Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2014-02-07T19:30:13Z No. of bitstreams: 1 Isa Rita Brito de Moais Caracterização biológicae molecular das populações....pdf: 11985128 bytes, checksum: 42aef4c724b268ca4c6b0b0bec43eba9 (MD5) / Made available in DSpace on 2014-02-07T19:30:13Z (GMT). No. of bitstreams: 1 Isa Rita Brito de Moais Caracterização biológicae molecular das populações....pdf: 11985128 bytes, checksum: 42aef4c724b268ca4c6b0b0bec43eba9 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Salvador, BA, Brasil / Universidade Federal da Bahia. Faculdade de Medicina. Salvador, BA, Brasil / As cepas e clones do Trypanosoma cruzi apresentam diferentes aspectos de resistência e susceptibilidade aos quimioterápicos. Vários estudos vem sendo desenvolvidos para avaliar a resposta de diversas drogas em diferentes cepas protótipos dos Biodemas tipos I, II e III, de acordo com a caracterização biológica. Resultados vêm demonstrando que cepas protótipos do Biodema Tipo I (cepas Y e Perunana) apresentam uma alta susceptibilidade ao tratamento com Benzonidazol e Nifurtimox; cepas do Biodema Tipo II (protótipo: cepa 21SF) demonstram média susceptibilidade; as cepas do Biodema Tipo III (cepa Colombiana) são altamente resistentes. Considerando que as cepas do T.cruzi são populações multiclonais complexas, que diferem nas suas características genéticas e biológicas, clones de duas cepas do T.cruzi foram avaliadas com o objetivo de investigar se o uso da quimioterapia anti–T.cruzi poderia estar levando à seleção de clones resistentes que poderão ou não diferir nos seus caracteres biológicos e moleculares. No presente trabalho investigamos os caracteres biológicas e moleculares de clones da cepa Colombiana (Biodema Tipo III) e 21SF (Biodema Tipo II) do T. cruzi, isolados de animais tratados e não curados em comparação com clones isolados de animais não tratados, com o intuito de investigar se estes clones resistentes à quimioterapia apresentavam diferenças em suas características que pudessem estar justificando tal resistência. Para isto, 18 clones foram isolados de camundongos infectados da cepa Colombiana e 8 clones foram isolados de camundongos infectados com a cepa 21SF. Os resultados mostraram que as características biológicas dos clones isolados da cepa Colombiana foram mantidas; clones da cepa 21SF mostraram diferentes níveis de parasitemia quando comparados com a cepa parental. As características moleculares foram avaliadas a partir dos fragmentos do k-DNA de cada clone isolado, que foram submetidos à técnica de RFLP, utilizando as enzimas de restrição RSA I, HINF I e ECO RI. A análise dos fragmentos de restrição das cepas parentais e dos respectivos clones demonstrou grande similaridade entres os mesmos. A possibilidade de investigar a estrutura molecular utilizando outras técnicas moleculares, poderá contribuir para demonstrar diferenças na resistência dos clones isolados de animais tratados e não não curados, como visto na discussão. / Different strains and clones of Trypanosoma cruzi present differents degrees of susceptibility to treatment with chemotherapic drugs. Several studies have been developed to evaluate the response to different drugs concerning the strains prototypes of the Biodemes Types I, II and III according to the biological characterization. Results have shown that the strains prototypes of the Biodeme Type I (Y and Peruvian strains) disclosed a high susceptibility to treatment with Benznidazole and Nifurtimox; strains of the Biodeme Type II (prototype: the 21SF strain) showed a medium susceptibility; the strains of the Biodeme Type III (Colombian strain) were highly resistant. However a variability was detected according to the phase of infection in which the clones were isolated, and varied from 0% to 23,5% for the clones isolated in an early phase and 0% to 16.0% for those isolated in a late phase of infection. This indicates that the clonal populations could differently respond in different phases of treatment. In the present study we investigated the biological and molecular characters of clones of the 21SF strain (Biodeme Type II ) and of the Colombian strain (Biodeme Type III) isolated from mice treated with Benznidazole, but not cured , in comparison with clones isolated from untreated mice, with the objective of to investigate possible differences in the biological and molecular characteristics of these resistant clones. For that 18 clones were isolated from mice infected with the Colombian strain and 08 clones isolated from those infected with the 21SF strain. Results have shown that the biological characteristics were maintained in the Colombian strain; clones of the 21SF strain showed different levels of parasitemia as compared with the parental strain. This behavior is peculiar to clones isolated from the 21SF as shown in previous studies with clones isolated from untreated mice. The molecular characteristics were evaluated through the restriction fragment length polymorphism (RFLP) of the k DNA for each isolate clone, using restriction enzymes RSA I, HINF I and ECO RI. Analysis of restriction fragments from the clones an from the parental strains demonstrated a high similarity between them. The possibility of to investigate the molecular structure through other molecular techniques could contribute to disclose differences in the resistant clones isolated from treated uncured mice as seen in the discussion.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-08-01T18:23:08Z No. of bitstreams: 1 Milena Soares dos Santos Análise da composição clonal dos Streptococcus pneumoniae não susceptíveis a penicilina....pdf: 2536157 bytes, checksum: ee1fe922b8d1366faa0d4a8bea4d3b9f (MD5) / Made available in DSpace on 2012-08-01T18:23:08Z (GMT). No. of bitstreams: 1 Milena Soares dos Santos Análise da composição clonal dos Streptococcus pneumoniae não susceptíveis a penicilina....pdf: 2536157 bytes, checksum: ee1fe922b8d1366faa0d4a8bea4d3b9f (MD5) Previous issue date: 2010 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / O Streptococcus pneumoniae permanece como principal causa de doenças infecciosas que conduzem a elevada morbi-mortalidade em todas as faixas etárias, principalmente nas crianças. Desde a década de 1990, a resistência antimicrobiana deste microrganismo tem aumentado mundialmente, representando mais de 30% de resistência à penicilina em todos os isolados de doença pneumocócica invasiva em algumas áreas geográficas. Neste estudo, relatamos os casos identificados através de uma vigilância ativa para a meningite bacteriana em Salvador, Bahia, no período de janeiro de 1996 a dezembro de 2007. Para avaliar o perfil de susceptibilidade aos antimicrobianos dos isolados dos pacientes com meningite por S.pneumoniae, utilizamos a microdiluição em caldo e isolados com CIM de penicilina ≥ 0.125μg/mL foram considerados como não-susceptíveis à penicilina (PNSP). A diversidade clonal foi estudada por Box-A PCR, PFGE e MLST e a distribuição de pili foi investigada em 133 amostras, selecionadas de forma aleatória em cada grupo clonal, através das técnicas de PCR e seqüenciamento do gene rlrA. Um total de 748 pacientes com meningite por S.pneumoniae foi identificado durante os 12 anos de vigilância. Foram encontrados 135 (19%) isolados de S. pneumoniae não-susceptíveis à penicilina sendo que destes, 85 (63%) eram crianças <5 anos de idade e 28 (20,7%) dos pacientes apresentavam alguma doença precedendo a meningite. A incidência média anual de PNSP foi estimada em 2,47 por 100.000 habitantes para todas as faixas etárias, 1,69 casos/100.000 habitantes para crianças menores de 5 anos e 1,37 casos/100.000 habitantes para crianças menores de 1 ano. A taxa de letalidade obtida para todas as idades foi de 39,2%. Os sorotipos mais prevalentes entre os isolados de PNSP foram: 14 (46,7%; 63/135) 23F (17,8%; 24/135), 6B (14,8%; 20/135), 19F (8,1%; 11/135) e 19A (4,4%; 6 / 135). Os isolados do sorotipo 14 foram identificados como o grupo clonal predominante 32,6% (44/135) e foram caracterizados como ST66 e como ST156 com alta resistência à ceftriaxona. Os outros sorotipos apresentaram maior diversidade clonal e novos STs foram encontrados, entre outros sorogrupos. Foram detectados 22% (29/133) de isolados portadores de pili, independente de composição clonal ou perfil de resistência. Baseada na vacina pneumocócica conjugada 10-valente, prevista para ser implementada no Brasil este ano, esperamos 89% de proteção contra PNSP em crianças menores de 5 anos de idade. As alterações previstas na população pneumocócica, ao longo dos anos após a implementação desta vacina, ressaltam a importância do monitoramento através de vigilância ativa. / Streptococcus pneumoniae remains an important cause of infectious diseases leading to high morbidity and mortality in all age groups, especially in children. Since the 1990s, resistance of this organism to penicillin has emerged worldwide accounting for >30% of all invasive pneumococcal isolates in some geographic areas. In this study, active surveillance for bacterial meningitis was performed from January 1996 to December 2007. Antimicrobial susceptibility testing used broth microdilution and isolates with penicillin MIC ≥ 0.125μg/mL were considered penicillin non-susceptible. Clonal diversity was studied by Box-A PCR, PFGE and MLST and pili detection was determinated by PCR and sequencing of rlrA gene. A total of 748 patients with pneumococcal meningitis were identified during 12 years of surveillance. We found 135 (19%) S. pneumoniae isolates to be penicillin-nonsusceptible, which 85 (63%) were children < 5 years age and 28 (20.7%) patients had previous acute illness. The annual incidence of PNSP was estimated to 2.47 per 100,000 for all age groups, 1.69 cases/100.000 population for children younger than 5 years, and 1.37 cases/100.000 inhabitants for children under 1 year. The case-fatality rate obtained for all ages was 39.2%. The most prevalent serotypes PNSP isolates were among the 14 (46.7%; 63/135), 23F (17.8%; 24/135), 6B (14.8%; 20/135), 19F (8.1%; 11/135) and 19A (4.4%; 6/135). Serotype 14 isolates were identified as the predominant clonal group [32.6% (44/135)] and were characterized as ST66 and as ST156 with high resistance to ceftriaxone. The other serotypes were more diverse and new ST´s were found among others serogroups. We detected 22% (29/133) of pili positive among the isolates, independently of clonal patterns or susceptibility profile. Based on 10-valent pneumococcal vaccine, which will be implemented in Brazil in 2010, we expect 89% protection against PNSP in children < 5 years of age. Changes in the pneumococcal population over the coming years following implementation of this vaccine should be monitoring throughout active surveillance.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2014-09-18T13:52:18Z No. of bitstreams: 1 Eder Silva dos Anjos. Caracterização...2013.pdf: 1214899 bytes, checksum: 285b9e9fed3b500c66d7173ea5a7c440 (MD5) / Made available in DSpace on 2014-09-18T13:52:18Z (GMT). No. of bitstreams: 1 Eder Silva dos Anjos. Caracterização...2013.pdf: 1214899 bytes, checksum: 285b9e9fed3b500c66d7173ea5a7c440 (MD5) Previous issue date: 2013 / Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Salvador, BA, Brasil / O advento das vacinas pneumocócicas conjugadas veio contribuir de forma decisiva para a redução da incidência dos casos de doença invasiva por S. pneumoniae em vários países do mundo. Em contrapartida, tem-se verificado um aumento de casos decorrentes de sorotipos não vacinais, que escapam da vacina e reduzem o seu efeito a partir da expansão de clones pré-existentes com consequente substituição de sorotipos e/ou do fenômeno de troca capsular (capsular switching). No Brasil, a vacina conjugada 10-valente (PCV10) foi introduzida no calendário nacional de imunização a partir de 2010. Este estudo teve como objetivo caracterizar através de técnicas fenotípicas e moleculares os sorotipos não-vacinais (SNVT) de S.pneumoniae, isolados de pacientes com meningite nos períodos anterior (janeiro/2008 - junho/2010) e posterior (julho/2010 - dezembro/2012) à implementação da vacina pneumocócica conjugada 10-valente (PCV10), na cidade de Salvador, Bahia. Os isolados de S. pneumoniae foram identificados através de métodos microbiológicos clássicos e a determinação do tipo capsular foi realizada através da técnica de Multiplex-PCR e/ou reação de Quellung. A sensibilidade a oito antimicrobianos foi realizada através da técnica de microdiluição em caldo e a caracterização genotípica por intermédio das técnicas de PFGE e MLST. Foram identificados 170 casos de meningite pneumocócica durante a vigilância epidemiológica realizada no Hospital Couto Maia, em Salvador, com 148 apresentando cultura positiva para S. pneumoniae a partir do líquor e/ou hemocultura. A incidência da meningite pneumocócica reduziu de 0,9/100.000 habitantes (2008) para 0,36/100.000 habitantes (2012). No período pré-vacinal, os SNVT mais frequentes foram: 3 (n=6; 12%), 19A (n=4; 8%), 6A (n=4, 8%); no período pós-vacinal os SNVT 12F (n=6; 22,2%), 10A (n=3; 11,1%), 15B (n=2; 7,4%) e 18B (n=2; 7,4%) foram os mais frequentes. Cerca de 78% dos isolados apresentaram resistência a um ou mais antibióticos. A não susceptibilidade à penicilina foi encontrada nos sorotipos 19A (3 isolados), 9N (1 isolado) e 12F (1 isolado). Por PFGE, foi observada uma grande diversidade genética com a maioria (66,2%) dos isolados pertencendo a grupos não clonais. O grupo clonal X foi composto por dois isolados do sorotipo 19A (ST2878), do período pré-vacinal, não susceptível à penicilina. A técnica de MLST realizada em 26 isolados permitiu a identificação de quatro novos STs e apresença de STs (ST180, ST193 e ST218) genotipicamente semelhantes aos clones mundiais Netherlands3-31, Greece21-30 e Denmark12F-34. É necessária a continuidade da vigilância epidemiológica da meningite pneumocócica, visando avaliar os efeitos benéficos da vacinação e a dinâmica da distribuição de sorotipos em nossa região. / The licensure and subsequent widespread use of pneumococcal conjugate vaccines have contributed for the reduction in the overall incidence of invasive pneumococcal disease worldwide. However, the emergence of Streptococcus pneumoniae nonvaccine serotypes (SNVT), which escape from the vaccine by the expansion of pre-existing clones following serotype replacement and/or by capsular switching is a matter of concern. In 2010, Brazil introduced the 10-valent conjugate pneumococcal vaccine (PCV10) into its routine National Immunization Program. Our aim was to characterize the phenotypic and genotypic profile of S. pneumoniae non-vacine serotypes (SNVT) isolated from patients with meningitis before (January 2008 – June 2010) and after (July 2010 – December 2012) the introduction of PCV10 in Salvador, Bahia. The pneumococcal isolates were identified by classical microbiological methods and submitted to capsular deduction by multiplex-PCR and/or Quellung reaction. The antimicrobial susceptibility was performed the broth microdilution method. The genotypic profile was assessed by PFGE and MLST. We identified 170 cases of pneumococcal meningitis during the epidemiological surveillance at the Hospital Couto Maia, in Salvador, with 148 showing positive culture for S. pneumoniae from the cerebrospinal fluid and/or blood culture. The incidence of pneumococcal meningitis decreased from 0.9/100.000 (2008) to 0.36/100.000 inhabitants (2012). In the pre-vaccine period the most frequent SNVT were: 3 (n=6, 12%), 19A (n=4, 8%), 6A (n=4, 8%). In the post-vaccine period, the SNVT 12F (n=6, 22.2%), 10A (n=3, 11.1%), 15B (n=2, 7.4%) and 18B (n=2, 7.4%) were the most prevalent. About 78% of the isolates were resistant to one or more antibiotics. The non-susceptibility to penicillin was found among serotypes 19A (3 isolates), 9N (1 isolate) and 12F (1 isolate). By PFGE, a wide genetic diversity was found with the majority of the isolates (66.2%) belonging to non-clonal groups. The clonal group X comprised two isolates of the serotype 19A (ST2878) from the pre-vaccine period presenting non-susceptibilty to penicillin. MLST assay performed in 26 isolates allowed the identification of four new STs and the presence of STs (ST180, ST193 and ST218) with genotipic similarities of the worldwide clones Netherlands3-31, Greece21-30 and Denmark12F-34. Continued surveillance studies are necessary to evaluate the benefits of vaccination and the serotype dynamics in our region

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-07T13:37:52Z No. of bitstreams: 1 PGCS16MA148.pdf: 913483 bytes, checksum: 3c99a555d7d1016ce10ddda1718d4f23 (MD5) / Made available in DSpace on 2018-03-07T13:37:52Z (GMT). No. of bitstreams: 1 PGCS16MA148.pdf: 913483 bytes, checksum: 3c99a555d7d1016ce10ddda1718d4f23 (MD5) Previous issue date: 2016-07-14 / FAPESC / Erva-mate (Ilex paraguariensis St. Hil.) has great economic importance in southern Brazil, however there are few studies that address the response of this crop to fertilization. The objective of this work was to evaluate the erva-mate response to the application of doses of phosphorus (P) and sulfur (S) in the establishment, growth and nutrition of two clones (F1 and F2) during the orchard planting. Four experiments were installed, two in Itaiópolis - SC and two in Três Barras - SC. At each site an experiment was designed to evaluate the erva-mate response to P and another to S. In experiments with P it were tested five P rates (0, 2.6, 9, 13.6, and 18 kg ha-1 of P2O5) and two clones, and in the experiments for S were tested four doses of S (0, 1.2, 2.4 and 3.6 kg ha-1 S-SO4) and two clones. The treatments were arranged in a factorial design with split-plots and arranged in a randomized block design with four replications. In September 2013, the soil was prepared in the planting row and the planting was done at a spacing of 2 x 2.5 m. The same dose applied at planting, was also applied after planting, superficially. The fertilization after planting was fractionated into three periods: January / 2014, September / 2014 and January / 2015. In August 2015 it were evaluated the growth in height and productivity of sheet components, twig, thick branch and commercial erva-mate; and the P and S content in the plant tissue. The P and S content available in the soil in the 0-20 cm layer were evaluated 12 months after planting. There was no effect of P fertilization doses in the two locations, possibly due to the high content of P in the soil. Conversely, it was observed better performance of F2 clone under sulphur fertilization / O cultivo da erva-mate (Ilex paraguariensis St. Hil.) apresenta grande importância econômica na região sul do Brasil. Contudo, poucos são os trabalhos que abordam a resposta desta cultura à adubação. O objetivo deste trabalho foi avaliar a resposta da planta à aplicação de doses de fósforo (P) e enxofre (S) no estabelecimento, crescimento e nutrição de dois clones de erva-mate (F1 e F2) em fase de implantação do erval. O trabalho foi constituído de quatro experimentos, dois instalados no município de Itaiópolis – SC e dois em Três Barras – SC. Em cada local foi instalado um experimento com P e outro com S. Nos experimentos com P foram testadas cinco doses (0, 2,6, 9, 13,6, e 18 kg ha-1 de P2O5) e dois clones, e nos experimentos de S foram testadas quatro doses (0, 1,2, 2,4 e 3,6 kg ha-1 de S-SO4) e dois clones. As mudas foram plantadas em setembro de 2013, com espaçamento de 2 x 2,5 m. A mesma dose aplicada no plantio, também foi aplicada pós-plantio, superficialmente sendo fracionada em três épocas: em janeiro e setembro/2014 e janeiro/2015. Em agosto de 2015 foi avaliado o crescimento em altura e produtividade dos componentes folha, galho fino, galho grosso e erva-mate comercial (folha+galho fino); e P e S do tecido vegetal dos componentes. Os teores de P e S disponíveis no solo na camada de 0-20 cm foram avaliados 12 meses após o plantio das mudas. Não houve resposta à adubação fosfatada para a cultura da erva-mate nas localidades Itaiópolis e Três Barras, possivelmente pela alta disponibilidade de P antes da implantação do experimento, que impediu a formação da curvas de resposta. Por outro lado, houve resposta ao enxofre, principalmente do clone F2

Le cancer du sein est un problème majeur de santé public dont l'incidence est en permanente augmentation. La mortalité est le plus souvent due aux métastases. Les études concernant PTPL1, la plus grande des tyrosines phosphatases cytoplasmiques, ont montré que PTPL1 présente les caractéristiques de suppresseur de tumeur. PTPL1 se trouve mutée dans plusieurs types de cancers et son expression est un marqueur de bon pronostique dans les tumeurs mammaires. Mon laboratoire a également montré que PTPL1 participe à l'effet pro-apoptotique des anti-oestrogènes dans les cellules tumorales hormono dépendantes en déphosphorylant IRSl, le substrat d'IGF1-receptor freinant ainsi la voie PI3K/AKT. PTPL1 régule également la croissance, l'invasion et l'adhésion dans les cellules cancéreuses mammaires peu agressives MCF7.Nous avons établi un modèle cellulaire de clones isogéniques capables d'exprimer PTPL1 ou ses mutants d'une manière inductible dans les cellules cancéreuses mammaires invasives MDA-MB-231. D’une part, nous avons montré un impact négatif de l'expression de PTPL1 sur le phénotype invasif de ces cellules. D'une manière intéressante, le mutant catalytiquement inactif a montré un comportement similaire à celui du contrôle de transfection. Ceci montre l'importance de l'activité catalytique de PTPL1 dans l'inhibition du phénotype agressif. Nous testons maintenant in vivo la tumorigenicité des clones chez les souris athymique.D'autre part, nous avons étudié par protéomique comparative (SILAC) la tyrosine phosphorylation globale des protéines cellulaires dans les cellules MCF-7 et MDA-MB-231 exprimant ou non PTPL1. Parmi les protéines identifiées nous retrouvons des acteurs des différentes voies de signalisations connues dans la littérature pour être impactées par PTPL1 , mais de manière remarquable plus du quart des protéines identifiées sont liées aux jonctions cellulaires ou à leur régulation. Nous avons donc étudié l'effet de la phosphatase sur les jonctions cellulaires et montré que la surexpression de PTPL1 favorise la formation d'agrégats cellulaire en culture 3D, augmente la stabilité des contacts cellulaire en vidéo-microscopie, relocalise la desmogléïne aux jonctions cellulaires et induit une réexpression de la E cadhérine aux niveau du contact cellule/cellule dans les cellules MDA-MB-231.Les jonctions et la polarité cellulaires sont très importantes en cancérologie en particulier dans le processus invasif qui est la première étape de la dissémination métastatique donc il serait maintenant important d'identifier les substrats directs de PTPL1 pour élucider la signalisation de PTPL1 vers les jonctions et proposer de nouvelles cibles thérapeutique. / The regulation of breast tumor aggressiveness by Protein Tyrosine Phosphatase PTPL1/ PTPN13Breast cancer is a major problem for public health of which the incidence continues to increase. Its mortality is often linked to metastasis formation. Studies on PTPL1, the largest protein tyrosine phosphatase, have shown that it presents the characteristics of a tumor suppressor gene. PTPL1 is mutated in several types of cancers and its expression is associated with good prognostic in prostate and breast cancers. My team has shown that PTPL1 mediates the pro apoptotic effect of anti-estrogen in hormone-sensitive tumor cells by dephosphorylating IRS1, Insulin growth factor-1 receptor substrate, thus blocking PI3K/Akt pathway. In addition, PTPL1 regulates the growth, the invasion, and the adhesion of low aggressive breast tumor cells MCF-7.Our team established an isogenic cellular model capable of expressing PTPL1 or its mutants (phosphatase-dead and substrate-trapping mutants) in an inducible fashion in invasive cells. We showed that functional PTPL1 expression has a negative impact on cell aggressive phenotypes. Interestingly, the phosphatase-dead mutant exhibits the same behavior as the transfection control. This evidences that PTPL1 activity is crucial for the inhibition of aggressiveness. We are currently testing the clones tumorigenicity in athyemic mice.Furthermore, we conducted a comparative proteomic (SILAC) in order to study the global tyrosine phosphatome in MCF-7 and MDA-MB-231 cells with or without PTPL1. Our findings suggest that PTPL1 regulates the phosphorylation of proteins involved in different signaling pathways already described in the literature to be impacted by PTPL1. Remarkably, the quarter of proteins identified belong to cell junction structure or regulation. We then studied the impact of this phosphatase on cell junctions and showed that PTPL1 overexpression enhances cell aggregate formation in 3D culture, increases cell contact stability, relocates desmoglein to the cell junctions, and induces E-cadherin re-expression at the level of cell-cell contacts in MDA-MB-231 cells.Cell junctions and polarity are very important in oncology and particularly in the invasive process which is the first step in the metastatic dissemination. Our ongoing work focuses on identifying direct substrates for PTPL1 in order to elucidate the underlying PTPL1 signal leading to cell junctions and consequently propose a novel therapeutic targets.

A borracha natural é uma matéria-prima importante na fabricação de urna variedade de artefatos. Atualmente, o Estado de São Paulo é o maior produtor de borracha natural do país. Para as indústrias de transformação de materiais poliméricos é importante que a matéria-prima tenha qualidade e uniformidade. Neste sentido, esse trabalho avaliou as variações intra e interclonais e os efeitos do tipo de coagulação e do porta-enxerto nas propriedades da borracha natural, visando à avaliação da uniformidade da mesma. Foram estudados diferentes clones de seringueira como o RRIM 600, IAN 873 e GT 1. O projeto foi desenvolvido em colaboração com o Instituto Agronômico de Campinas (IAC), que vem avaliando a interação genótipo versus ambiente de clones seringueira [Hevea brasilienses (Willd. Ex Adr. de Juss.) Muell. Arg.] recomendados para o plantio no Estado de São Paulo. A avaliação da borracha natural foi realizada através de ensaios padrões e técnicas de espectroscopia na região do infravermelho, calorimetria diferencial de varredura (DSC), análise termogravimétrica (TG), análise termo dinâmico-mecânica (DMTA) e nanoindentação. Os resultados mostraram que as propriedades da borracha são uniformes dentro de um mesmo clone. Já o estudo da variação interclonal das propriedades avaliadas mostrou que existem diferenças significativas entre as borrachas dos clones para todas as propriedades estudadas. As propriedades da borracha são uniformes independentemente do porta-enxerto (RRIM 600, PB 235, SNS, GT 1, IAN 873), utilizado nos clones, com exceção da viscosidade Mooney. No estudo do efeito dos tratamentos de estocagem e coagulação, os resultados mostraram que a coagulação química do látex resulta em borrachas com altos valores de plasticidade e viscosidade. Já para as amostras coaguladas espontaneamente, observou-se que aquelas estocadas por períodos não superiores a 7 dias apresentaram melhores propriedades de plasticidade, viscosidade e PRI, de acordo com as normas da ABNT e da literatura internacional. No estudo das propriedades da borracha natural via técnica de nanoindentação, concluiu-se que a técnica é uma ferramenta que deve ser melhor explorada para a determinação das propriedades da borracha em nanoeseala. De uma forma geral, o trabalho desenvolvido nesta tese de doutorado apresenta resultados inéditos de um estudo sistemático sobre a variação das propriedades da borracha natural e vem contribuir com mais uma etapa do estudo que vem sendo feito pela Embrapa e pelo IAC de avaliação dos aspectos agronômicos da seringueira e das propriedades do produto pós-colheita / Natural rubber is an important raw material used for manufacturing a large variety of products. Nowadays the state of São Paulo is the largest producer of natural rubber in Brazil. Polymeric material industries need raw materiais with high quality and uniformity. In this sense, the proposal of this work was to study and evaluate the properties of natural rubber in order to assess the quality of the product. In the study reported here, the intra and inter dona! variations were analyzed systematically. In addition, the effect of rootstocks and methods of coagulation on the properties of natural rubber were investigated. This project was developed in collaboration with Agronomic Institute of Campinas that investigates the agronomic aspects of rubber tree [Hevea brasilienses (Willd. Ex Adr. de Juss.) Muell. Arg.] clones for wide-scale plantation in various regions of São Paulo State. The evaluation of natural rubber\'s quality was done using standard methods of industry and other techniques such as infrared spectroscopy, differential scanning calorimeter (DSC), thermal gravimetric analyzer (TGA), dynamic mechanical analyzer (DMTA) and nanoindentation. Results showed that the properties of natural rubber do not change among trees of the same clone. Besides, it was found that the rootstocks (RRIM 600, PB 236 SNS, GT 1 and IAN 873) have no marked influence in the properties of natural rubber clones (RRIM 600 and PB 235). On the other hand, the results of interclonal study have shown highly and significant variations among clones for the rubber properties evaluatcd. Other investigation carried out was the effect of coagulation and storage. Results showed that chemical coagulation and larger periods of storage yields rubber with high values of plasticity and viscosity. Nanoindentation studies of natural rubber demonstrated that this technique might be improved to study elastomers at nanoscale levei. In this sense, the work developed shows a systematic study on the evaluation of natural rubber clones that has not previously performed. It contributes with one more step in the study that has been developed by Embrapa and IAC to improve the quality of natural rubber in São Paulo

Este trabalho teve por objetivo estudar o desempenho mecânico e térmico de compostos de borracha natural de diferentes tipos de clones (GT 1, IAN 873, PB 235 e RRIM 600). A qualidade do látex de borracha natural dos diferentes clones de seringueiras (Hevea brasiliensis) recomendados para o Estado de São Paulo, foram avaliadas por ensaios padrões (plasticidade Wallace, PRI, viscosidade Mooney, % de cinzas, extrato acetônico e % de nitrogênio). Estas borrachas foram formuladas em cilindro e vulcanizadas com tempos de 5, 7 e 9 minutos. A avaliação do desempenho mecânico e térmico dos diferentes compostos de borracha natural foram realizados por Calorimetria Diferencial de Varredura (DSC), Análise Termogravimétrica (TGA), propriedades mecânicas de tração e dureza, caracterização por Análise Térmica-Dinâmico-Mecânica (DMT A), Microscopia Eletrônica de Varredura (MEV) e Espectroscopia no Infravermelho com Transformada de Fourier (FTIR). O desempenho mecânico e térmico foram comparados e correlacionados com as características da borracha crua. Os valores obtidos para temperatura de transição vítrea (Tg), foram inferiores a -56&#176C para as borrachas vulcanizadas e de -62&#176C para as borrachas cruas, a blenda crua apresentou um menor valor (92,5&#176C), devido a uma maior mastigação para a homogeneização da amostra, não apresentando grandes variações em relação ao tempo de vulcanização e ao tipo de clone. Os ensaios de tração mostraram que um dos clones mais produtivos (RRIM 600) obteve o melhor desempenho mecânico. As borrachas formuladas, obtiveram no ensaio de dureza valores próximos de 60 Shore A, não variando em relação ao tempo de vulcanização e ao tipo de clone. Todas as amostras estudadas ficaram dentro dos padrões de qualidade exigidos. De acordo com os resultados obtidos neste trabalho e com a literatura, todos os clones estudados, incluindo os mais produtivos (PB 235 e RRIM 600) podem ser utilizados nas indústrias de artefatos de borracha separadamente ou na forma de blenda. / The objetive of this work was to study the mechanical and thermal performance of natural rubber composites of different types of clones (GT 1, IAN 873, PB 235 and RRIM 600). The latex quality of different natural rubber dones (Hevea brasiliensis) recommended for plantation in the State of São Paulo were evaluated by standards methods (Wallace plasticity, PRI, Mooney viscosity, content percentage, acetonic extract and nitrogen content percentage). These rubbers were formulated and prepared in a mill and vulcanized at different times (5, 7 and 9 min.). The evaluation of the mechanical and thermal performance of different natural rubber composites was carried out by differential scanning calorimetry (DSC), thermo gravimetry (TGA), mechanical properties (tensile and hardness tests), dynamic mechanic thermal analysis (DMTA), scanning electron microscopy (SEM) and Fourrier transform infrared spectroscopy (FTIR). The mechanical and thermal performance were compared and correlated with the characteristics of the raw rubber. The values obtained for glass transistion temperature (Tg) were found to be bellow -56&#176C for vulcanized rubbers and of 62&#176C for raw rubbers, without having great variations in relation to the vulcanization time and type of done. The tensile tests showed that the best performance was obtained for the most productive clone (RRIM 600). Hardness test values obtained were close to 60, without varying in relation to the vulcanization time and the type of clone. Ali the samples studied were in agreement with standard specifications required for application in the rubber industry. According to these results and related Iiterature, all clones including the most productive ones (PB 235 and RRIM 600) can be used in the rubber industry in blended or unblended forms.

Many problems in the biological sciences reduce to questions of genetic evolution. Entire classes of medical pathology, such as malignant neoplasia or infectious disease, can be viewed in the light of Darwinian competition of genomes. With the benefit of today's maturing sequencing technologies we can observe and quantify genetic evolution with nucleotide resolution. This provides a molecular view of genetic material that has adapted, or is in the process of adapting, to its local selection pressures. A series of problems will be discussed in this thesis, all involving the mathematical modeling of genomic data derived from clonally evolving populations. We use a variety of computational approaches to characterize over-represented features in the data, with the underlying hypothesis that we may be detecting fitness-conferring features of the biology. In Part I we consider the cross-sectional sampling of human tumors via RNA-sequencing, and devise computational pipelines for detecting oncogenic gene fusions and oncovirus infections. Genomic translocation and oncovirus infection can each be a highly penetrant alteration in a tumor's evolutionary history, with famous examples of both populating the cancer biology literature. In order to exert a transforming influence over the host cell, gene fusions and viral genetic programs need to be expressed and thus can be detected via whole transcriptome sequencing of a malignant cell population. We describe our approaches to predicting oncogenic gene fusions (Chapter 2) and quantifying host-viral interactions (Chapter 3) in large panels of human tumor tissue. The alterations that we characterize prompt the larger question of how the genetics of tumors and viruses might vary in time, leading us to the study of serially sampled populations. In Part II we consider longitudinal sampling of a clonally evolving population. Phylogenetic trees are the standard representation of a clonal process, an evolutionary picture as old as Darwin's voyages on the Beagle. Chapter 4 first reviews phylogenetic inference and then introduces a certain phylogenetic tree space that forms the starting point of our work on the topic. Specifically, Chapter 4 describes the construction of our projective tree space along with an explicit implementation for visualizing point clouds of rescaled trees. The Chapter finishes by defining a method for stable dimensionality reduction of large phylogenies, which is useful for analyzing long genomic time series. In Chapter 5 we consider medically relevant instances of clonal evolution and the longitudinal genetic data sets to which they give rise. We analyze data from (i) the sequencing of cancers along their therapeutic course, (ii) the passaging of a xenografted tumor through a mouse model, and (iii) the seasonal surveillance of H3N2 influenza's hemagglutinin segment. A novel approach to predicting influenza vaccine effectiveness is demonstrated using statistics of point clouds in tree spaces. Our investigations into clonal processes may be extended beyond naturally occurring genomes. In Part III we focus on the directed clonal evolution of populations of synthetic RNAs in vitro. Analogous to the selection pressures exerted upon malignant cells or viral particles, these synthetic RNA genomes can be evolved against a desired fitness objective. We investigate fitness objectives related to reprogramming ribosomal translation. Chapter 6 identifies high fitness RNA pseudoknot geometries capable of inducing ribosomal frameshift, while Chapter 7 takes an unbiased approach to evolving sequence and structural elements that promote stop codon readthrough.

The infestation of twelve selected clones of alfalfa by the alfalfa seed chalcid was measured. The free sterol content of the stems, leaves, f lowers and pods of these clones was determined. A check was made to see if there was a correlation between the sterol content and the chalcid infestation. Differences were found among t he clones in the sterol content for each plant part. There were also significant differences in percent chalcid infestation in the 12 clones. Duncan ' s New Multiple Range Test pointed out which clones differed Significantly from the others. Using linear regression analysis, the correlation coefficient of the comparison between the sterol content and the chalcid infestation was obtained. There was a signtflcant negative correlation between the sterol content of the flower and the percent chalcid infestation. No significant correlation was found between t he sterol content of the stems, leaves or pods and the percent chalcid infestation.