Orientadores: Shirlei Maria Recco Pimentel, Ana Cristina Prado Veiga Menocello / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-12T03:22:49Z (GMT). No. of bitstreams: 1 Duarte_ThiagoCellin_M.pdf: 1944479 bytes, checksum: 814f8a0a8bd0078b0f432679c3115819 (MD5) Previous issue date: 2008 / Resumo: O gênero Pseudopaludicola, atualmente pertencente à família Leiuperidae, é formado por 12 espécies amplamente distribuídas pela América do Sul, com nove delas relatadas para o Brasil. Com base em dados morfológicos, as espécies do gênero foram alocadas em dois grupos: "pusilla" e "falcipes". Mudanças taxonômicas freqüentes foram relatadas para o gênero e análises recentes com base em dados moleculares mostraram que as relações intergenéricas de Pseudopaludicola também permanecem pouco esclarecidas. Devido à grande semelhança morfológica dos exemplares de Pseudopaludicola, há suspeita de confusões na identificação das espécies para algumas localidades e da existência de espécies novas. De modo geral, existem poucas informações citogenéticas para o gênero que, em sua maioria, se restringem à determinação do número de cromossomos e análise do cariótipo por método de coloração convencional. Considerando que a análise citogenética mais detalhada constitui uma ferramenta importante que pode contribuir para a diferenciação de espécies de Pseudopaludicola e para o entendimento da sistemática do gênero, no presente trabalho foram estudadas as espécies Pseudopaludicola mineira, P. canga e P. saltica, provenientes de suas localidades-tipo (Serra do Cipó, MG; Serra dos Carajás, PA; e Chapada dos Guimarães, MT, respectivamente), P. saltica de Uberlândia, MG, Pseudopaludicola aff. saltica de Rio Claro (SP), Pseudopaludicola aff. falcipes de Icém (SP), e outras três amostras de Pseudopaludicola sp. (1, 2 e 3) provenientes, respectivamente, de Andaraí (BA), Barreirinhas (MA) e Uberlândia (MG). As metáfases foram obtidas de suspensões de células de epitélio intestinal e de testículo, e coradas com Giemsa ou submetidas às técnicas impregnação por prata (Ag-NOR) para detecção de região organizadora de nucléolo (NOR) e de bandamento C, para a localização de heterocromatina. As espécies estudadas dividem-se em dois grupos quanto ao número de cromossomos, 2n=18 e 2n=22. As espécies P. mineira, Pseudopaludicola sp.1, P. saltica e Pseudopaludicola aff. saltica apresentam 2n=22 cromossomos. Pseudopaludicola mineira diferiu de Pseudopaludicola sp.1 pela morfologia dos pares 7, 8 e 11, posição da NOR no par 8 e pela distribuição de blocos heterocromáticos. As duas populações de P. saltica e a população de Pseudopaludicola aff. saltica apresentaram cromossomos com a mesma morfologia, exceto o par 8 que em P. saltica caracteriza cromossomos sexuais do tipo XX/XY, sendo o X telocêntrico e o Y submetacêntrico, ambos portadores da NOR, enquanto em Psedopaludicola aff. saltica o par 8 é telocêntrico, heteromórfico em tamanho, e apresenta marcação da NOR e banda heterocromática apenas no cromossomo maior do par. Os cariótipos de P. canga, Pseudopaludicola sp.2, Pseudopaludicola sp.3 e Pseudopaludicola aff. falcipes apresentaram cariótipos idênticos com 2n=18 cromossomos. Esses cariótipos diferem, no entanto, quanto à localização da NOR pericentromérica no braço curto do par 3 em P. canga e Pseudopaludicola sp.2 e telomérica no braço longo do par 9 em Pseudopaludicola sp.3 e Pseudopaludicola aff. falcipes. O padrão de bandamento C destas espécies mostrou-se bastante similar diferindo apenas pela presença de uma banda no braço longo do par 2 em P. canga e Pseudopaludicola sp.2 e ausente em Pseudopaludicola sp.3 e Pseudopaludicola aff. falcipes. Os dados citogenéticos permitiram diferenciar Pseudopaludicola sp.1 das demais espécies de 22 cromossomos já cariotipadas, sugerindo que possa se tratar de uma nova espécie. O sistema de determinação do sexo do tipo XX?/XY? detectado em P. saltica não foi relatado anteriormente para o gênero Pseudopaludicola, sendo esse o primeiro caso. A hipótese de fissão seguida de perda do braço menor em um dos homólogos de um par de cromossomos submetacêntricos é sugerida para explicar a origem do cromossomo X. O heteromorfismo do par 8 observado em Pseudopaludicola aff. saltica, pode ter ocorrido por mecanismo de crossing-over desigual. As espécies Pseudopaludicola canga e Pseudopaludicola sp.2 não puderam ser citogeneticamente diferenciadas, no entanto, não descartamos a possibilidade de serem táxons distintos. A grande similaridade dos cariótipos 2n=18 sugere que Pseudopaludicola sp.2, Pseudopaludicola sp.3 e Pseudopaludicola aff. falcipes possam também pertencer ao mesmo grupo em que se encontra P. canga, atualmente grupo "pusilla". Os dados sugerem ainda que Pseudopaludicola aff. falcipes (2n=18) seja proximamente relacionada à P. canga (2n=18) e não a P. falcipes (2n=22), apesar das semelhanças morfológicas entre seus exemplares. Os resultados obtidos no presente estudo reforçam a necessidade de uma extensa revisão taxonômica no gênero Pseudopaludicola. / Abstract: The genus Pseudopaludicola, of the family Leiuperidae, comprises 12 frog species and is widely distributed in South America. In Brazil, nine species have been described within this genus. As based on morphological data, the Pseudopaludicola species were classified in two groups named "pusilla" and "falcipes". Although this genus has undergone several taxonomic changes, recent molecular analyses revealed still unclear intergeneric relationships. The high morphological similarities among diverse species of Pseudopaludicola, associated to their sympatry in several localities, suggest taxonomic misidentification which had been based only in morphological characteristics. Besides, recent studies seem to indicate the existence of cryptic Pseudopaludicola species in several Brazilian localities. Cytogenetics of Pseudopaludicola has been scarce and restricted to the determination of chromosome number and morphology. Further cytogenetic analysis can contribute to differentiate the Pseudopaludicola species and, therefore, improve the sistematics of this genus. The objective of this work was to analyze the karyotypes of several Brazilian Pseudopaludicola species aiming at providing their characterization and further understanding of their systematic relationships. The analyzed species were the P. mineira, P. canga and P. saltica, from their type-localities (Serra do Cipó, MG; Serra dos Carajás, PA, and Chapada dos Guimarães, MT, respectively), P. saltica from Uberlândia, MG, Pseudopaludicola aff. saltica from Rio Claro (SP), Pseudopaludicola aff. falcipes from Icém (SP), and specimens of Pseudopaludicola sp. 1, 2 and 3, respectively from Andaraí (BA), Barreirinhas (MA) and Uberlândia (MG). Metaphases were obtained from intestinal epithelium and testicular cell suspensions, and stained with Giemsa or submitted to silver staining, in order to detect the nucleolus organizing regions (Ag-NOR), and to C-banding technique for heterochromatin localization. As based on chromosome number, there were two groups of karyotypes, with 2n=22 and 2n=18. The species P. mineira, Pseudopaludicola sp.1, P. saltica and Pseudopaludicola aff. saltica had a diploid number of 2n=22. Pseudopaludicola mineira and Pseudopaludicola sp.1 differed in the morphology of pairs 7, 8 and 11, in the NOR location in the pair 8 and in the heterochromatin distribution. The P. saltica and Pseudopaludicola aff. saltica populations showed very similar chromosomal morphology and identical heterochromatin pattern, except for the pair 8. In P. saltica, the pair 8 was characterized as sex chromosomes XX?/XY?, being the X classified as telocentric and Y submetacentric, whereas in Psedopaludicola aff. saltica, in both male and female specimens, the homologues of pair 8 are telocentrics, heteromorphic in size with the heterochromatin block present only in the longer homologue. The pair 8 is the NOR-bearing chromosome in both P. saltica and Psedopaludicola aff. saltica. High similarity was observed among the karyotypes of P. canga, Pseudopaludicola sp.2, Pseudopaludicola sp.3 and Pseudopaludicola aff. falcipes, all of them with 2n=18 chromosomes. However, these karyotypes differed in the NOR location, which was on pair 3 in P. canga and Pseudopaludicola sp.2, and on pair 9 in Pseudopaludicola sp.3 and Pseudopaludicola aff. falcipes. These species had similar heterochromatic blocks, except for one C-band on the long arm of pair 2 in P. canga and Pseudopaludicola sp.2, which was not observed in Pseudopaludicola sp.3 e Pseudopaludicola aff. falcipes). The cytogenetic data clearly distinguished Pseudopaludicola sp.1 from the other known species of this genus with 22 chromosomes, and suggested that this could be a not yet described species. The identification of sex chromosomes XX?/XY? in P. saltica, is the first case of sex chromosomes reported in the genus Pseudopaludicola. A mechanism of fission followed by loss of the short arm in one of homologues of a submetacentric pair could explain the origin of the X chromosome in P. saltica. The size heteromorphism in the homologues of the pair 8 of Pseudopaludicola aff. saltica, with the NOR site and heterochromatin present only in one of the homologues, could be explained by unequal crossing-over. The species Pseudopaludicola canga and Pseudopaludicola sp.2 could not be cytogenetically distinguished, suggesting that they belong to the same taxon. Since all the analyzed karyotypes of 2n=18 were very similar, we may suggest that Pseudopaludicola sp.2, Pseudopaludicola sp.3 e Pseudopaludicola aff. falcipes should be included in the same group of P. canga, which is currently allocated in the "pusilla" group. In addition, the results indicated that Pseudopaludicola aff. falcipes (2n=18) is more closely related to P. canga (2n=18) than to P. falcipes (2n=22), although the specimens are morphologically very similar and their identification is not unequivocal. Ultimately, the data presented herein reinforce the necessity of a taxonomic revision of the genus Pseudopaludicola. / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-08-22T15:45:41Z No. of bitstreams: 1 paulabotelhoferreira.pdf: 785454 bytes, checksum: 595027db7dae987c4e54324e928e8b46 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-08-28T13:24:40Z (GMT) No. of bitstreams: 1 paulabotelhoferreira.pdf: 785454 bytes, checksum: 595027db7dae987c4e54324e928e8b46 (MD5) / Made available in DSpace on 2018-08-28T13:24:40Z (GMT). No. of bitstreams: 1 paulabotelhoferreira.pdf: 785454 bytes, checksum: 595027db7dae987c4e54324e928e8b46 (MD5) Previous issue date: 2014-02-24 / Os moluscos pulmonados têm sido reconhecidos como modelos interessantes para o estudo de biodiversidade oculta em função de algumas características como a baixa vagilidade, capacidade de realizar auto-fecundação, além do histórico de identificações específicas baseadas somente nas conchas, caráter esse hoje sabidamente insuficiente para a distinção de espécies. A citogenética constitui uma abordagem que pode contribuir para a resolução taxonômica de grupos de moluscos terrestres, sendo, entretanto necessário o estabelecimento de protocolos experimentais. O objetivo do presente trabalho foi estabelecer protocolos para o estudo citogenético de moluscos terrestres, através da realização de bioensaios, visando testar diferentes tecidos, concentrações dos reagentes indicados e tempos de incubação. Para isso, foi realizada uma revisão prévia dos protocolos descritos para o filo Mollusca e delineados protocolos, posteriormente testados em bioensaios, utilizando-se a espécie Leptinaria unilamellata (Pulmonata, Subulinidae) como modelo experimental. O presente trabalho descreve o cariótipo da espécie L. unilamellata, com fórmula cariotípica 22m+6sm. Os resultados obtidos estão de acordo com os números cromossômicos descritos na literatura para espécies de moluscos terrestres da superfamília Achatinoidea, variando de 2n=44 a 2n=60 cromossomos. Além disso, com a técnica de coloração de nitrato de prata, observamos a presença de duas marcações no núcleolos correspondente às regiões organizadores de nucléolos, ou seja, regiões ativas do DNA. O estabelecimento de protocolos de citogenética adequados para o estudo de moluscos terrestres permitirá o aumento do número de espécies cariomorfologicamente estudadas, contribuindo para a melhor resolução da taxonomia e evolução desse grupo. / Pulmonate molluscs have been recognized as interesting models to study hidden biodiversity due to some biological characteristics as low vagility and self-fertilization capacity, besides the historic of species descriptions based solely on the shell. Cytogenetics is used to infer species relationships in several plant and animal taxa. This approach may contribute to the better resolution of the taxonomy within Pulmonata. The present study aimed to establish protocols to cytogenetic studies of terrestrial molluscs testing different target tissues, reagents concentrations and incubation times. We performed a review of the cytogenetic protocols described in the literature for phylum Mollusca and after that; we delineated protocols which were tested in bioassays, using the species Leptinaria unilamellata as experimental model. In the present study we found that L. unilamellata present diploid number of 56 chromosomes, 44 metacentrics e 12 submetacentrics. This result is in accordance with the chromosome numbers described to terrestrial snails from superfamily Achatinoidea, which varies from 2n=44 to 2n=60. Furthermore, with the technique of silver nitrate staining, we found the presence of two sites in the nucleus corresponding to nucleolus organizer regions, or active regions of DNA. The establishment of cytogenetic protocols adequate to terrestrial snails will allow increasing the number of land snail’ species karyomorphologically studied, contributing to the better resolution of the taxonomy and evolution of this group.

Orientadores: Eliana Regina Forni Martins, Ana Paula de Moraes / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T11:58:38Z (GMT). No. of bitstreams: 1 Polido_CarolinedoAmaral_D.pdf: 4429006 bytes, checksum: a6c32402c33fb0d67c72b757af07b400 (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital quando for liberada / Abstract: The abstract is available with the full electronic document when available / Doutorado / Biologia Vegetal / Doutora em Biologia Vegetal

Orientadores: Luciana Bolsoni Lourenço, Carmen Silvia Busin / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T12:08:20Z (GMT). No. of bitstreams: 1 Gatto_KalebPretto_M.pdf: 33988822 bytes, checksum: 7e3f3565dac9a540ea7c353f51068d4f (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural

Au cours de mon travail de doctorat, je me suis intéressé aux mécanismes qui contrôlent la séparation équitable du génome lors de la méiose dans l’ovocyte de souris.Le point de contrôle du fuseau contrôle la ségrégation des chromosomes en méiose : en cas d'attachement incorrect des chromosomes au fuseau, l'anaphase est retardée ce qui permet d'éviter les aneuploïdies. En métaphase, l’attachement des chromosomes homologues aux deux pôles opposés du fuseau, génère une force de tension au niveau des kinétochores. Mon travail de thèse a consisté à déterminer si la tension exercée sur les chromosomes est un signal qui permet de satisfaire le point du contrôle du fuseau en méiose I dans l'ovocyte de souris. Lorsque la tension exercée sur les chromosomes homologues par les microtubules est diminuée par un traitement pharmacologique, la dégradation de la sécurine, qui marque l’entrée en anaphase, est retardée. Si le point de contrôle du fuseau est inhibé en absence de tension, l’anaphase n’est pas retardée, ce qui indique que le point de contrôle du fuseau est sensible à la tension.Nous avons aussi montré que la kinase Aurora B/C n’est pas requise pour la réponse du point de contrôle du fuseau aux chromosomes non attachés, mais qu’elle est essentielle à la réponse du point de contrôle du fuseau à la baisse de tensionDans un contexte où les erreurs de ségrégation en méiose sont très fréquentes chez la femme et augmentent drastiquement avec l'âge, nos travaux pourraient permettre d'identifier si ces mécanismes de contrôle sont diminués et moins efficaces avec l'âge chez la femme. / At each cell division, chromosomes must be faithfully segregated so that exactly one set of chromosomes is passed on to the next generation. The spindle assembly checkpoint (SAC) ensures faithful chromosome segregation in meiosis: upon uncorrect attachment of the chromosome to the spindle, anaphase onset is delayed in order to avoid chromosome missegregation and aneuploidies. For my PhD thesis, I wanted to determine whether tension applied by the spindle microtubules on the chromosomes is itself a signal that satisfies the SAC in mouse oocyte meiosis I. When tension is decreased by small molecule inhibitors, securin degradation, which is a readout of anaphase onset, is delayed. If the SAC is inhibited, then tension defects cannot delay anaphase onset. This indicates that the SAC is able to delay anaphase onset upon tension defects.Furthermore, we showed that Aurora B/C kinase is not required for the SAC response to unattached chromosomes but that Aurora B/C is required for the SAC response to tension defects.Chromosome segregation errors are very common in women and increase with age. In that context, our work could help to identify whether these key control mechanisms are less efficient in the mammalian oocyte with age.

Philosophiae Doctor - PhD / With easy access to technology to generate expressed sequence tags (ESTs), several groups have sequenced from thousands to several thousands of ESTs. These ESTs benefit from consolidation and organization to deliver significant biological value. A number of EST projects are underway to extract maximum value from fragmented EST resources by constructing gene indices, where all transcripts are partitioned into index classes such that transcripts are put into the same index class if they represent the same gene. Therefore a gene index should ideally represent a non-redundant set of transcripts. Indeed, most gene indices aim to reconstruct the gene complement of a genome and their technological developments are directed at achieving this goal. The South African National Bioinformatics Institute (SANBI), on the other hand, embarked on the development of the sequence alignment and consensus knowledgebase (STACK) database that focused on the detection and visualisation of transcript variation in the context of developmental and pathological states, using all publicly available ESTs. Preliminary work on the STACK project employed an approach of partitioning the EST data into arbitrarily chosen tissue categories as a means of reducing the EST sequences to manageable sizes for subsequent processing. The tissue partitioning provided the template material for developing error-checking tools to analyse the information embedded in the error-laden EST sequences. However, tissue partitioning increases redundancy in the sequence data because one gene can be expressed in multiple tissues, with the result that multiple tissue partitioned transcripts will correspond to the same gene.Therefore, the sequence data represented by each tissue category had to be merged in order to obtain a comprehensive view of expressed transcript variation across all available tissues. The need to consolidate all EST information provided the impetus for developing a STACK human gene index, also referred to as a whole-body index. In this dissertation, I report on the development of a STACK human gene index represented by consensus transcripts where all constituent ESTs sample single or multiple tissues in order to provide the correct development and pathological context for investigating sequence variation. Furthermore, the availability of a human gene index is assessed as a diseasecandidate gene discovery resource. A feasible approach to construction of a whole-body index required the ability to process error-prone EST data in excess of one million sequences (1,198,607 ESTs as of December 1998). In the absence of new clustering algorithms, at that time, we successfully ported D2_CLUSTER, an EST clustering algorithm, to the high performance shared multiprocessor machine, Origin2000. Improvements to the parallelised version of D2_CLUSTER included: (i) ability to cluster sequences on as many as 126 processors. For example, 462000 ESTs were clustered in 31 hours on 126 R10000 MHz processors, Origin2000. (ii) enhanced memory management that allowed for clustering of mRNA sequences as long as 83000 base pairs. (iii) ability to have the input sequence data accessible to all processors, allowing rapid access to the sequences. (iv) a restart module that allowed a job to be restarted if it was interrupted. The successful enhancements to the parallelised version of D2_CLUSTER, as listed above, allowed for the processing of EST datasets in excess of 1 million sequences. An hierarchical approach was adopted where 1,198,607 million ESTs from GenBank release 110 (October 1998) were partitioned into "tissue bins" and each tissue bin was processed through a pipeline that included masking for contaminants, clustering, assembly, assembly analysis and consensus generation. A total of 478,707 consensus transcripts were generated for all the tissue categories and these sequences served as the input data for the generation of the wholebody index sequences. The clustering of all tissue-derived consensus transcripts was followed by the collapse of each consensus sequence to its individual ESTs prior to assembly and whole-body index consensus sequence generation. The hierarchical approach demonstrated a consolidation of the input EST data from 1,198607 ESTs to 69,158 multi-sequence clusters and 162,439 singletons (or individual ESTs). Chromosomal locations were added to 25,793 whole-body index sequences through assignment of genetic markers such as radiation hybrid markers and généthon markers. The whole-body index sequences were made available to the research community through a sequence-based search engine (http://ziggy.sanbi.ac.za/~alan/researchINDEX.html). / South Africa

An excess of males among the mentally retarded has been noted in practically all surveys of a mentally retarded population. It has been hypothesized that X-linked genes may account for this excess. The main purpose of this study was to test the hypothesis using data on the mentally retarded in British Columbia. A second purpose was to calculate the frequency of non-specific X-linked mental retardation in the population. In addition, an attempt was made to delineate clinical types of X-linked mental retardation. Data on the mentally retarded in British Columbia were obtained from the B.C. Health Surveillance Registry. The Registry also provided information on sibships with two or more sibs affected with non-specific mental retardation. Family histories on sibships with two or more affected males were obtained from the Department of Medical Genetics, institutions for the mentally retarded, namely Woodlands School and Tranquille, and in some cases personal interviews. The number of mothers in British Columbia giving birth to two or more sons in a defined birth cohort was retrieved from the linked family records of the B.C. Record Linkage Project. Families with a pattern of X-linked inheritance for non-specific mental retardation were ascertained while family histories on sibships with two or more affected males were being recorded and by reviewing files of other non-specific mentally retarded males in the Department of Medical Genetics, Woodlands School and Tranquille. Clinical and psychological characteristics of the mental retardation in males from these families were obtained from medical files from the same sources. Among the mentally retarded in British Columbia, there is an overall 28.2% excess of males. The extent of this excess is similar to that observed in other studies. This excess of males is seen at all levels of retardation except at the profound level. Mental retardation of known causes does not significantly contribute to the excess, which is due primarily to nonspecific mental retardation. Non-specific mental retardation in two or more sibs may be genetic in origin. Data from sibships with both males and females affected do not support an hypothesis of multifactorial inheritance with specific sex thresholds accounting for the excess of mentally retarded males. A ratio of 3.1:1 of sibships with two or more affected males to sibships with two or more affected females suggests that X-linked inheritance may account for the excess of male affected sibships. Family history data on sibships with two or more affected males provide evidence that X-linked genes can account for the excess of male affected sibships. A minimum frequency of 1.83 per 1,000 males for X-linked mental retardation in the population of British Columbia was calculated using sibship data. This frequency can account for the entire excess of non-specific mentally retarded males in the province. Mental retardation inherited in an X-linked pattern may be due to either single genes on the X chromosome or autosomal dominant genes with sex-limited expression. Distinguishing between the two types of genes was not possible in the present study. Specific clinical subtypes of X-linked mental retardation could not be differentiated due to a large amount of variability which was found not only in the level of retardation but also in associated psychological, neurological and physical characteristics. Although further clinical, biochemical and cytogenetic investigations of affected males in families with X-linked mental retardation may elucidate subtypes of non-specific mental retardation, variabiliy in phenotypic expression has been identified as an important feature of X-linked mental retardation. / Medicine, Faculty of / Medical Genetics, Department of / Graduate

Orientadores: Andrea Trevas Maciel Guerra, Roberto Benedito de Paiva e Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-04T01:13:43Z (GMT). No. of bitstreams: 1 Suzigan_LigiaZuppiConceicao_M.pdf: 719674 bytes, checksum: 0fd7aced48effd8567e687fc3397c183 (MD5) Previous issue date: 2004 / Resumo: Objetivo: Identificar a percepção das pacientes com Síndrome de Turner (ST) a respeito de sua condição. Casuística e Método: Entrevistas individuais com 36 pacientes com ST entre 15 e 25 anos e mais de 2 anos de acompanhamento, abordando temas referentes ao impacto no momento do diagnóstico, compreensão a respeito da ST, seu impacto sobre a vida atual e expectativas de futuro. Resultados: Apenas 1/3 compreendeu o diagnóstico de ST imediatamente, e o sentimento associado a esse momento foi freqüentemente neutro (17) ou de preocupação (12). Cerca de 1/3 não soube explicar a etiologia da ST, não relacionou a ela os sintomas que apresenta e(ou) acredita haver cura. Em sua vida atual, embora a grande maioria declare que a ST não interfere em sua vida (2/3) e se considere feliz (3/4), em mais da metade dos casos há evidências de dificuldades de interação social e de relacionamento amoroso, baixa auto-estima, insatisfação com a aparência física, em particular a baixa estatura e sofrimento com a questão da esterilidade. Suas expectativas de futuro estão predominantemente ligadas a trabalho e estudo; mesmo estando com 19 anos, em média, uma em cada duas ainda espera crescer. Conclusão: Além da abordagem médica da ST, é fundamental que o conhecimento das pacientes a respeito dessa síndrome e as questões referentes a esterilidade, baixa estatura, auto-imagem e interações sociais sejam alvo de atenção especial e contínua a partir do momento do diagnóstico; a situação ideal seria a de atuação de um psicólogo juntamente com a equipe médica / Abstract: Objective: To identify the perception of patients with Turner syndrome (TS) about their condition. Methodology: Thirty-six women with TS, aged between 15 and 25 years and with over two years of medical follow-up, were individually interviewed about: the impact of TS at the moment of the diagnosis, their understanding of the syndrome, its effect in their current lives and their expectations for the future. Results: Only one third of the patients understood the diagnosis immediately and their feelings associated to that moment were neutral (17) or concerned (12). About one third of the interviewed women were unable to explain the etiology of TS, they have not related their symptoms with TS and/or believe there might be a cure for it. Although most say that the syndrome has no interference in their current lives (2/3) and that they consider themselves happy persons (3/4), in more than half of the interviews there are evidences of difficulties with social interactions and love relationships, low self-esteem, dissatisfaction with their physical appearances, mainly short stature, and worries about infertility. Their hopes for the future refer mainly to study and have a job; growing up expectation was mentioned by one in two of the women, in spite of their mean age of 19 years. Conclusion: Besides medical treatment, it is important that the knowledge of the patients about the syndrome and some issues as infertility, short stature, self-image and social interactions receive proper and continuous attention from the moment of the diagnosis. The ideal situation should be a joint-action of the psychologist and the medical team / Mestrado / Saude da Criança e do Adolescente / Mestre em Saude da Criança e do Adolescente

The X chromosome is present as a single copy in the heterogametic sex, and this hemizygosity is expected to drive unusual patterns of evolution on the X relative to the autosomes. For example, the hemizgosity of the X may lead to a lower chromosomal effective population size compared to the autosomes, suggesting that the X might be more strongly affected by genetic drift. However, the X may also experience stronger positive selection than the autosomes, because recessive beneficial mutations will be more visible to selection on the X where they will spend less time being masked by the dominant, less beneficial allele—a proposal known as the faster-X hypothesis. Thus, empirical studies demonstrating increased genetic divergence on the X chromosome could be indicative of either adaptive or non-adaptive evolution. We measured gene expression in Drosophila species and in D. melanogaster inbred strains for both embryos and adults. In the embryos we found that expression divergence is on average more than 20% higher for genes on the X chromosome relative to the autosomes; but in contrast, in the inbred strains, gene expression variation is significantly lower on the X chromosome. Furthermore, expression divergence of genes on Muller's D element is significantly greater along the branch leading to the obscura sub-group, in which this element segregates as a neo-X chromosome. In the adults, divergence is greatest on the X chromosome for males, but not for females, yet in both sexes inbred strains harbour the lowest level of gene expression variation on the X chromosome. We consider different explanations for our results and conclude that they are most consistent within the framework of the faster-X hypothesis.

(English) Sex determination plays an important role in the viability of populations and species evolvability. This is one of the reasons why sex determination has become an important subject of many studies during more than the last 100 years. The thesis focuses on the evolution of sex determination systems in toxicoferan reptiles. Toxicofera is a group of squamate reptiles containing more than 6000 species. Their species richness is also reflected in the diversity of their sex determination systems. The presence of environmental sex determination (ESD) as well as genotypic sex determination (GSD) with either XX/XZ or ZZ/ZW sex chromosomes, was reported among the toxicoferan species; however, the current knowledge on sex determination in toxicoferan reptiles is not equally distributed across their lineages. The main aim of the theses is to expand our knowledge on sex chromosome evolution using cytogenetic methods in snakes, chameleons and anguimorphan lizards. The first part of the thesis deals with the sex chromosome evolution in caenophidian and henophidian snakes. It is focused mainly on the variability in the distribution of repetitive content as well as heterochromatinization of the W chromosome of caenophidian snakes. While the sex chromosomes of Caenophidia are cytogenetically quite well...