification single nucleotide polymorphisms (SNPs) in the MR and GR gene and its association with the measured traits; (3) evaluate the effects of these polymorphisms on the protein profile of bovine muscle. A total of 241 Nellore cattle were used. The results evidenced direct implications of 24 hours pH post-mortem in color attributes and cooking losses. The incidence of DFD meat (pH >= 5.8) was 18.7%. The polymorphisms identified demonstrated to influence some on measured characteristics. The NR3C2_1 and NR3C2_2 SNPs in MR gene were associated with muscle glycogen content and post-mortem adrenocorticotropic hormone (ACTH) plasma levels and, the NR3C1_1 SNP in GR was associated with post-mortem cortisol plasma levels. The proteomic analysis demonstrated that most proteins regulated by these SNPs are involved in muscle contraction, metabolism and cellular defense. Therefore, it is possible to infer that pH has impact on meat quality traits and MR and GR polymorphisms lead to changes in the HPA axis activity, metabolic profile and protein muscle profile, suggesting that these genes are involved in a complexity of functions and may be targets for studies on production systems to improve productivity.

Heart transplantation is performed in patients with end-stage heart failure, in whom all other methods of treatment failed. The most common causes of end-stage heart failure are dilated cardiomyopathy and coronary artery disease. The destiny of these patients is highly variable. Prediction of long term survival in patients after heart transplantation is not satisfactory and up to now has not been found reliable marker. Most of the patients die after heart transplantation due to cardiovascular disease. This thesis is focused on molecular genetics and statistical analysis of four single nucleotide polymorphisms, namely rs17817449 (16q12.2, FTO gene), rs2943634 (2q36.3; intergenic region), rs6922269 (6q25.1; MTHFD1L gene), and rs10757274 (9p21.3; intergenic region). According to genome wide association studies are these SNPs assosiated with cardiovascular diseases. We genotyped DNA samples of 364 heart donors and 364 heart recipients. The results were statistically compared (using OR and Pearson's χ2 test) with the control group, which consisted of samples of individuals from the general population MONICA study. We examined the genotype in patients whose hearts failed due to dilated cardiomyopathy or coronary artery disease and then in patients with cardiac allograft vasculopathy. Furthermore, we focused on...

O colágeno XVIII é um componente das membranas basais com diversos domínios funcionais, como a endostatina e o domínio frizzled, que têm importante papel em processos celulares como proliferação e diferenciação. COL18A1 possui dois promotores alternativos: o promotor 1, que regula a síntese da variante NC11-303, e o promotor 2 responsável pelas variantes NC11- 728 e NC11-493, expressas por hepatócitos. Existe uma variação interindividual da endostatina circulante e da expressão do colágeno XVIII no fígado. A expressão do colágeno XVIII/endostatina foi correlacionada com a progressão tanto do hepatocarcinoma (HCC), quanto da fibrose/cirrose hepática. Elucidar a regulação da expressão de COL18A1 pode auxiliar na compreensão dessa variação interindividual e da progressão dessas doenças. Neste trabalho demos início a caracterização do promotor 2 do COL18A1. Identificamos na seqüência predita como promotora cinco regiões conservadas entre humanos e camundongos. A análise in silico e funcional dessas regiões revelou que os fatores de transcrição, Sp1, Sp3, YY1, Oct-1, C/EBPα e C/EBPβ, interagem com as mesmas. Demonstramos que C/EBPβaumenta a taxa de transcrição do promotor 2 em hepatócitos, e que existe uma correlação positiva da expressão de NC11-493 com C/EBPαe C/EBPβem tecido hepático cirrótico e tumoral. As expressões de C/EBPαem tecido hepático cirrótico e tumoral estão diretamente correlacionadas, enquanto que os níveis de NC11-493 nos tumores estão inversamente correlacionados com o tamanho dos mesmos. Mostramos a existência de diversos SNPs no promotor 2. O SNP-700T/G, funcional in vitro, afeta a interação de Sp3 e YY1 com essa região regulatória. A deleção da região do SNP indicou que ela possui elementos importantes para a transcrição em hepatócitos, apesar deste SNP não estar relacionado com o nível de expressão do colágeno XVIII em fígado fibrótico ou com susceptibilidade a HCC. O SNP- 700T/G está em desequilíbrio de ligação com o SNPc.1135C/T, no domínio frizzled do colágeno XVIII. Não foi possível elucidar a funcionalidade do SNPs c.1135C/T in vitro, mas os haplótipos formados por esses dois SNPs têm diferentes frequências entre descendentes de europeus e de africanos. Nosso trabalho traz importantes contribuições e abre novas perspectivas para a compreensão da regulação do colágeno XVIII em fígado humano, tanto em situações fisiológicas, quanto em processos fibrogênicos e tumorigênicos¶ / Collagen XVIII is a basal membrane component with several funcional domains, such as endostatin and frizzled domains, which have important roles in cellular processes such as proliferation and differentiation. COL18A1 has two promoter regions: promoter 1, that regulates the synthesis of NC11-303 isoform, and promoter 2, localized in intron 2, responsible for NC11-728 and NC11-493 isoforms expressed by hepatocytes. There is a large interindividual variation in circulating endostatin and in collagen XVIII liver expression. Collagen XVIII/endostatin levels were correlated with hepatocellular carcinoma (HCC) progression, as well as liver fibrosis/cirrhosis, conditions that precede HCC. Elucidating the mechanisms that regulate COL18A1 expression in hepatocytes may help understanding its variation among individuals and liver disease stages, as well as contribute to new treatment strategies. In this work we began to characterize COL18A1 promoter region 2. We identified in the predicted promoter sequence five conserved regions between human and mouse. The in silico and functional analysis of these regions revealed that transcription factors Sp1, Sp3, YY1, Oct-1, C/EBPα and C/EBPβ interact with them. We have demonstrated that C/EBPβ increases promoter 2 transcription rate in hepatocytes, and that there is a positive correlation of NC11-493 expression with that of C/EBPα and C/EBPβ in cirrhotic and tumor liver samples. Non-tumor and tumor C/EBPα expressions positively correlate between themselves, while NC11-493 tumor expression inversely correlates with tumor size. We also showed that there are several SNPs in COL18A1 promoter 2 region. SNP-700T/G, functional in vitro, affects Sp3 and YY1 interaction with the promoter 2 region and deletion of the SNP region indicated that this sequence has important hepatocyte regulatory elements. Our results suggest that this SNP does not significantly affects COL18A1 expression in fibrotic/cirrhotic liver and is not associated with HCC susceptibility. SNP-700T/G is in linkage disequilibrium with SNPc.1135C/T, at collagen XVIII frizzled domain. We could not elucidate SNPc.1135C/T functionality in vitro, but the haplotypes formed by these two SNPs have different frequencies in European and African descendants. In conclusion, our work brings important contributions and opens new perspectives for the comprehension of collagen XVIII regulation in human liver in physiological situations, as well as in fibrotic/cirrhotic and tumorigenic process.

>Magister Scientiae - MSc / The burden of non-communicable diseases (NCDs) in South Africa is predicted to increase substantially in the next decades if the necessary preventative measures are not taken. The two most common NCDs associated with rapid mortality increase are diabetes mellitus (DM) and hypertension (HTN). Both of these diseases, i.e DM and HTN, can be a result of a combination of modifiable risk factors (behavioral) and non-modifiable risk factors (genetic, physiological, and environmental). New strategies implemented to manage these diseases should include addressing both modifiable and non-modifiable risk factors for patients with NCDs. The aim of this study was to contribute to the reduction of incidence of uncontrolled T2DM among patients taking metformin as a first-line anti-diabetic drug, through the development of individualized therapy for this drug. When implemented, this could be one of the healthcare strategies to address non-modifiable risk factors for patients with T2DM as an important NCD. The first objective of the study was to explore the prevalence and risk factors of DM and HTN in South Africa, especially within the economically disadvantaged population.