Chan Ming Lok. / Thesis submitted in: December 1999. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 93-108). / Abstracts in English and Chinese. / Ackowledgments --- p.i / Abstract in English --- p.ii / Abstract in Chinese --- p.iii / List of Abbreviations --- p.iv / List of Tables --- p.v / List of Figures --- p.vi / Chapter Chapter 1 --- Introduction and Objectives / Chapter 1.1 --- Hepatocellular Carcinoma --- p.1 / Chapter 1.1.1 --- Epidemiology --- p.1 / Chapter 1.1.2 --- Geographical Distribution --- p.1 / Chapter 1.1.3 --- Sex and Age --- p.1 / Chapter 1.1.4 --- Etiology --- p.2 / Chapter 1.1.5 --- Molecular Basis of HCC --- p.3 / Chapter 1.1.6 --- Situation in China and Hong Kong --- p.4 / Chapter 1.2 --- The Hepatitis B Virus --- p.5 / Chapter 1.2.1 --- Morphology --- p.5 / Chapter 1.2.2 --- Structure of the HBV Genome --- p.6 / Chapter 1.2.3 --- Functional Domains of the HBV Genome --- p.9 / Chapter 1.2.4 --- Pathogenesis of HBV Infection --- p.11 / Chapter 1.3 --- HBx --- p.12 / Chapter 1.3.1 --- The HBV x Gene --- p.12 / Chapter 1.3.2 --- The HBX Protein --- p.13 / Chapter 1.3.3 --- "Preferential HBX Expression in Sera, Hepatitis, Cirrhosis and HCC" --- p.13 / Chapter 1.3.4 --- Cellular Localization of HBX --- p.14 / Chapter 1.3.5 --- Animal Studies --- p.15 / Chapter 1.3.6 --- Functional Studies on HBX --- p.15 / Chapter 1.3.7 --- Variations in the HBx Gene --- p.21 / Chapter 1.4 --- Objectives of this Study --- p.24 / Chapter Chapter 2 --- Methods and Materials Methods / Chapter 2.1 --- Paraffin Embedding of Patient Tissue Samples --- p.26 / Chapter 2.1.1 --- Tissue Processing --- p.26 / Chapter 2.1.2 --- Paraffin Embedding of Tissue Samples --- p.26 / Chapter 2.2 --- Sectioning of Paraffin Embedded Tissue Sections --- p.26 / Chapter 2.3 --- Immunohistochemical Staining of Paraffin Embedded Tissue Sections --- p.26 / Chapter 2.3.1 --- Dewaxing of Paraffin-Embedded Tissue Sections --- p.26 / Chapter 2.3.2 --- Rehydration of Tissue Sections --- p.27 / Chapter 2.3.3 --- Antigen Retrieval --- p.27 / Chapter 2.3.4 --- Quenching of Endogenous Hydrogen Peroxidase --- p.27 / Chapter 2.3.5 --- Blocking of Endogenous Biotin and Non-Specific Protein Binding --- p.27 / Chapter 2.3.6 --- Antibody Incubation and Color Development --- p.27 / Chapter 2.3.7 --- Counterstaining and Coverslip Mounting --- p.28 / Chapter 2.3.8 --- Interpretation of Immunostaining Results --- p.28 / Chapter 2.4 --- DNA Extraction from HCC Tissues --- p.28 / Chapter 2.4.1 --- Sectioning of Frozen HCC Specimens --- p.28 / Chapter 2.4.2 --- Proteinase K Digestion and Phenol Chloroform Extraction --- p.29 / Chapter 2.4.3 --- Ethanol Precipitation and Re-suspension in Tris-EDTA (TE) Buffer --- p.29 / Chapter 2.5 --- Quantitation and Purity Check of Extracted DNA --- p.29 / Chapter 2.6 --- Quality Check for Extracted Genomic DNA --- p.30 / Chapter 2.6.1 --- Agarose Gel Electrophoresis --- p.30 / Chapter 2.6.2 --- Polymerase Chain Reaction (PCR) of the β-globin Gene --- p.30 / Chapter 2.6.3 --- Analysis of PCR Fragments by Agarose Gel Electrophoresis --- p.30 / Chapter 2.7 --- Polymerase Chain Reaction Amplification of HBs and HBx Genes of the Hepatitis B Virus --- p.31 / Chapter 2.8 --- Southern Blot of HBx PCR Fragments --- p.31 / Chapter 2.8.1 --- Immobilization of DNA onto a Positively Charged Nylon Membrane and Pre-hybridization --- p.31 / Chapter 2.8.2 --- Radio-labeling of an HBV Probe --- p.32 / Chapter 2.8.3 --- Hybridization of a 32P-labeled HBV Probe and Film Exposure --- p.32 / Chapter 2.9 --- Cloning of PCR Fragments into pGEM®-T Vector for Sequencing --- p.33 / Chapter 2.9.1 --- Gel Extraction and Purification --- p.33 / Chapter 2.9.2 --- Ligation --- p.33 / Chapter 2.10 --- Transformation of Competent DH5a cells --- p.34 / Chapter 2.10.1 --- Preparation of Competent DH5α Using Calcium Chloride --- p.34 / Chapter 2.10.2 --- Heat Shock of Competent DH5α Cells --- p.34 / Chapter 2.10.3 --- Plating of Transformed Cells onto LB Agar Plates --- p.34 / Chapter 2.10.4 --- Screening of Transformants for Inserts --- p.35 / Chapter 2.11 --- Miniprep of Plasmid DNA --- p.35 / Chapter 2.11.1 --- Inoculation of Bacterial Clones --- p.35 / Chapter 2.11.2 --- DNA Extraction by Alkaline Lysis and Phenol/Chloroform --- p.35 / Chapter 2.11.3 --- Ethanol Precipitation and Re-suspension in TE Buffer --- p.35 / Chapter 2.11.4 --- Confirmation of Positive Clones --- p.36 / Chapter 2.12 --- Sequencing of pGEM®-T Cloned HBx PCR Fragments --- p.36 / Chapter 2.13 --- Construction of the HBx-GFP Plasmid --- p.36 / Chapter 2.13.1 --- PCR Amplification of HBx Gene Inserts --- p.36 / Chapter 2.13.2 --- Confirmation of HBx Insert Sequence by DNA Sequencing --- p.37 / Chapter 2.13.3 --- Restriction Digest of HBx-pGEM®-T Plasmids to Obtain HBx Inserts --- p.37 / Chapter 2.13.4 --- Restriction Digest of pEGFP-Nl Cloning Vector for Cloning --- p.37 / Chapter 2.13.5 --- Ligation of HBx Inserts into the pEGFP Cloning Vector --- p.37 / Chapter 2.14 --- Large Scale Plasmid DNA Preparation --- p.38 / Chapter 2.15 --- Cell Culture --- p.39 / Chapter 2.16 --- Transfection using LipofectAminéёØ --- p.39 / Chapter 2.16.1 --- Seeding of Cells for Coverslip Growth --- p.39 / Chapter 2.16.2 --- Transfection using LipofecAminéёØ --- p.39 / Chapter 2.17 --- Cell Fixation and DAPI Staining Materials --- p.40 / Chapter 2.18 --- Chemicals --- p.41 / Chapter 2.19 --- Antibodies --- p.41 / Chapter 2.20 --- "Formalin-fixed, Paraffin Embedded Tissues of HCC Tissues from Xiamen" --- p.41 / Chapter 2.21 --- Frozen Liver Tissues --- p.41 / Chapter 2.22 --- PCR Reagents --- p.43 / Chapter 2.23 --- Primers --- p.43 / Chapter 2.24 --- Plasmid --- p.43 / Chapter 2.25 --- Enzymes --- p.43 / Chapter 2.26 --- Ligation Reagents --- p.43 / Chapter 2.27 --- Cloning Vectors --- p.45 / Chapter 2.28 --- Competent Cell --- p.45 / Chapter 2.29 --- Hela and HepG2 Cell Line --- p.45 / Chapter Chapter 3 --- Results / Chapter 3.1 --- Hepatitis B Virus Status of HCC Patients from Hong Kong and Xiamen --- p.46 / Chapter 3.2 --- Immunohistochemical Studies of the HBx Protein in Hong Kong and Xiamen HCC --- p.46 / Chapter 3.2.1 --- Cross Reaction of Anti-99 with Cytokeratin 18 (CK18) --- p.46 / Chapter 3.2.2 --- HBx Expression in HCC Patient Tissue Samples from Hong Kong --- p.50 / Chapter 3.2.3 --- HBxAg Staining in HCC Tissue Samples from Xiamen --- p.50 / Chapter 3.3 --- Agarose Gel Electrophoresis of DNA Extracted from Frozen Liver Tissues --- p.50 / Chapter 3.4 --- PCR Amplification of the β-globin Gene --- p.55 / Chapter 3.5 --- PCR Amplification of the HBs Gene from Liver Samples of HCC Patients from Hong Kong --- p.55 / Chapter 3.6 --- PCR Amplification of the HBx Gene from Liver Samples of HCC Patients from Hong Kong --- p.55 / Chapter 3.7 --- Amplification of the HBx Gene from Serum Samples of Chronic Hepatitis B Virus from Hong Kong Using Nested PCR --- p.61 / Chapter 3.8 --- Southern Blot of HBx PCR Fragments --- p.61 / Chapter 3.9 --- Cloning and Sequencing of the HBx Gene in HCC and Chronic Hepatitis B Patient Samples from Hong Kong --- p.61 / Chapter 3.10 --- Expression Pattern of Wild-type HBx-GFP Fusion Protein in Transiently Transfected HeLa and HepG2 Cells --- p.73 / Chapter 3.11 --- Expression Patterns of HBx-GFP with and without Mutations at Codons 130 and 131 in HeLa and HepG2 Cell Line --- p.78 / Chapter 3.12 --- Growth Kinetics of HeLa Cells Transfected with GFP and Wild-type HBx-GFP with and without Mutations in Codons 130 and131 --- p.81 / Chapter Chapter 4 --- Discussion / Chapter 4.1 --- HBxAg Expression in Tumorous and Surrounding Non-tumorous Tissues --- p.83 / Chapter 4.2 --- "Detection of the HBx Gene in Sera, Non-tumorous and Tumorous Tissues" --- p.84 / Chapter 4.3 --- HBx Gene Mutations in Chronic Hepatitis and HCC --- p.85 / Chapter 4.3.1 --- Codon 127 (HBV nt 1752-1754) --- p.85 / Chapter 4.3.2 --- Codons 130 and 131 (HBV nt 1761-1766) --- p.86 / Chapter 4.3.3 --- Lack of Correlation between HBx Gene Mutations and Lack of HBxAg Expression --- p.87 / Chapter 4.4 --- Cellular Localization of HBxAg in Transiently Transfected Cells Lines --- p.88 / Chapter 4.5 --- Functional Difference Between Wild-type and Mutant HBX Protein --- p.89 / Chapter Chapter 5 --- Conclusions and Directions for Further Studies / Chapter 5.1 --- Conclusions --- p.91 / Chapter 5.2 --- Directions for Further Studies --- p.92 / References --- p.93 / Appendix / Chapter A1 --- Recipes of Reagents Used in this Study --- p.109 / Chapter A2 --- Schematic Setup of Downward Capillary Transfer of DNA --- p.112 / Chapter A3 --- Circle Map of the pGEM®-T Cloning Vector and Construct of the HBx-pGEM®-T Plasmid --- p.113 / Chapter A4 --- Circle Map of the pEGFP-Nl Cloning Vector and Construct of the HBx-GFP Plasmid --- p.114

Meta-analysis is a statistical technique that combines results from multiple independent studies to make inferences about parameters of interest. Although it is popular for parameter estimation and hypothesis testing, meta-analytic approaches that incorporate heterogeneous studies have not been fully developed. For heterogeneous studies, we do not expect all of the studies to have the same true underlying effect and the use of the fixed-effects model in a meta-analysis in this situation violates the assumption of homogeneity of effect size. Heterogeneity among studies can arise from multiple sources such as differences in populations by ancestry, differences in study designs, and different impacts of environmental exposures on the effect of the variable of interest. In this thesis, we introduce an analytic strategy and statistical models for meta-analysis of potentially heterogeneous studies. First, we propose a two-stage clustering approach to account for heterogeneity in trans-ethnic meta-analysis of genome-wide association studies (GWAS). Specifically, we cluster studies in the two-stage approach using cohort-specific genetic information prior to meta-analysis to account for between-cluster heterogeneity as well as to bolster within-cluster homogeneity. An extensive simulation study shows that this approach improves power and diminishes computational intensity compared to existing methods for trans-ethnic meta-analysis. Next, under a meta-regression framework, we develop a likelihood ratio test (LRT) statistic to accommodate multiple random effects. We allow multiple sources of heterogeneity in terms of study characteristics and model the heterogeneities as random effects. We show that the proposed LRT maintains a similar or higher power than other existing methods in a simulation study especially when heterogeneity exists. We apply this new approach to meta-analyze genome-wide association data. Lastly, we derive a score test in the same context as our proposed new LRT and show the substantial advantage of the score test in computational efficiency compared to the new LRT. The introduced strategy and methodologies can effectively and efficiently aggregate the evidence from potentially heterogeneous studies in statistical genetics and other research areas.

Introduction: Magnesium is required by the human body in modest amounts for the maintenance of health and optimal functioning. Objectives: This portfolio of work sets out to investigate whether magnesium supplementation has hypotensive effects and to determine if habitual dietary magnesium intake or loading strategies modulate the effects of magnesium supplementation. The habitual dietary magnesium intake of hypertensive patients was also examined to ascertain adequacy of dietary magnesium in this cohort. A meta-analysis was performed on the effect of magnesium supplementation on blood pressure. Other variables such as dosage, duration and study design were considered and findings from the meta-analysis used to influence future work. A further objective was to examine the effect of supplementation on aerobic and resistance exercise and subsequent recovery. Finally, the efficacy of an alternative means of magnesium delivery in the form of a transdermal magnesium cream was investigated. Methods: A 300 mg.day-1 elemental magnesium aspartate or magnesium citrate was used as a supplementation in studies 1,2,4 and 5. Participants were instructed to continue with their normal diet and for study 6 participants were required to eat the same foods for the 24 hours prior to both laboratory blood taking sessions. With the exception of the meta-analysis, food diaries were kept for various lengths of time, detailed in the publications. Aerobic and resistance exercise protocols were carried out in studies 1,2 and 4, with both performance and cardiovascular parameters investigated for any effect from supplementation. Where supplementation was in the form of a transdermal cream, this was applied to the torso and absorption of the cream was determined by investigating changes in serum and urinary magnesium levels. Summary of results: Blood pressure decreased with magnesium supplementation of 300 mg.day-1 for 7 days with greater reductions in systolic versus diastolic blood pressure consistently evident. Magnesium supplementation of 300 mg.day-1 for 7 and 14 days increased power during resistance exercise but no changes in aerobic exercise performance were observed. A high habitual dietary magnesium intake attenuated the hypotensive effect derived from magnesium supplementation when compared to those on a low habitual dietary intake. The meta-analysis supported these results. A habitually low dietary magnesium intake was observed in a cohort of clinically diagnosed primary hypertensives. Conclusion: These studies show that there is a link between low habitual dietary magnesium intake and elevated blood pressure and that magnesium supplementation appears to be associated with blood pressure. An improvement in resistance exercise performance with magnesium supplementation was also observed. Finally, a transdermal magnesium cream was shown to increase serum magnesium levels and may provide an alternative to oral supplementation.

Sialic acids are involved in many biological processes. In glycoproteins and glycolipids they are essential for signalling and mediate molecular interactions as well as being targets for many pathogens such as influenza virus. The synthesis of sialylated glycoconjugates is of great importance. The incorporation of sialic acid through chemical synthesis carries several difficulties, enzymatic strategies using glycosyltransferases are very attractive alternative strategy, and have been used on a broad range of substrates forming glycosidic linkages with regio-and stereo-specificity. The work presented herein shows the study and application of two enzymes, Photobacteriumdamselae alpha2,6-sialyltransferase (Pd2,6ST) and Trypanosoma cruzi trans-sialidase (TcTS) which are used in the synthesis of sialyloligosaccharides. Both enzymes were expressed in E.coli and purified for biotransformations. In the first application new sialylated chromogenic compounds were generated through this enzymatically by using TcTS and a Pd2,6ST. These compounds were used for the detection of neuraminidase activity in a number of biological samples and led to the discovery of neuraminidase activity from Bacillus pumilus and Arthrobacter aurescens, two different bacteria in which the presence of neuraminidases had never been described. Secondly, TcTS was used to study lipid glycosylations. Glycans in biological systems can be associated to complex lipidic microdomains and the presence of these microdomains can affect the activity of some enzymes. In case of Trypanosoma cruzi trans-sialidase, a decreased activity was detected when the acceptor substrate was part of the aggregated lipid rafts compared to activity observed when the reaction was performed using fully dispersed substrate. Thirdly, the sialylation of glycoarrays using Pd2,6ST was studied. For the first time, sialylated glycans with alpha2,6- glycosidic linkages were successfully incorporated into a gold glycoarray platform, which had been previously developed for the label-free detection of carbohydrate-protein interactions. Successful enzymatic incorporation of sialic acids onto the arrays was confirmed with commercial available lectins. Finally, by using the gold glycoarray platform containing both 2,3 and 2,6 linked sialic acids as well as other common glycans, the carbohydrate-binding properties of the surface proteins of the bacterium Lactobacillus reuteri was studied using MALDI-ToF MS techniques. For first time, strong interactions were observed between a mucus binding protein and Neu5Ac alpha2,6-linked glycans, with much weaker binding to 2,3-linked analogues. Such glycan structures have been identified in abundant manner in colon mucins and this study contributes to the understanding of complex interactions between mucins and probiotic organisms as well as pathogenic bacteria. These studies show that glycan arrays can contribute both to the understanding of probiotics as well as to the identification of glycan binding proteins as targets for new drugs.

Made available in DSpace on 2014-06-11T19:31:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-05-26Bitstream added on 2014-06-13T19:19:51Z : No. of bitstreams: 1 silva_mta_dr_araiq.pdf: 3269290 bytes, checksum: 226805a8de91ee25f88e83234f61efa0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A família Trypanosomatidae inclui diversos parasitas protozoários responsáveis por diferentes doenças humanas. Várias evidências sugerem importantes diferenças entre a maquinária de tradução e processamento de mRNA (trans-splicing) em Tripanosomatídeos quando comparados com eucariótos superiores. Neste contexto, alguns fatores importantes para o funcionamento da célula eucarióticas são os pequenos complexos constituídos de proteínas e RNA, chamados de ribonucleoproteínas (U snRNPs). Esta partículas possuem papel essencial no processamento de RNA mensageiros e durante a reação de splicing apresenta um core comum composto por proteínas (proteínas Sm) and RNAs estruturais (U snRNAs) e um conjunto de proteínas específicas de cada complexo. Embora bem definidas em mamíferos, snRNPs permanecem pouco caracterizadas em Tripanosomatídeos. Ferramentos de bioinformática identificaram quatro possíveis proteínas específicas do complexo U5 snRNP (U5-15K, U5-40K, U5-102K e U5-116K), e importantes parâmetros foram determinados, como peso molecular estimado, domínios e motivos conservados. Este trabalho demonstrou que U5-15K e 45-102K são altamente conservadas entre o Tripanosomatídeos e os domínios Dim1 and Prp1 foram identificados, respectivamente. Técnicas de purificação de complexos (PTP-tag) revelaram que estas proteínas interagem com o U5 snRNA, sugerindo que participem do complexo U5 snRNP. Análises funcionais demonstraram que U5-15K é essencial para viabilidade celular e que de alguma forma esta asssociada tanta a reação de cis quanto de tras-splcing. Experimentos de imunolocalização de U5-15K and U5-102K corroboram este dados, uma vez que as protínas em questão possuem localização nuclear. / There are several protozoan parasites in Trypanosomatidae family, including different agents responsible for human diseases. Several evidences suggest important differences in the translational system and mRNA processing (trans-splicing) in Trypanosomatids when compared to higher eukaryotes. In this context, some important factors for the functioning of eukaryotic cells are the small complexes of RNA and proteins; these particles of ribonucleoproteins (UsnRNPs) have an essential role in the pre-mRNA processing, mainly during splicing. UsnRNP presents a common protein core associated between itself and with the snRNA, named Sm proteins and specific proteins of each snRNP. Even though they are well defined in mammals, snRNPs are still not well characterized in certain Trypanosomatids. Bioinformatics analysis identified four possible U5 snRNP specific proteins (U5-15K, U5-40K, U5-102K and U5-116K), and important parameters were determinated, as estimated molecular weight, motifs and conserved domains. This work shows that the U5-15K and U5-102K proteins are highly conserved among different Tryponosomatids species and Dim1 and Prp1 domains were identified, respectively. Tandem affinity pull-down assay revealed that these proteins interact with U5snRNA, suggesting its participation in U5snRNP particle, and functional analysis showed that U5-15K is essential for cell viability and it is associated in some way to trans and cis-splicing machinery. Immunolocalization experiments corroborated those data, showed U5-15K and U5-102K in the nucleus of the cell.

Submitted by PPG Letras (letraspg@pucrs.br) on 2018-10-05T18:36:50Z No. of bitstreams: 1 Disserta??o Virg?nea Novack Santos Da Rocha.pdf: 1003268 bytes, checksum: 7e32abb92d4b5d25d94162e18905f488 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-10-08T13:11:51Z (GMT) No. of bitstreams: 1 Disserta??o Virg?nea Novack Santos Da Rocha.pdf: 1003268 bytes, checksum: 7e32abb92d4b5d25d94162e18905f488 (MD5) / Made available in DSpace on 2018-10-08T13:23:49Z (GMT). No. of bitstreams: 1 Disserta??o Virg?nea Novack Santos Da Rocha.pdf: 1003268 bytes, checksum: 7e32abb92d4b5d25d94162e18905f488 (MD5) Previous issue date: 2018-01-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Based on the contemporary reflections on gender, especially on transsexuality, the purpose of this reflection is to try to establish some relations between these themes and contemporary Brazilian literature. For this, it is performed a critical and a comparative analysis of the narratives. Do fundo do po?o se v? a lua, by Joca Reiners Terron (2010); S?rgio Y vai ? Am?rica, by Alexandre Vidal Porto (2014), and Carlos Henrique Schroeder's As fantasias eletivas (2016), since they all feature a trans * character (respectively Cleo, Sandra and Copi). Thus, it is observed that all narratives presents the same logic of life organization, that is, a cycle of life directly related to the gender identity of the characters. Namely: a family structure that silences and/or excludes the child, a need for geographical displacement and premature death. In this sense, in order to engage in such reflection, we start with Butler's (2016) concept of performativity and Preciado?s (2014) concept of plasticity of the genre, in order to understand the mechanisms of discursive reiteration of the genre as well as the possibility of counterproduction by half of the break with the limits on the "truth" of bodies. In addition, important contributions are also those of Jesus (2013 and 2014a) and Vergueiro (2016), situating the gender issues in the context of transfeminism, the researchers theorize about the power structure that subjects the trans* identity in our society: the cisnormativity. Thus, it was possible to conclude that in the three narratives there are allusions to the identities of the characters as falsehood, artificiality and copy. Cleo is a trans* woman who tries to build herself up as a usurpation of female stereotypical identities by the cinema; Sandra is a self-conscious woman besides having an excellent financial condition, but ends up having the same fate as the other characters, which, however, is treated under the sign of chance. Finally, Copi is a great representative of the reality of many Brazilian transvestites, since she is relegated to abandonment and solitude. However, their identities are also tied to acting, lies and falsehood. / A partir das reflex?es contempor?neas sobre g?nero, em especial, sobre a transexualidade, o objetivo dessa reflex?o foi o de tentar estabelecer algumas rela??es entre estas tem?ticas e a literatura brasileira contempor?nea. Para isso, efetuou-se uma an?lise cr?tica e comparatista das narrativas Do fundo do po?o se v? a lua, Joca Reiners Terron (2010); S?rgio Y vai ? Am?rica, Alexandre Vidal Porto (2014) e As fantasias eletivas, de Carlos Henrique Schroeder (2016), uma vez que todas elas apresenta uma personagem trans* (respectivamente Cleo, Sandra e Copi). Assim, observou-se que todas as narrativas apresentam uma mesma l?gica de organiza??o da vida, isto ?, um ciclo da vida diretamente relacionados a identidade de g?nero das personagens. A saber: uma estrutura familiar que silencia e/ou exclui a crian?a, uma necessidade de deslocamento geogr?fico e a morte prematura. Nesse sentido, para empenhar tal reflex?o, partimos dos conceitos de performatividade de Butler (2016) e plasticidade do g?nero Preciado (2014) para compreender os mecanismos de reitera??o discursivas do g?nero bem como a possibilidade de contraproduzi-los por meio do rompimento com os limites sobre a ?verdade? dos corpos. Al?m disso, importantes contribui??es foram tamb?m as de Jesus (2013 e 2014a) e Vergueirro (2016), ao situar as quest?es de g?nero no ?mbito do transfemino, as pesquisadoras teorizam sobre a estrutura de poder que sujeita as identidade trans* em nossa sociedade: a cisnormatividade. Dessa forma, foi poss?vel concluir nas tr?s narrativas existem alus?es as identidades das personagens enquanto falsidade, artificialidade e c?pia. Cleo ? uma mulher trans* que busca construir enquanto usurpa??o de identidades femininas estereotipas pelo cinema; Sandra ? uma mulher trans* consciente de si al?m de ter uma excelente condi??o financeira, mas que acaba tendo o mesmo destino das outras personagens, o que, por?m, ? tratado sob o signo do casualidade. Por fim, Copi ? uma grande representante da realidade de muitas travestis brasileiras, uma vez que ? relegada ao abandono e a solid?o. No entanto, sua identidade tamb?m ? atrelada a atua??o, mentira e falsidade

The purpose of this research was to gain a better understanding of transgender people and allow participants to have a voice in describing the experience of those in the transgender community. This study was conducted utilizing qualitative analysis through individual interviews with six participants. One of the major key findings of this study was the prevalence of depression among all participants. Another key finding of this study found safety among peers to be an issue for those transitioning from male to female. From the findings, it is imperative for social work practitioners to understand this marginalized community and be sensitive to the issues they face, such as: higher rates of mortality, suicide, substance abuse, and mental health issues.

The Break is a personal investigation into problems and possibilities of representing my specific transgender identity. Trans as a tactic to speak about a state of forever becoming, forever in between, outside of and in opposition to dominant social norms of being. Trans as a model for a different way of viewing and being in the world. Can we form a different kind of horizontal shared power though a collective refusal to play into existing structures from which we have been excluded? What are the potentials for modeling other ways of being, other ways of (dis)engaging, other ways to be in the world? What if we can disengage words from their established meanings? Can we re-see each other without the language that upholds the social conditions that maintain internalized categories? Can we collectively create the conditions to imagine the possibility of building other worlds in this world?

Lobjectif de notre travail était triple. Dune part, nous voulions caractériser lévolution de la trace mnésique dans les 48 heures qui suivent lapprentissage explicite dune tâche motrice séquentielle (FTT). Nous nous sommes intéressés plus particulièrement à la période qui suit immédiatement lapprentissage de cette tâche. En effet, cette période, particulièrement vulnérable à une interférence au sens large du terme, semble cruciale dans le processus de consolidation de la trace mnésique. Dautre part, les différentes étapes de lapprentissage moteur ayant été définies, nous voulions étudier le rôle spécifique de M1 au cours de chacune de celles-ci. Pour ce faire, nous avons utilisé la SMTr à faible fréquence que nous avons appliquée à différents délais sur le scalp en regard du cortex moteur primaire controlatéral à la main utilisée pour la tâche. Enfin, quelques études récentes suggérant que la SMTr à haute fréquence pourrait améliorer certaines tâches cognitives et motrices chez le sujet sain comme chez le sujet cérébrolésé, nous avons tenté daugmenter la performance de nos volontaires sains en leur appliquant la SMTr à haute fréquence en regard du cortex moteur primaire directement après lapprentissage de la tâche. Au terme de ce travail nos conclusions sont les suivantes : 1. Le traitement de la trace mnésique fraîche est un processus dynamique qui passe au moins par trois étapes. a. Lors de la première étape, caractérisée par les 30 premières minutes qui suivent lentraînement, la trace mnésique est accessible, plus efficace quà la fin de lentraînement mais fragile aux perturbations extérieures. Une interférence survenant à ce moment peut détériorer le rappel immédiat de la tâche et dans certaines conditions la performance à long terme. b. La seconde étape, caractérisée par les heures qui suivent lentraînement et pendant lesquelles le sujet est éveillé, correspond à une phase de stabilisation de la trace mnésique durant laquelle celle-ci est moins accessible mais plus robuste aux interférences. c. La troisième étape correspond à lamélioration de performance survenant après au moins une nuit de sommeil. Bien que nous nayons pas testé spécifiquement le rôle du sommeil, nous avons montré que 24 et 48 heures après lentraînement, la trace mnésique est optimale et de nouveau accessible lors de lexécution de la tâche. 2. La première étape nest pas dépendante du niveau de performance du sujet. Elle est présente après un premier entraînement mais également 48 heures plus tard après un second entraînement. Il reste néanmoins à préciser si ce gain de performance survenant précocement après lentraînement est toujours présent ou non après plusieurs semaines dentraînement, lorsque le sujet a atteint son niveau de performance maximal. 3. Le rôle de la première étape dans le processus de consolidation à long terme reste à préciser. Dun côté, le gain de performance acquis lors de la première étape (5 et 30 minutes) est proportionnel au gain de performance acquis lors de la troisième étape (après 48 heures). Ces données suggèrent que la première étape reflète une structuration précoce de la trace mnésique. Dun autre côté, cette première étape est partiellement supprimée par la SMTr sans modification de la performance à plus long terme, suggérant que la première et la troisième étape sont au moins partiellement indépendantes. 4. Contrairement à lapprentissage dune tâche motrice simple (Muellbacher et coll. 2002), la consolidation de la trace mnésique survient très précocement pendant la phase dacquisition de la tâche. En effet, jusquà présent aucune interférence, quil sagisse dune nouvelle séquence apprise juste après la première (Walker et coll. 2003a, Korman et coll. 2007) ou dune SMTr (nos données, Robertson et coll. 2005), na permis de supprimer complètement la trace mnésique dune tâche motrice séquentielle. Le participant ne revient jamais à létat « naïf », initial, et dans le pire des cas, son niveau de performance est superposable à celui de la fin de lentraînement. 5. Le cortex moteur primaire intervient dans les étapes très précoces (30 premières minutes) de la consolidation de la trace mnésique qui succède à la phase dacquisition. La SMTr appliquée au niveau de M1 controlatéral à la main entraînée réduit la performance du sujet uniquement si elle est appliquée immédiatement après lentraînement et non 4 et 24 heures plus tard. Labsence de détérioration de la performance à ces 2 derniers délais démontre quil sagit dun effet spécifique de la SMTr sur la trace mnésique et non simplement dune réduction de la vitesse de frappe liée à une inhibition relative de la région cérébrale responsable de lexécution du mouvement. De plus, labsence deffet de la SMTr lorsque celle-ci est appliquée au niveau du cortex occipital immédiatement après lentraînement prouve quil sagit dun effet spécifique de la SMTr au niveau de M1. 6. La SMTr à haute fréquence appliquée immédiatement après lentraînement a le même effet que la SMT à basse fréquence sur lévolution de la trace mnésique au cours des 48 premières heures. Elle réduit lamélioration observée 30 minutes après lentraînement sans modifier la performance 48 heures plus tard. Cet effet délétère précoce potentiel sur lapprentissage moteur doit être pris en compte lors des études utilisant la SMT à haute fréquence à visée thérapeutique et en particulier en réhabilitation motrice chez les sujets cérébrolésés dautant quil nexiste actuellement pas de recommandation de sécurité en ce qui concerne la SMTr à haute fréquence chez ces patients. Nous avons donc démontré lexistence dune phase précoce (5 à 30 minutes après lentraînement) et transitoire (absente 4 heures après lentraînement) au cours de laquelle la performance qui suit un entraînement unique saméliore (« early boost »). La détérioration partielle de cette amélioration transitoire de performance par la SMTr suggère quà cette phase, la trace mnésique est distribuée dans un réseau cérébral incluant M1. Par contre, labsence de détérioration ultérieure de la performance (48 heures) et labsence deffet de la SMTr à 4 heures et 24 heures suggèrent que la consolidation dune tâche motrice récemment apprise dépend de circuits cérébraux cortico-cérébelleux et cortico-striataux dans lesquels M1 ne jouerait pas un rôle critique (Robertson et coll. 2005, Doyon et Benali 2005, Peigneux et coll. 2006). Il est possible que dans les premières minutes qui suivent un apprentissage séquentiel, les réseaux neuronaux impliqués dans cet apprentissage soient activés de façon globale (Albouy et coll. 2006). Dans ces conditions, la participation de M1 ne serait pas spécifique de la séquence apprise. Les corrélats cérébraux de cette phase devraient être étudiés en utilisant limagerie par résonance magnétique fonctionnelle (IRMf, voir perspectives).

Les propriétés de cristallisation et les interactions moléculaires intervenant dans des matières grasses naturelles, en létat ou modifiées, ainsi que dans leurs mélanges ont été caractérisées, et ceci dans le contexte de la mise sur le marché de produits alimentaires gras à teneur réduite en acides gras trans. En plus dune compréhension des propriétés de cristallisation, ce travail propose une modélisation offrant une possibilité de prédiction de propriétés de systèmes ternaires à partir des systèmes binaires correspondants. Enfin, la dernière partie de ce travail concerne une étude plus détaillée de la cinétique du polymorphisme et de lintersolubilité des constituants triglycéridiques dun composé majeur des formulations « low-trans » : lhuile de palme, ainsi que dun grand nombre de ses fractions (stéarines, oléines, superoléines et fractions intermédiaires). Lensemble des résultats démontre lintérêt de réaliser des diagrammes de phases pour létude du comportement dynamique de systèmes lipidiques et la nécessité de combiner plusieurs techniques pour caractériser ces systèmes hautement complexes et instables.