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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Identification de nouveaux miARN régulateurs de la mucine MUC1, détermination de leurs rôles fonctionnels dans la cancérogenèse pancréatique et dans la chimiorésistance / Identification of new miRNA regulating MUC1 and determination of their functional biological roles and involvement in drug resistance of pancreatic cancer

Tréhoux, Solange 15 January 2015 (has links)
La mucine MUC1 est une oncoprotéine transmembranaire dont la surexpression dans 90% des adénocarcinomes pancréatiques a été associée à un mauvais pronostic. MUC1 est impliquée dans la transduction des signaux intracellulaires et dans les interactions cellulaires permettant de conférer aux cellules tumorales des propriétés accrues en termes de prolifération et d’invasion cellulaire. De plus il a été montré un rôle important de MUC1 dans la chimiorésistance à la gemcitabine, et dans la transition épithélio-mésenchymateuse des cellules cancéreuses pancréatiques. De manière intéressante il a pu être montré que MUC1 pouvait être internalisée et localisée dans le compartiment nucléaire afin d’agir comme un co-activateur transcriptionnel permettant de moduler l’expression de nombreux gènes comme ceux de la voie Wnt/β-caténine, les cibles de Stat1/3 ou le cluster miR-200c/miR141. De plus, il a été démontré que MUC1 pouvait être régulé de façon épigénétique, par méthylation de son promoteur, par acétylation des histones et par les miARN.Notre objectif a été d’étudier l'inhibition de MUC1 par des miARN dérégulés dans le cancer pancréatique, afin de proposer une nouvelle stratégie thérapeutique innovante dans le but de ralentir la progression de ce cancer. Nous avons sélectionné des miARN pouvant cibler la mucine MUC1 aussi bien au niveau de son 3’UTR, de son 5’UTR ou de sa région codante par l'utilisation des bases de données miRanda, miRWalk et TargetScan. Afin d’affiner cette sélection, nous avons ensuite retenu seulement ceux étant dérégulés dans le cancer pancréatique en étudiant leur expression dans des lignées cellulaires cancéreuses pancréatiques humaines ainsi que dans un modèle murin transgénique de cancérogenèse pancréatique et dans les tissus de patients atteints d'adénocarcinome pancréatique.Nous avons dans un premier temps mis en évidence que parmi les miARN sélectionnés, la surexpression de miR-29a, miR-183, miR-200a, miR-330-5p, miR-876-3p et miR-939 entraînait une diminution de l'expression protéique de MUC1. En établissant le profil d'expression des miARN dans les trois modèles de cancer pancréatique dont nous disposions, nous avons pu mettre en évidence une dérégulation globale de miR-29a et miR-330-5p dans les lignées cellulaires cancéreuses pancréatiques humaines ainsi que chez les patients atteints d'adénocarcinome pancréatique, et une dérégulation plus spécifique pour les autres miARN. Nous avons alors pu mettre en évidence que parmi l'ensemble des miARN sélectionnés, seuls les miARN miR-29a et miR-330-5p avaient la capacité d’interagir avec l'ARNm de MUC1 au niveau de son 3’UTR. Nous avons donc entrepris dans un second temps d’étudier le rôle de miR-29a et miR-330-5p dans le cancer du pancréas. Pour cela, nous avons utilisé une stratégie transitoire de surexpression et d'inhibition des miARN et une stratégie stable en réalisant des lignées surexprimant les miARN ainsi qu’une lignée déficiente en MUC1. Nous avons pu mettre en évidence que la surexpression de miR-29a et miR-330-5p, permettait de ralentir la prolifération cellulaire, la migration, l'invasion cellulaire, la croissance tumorale et augmentait la chimiosensibilité des cellules cancéreuses pancréatiques à la gemcitabine. En conclusion, l'ensemble de ces données a permis de mettre en évidence un ensemble de miARN dérégulés dans le cancer du pancréas ayant la capacité de réguler négativement l'expression protéique de la mucine MUC1. Nous avons également montré que miR-29a et miR-330-5p étaient les seuls à réguler directement l'expression de MUC1 et qu’ils agissaient comme des suppresseurs de tumeurs en altérant les propriétés biologiques des cellules cancéreuses pancréatiques, in vitro et in vivo. Ces données nous permettent de proposer ces deux miARN comme une nouvelle piste thérapeutique potentielle pour le traitement de ce cancer. / The mucin MUC1 is a transmembrane oncoprotein overexpressed in 90% of pancreatic adenocarcinoma and associated with a poor prognosis. MUC1 is involved in cell signaling and cell interaction to enhanced tumor cell properties like cell proliferation and invasion. Furthermore it has been shown an important role of MUC1 in chemoresistance to gemcitabine, the basic treatment of pancreatic cancer, and in the epithelial-mesenchymal transition of pancreatic cancer cells. Interestingly it has been shown that MUC1 could be internalized and localized in the nuclear compartment to act as a transcriptional coactivator to modulate the expression of many genes such as the Wnt/β-catenin, the targets of Stat1/3 or the miR-200c/miR141 cluster. Furthermore, it has been shown that MUC1 is regulated by epigenetics: by methylation of the promoter, histone acetylation and by miRNAs in breast and ovarian cancer.Our aim was to study the inhibition of MUC1 by miRNAs deregulated in pancreatic cancer, to propose a new innovative therapeutic strategy to slow down progression of this cancer.We selected miRNAs targeting the mucin MUC1, in its 3\\\'UTR, its 5\\\'UTR or its coding region by using databases such as Miranda, miRWalk and TargetScan. To refine this selection, we then selected only those being deregulated in pancreatic cancer by studying their expression in human pancreatic cancer cell lines, tissues from patients with pancreatic adenocarcinoma and transgenic mouse model of early pancreatic carcinogenesis.We initially demonstrated that among the selected miRNAs, overexpression of miR-29a, miR-183, miR-200a, miR-330-5p, miR-and miR-939 876-3p led to a decrease of MUC1 protein expression. By establishing the miRNA expression profile in the three models of pancreatic cancer that we had, we were able to demonstrate an overall deregulation of miR-29a and miR-330-5p in human pancreatic cancer cell lines and in patients with a pancreatic adenocarcinoma, and a more specifically deregulation for the other miRNAs.We were then able to show that among the selected miRNAs, only miRNAs miR-29a and miR-330-5p had the ability to interact with MUC1 mRNA on its 3\\\'UTR. We therefore undertook to study the role of miR-29a and miR-330-5p in pancreatic cancer. For this, we used a transient strategy to overexpress or inhibit miRNAs and stable cell lines overexpressing the miRNA as well as a deficient cell line for MUC1. We were able to show that overexpression of miR-29a and miR-330-5p slowed down cell proliferation, migration, cell invasion, tumor growth and increased chemosensitivity of pancreatic cancer cells to gemcitabine.In conclusion, all these data allowed us to identify a set of deregulated miRNAs in pancreatic cancer which have the ability to decrease the mucin MUC1 protein expression level. We also showed that miR-29a and miR-330-5p were the only ones that can regulate the expression of MUC1 directly and act as tumor suppressors by altering the biological properties of pancreatic cancer cells in vitro and in vivo. These data allow us to propose these two miRNAs as a new potential therapeutic approach for the treatment of this cancer.
22

Identificação de micrornas diferencialmente expressos em células pulmonares e pancreáticas transformadas pelo oncogene KRAS / Identification of microRNAs regulated by oncogenic KRAS in lung and pancreatic cancer

Mateus Nóbrega Aoki 04 July 2014 (has links)
As neoplasias induzidas pela forma oncogênica da KRAS são doenças muito comuns, para as quais não existem terapias efetivas. Uma inibição direta da KRAS falhou em ensaios clínicos e esforços intensos tem sido feitos para identificar alvos de KRAS importantes para a oncogênese. Uma via promissora regulada por KRAS, que tem sido pouco explora a é a via dos microRNAs (miRNAs). Nossa meta foi identificar miRNAs regulados pela KRAS em células pulmonares e pancreáticas, que possam contribuir para o fenótipo oncogênico. Para alcançar esta meta nós usamos duas abordagens: (1) Nós investigamos o miRNA 486-5p como um alvo de KRAS em câncer de pâncreas e de pulmão. A expressão deste miRNA havia sido correlacionada positivamente com a presença de mutações em KRAS em pacientes portadores de câncer de cólon; (2) Nós usamos uma plataforma de microarranjo para identificar miRNAs diferencialmente expressos entre células humanas primárias imortalizadas pulmonares ou pancreáticas e suas linhagens isogênicas transformadas por KRAS. Na primeira abordagem, conseguimos mostrar que a expressão do miRNA 486-5p está correlacionada ao status de KRAS em células primárias pulmonares, mas não em células primárias pancreáticas. Além disso, geramos células pulmonares tanto com ganho e perda de função de KRAS e demonstramos que KRAS regula a expressão do miRNA 486-5p. Também de terminamos uma correlação negativa entre a expressão de KRAS e a expressão do alvo do miRNA 486-5p FoxO1, um supressor tumoral. Para avaliar como o miRNA 486-5p afeta as propriedades oncogênicas induzidas por KRAS, nós transfectamos oligonucleotídeos inibitórios para o miRNA 486-5p em células pulmonares positivas para mutações em KRAS. A inibição da expressão do miRNA 486-5p levou a uma redução da clonogenicidade e viabilidade celulares. Esta redução não está associada a um aumento de morte celular, mas a uma redução da proliferação celular. Interessantemente, a transfecção de oligonucleotídeos mímicos do miRNA 486-5p em células pulmonares negativas para mutações em KRAS ou em células com perda de função de KRAS por RNAi levou a um aumento da proliferação e clonogenicidade. Estes dados indicam que o miRNA 486-5p, não só é um alvo de KRAS em câncer de pulmão, mas também age como um oncomiR contribuindo para a proliferação celular induzida por KRAS. Na nossa segunda abordagem, nós identificamos 17 miRNAs com expressão aumentada e 3 com expressão diminuída em células primárias pancreáticas expressando KRAS oncogênica. Destes, 9 miRNAs foram foram também identificados por metanálise de dados de microarranjo publicados comparando amostras tumorais pancreáticas com amostras não tumorais. Apesar do experimento de microarranjo com as linhagens primárias pulmonares não ter produzido resultados estatisticamente significativos após a correção por FDR, uma tendência à expressão diferencial foi observada para vários miRNAs e nós validamos por qPCR a expressão diferencial dos miRNAs 720 e 139-3p. Em conclusão, nós conseguimos identificar miRNAs regulados pela KRAS tanto em células pulmonares, quanto pancreáticas. Um melhor entendimento das suas funções biológicas, bem como dos alvos por eles regulados nestes contextos, pode revelar novas vias para a exploração terapêutica. / KRAS-induced lung cancer is a very common disease, for which there are currently no effective therapies. Direct targeting of KRAS has failed in clinical trials and intense efforts are underway to identify KRAS targets that play a crucial role in oncogenesis. One promising KRAS-regulated pathway that has so far been overlooked is the micro RNA (miRNA) pathway. Our goal was to identify miRNAs regulated by oncogenic KRAS in lung and pancreatic cells that could contribute to the oncogenic phenotype. In order to achieve this goal we used two different approaches: (1) We investigated miRNA 486-5p as a KRAS target in lung and pancreatic cancer. The expression of this miRNA had been correlated to the presence of KRAS mutations in colon cancer patients; (2) we used a microarray platform to identify differentially expressed miRNAs between immortalized human primary pulmonary or pancreatic epithelial cell lines and their isogenic K-Ras-transformed counterparts. In our first approach, we were able to show that mi486-5p expression correlates with KRAS status in lung primary cells, but not in pancreatic primary cells. Furthermore, we generated lung cancer cells with either gain-of-function or loss-of-function of KRAS and demonstrated that KRAS regulates miRNA 486-5p in these cells. We also found, in all lung cell models analyzed, a negative correlation between expression of KRAS and expression of miR-486-5p target FoxO1, a tumor suppressor. In order to evaluate how miR-486-5p affects KRAS-induced oncogenic properties, we transfected miR-486-5p inhibitor oligonucleotides into KRAS-positive lung cancer cell lines. Inhibition of miR-486-5p expression leads to reduced clonogenic growth and viability. This reduction is not associated with increased cell death, but with decreased cell proliferation. Interestingly, transfection of miR-486-5p double-stranded RNA mimic oligonucleotides in to KRAS negative lung cancer cell lines or into cells with loss-of-function of KRAS by RNAi leads to enhanced proliferation and clonogenicity. These results indicate, not only that miR-486-5p is a KRAS target in lung cancer, but also that miR-486-5p acts as an oncomiR contributing to KRAS-induced cell proliferation. In our second approach, we identified 17 upregulated microRNAs and 3 downregulated microRNAs in the primary pancreatic cell line expressing KRAS. Of these, 9 miRNAs were also identified by a metanalysis of published microarray datasets comparing pancreatic cancer patient samples to non-cancerous pancreatic tissues. Even though our array experiment in the primary pulmonary cells did not produce statistically significant results after FDR correction, differential expression trends were seen for many miRNAs and we validated miRNAs 720 and 139-3p as differentially expressed. In conclusion we were able to identify miRNAs regulated by KRAS both in lung and pancreatic cancer cells. Further understanding of their biological function, as well as the targets they regulate in these settings, could uncover novel pathways for therapy design.
23

Diversidade e filogenia da ordem Halymeniales (Rhodophyta) no litoral do Brasil / Diversity and phylogeny of the order Halymeniales (Rhodophyta) on the Brazilian Coast

Azevedo, Carolina Angélica Araújo de 02 May 2016 (has links)
As algas da ordem Halymeniales (Rhodophyta) apresentam grande importância ecológica e econômica como produtores primários e de compostos bioativos, além de incluírem espécies invasoras em várias localidades do mundo. A taxonomia do grupo é bastante problemática, com vários registros de identificações equivocadas e mudanças nomenclaturais. Em virtude disso, diversos estudos têm incluído ferramentas moleculares como auxílio à taxonomia morfológica do grupo. O objetivo deste estudo é investigar por meio de técnicas moleculares e morfológicas a diversidade da ordem Halymeniales no litoral do Brasil de forma, a contribuir para o conhecimento da flora marinha do país. Para isso, foram sequenciados três marcadores moleculares, UPA, COI-5P e rbcL, cujos dados, combinados com a observação de caracteres morfológicos, resultaram na delimitação de 26 espécies. Dessas, 11 são espécies novas para a ciência: Corynomorpha cf. clavata, dois táxons morfologicamente identificados como \"Cryptonemia\" crenulata, dois táxons morfologicamente identificados como Cryptonemia seminervis, Halymenia ignifera, Halymenia pinnatifida, Halymenia silviae, Grateloupia cf. dichotoma, Grateloupia cf. filicina 1 e Grateloupia cf. filicina 2. Pelo menos sete gêneros novos foram encontrados, representados pelos táxons: \"Cryptonemia\" bengryi, integrantes do complexo \"Cryptonemia\" crenulata, \"Cryptonemia\" delicatula, \"Halymenia\" elongata, \"Halymenia\" floridana, Halymeniales sp. 1 e Halymeniales sp. 2. Foram encontradas três espécies cuja localidade-tipo é a Ásia: Grateloupia orientalis, Grateloupia turuturu e Grateloupia yangjiangensis. Entre os táxons previamente citados para a costa brasileira, nove não foram encontrados. Se os táxons não encontrados constituírem espécies válidas, a diversidade da ordem no Brasil será de 35 espécies. As análises filogenéticas mostraram que os gêneros Cryptonemia, Halymenia e Grateloupia constituem grupos não-monofiléticos. Os resultados demonstraram a existência de ampla diversidade críptica e pseudo-críptica e de espécies e gêneros novos para a ciência, além de revelarem a ocorrência de espécies não nativas. Este estudo contribui substancialmente para o conhecimento da diversidade de algas marinhas na costa brasileira / Algae of Halymeniales (Rhodophyta) present a wide ecological and economic importance, as primary producers and bioactive compounds producers, and include invasive species worldwide. Its taxonomy is quite problematic, with reports of misidentifications and nomenclatural changes. Therefore, studies have included molecular tools to assist the morphological taxonomy of this order. This study aims to investigate through molecular and morphological techniques the diversity of Halymeniales along the Brazilian coast, in order to contribute to the knowledge of native marine flora. Three molecular markers were sequenced, UPA, COI-5P and rbcL, whose data were allied to morphological characters and resulted in 26 delimited species. There are 11 new species to science: Corynomorpha cf. clavata, two taxa morphologically identified as \"Cryptonemia\" crenulata, two taxa morphologically identified as Cryptonemia seminervis, Halymenia ignifera, Halymenia pinnatifida, Halymenia silviae, Grateloupia cf. dichotoma, Grateloupia cf. filicina 1 and Grateloupia cf. filicina 2. At least seven new genera were found, represented by the following taxa: \"Cryptonemia\" bengryi, representatives of \"Cryptonemia\" crenulata complex, \"Cryptonemia\" delicatula, \"Halymenia\" elongata, \"Halymenia\" floridana, Halymeniales sp. 1 and Halymeniales sp. 2. Three species whose type locality is Asia were detected: Grateloupia orientalis, Grateloupia turuturu and Grateloupia yangjiangensis. Among taxa previously recorded to Brazilian coast, nine were not found. If those taxa constitute valid species, the diversity of the order in Brazil will be represented by 35 species. Phylogenetic analyses showed that Cryptonemia, Halymenia and Grateloupia constitute non-monophyletic groups. Results demonstrated the existence of wide cryptic and pseudo-cryptic diversity as well as novel species and genera, and revealed the presence of non-native species
24

Diversidade de espécies de macroalgas associadas ao Manguezal da Ilha Barnabé, Baixada Santista, SP, Brasil, com base em \"DNA Barcode\" / Diversity of macroalgae species associated with the mangrove of Barnabé Island, Baixada Santista, SP, Brazil, based on \"DNA barcode\"

Sena, Fernando Santos de 08 April 2016 (has links)
Estudos sobre a diversidade de macroalgas de manguezais no Brasil tem-se baseado apenas em abordagens morfológicas, nas quais os caracteres empregados são instáveis e pouco informativos para a identificação e delimitação de espécies. Neste contexto, macroalgas de manguezais foram investigadas pela primeira vez no litoral brasileiro usando uma abordagem molecular, tendo como alvo de estudo o manguezal da Ilha Barnabé, Baixada Santista, São Paulo. Foram utilizados marcadores moleculares do tipo Barcode, UPA e COI-5P, além do rbcL, amplamente empregado para inferências filogenéticas, e o SSU rDNA. Além desses, os marcadores ITS e tufA foram empregados exclusivamente para as algas verdes, este último sem sucesso. Quinze espécies foram registradas para a área estudada, sendo dez Rhodophyta e cinco Chlorophyta. Destas, duas não novas ocorrências para o Estado de São Paulo, Caloglossa apomeiotica e Boodleopsis vaucherioidea. Das quatro espécies do gênero Bostrychia identificadas neste estudo: \"Bostrychia calliptera\", B. montagnei, B. moritziana e B. radicans, apenas B. montagnei revelou-se uma espécie molecular e morfologicamente bem definida. As demais formaram complexos de espécies com linhagens moleculares distintas. Para B. radicans e B. moritziana as análises relevaram três e duas linhagens moleculares, respectivamente, das sete identificadas para o complexo B. radicans/B. moritziana na literatura. O táxon identificado como \"B. calliptera\" mostrou alta divergência molecular com sequências de B. calliptera do Brasil, apresentando morfologia \"B. pinnata\", um táxon atualmente reduzido a sinônimo de B. calliptera. Espécies do gênero Caloglossa, excetuando C. ogasawaraensis, são de difícil identificação morfológica devido aos tênues caracteres considerados de valor diagnóstico e a sua considerável plasticidade fenotípica. Caloglossa apomeiotica, C. confusa e C. leprieurii foram identificadas essencialmente com o emprego de marcadores moleculares. Caloglossa apomeiotica pode ser segregada das demais pela presença de biesporângios, o que impossibilita uma identificação morfológica segura quando coletados talos inférteis, enquanto C. confusa possui nós fortemente contritos. Os dados moleculares obtidos para Catenella caespitosa a partir de sequências de SSU sugerem que as citações dessa espécie para o litoral brasileiro podem estar equivocadas já que apresentam alta divergência intraespecífica com C. caespitosa do banco de dados. A falta de sequências da localidade tipo, de sequências com marcadores do tipo Barcode e de uma maior amostragem molecular das espécies de Catenella nos bancos de dados, nos impossibilitaram chegar a um resultado conclusivo. A obtenção de sequências para as algas verdes foi extremamente problemática, inviabilizando uma comparação mais ampla entres as espécies coletadas. Das duas espécies coletadas de Boodleopsis foram obtidas apenas duas sequências parciais de rbcL para B. vaucherioidea e nenhuma para B. pusilla. A comparação com a única sequência de Boodleopsis depositada nos bancos de dados, uma sequência parcial de rbcL de B. pusilla, revelou baixa divergência molecular com as nossas sequências de B. vaucherioidea. Além da necessidade de obtenção de sequências completas de rbcL de ambas espécies da área estudada para comparação, uma maior amostragem e o emprego de outros marcadores moleculares são necessários para esclarecer o posicionamento taxonômicos desses dois táxons, cuja coespecificidade não pode ser descartada. Morfologicamente, \"Cladophoropsis membranacea\" é uma espécie facilmente identificada, entretanto sequências de ITS obtidas neste estudo são não comparáveis a nenhuma sequência dessa espécie depositada nos bancos de dados, incluindo sequências da localidade tipo. Reconhecidamente Chadophoropsis é um gênero polifilético e integra o complexo Boodlea que inclui diferentes gêneros de Boodleaceae. A obtenção de sequências de outros marcadores como o SSU rDNA e LSU rDNA assim como uma maior amostragem podem ser informativas para esclarecer a posição das \"C. membranacea\" brasileiras dentro das Cladophorales. Mesmo após inúmeras tentativas não foi possível obter sequências para as duas espécies de Rhizoclonium encontradas, R. africanum e R. riparium, cuja identificação foi feita com base em caracteres morfológicos tradicionais / Studies on the diversity of macroalgae from mangroves in Brazil have been based only on morphological approaches, in which characters used are unstable and uninformative for the species identification and delimitation. In this context, macroalgae of mangroves were investigated for the first time in the Brazilian coast using a molecular approach, having as target of our study the mangrove of the Barnabé Island, Santos, São Paulo. DNA Barcode markers UPA and COI-5P were used, besides the rbcL, largely used for phylogenetic inferences, and also SSU rDNA. In addition to these, the ITS and tufA markers were used exclusively for the green algae, the latter unsuccessfully. Fifteen species were recorded for the studied area, ten Rhodophyta and five Chlorophyta. Of these, two are new records for the State of São Paulo, Caloglossa apomeiotica e Boodleopsis vaucherioidea. Of the four species of the genus Bostrychia identified in this study: \"Bostrychia calliptera\", B. montagnei, B. moritziana and B. radicans, only B. montagnei proved to be a molecular and morphologically well-defined species. The other species formed complexes with different molecular lineages. For B. radicans and B. moritziana, the analyses showed three and two molecular lineages, respectively, of the seven identified for the B. radicans/B. moritziana complex in the literature. The taxon identified as \"B. calliptera\" showed high molecular divergence with sequences of B. calliptera from Brazil, presenting morphology \"B. pinnata\", a taxon currently reduced to a synonym of B. calliptera. Caloglossa species, except C. ogasawaraensis, are difficult to identify due to the subtle morphological characters considered of diagnostic value, and their considerable phenotypic plasticity. Caloglossa apomeiotica, C. confusa and C. leprieurii were identified primarily by the use of molecular markers. Caloglossa apomeiotica can be segregated from the others by the presence of bisporangia, which makes unreliable morphological identification when collected infertile thalli, while C. confusa has strongly constricted thallus nodes. The molecular data obtained for Catenella caespitosa from SSU sequences suggest that the citations of this species for the Brazilian coast may be misleading since they have high intraspecific divergence with C. caespitosa from database. Due to the lack of sequences from the type locality, sequences of DNA barcode markers, and a major molecular sampling of Catenella species in databases, became impossible to reach a conclusive result. The obtaining of sequences for green algae was extremely problematic, making impracticable a broader comparison between the collected species. Of the two collected species of Boodleopsis, only two partial sequences of rbcL were obtained for B. vaucherioidea and none for B. pusilla. The comparison with the unique sequence of Boodleopsis deposited in databases, a partial rbcL sequence of B. pusilla, revealed low molecular divergence with our sequences of B. vaucherioidea. Besides the need to obtain complete sequences of rbcL from both species from the studied area for comparison, an increased sampling and the use of other molecular markers are needed to clarify the taxonomic position of these two taxa, whose conspecificity cannot be disregarded. Morphologically, \"Cladophoropsis membranacea\" is an easily identified species, however, ITS sequences obtained in this study are not comparable to any sequence of this species deposited in databases, including sequences from the type locality. Admittedly. Chadophoropsis is a polyphyletic genus and integrates the Boodlea complex that includes different genera of Boodleaceae. The obtaining of sequences from other markers, such as SSU rDNA and LSU rDNA, well as a larger sampling, may be informative to clarify the taxonomic position of \"C. membranacea\" within the Brazilian Cladophorales. Even after numerous attempts we could not get sequences for the two Rhizoclonium species found in the studied area: R. africanum and R. riparium, whose identification was made based on traditional morphological characters
25

Diversidade de espécies de macroalgas associadas ao Manguezal da Ilha Barnabé, Baixada Santista, SP, Brasil, com base em \"DNA Barcode\" / Diversity of macroalgae species associated with the mangrove of Barnabé Island, Baixada Santista, SP, Brazil, based on \"DNA barcode\"

Fernando Santos de Sena 08 April 2016 (has links)
Estudos sobre a diversidade de macroalgas de manguezais no Brasil tem-se baseado apenas em abordagens morfológicas, nas quais os caracteres empregados são instáveis e pouco informativos para a identificação e delimitação de espécies. Neste contexto, macroalgas de manguezais foram investigadas pela primeira vez no litoral brasileiro usando uma abordagem molecular, tendo como alvo de estudo o manguezal da Ilha Barnabé, Baixada Santista, São Paulo. Foram utilizados marcadores moleculares do tipo Barcode, UPA e COI-5P, além do rbcL, amplamente empregado para inferências filogenéticas, e o SSU rDNA. Além desses, os marcadores ITS e tufA foram empregados exclusivamente para as algas verdes, este último sem sucesso. Quinze espécies foram registradas para a área estudada, sendo dez Rhodophyta e cinco Chlorophyta. Destas, duas não novas ocorrências para o Estado de São Paulo, Caloglossa apomeiotica e Boodleopsis vaucherioidea. Das quatro espécies do gênero Bostrychia identificadas neste estudo: \"Bostrychia calliptera\", B. montagnei, B. moritziana e B. radicans, apenas B. montagnei revelou-se uma espécie molecular e morfologicamente bem definida. As demais formaram complexos de espécies com linhagens moleculares distintas. Para B. radicans e B. moritziana as análises relevaram três e duas linhagens moleculares, respectivamente, das sete identificadas para o complexo B. radicans/B. moritziana na literatura. O táxon identificado como \"B. calliptera\" mostrou alta divergência molecular com sequências de B. calliptera do Brasil, apresentando morfologia \"B. pinnata\", um táxon atualmente reduzido a sinônimo de B. calliptera. Espécies do gênero Caloglossa, excetuando C. ogasawaraensis, são de difícil identificação morfológica devido aos tênues caracteres considerados de valor diagnóstico e a sua considerável plasticidade fenotípica. Caloglossa apomeiotica, C. confusa e C. leprieurii foram identificadas essencialmente com o emprego de marcadores moleculares. Caloglossa apomeiotica pode ser segregada das demais pela presença de biesporângios, o que impossibilita uma identificação morfológica segura quando coletados talos inférteis, enquanto C. confusa possui nós fortemente contritos. Os dados moleculares obtidos para Catenella caespitosa a partir de sequências de SSU sugerem que as citações dessa espécie para o litoral brasileiro podem estar equivocadas já que apresentam alta divergência intraespecífica com C. caespitosa do banco de dados. A falta de sequências da localidade tipo, de sequências com marcadores do tipo Barcode e de uma maior amostragem molecular das espécies de Catenella nos bancos de dados, nos impossibilitaram chegar a um resultado conclusivo. A obtenção de sequências para as algas verdes foi extremamente problemática, inviabilizando uma comparação mais ampla entres as espécies coletadas. Das duas espécies coletadas de Boodleopsis foram obtidas apenas duas sequências parciais de rbcL para B. vaucherioidea e nenhuma para B. pusilla. A comparação com a única sequência de Boodleopsis depositada nos bancos de dados, uma sequência parcial de rbcL de B. pusilla, revelou baixa divergência molecular com as nossas sequências de B. vaucherioidea. Além da necessidade de obtenção de sequências completas de rbcL de ambas espécies da área estudada para comparação, uma maior amostragem e o emprego de outros marcadores moleculares são necessários para esclarecer o posicionamento taxonômicos desses dois táxons, cuja coespecificidade não pode ser descartada. Morfologicamente, \"Cladophoropsis membranacea\" é uma espécie facilmente identificada, entretanto sequências de ITS obtidas neste estudo são não comparáveis a nenhuma sequência dessa espécie depositada nos bancos de dados, incluindo sequências da localidade tipo. Reconhecidamente Chadophoropsis é um gênero polifilético e integra o complexo Boodlea que inclui diferentes gêneros de Boodleaceae. A obtenção de sequências de outros marcadores como o SSU rDNA e LSU rDNA assim como uma maior amostragem podem ser informativas para esclarecer a posição das \"C. membranacea\" brasileiras dentro das Cladophorales. Mesmo após inúmeras tentativas não foi possível obter sequências para as duas espécies de Rhizoclonium encontradas, R. africanum e R. riparium, cuja identificação foi feita com base em caracteres morfológicos tradicionais / Studies on the diversity of macroalgae from mangroves in Brazil have been based only on morphological approaches, in which characters used are unstable and uninformative for the species identification and delimitation. In this context, macroalgae of mangroves were investigated for the first time in the Brazilian coast using a molecular approach, having as target of our study the mangrove of the Barnabé Island, Santos, São Paulo. DNA Barcode markers UPA and COI-5P were used, besides the rbcL, largely used for phylogenetic inferences, and also SSU rDNA. In addition to these, the ITS and tufA markers were used exclusively for the green algae, the latter unsuccessfully. Fifteen species were recorded for the studied area, ten Rhodophyta and five Chlorophyta. Of these, two are new records for the State of São Paulo, Caloglossa apomeiotica e Boodleopsis vaucherioidea. Of the four species of the genus Bostrychia identified in this study: \"Bostrychia calliptera\", B. montagnei, B. moritziana and B. radicans, only B. montagnei proved to be a molecular and morphologically well-defined species. The other species formed complexes with different molecular lineages. For B. radicans and B. moritziana, the analyses showed three and two molecular lineages, respectively, of the seven identified for the B. radicans/B. moritziana complex in the literature. The taxon identified as \"B. calliptera\" showed high molecular divergence with sequences of B. calliptera from Brazil, presenting morphology \"B. pinnata\", a taxon currently reduced to a synonym of B. calliptera. Caloglossa species, except C. ogasawaraensis, are difficult to identify due to the subtle morphological characters considered of diagnostic value, and their considerable phenotypic plasticity. Caloglossa apomeiotica, C. confusa and C. leprieurii were identified primarily by the use of molecular markers. Caloglossa apomeiotica can be segregated from the others by the presence of bisporangia, which makes unreliable morphological identification when collected infertile thalli, while C. confusa has strongly constricted thallus nodes. The molecular data obtained for Catenella caespitosa from SSU sequences suggest that the citations of this species for the Brazilian coast may be misleading since they have high intraspecific divergence with C. caespitosa from database. Due to the lack of sequences from the type locality, sequences of DNA barcode markers, and a major molecular sampling of Catenella species in databases, became impossible to reach a conclusive result. The obtaining of sequences for green algae was extremely problematic, making impracticable a broader comparison between the collected species. Of the two collected species of Boodleopsis, only two partial sequences of rbcL were obtained for B. vaucherioidea and none for B. pusilla. The comparison with the unique sequence of Boodleopsis deposited in databases, a partial rbcL sequence of B. pusilla, revealed low molecular divergence with our sequences of B. vaucherioidea. Besides the need to obtain complete sequences of rbcL from both species from the studied area for comparison, an increased sampling and the use of other molecular markers are needed to clarify the taxonomic position of these two taxa, whose conspecificity cannot be disregarded. Morphologically, \"Cladophoropsis membranacea\" is an easily identified species, however, ITS sequences obtained in this study are not comparable to any sequence of this species deposited in databases, including sequences from the type locality. Admittedly. Chadophoropsis is a polyphyletic genus and integrates the Boodlea complex that includes different genera of Boodleaceae. The obtaining of sequences from other markers, such as SSU rDNA and LSU rDNA, well as a larger sampling, may be informative to clarify the taxonomic position of \"C. membranacea\" within the Brazilian Cladophorales. Even after numerous attempts we could not get sequences for the two Rhizoclonium species found in the studied area: R. africanum and R. riparium, whose identification was made based on traditional morphological characters
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Diversidade e filogenia da ordem Halymeniales (Rhodophyta) no litoral do Brasil / Diversity and phylogeny of the order Halymeniales (Rhodophyta) on the Brazilian Coast

Carolina Angélica Araújo de Azevedo 02 May 2016 (has links)
As algas da ordem Halymeniales (Rhodophyta) apresentam grande importância ecológica e econômica como produtores primários e de compostos bioativos, além de incluírem espécies invasoras em várias localidades do mundo. A taxonomia do grupo é bastante problemática, com vários registros de identificações equivocadas e mudanças nomenclaturais. Em virtude disso, diversos estudos têm incluído ferramentas moleculares como auxílio à taxonomia morfológica do grupo. O objetivo deste estudo é investigar por meio de técnicas moleculares e morfológicas a diversidade da ordem Halymeniales no litoral do Brasil de forma, a contribuir para o conhecimento da flora marinha do país. Para isso, foram sequenciados três marcadores moleculares, UPA, COI-5P e rbcL, cujos dados, combinados com a observação de caracteres morfológicos, resultaram na delimitação de 26 espécies. Dessas, 11 são espécies novas para a ciência: Corynomorpha cf. clavata, dois táxons morfologicamente identificados como \"Cryptonemia\" crenulata, dois táxons morfologicamente identificados como Cryptonemia seminervis, Halymenia ignifera, Halymenia pinnatifida, Halymenia silviae, Grateloupia cf. dichotoma, Grateloupia cf. filicina 1 e Grateloupia cf. filicina 2. Pelo menos sete gêneros novos foram encontrados, representados pelos táxons: \"Cryptonemia\" bengryi, integrantes do complexo \"Cryptonemia\" crenulata, \"Cryptonemia\" delicatula, \"Halymenia\" elongata, \"Halymenia\" floridana, Halymeniales sp. 1 e Halymeniales sp. 2. Foram encontradas três espécies cuja localidade-tipo é a Ásia: Grateloupia orientalis, Grateloupia turuturu e Grateloupia yangjiangensis. Entre os táxons previamente citados para a costa brasileira, nove não foram encontrados. Se os táxons não encontrados constituírem espécies válidas, a diversidade da ordem no Brasil será de 35 espécies. As análises filogenéticas mostraram que os gêneros Cryptonemia, Halymenia e Grateloupia constituem grupos não-monofiléticos. Os resultados demonstraram a existência de ampla diversidade críptica e pseudo-críptica e de espécies e gêneros novos para a ciência, além de revelarem a ocorrência de espécies não nativas. Este estudo contribui substancialmente para o conhecimento da diversidade de algas marinhas na costa brasileira / Algae of Halymeniales (Rhodophyta) present a wide ecological and economic importance, as primary producers and bioactive compounds producers, and include invasive species worldwide. Its taxonomy is quite problematic, with reports of misidentifications and nomenclatural changes. Therefore, studies have included molecular tools to assist the morphological taxonomy of this order. This study aims to investigate through molecular and morphological techniques the diversity of Halymeniales along the Brazilian coast, in order to contribute to the knowledge of native marine flora. Three molecular markers were sequenced, UPA, COI-5P and rbcL, whose data were allied to morphological characters and resulted in 26 delimited species. There are 11 new species to science: Corynomorpha cf. clavata, two taxa morphologically identified as \"Cryptonemia\" crenulata, two taxa morphologically identified as Cryptonemia seminervis, Halymenia ignifera, Halymenia pinnatifida, Halymenia silviae, Grateloupia cf. dichotoma, Grateloupia cf. filicina 1 and Grateloupia cf. filicina 2. At least seven new genera were found, represented by the following taxa: \"Cryptonemia\" bengryi, representatives of \"Cryptonemia\" crenulata complex, \"Cryptonemia\" delicatula, \"Halymenia\" elongata, \"Halymenia\" floridana, Halymeniales sp. 1 and Halymeniales sp. 2. Three species whose type locality is Asia were detected: Grateloupia orientalis, Grateloupia turuturu and Grateloupia yangjiangensis. Among taxa previously recorded to Brazilian coast, nine were not found. If those taxa constitute valid species, the diversity of the order in Brazil will be represented by 35 species. Phylogenetic analyses showed that Cryptonemia, Halymenia and Grateloupia constitute non-monophyletic groups. Results demonstrated the existence of wide cryptic and pseudo-cryptic diversity as well as novel species and genera, and revealed the presence of non-native species
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影響銀行不動產擔保品估值調整幅度因素之研究-以S銀行為例 / The Determinants Affecting the Adjustment of Appraised Value of Real Estate Collateral--- A Study of S Bank

陳穎貞, Chen, Ying Chen Unknown Date (has links)
過去文獻對於不動產擔保品估值的研究,通常以銀行最終核定之價格做實證分析,本研究從銀行內部不動產擔保品價格變動情形,來探討影響銀行辦理授信程序時內部各單位決定不動產擔保品價值之因素,就不動產擔保品估值為依變數,實證分析申請人與不動產擔保品各項條件,研究結果顯示分行內部承辦人員估值及總行授審處估值之各項變數中以申請額度、區位、建物面積、屋齡、車位之有無等五項變數對估值具顯著影響。總行鑑價科則在區位、建物面積、屋齡、車位之有無等四項變數呈現顯著,影響總行授審處估值與鑑價科估值差額之因素則以是否為年齡、六個月平均存款餘額及申請額度等變數呈現顯著。分析結果顯示,分行承接業務時,考量擔保品條件與申貸金額。鑑價科則可能因此受到分行內部承辦人員估值的錨點影響,產生干擾效果。而授審處調整擔保品估值金額時,考量還款能力時,可能更重視的是借款戶於本行的往來存款實績。 / Previous studies on the appraised values of real estate collaterals are mostly empirical analyses on the final value approved by the creditor bank. The study, directing its attention to the changes in the appraised value of real estate collateral within a bank, examined the factor affecting the value of real estate collateral appraised by the different units of a bank. With the appraised value set as the dependent variable, the study conducted an empirical analysis on the loan applicants and the various features of the pledged collaterals. According to the study results, loan amount, location of the pledged collateral, floor area, age of the building, and provision of parking space emerged to be variables reaching statistical significance in the appraisal at both a local branch and the head office. Location, floor area, age, and parking space remained the statistically significant variable for the head office. Age of the applicant, average deposit account balance for the past six months, and loan amount appeared to be the statistically significant variable influencing the discrepancy in the values appraised by the local branch and the head office. As indicated by the analysis results, the local branch tended to place greater emphasis on the features of the pledged collateral and the loan amount; the appraisal office at the local branch might therefore be interfered by the value assessed by the responsible appraiser due to the anchoring effect. On the other hand, in adjusting the value appraised by the local branch, the head office would pay considerable attention to the applicant’s overall performance as a bank client in addition to repayment capacity.
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Identification of micro-RNAs and their messenger RNA targets in Prostate cancer and Biological fluids

Sharma, Kanika 01 January 2014 (has links)
Prostate cancer is the second most common cancer in the United States that affects men today. To better treat this disease accurate biomarkers and successful therapeutic treatments are needed. A novel approach to understand the mechanisms behind prostate cancer tumor formation lies in identifying dysregulated micro-RNAs (miRNAs), which are a class of small (18-24 nucleotides) non-coding RNAs that regulate gene expression posttranscriptionally by either inhibiting protein synthesis or signaling messenger-RNA for degradation. Multiple miRNAs were discovered in our highly tumorigenic and metastatic prostate cancer progression model M12 cell line compared to its weakly tumorigenic P69 parental cell line. Various analyses such as human panel analyses, single-miR analyses and patient tumor biopsy samples were analyzed to determine dysregulated miRNAs that contributed to the progression and metastasis of prostate cancer. Together with performing experiments to identify miRNAs, a de novo next generation sequencing approach was applied to identify miRNAs naturally present in biological fluids of normal and healthy subjects. Since, these miRNAs are highly dysregulated in many diseases, including cancer, they can act as potential biomarkers or therapeutic targets to improve treatments for prostate cancer. Essential miRNAs studied for this research were miR-17-3p that is known to target the ErbB2 mRNA; miR-299-5p that directly targets osteopontin (OPN) mRNA, and miR-147b that directly targets many mRNAs, such as COL4A2, ALDH5A1, NDUFA4, SDHD, and IER5. A wide range of miRNAs were identified in six biological fluids: venous blood, menstrual blood, vaginal fluid, semen, saliva, and feces. There were some miRNAs that were common to all 6 body fluids, some unique to each body fluid, and some miRNAs that literature suggested could potentially be biomarkers or normalizers for body fluid characterization.
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Species identification and discovery in common marine macroalgae: Fucus, Porphyra and Ulva using a DNA barcoding approach.

Hana, Kucera January 2010 (has links)
The oceans represent a wealth of biological diversity where many species remain to be discovered and described. Among seaweeds, a paucity of morphological features by which to differentiate species means that many genera harbour overlooked or cryptic species. Fucus, Porphyra and Ulva are three common genera of marine intertidal algae and all include species that are particularly difficult to distinguish morphologically. DNA barcoding has been championed as a revolutionary tool for species identification and discovery and applying this tool to algae was a logical step due to the difficulty of morphological identification of many algal species. This thesis is part of a significant initiative aimed at identification and discovery of all species of seaweeds in Canadian waters, using a DNA barcoding approach. The original concept of DNA barcoding relied on comparing the 5’ region of the mitochondrial cytochrome c oxidase 1 (COI-5P) gene among animal species. In this study, DNA barcoding with COI-5P was applied to the brown algal genus Fucus and worked as well as any other marker to assign morphologies to known species. The DNA barcoding results also uncovered substantial phenotypic diversity in Pacific F. distichus. Results were confirmed by comparison with sequences of the nuclear internal transcribed spacer region (ITS). For Porphyra, COI-5P DNA barcoding was compared with species identification using the chloroplast large rubisco subunit (rbcL) and the Universal Plastid Amplicon (UPA) in a floristic survey of Canadian Porphyra species. Two new species were discovered and described (Porphyra corallicola and Porphyra peggicovensis), and P. cuneiformis was synonymized with P. amplissima. The COI-5P emerged as the best marker for species discrimination despite difficulties with primer universality. To aid in choosing a marker for DNA barcoding for green algae, the universality and species discriminatory power of the rubisco large subunit (rbcL) (considering the 5’ and 3’ fragments independently), the UPA, the D2/D3 region of the nuclear large ribosomal subunit (LSU-D2/D3) and the ITS were evaluated. While the rbcL-3P highlighted several cryptic species, and worked well to distinguish Ulva species, more research is needed to recommend a marker for DNA barcoding generally in marine green macroalgae.
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Zhodnocení efektivity sociálně preventivního programu Pět P v České republice a jeho vývoj / Effectivity evaluation of social-preventive program 5P in the Czech republic and its development

BŘÍZOVÁ, Bohdana January 2010 (has links)
The theoretical outcomes of the mentoring program BBBS and subsequently also the solutions of the program 5 P in the Czech Republic are introduced in the theoretical part of the dissertation work. Furthermore the author summarizes the principles of the program and explains the management of the work with the volunteers. She also focuses on the relationship between a child and a volunteer, its typology and its development. The last but not the least the author addresses the evaluation method for BBBS/5 P which is called the Program Based Outcome Evaluation (POE). Furthermore the author fulfills the four selected goals in the research part of the work. The first goal is focused on the modification of the original evaluation method POE and its adaptation for the Czech socio-cultural circumstances. The second goal is the analyses of the current state of the realization of the program 5 P in the Czech Republic with the focus on the registration of the program as the social service. The third very important goal is to evaluate the general trends of the effectiveness of the program by the means of the statistical analysis of the results of the evaluation method POE. The last goal is the development of the new or the adaptation of the current specialized and methodological materials for 5 P.

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