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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.
11

Étude génomique et fonctionnelle de la dérégulation du gène HMGA2 dans les tumeurs adipocytaires / Genomic and functional study of HMGA2 deregulation in adipocytic tumors

Saada-Bouzid, Esma 05 February 2015 (has links)
Les tumeurs adipocytaires (TA) bénignes sont majoritairement constituées par les lipomes, alors que les TA malignes sont principalement des Tumeurs Lipomateuses Atypiques (TLA)/ liposarcome (LPS) bien différenciés (LBD) et les LPS dédifférenciés (LDD). Le gène HMGA2 (High Mobility Group A2) est remanié dans certains lipomes et amplifié dans les TLA/LBD et LDD. Ainsi, nous avons émis l’hypothèse que HMGA2 jouait un rôle fondamental dans la genèse des TA bénignes et malignes. En faveur de cette hypothèse, nous avons observé une surexpression constante de HMGA2 dans les TLA/LBD et LDD avec amplification de HMGA2 et les lipomes avec remaniement de HMGA2. Dans un cas de lipomatose, hypertrophie pathologique du tissu adipeux sans anomalie du gène HMGA2, une surexpression de HMGA2 était associée à une inhibition de l’expression de plusieurs microARN let-7. En revanche, nos travaux ne sont pas en faveur d’un rôle prépondérant des microARN let7 dans la surexpression de HMGA2 dans les TA. Nous nous sommes également intéressés aux gènes partenaires de fusion avec HMGA2 dans les lipomes et avons notamment identifié une nouvelle fusion impliquant PPAP2B (Phosphatidic Acid Phosphatase type 2B) localisé en 1p32. Nous avons aussi confirmé le rôle du gène NFIB (9p22) dans les lipomes. Enfin, nous avons établi des corrélations pronostiques dans une grande série de 116 TLA/LBD et LDD : l’amplification de HMGA2 était associée à l’histotype TLA/LBD et à une survie longue alors que les amplifications de CDK4 et JUN sont associées au type LDD et une survie courte. Ainsi, nos données confortent l’hypothèse d’un rôle précoce et majeur de HMGA2 dans la genèse des TA bien différenciées. / Benign adipocytic tumors (AT) are mainly represented by lipomas whereas most malignant AT are Atypical Lipomatous Tumors/Well-differentiated liposarcomas (ALT/WDLPS) and dedifferentiated liposarcomas (DDLPS). HMGA2 gene (High Mobility Group A2) is rearranged in some lipomas and amplified in ALT/WDLPS and DDLPS. Thus, we hypothesized that HMGA2 played a fundamental role in benign and malignant AT genesis. In favor of this hypothesis, we observed a constant overexpression of HMGA2 in amplified ALT/WDLPS and DDLPS, and in rearranged lipomas. In a case of lipomatosis, that is a pathological proliferation of the adipocytic tissu without rearrrangement of HMGA2, the overexpression of HMGA2 was asssociated with an inhibition of the expression of several let-7 microRNAs. However, we did not find a leading role of let-7 microRNAs in the deregulation of HMGA2 expression in AT. We also studied partner fusion genes of HMGA2 in lipomas and have specifically identified a new fusion involving PPAP2B (Phosphatidic Acid Phosphatase type 2B) which is located in 1p32. We also confirmed the role of NFIB gene (9p22) in lipomas. Finally, we have established prognostic correlations in a series of 116 ALT/WDLPS and DDLPS: HMGA2 amplification was associated with ALT/WDLPS histotype and a longer survival whereas respective CDK4 and JUN amplification were associated with DDLPS and shorter survival. Thus, our data support the hypothesis of an early and major role of HMGA2 in the genesis well differentiated AT.
12

Citogenética comparativa de peixes da família Cichlidae /

Poletto, Andréia Benedita. January 2009 (has links)
Orientador: Cesar Martins / Banca: Eliana Feldberg / Banca: André laforga Vanzela / Banca: Lígia Souza Lima Silveira da Mota / Banca: Marcelo Ricardo Vicari / Resumo: Este trabalho teve por objetivo analisar citogeneticamente espécies da família Cichlidae de diferentes origens. Foram feitas análises de uma espécie asiática, de 22 africanas e 30 neotropicais. O número diplóide na família variou de 2n=40 a 2n=60. Os sítios de genes de RNAr 18S variaram de 2 a 9 cromossomos portadores, com sítios terminais para os africanos e em apenas um grande par cromossômico em posição intersticial ou terminal para a maioria dos neotropicais. A hibridação do gene RNAr 5S marcou sítios múltiplos em regiões intersticiais e centroméricas em duas espécies africanas, enquanto que nos ciclídeos neotropicais marcou de um a dois pares, sempre em posição intersticial. Em Haplocromis obliquidens foram encontrados um a dois grandes cromossomos metacêntricos supernumerários e heterocromáticos em 39,6% da população, tanto em fêmea quanto em macho. Este cromossomo B apresentou sítios múltiplos de hibridação de DNAr 18S e sinais leves na região centromérica do DNA satélite centromérico SATA. Sequências repetitivas inseridas em BACs hibridaram de forma difusa por toda a extensão do elemento supernumerário. Esse cromossomo B pode ter se originado a partir de um isocromossomo, ou por acúmulo de DNA repetitivo num pequeno proto-cromossomo B. Em Metriaclima lombardoi um grande cromossomo B metacêntricoe heterocromático foi detectado em 50% das fêmeas e em nenhum macho. Este elemento não apresentou sinais de hibridação de DNAr 18S, porém DNAs repetitivos inseridos em BACs hibridaram nos braços menores do primeiro par do complemento A, fortemente na região centromérica, e de forma difusa ao longo do cromossomo B. Hipotetizamos que este cromossomo B pode ter se originado a partir de um fragmento do primeiro par do complemento A, tendo acumulado DNAs repetitivos como consequência da ausência de recombinação. Sugerimos também que a origem... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work had the aim of cytogenetic analyses of Cichlidae species from diverse origin. It was analyzed one asian, 22 african and 30 neotropical species. The diploid number ranged between 2n=40 and 2n=60 chromosomes. The 18S rRNA gene sites varied from two to nine bearer chromosomes, in terminal position for the africans ones, and just in one large chromosome pair, in interstitial or terminal position, for the majority of the neotropical ones. The hybridization with 5S rRNA genes labeled multiple sites in two African species, in centromeric and interstitial position, whereas in the Neotropical cichlids it labeled interstitially in one to two pairs of chromosomes. In Haplochromis obliquidens it was found one or two metacentric supernumerary heterochromatic chromosome(s) in 39,6% of the population including males as well as females. This B chromosome showed multiple hybridization sites of 18S rDNA and the SATA centrometromeric satellite DNA slightly labeled in the cetromeric region, while BAC-clone enriched of repeated sequences hybridized scattered along the B chromosome. This B chromosome could have originated from an isochromosome or by accumulation of repetitive DNA in a small proto-B chromosome. In Metriaclima lombardoi a large heterochromatic metacentric B chromosome was detected in 50% of females and none males. This element did not show signals of hybridization of 18S rDNA but BAC-clone enriched of repeated DNAs hybridized in the small arms of first pair of complement, strongly in the centromeric region, and scattered along the B chromosome. We hypothesized that this B chromosome could have originated from a fragment of the A complement, and had acumulated repetitive DNAs as consequence of absence of recombination. We also suggest that the origin of this B from the first chromosome pair could be driving the bearer individuals to present female characteristics independently... (Complete abstract click electronic access below) / Doutor
13

Citogenética de populações de Piabina argentea(Teleostei, Characiformes, Characidae) das bacias dos rios Paranapanema e Tietê /

Pazian, Marlon Felix. January 2008 (has links)
Orientador: Fausto Foresti / Banca: Cristiane Kioko Shimabukuro Dias / Banca: Orlando Moreira Filho / Resumo: Foi realizada a análise citogenética de duas espécies do Gênero Piabina, P. anhembi e P. argentea, utilzando-se técnicas de coloração cromossômica convencional com Giemsa, localização das Ag-RONs, coloração com CMA3, hibridação in situ com as sondas de DNAr 18S e 5S e bandamento C. Todas as quatro amostras de P. argentea apresentaram 2n=52 cromossomos e números fundamentais diferentes, com exceção de duas amostras populacionais coletadas na bacia do rio Paranapanema. Três apresentaram Ag-RONs múltiplas (Avaré, Botucatu e Bauru) e a amostra da população coletada na localidade Itatinga apresentou Ag- RONs simples e um polimorfismo de tamanho das mesmas. A hibridação in situ com o uso de sondas de DNAr 5S mostrou diferenças entre as amostras das populações. O bandamento C marcou em sua maioria as regiões terminais e centroméricas dos cromossomos. As análises evidenciaram a existência de diferenças citogenéticas entre as amostras de P. argentea coletadas, sugerindo a existência de diferenciação populacional. As diferenças citogenéticas encontradas podem ocorrer devido ao fato de que P. argentea habite apenas riachos, o que poderia levar ao isolamento destas populações. Também foi analisada a amostra de uma população de P. anhembi coletada no município de Salesópolis, que também apresentou 2n=52 cromossomos, Ag-RONs simples e polimorfismos de tamanho das Ag-RONs. A hibridação in situ com a utilização da sonda de DNAr 18S mostrou três cromossomos marcados e com a sonda de DNAr 5S mostrou dois cromossomos marcados. O Bandamento C mostrou bandas nas regiões pericentromérica de dois pares cromossômicos nos exemplares desta espécie. Considerando-se o fato deste grupo habitar geralmente regiões específicas dos ambientes de cabeceira dos riachos, isto pode constituir um fator... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Two species of the genus Piabina have been analyzed, P. argentea and P. anhembi using cytogenetic techniques (Staining of Giemsa, staining of Ag-NORs, fluorescent staining CMA3, hybridization in situ using probe of rDNA 18S and 5S and C-band). All samples of P. argentea presented 2n=52 chromosome and different fundamental numbers, with exception of the individuals of two population collected in the Paranapanema river basin. Three samples analyzed from Avaré, Botucatu and Bauru presented multiple NORs and individuals from Itatinga presented the single NOR and the polymorphic NOR. The in situ hybridization technique using the DNAr 5S probe showed differences between samples of all the populations. The technique C-banding showed marks in most of terminals and centromeric regions of the chromosomes. The existence of cytogenetic differences between the individuals of different samples collected of P. argentea, suggests a possible population differentiation. The occurrence of cytogenetic differences happened by the fact that P. argentea live only in upper stream rivers, and this can determine a process of population isolation. A sample of P.anhembi collected in the Salesópolis city was also analyzed and presented 2n=52 chromosomes, simple Ag-NORs and polymorphism of the NORs. The use of in situ hybridization technique with DNAr 18S probe revealed three labellad chromosomes, and with the rDNA 5S probe showed two labellad chromosomes. The technique of C-banding revealed the presence of heterochromatin in the pericentromeric regions of two chromosome pairs. The species Piabina argentea most of the time live in a specific environment in upper stream rivers. This possible isolation can fix spot modifications in the chromosome if it occurs. However this fact don't change the macro structure of the chromosome in different generations. / Mestre
14

Citogenética de populações de Piabina argentea(Teleostei, Characiformes, Characidae) das bacias dos rios Paranapanema e Tietê

Pazian, Marlon Felix [UNESP] 30 September 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-30Bitstream added on 2014-06-13T20:00:08Z : No. of bitstreams: 1 pazian_mf_me_botib.pdf: 586728 bytes, checksum: ee9c1b3e254811f66a8a7cf904e2114b (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Foi realizada a análise citogenética de duas espécies do Gênero Piabina, P. anhembi e P. argentea, utilzando-se técnicas de coloração cromossômica convencional com Giemsa, localização das Ag-RONs, coloração com CMA3, hibridação in situ com as sondas de DNAr 18S e 5S e bandamento C. Todas as quatro amostras de P. argentea apresentaram 2n=52 cromossomos e números fundamentais diferentes, com exceção de duas amostras populacionais coletadas na bacia do rio Paranapanema. Três apresentaram Ag-RONs múltiplas (Avaré, Botucatu e Bauru) e a amostra da população coletada na localidade Itatinga apresentou Ag- RONs simples e um polimorfismo de tamanho das mesmas. A hibridação in situ com o uso de sondas de DNAr 5S mostrou diferenças entre as amostras das populações. O bandamento C marcou em sua maioria as regiões terminais e centroméricas dos cromossomos. As análises evidenciaram a existência de diferenças citogenéticas entre as amostras de P. argentea coletadas, sugerindo a existência de diferenciação populacional. As diferenças citogenéticas encontradas podem ocorrer devido ao fato de que P. argentea habite apenas riachos, o que poderia levar ao isolamento destas populações. Também foi analisada a amostra de uma população de P. anhembi coletada no município de Salesópolis, que também apresentou 2n=52 cromossomos, Ag-RONs simples e polimorfismos de tamanho das Ag-RONs. A hibridação in situ com a utilização da sonda de DNAr 18S mostrou três cromossomos marcados e com a sonda de DNAr 5S mostrou dois cromossomos marcados. O Bandamento C mostrou bandas nas regiões pericentromérica de dois pares cromossômicos nos exemplares desta espécie. Considerando-se o fato deste grupo habitar geralmente regiões específicas dos ambientes de cabeceira dos riachos, isto pode constituir um fator... / Two species of the genus Piabina have been analyzed, P. argentea and P. anhembi using cytogenetic techniques (Staining of Giemsa, staining of Ag-NORs, fluorescent staining CMA3, hybridization in situ using probe of rDNA 18S and 5S and C-band). All samples of P. argentea presented 2n=52 chromosome and different fundamental numbers, with exception of the individuals of two population collected in the Paranapanema river basin. Three samples analyzed from Avaré, Botucatu and Bauru presented multiple NORs and individuals from Itatinga presented the single NOR and the polymorphic NOR. The in situ hybridization technique using the DNAr 5S probe showed differences between samples of all the populations. The technique C-banding showed marks in most of terminals and centromeric regions of the chromosomes. The existence of cytogenetic differences between the individuals of different samples collected of P. argentea, suggests a possible population differentiation. The occurrence of cytogenetic differences happened by the fact that P. argentea live only in upper stream rivers, and this can determine a process of population isolation. A sample of P.anhembi collected in the Salesópolis city was also analyzed and presented 2n=52 chromosomes, simple Ag-NORs and polymorphism of the NORs. The use of in situ hybridization technique with DNAr 18S probe revealed three labellad chromosomes, and with the rDNA 5S probe showed two labellad chromosomes. The technique of C-banding revealed the presence of heterochromatin in the pericentromeric regions of two chromosome pairs. The species Piabina argentea most of the time live in a specific environment in upper stream rivers. This possible isolation can fix spot modifications in the chromosome if it occurs. However this fact don`t change the macro structure of the chromosome in different generations.
15

Caracterização citogenética de genótipos de Heliconia L. (Heliconiaceae)

COSTA, Marília Gabriela de Santana 29 July 2013 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-09-19T14:46:16Z No. of bitstreams: 1 Marilia Gabriela de Santana Costa.pdf: 1426412 bytes, checksum: c3c7baa96284c5f7b4c52bec2911ec26 (MD5) / Made available in DSpace on 2016-09-19T14:46:16Z (GMT). No. of bitstreams: 1 Marilia Gabriela de Santana Costa.pdf: 1426412 bytes, checksum: c3c7baa96284c5f7b4c52bec2911ec26 (MD5) Previous issue date: 2013-07-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Helinonia L. (family Heliconiaceae) comprises about 207 species, mostly of Neotropical origin, with elevated ornamental interest. Their identification is performed with difficulty and several species are recognized as synonyms. This study aimed to characterize cytogenetically 10 genotypes of Heliconia, using fluorochrome staining with DAPI and CMA and FISH with rDNA 45S and 5S probes. The karyotypes were symmetric, with 2n = 2x = 24 chromosomes for diploid species, with average length ranging from 0.88 to 3.35 μm. In relation to CMA/DAPI staining and FISH, CMA+/DAPI0/rDNA 5S proximal sites were observed in two and three small chromosomes in diploid and triploid genotypes, respectively. For CMA++/DAPI-/rDNA 45S sites, two or four sites per genotype were observed. For H. psittacorum diploid populations, two subterminal sites with distended satellite were found, and, for H. spathocircinata, four terminal sites without satellite were found. Heliconia psittacorum x H. spathocircinata hybrids (‘Golden Torch Adrian’ e ‘Golden Torch’), as expected, showed three labeled chromosomes, two similar to H. spathocircinata and one to H. psittacorum. For 'Suriname Sassy' and 'Sassy', three terminal sites with satellite similar to diploid H. psittacorum were observed. Heliconia bihai had two chromosomes with proximal sites. Similarly, H. caribaea x H. bihai cv. Jacquinii hybrid showed two proximal sites CMA++/DAPI-/DNAr 45S, but with size and morphology chromosome heteromorphism. The distribution of 5S and 45S rDNA sites, both CMA positive, corroborated the triploid origin for 'Sassy Suriname' and 'Sassy' genotypes from diploid genotypes H. psittacorum as well as the hybrids H. psittacorum x H. spathocircinata ('Golden Torch' and 'Golden Torch Adrian') and H. caribaea x H. bihai cv. Jacquinii from their respective parents. / O gênero Heliconia L. (família Heliconiaceae) possui cerca de 207 espécies, principalmente de origem neotropical, com elevado interesse ornamental. Sua identificação é realizada com dificuldade e diversas espécies são reconhecidas como sinonímias. O presente trabalho teve por objetivo a caracterização citogenética de 10 genótipos de Heliconia mediante as técnicas de coloração com fluorocromos CMA e DAPI e FISH para sítios de DNAr 45S e 5S. Os cariótipos foram simétricos, com número cromossômico para as espécies diploides de 2n = 2x = 24 e comprimento médio dos cromossomos de 0,88 a 3,35 μm. Em relação à coloração CMA/DAPI e FISH, observou-se marcação proximal CMA+/DAPI0/DNAr 5S em dois e três cromossomos pequenos, nos genótipos diploides e triploides, respectivamente. Para as marcações CMA++/DAPI-/DNAr 45S, por sua vez, observou-se de dois a quatro sítios por genótipo. Nas populações diploides de H. psittacorum observados dois cromossomos com marcação subterminal e satélite distendido e para H. spathocircinata foram encontrados quatro cromossomos com marcação terminal e ausência de satélite. Os híbridos de H. psittacorum x H. spathocircinata (‘Golden Torch Adrian’ e ‘Golden Torch’) como esperado exibiram três cromossomos com marcação, dois semelhantes aos H. spathocircinata e outro ao de H. psittacorum. Nos genótipos triploides ‘Sassy’ e ‘Suriname Sassy’, foram observados três cromossomos com marcação subterminal e presença de satélite semelhante ao encontrado para H. psittacorum. Para H. bihai, destacaram-se dois cromossomos com marcação proximal. O híbrido H. caribaea x H. bihai cv. Jacquinii também apresentou dois cromossomos portadores sítios de CMA++/DAPI-/DNAr 45S proximal, porém heteromórficos para tamanho e morfologia. A distribuição dos sítios de DNAr 5S e 45S, ambos CMA positivos, corroborou a origem dos genótipos triploides ‘Sassy’ e ‘Suriname Sassy’ a partir de genótipos diploides de H. psittacorum bem como de híbridos H. psittacorum x H. spathocircinata (‘Golden Torch’ e ‘Golden Torch Adrian’) e H. caribaea x H. bihai cv. Jacquinii a partir de seus respectivos parentais.
16

Citogenetica de Dendropsophus (Anura, Hylidae) : caracterizações e comparações cromossomicas entre especies relacionadas / Cytogenetic of Dendropsophus (Anura, Hylidae)

Medeiros, Lilian Ricco 26 August 2005 (has links)
Orientador: Shirlei Maria Recco-Pimentel / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T10:17:17Z (GMT). No. of bitstreams: 1 Medeiros_LilianRicco_D.pdf: 1840995 bytes, checksum: 62f07c7258ee38a9d84632b39e51a61c (MD5) Previous issue date: 2005 / Resumo: No presente estudo caracterizamos e comparamos citogeneticamente populações de sete espécies de Dendropsophus (Hylinae) proximamente relacionadas e que apresentam morfologia externa semelhante: D. nanus (Botucatu, SP; Bodoquena, MS; Telêmaco Borba, PR; Bacabal, MA), D. walfordi (entre Rio Madeira e Pacaás, RO), D. sanborni (Torres, RS), D. jimi (Uberlândia, MG), D. rubicundulus (Uberlândia, MG), D. elianeae (Botucatu, SP; Nova Itapirema, SP; Bodoquena, MS) e D. minutus (Vitória Brasil, SP; Bodoquena, MG). As metáfases foram obtidas a partir de suspensões de células do epitélio intestinal e de testículo. As lâminas foram coradas com solução de Giemsa 10% ou submetidas às técnicas de banda C e de impregnação por prata (Ag-NOR) e hibridação in situ fluorescente. Os dados citogenéticos revelaram a presença de 2n=30 cromossomos em todas espécies, exceto em alguns indivíduos de D. nanus, que apresentaram até três cromossomos B pequenos, todos telocêntricos e univalentes na meiose. Todas as espécies apresentaram pequena quantidade de heterocromatina, localizada somente na região centromérica. No entanto, alguns indivíduos de D. nanus de Telêmaco Borba (PR) e de D. rubicundulus de Uberlândia (MG) apresentaram um pequeno bloco de heterocromatina intersticial no par 3 e no par 12, respectivamente, caracterizando uma variação intrapopulacional. A região organizadora do nucléolo (NOR) foi detectada em um único par cromossômico nas diferentes espécies. Um indivíduo de D. sanborni apresentou um heteromorfismo no par 12 devido a uma duplicação da NOR em um dos homólogos. As populações de D. nanus provenientes de Telêmaco Borba (PR), Bacabal (MA) e Serra da Bodoquena (MS) e a de D. walfordi coletada entre os rios Madeira e Pacaás (RO) apresentaram cariótipos idênticos, com 2n=30 e NF=52. Um espécime de D. nanus da Serra da Bodoquena, apresentou NF=51 devido a um heteromorfismo no par 6, em que um dos homólogos é metacêntrico e o outro telocêntrico, provavelmente devido a uma inversão do tipo pericêntrica. Em todos os espécimes, a NOR foi localizada no par metacêntrico 13. Dendropsophus sanborni proveniente de Botucatu (SP) e Torres (RS) e D. jimi de Uberlândia (MG) também apresentaram cariótipos idênticos, com 2n=30 e NF=50, diferindo das outras duas espécies pela presença de cinco telocêntricos em vez de quatro, com a NOR localizada no par telocêntrico 12. Não foram observadas diferenças citogenéticas entre as populações de D. nanus e entre as de D. sanborni, e nem destas com as outras populações já descritas na literatura. Os cromossomos B presentes em duas populações de D. nanus não apresentaram heterocromatina e nem genes ribossomais. Dendropsophus elianeae apresentou três pares de telocêntricos e a NOR no par 11, enquanto D. rubicundulus apresentou apenas dois telocêntricos e a NOR no par 5. As duas populações de D. minutus apresentaram o mesmo cariótipo já descrito para outras populações, com ausência de cromossomo do tipo telocêntrico. A NOR nessa espécie foi detectada no par 9. Os dados citogenéticos do presente trabalho não permitiram distinguir D. nanus de D. walfordi, nem D. sanborni de D. jimi, sugerindo que são espécies muito intimamente relacionadas. Dendropsophus elianeae e D. rubicundulus foram até pouco tempo consideradas como uma única espécie e D. rubicundulus foi por muito tempo erroneamente denominada de D. elongata. Essas espécies foram facilmente diferenciadas pelo número de telocêntricos e pela localização da NOR. Diferem também de D. elongata, descrita na literatura, que possui apenas um par de telocêntricos. Nenhuma diferença siginificativa foi detectada entre os cariótipos das três populações de D. elianeae. Portanto, os dados citogenéticos corroboraram o status taxonômico atual de D. elianeae e D. rubicundulus. Rearranjos do tipo inversão e translocação devem ter ocorrido durante a diferenciação das espécies de Dendropsophus, levando a modificação na morfologia dos cromossomos e à migração da NOR no genoma, sem alterar o número de cromossomos / Abstract: In the present study we characterized and compared cytogenetically populations of seven closely related Dendropsophus (Hylinae), a group of 30 chromosomes species, that show similar external morphology: D. nanus (Botucatu, SP; Bodoquena, MS; Telêmaco Borba, PR; Bacabal, MA), D. walfordi (between Rio Madeira and Pacaás, RO), D. sanborni (Torres, RS), D. jimi (Uberlândia, MG), D. rubicundulus (Uberlândia, MG), D. elianeae (Botucatu, SP; Nova Itapirema, SP; Bodoquena, MS) e D. minutus (Vitória Brasil, SP; Bodoquena, MG). The metaphases were obtained from intestinal epithelium and testis cell suspensions. The slides were stained with 10% Giemsa solution or submitted to the C-band (King, 1980), silver staining (Ag-NOR) and in situ fluorescence hybridization techniques. All species had 2n=30 chromosomes, except some individuals of D. nanus, which showed up to three little B-chromosomes, all telocentrics. These chromosomes were univalent in meiosis. All the species presented a little amount of heterochromatin, located only in the centromeric region. However, some individuals of D. nanus from Telêmaco Borba (PR) and of D. rubicundulus from Uberlândia (MG) had a little block of interstitial heterochromatin in the pair 3 (D. nanus) and in the pair 12 (D. rubicundulus), characterizing an intra-populational variation. The nucleolar organizing region (NOR) was detected in only one chromosomal pair in all species. An individual of D. sanborni had one heteromorphism due to a duplication of the NOR in one of the homologues of the pair 12. Dendropsophus nanus from Telêmaco Borba (PR), Bacabal (MA) and Serra da Bodoquena (MS) and of D. walfordi collected between the Madeira and Pacaás rivers (RO) showed identical karyotypes, with 2n=30 and NF=52. A specimen of D. nanus from Serra da Bodoquena presented NF=51 due to an heteromorphism in the pair 6, in which one of the homologues is metacentric and the other is telocentric, probably because of a pericentric inversion. In all the specimens, the NOR was located in the metacentric pair 13. Dendropsophus sanborni from Botucatu (SP) and Torres (RS), and D. jimi from Uberlândia (MG) also had identical karyotypes, with 2n=30 e NF=50, differing from the other two species by the presence of five telocentrics instead of four, with the NOR located in the telocentric pair 12. We did not observe citogenetic differences between the populations of D. nanus and of D. sanborni, neither differences among these populations and others already described in the literature. The B-chromosomes found in two populations of D. nanus did not showed heterochromatin neither ribosomal genes. Dendropsophus elianeae had three pairs of telocentric and the NOR in the pair 11. In contrast, D. rubicundulus presented only two telocentrics and the NOR in the pair 5. The two populations of D. minutus had the same karyotype already described for other populations, with absence of telocentric chromosome. The NOR was detected in the pair 9. The cytogenetic data presented here did not permit to distinguish D. nanus from D. walfordi, neither D. sanborni from D. jimi, suggesting that these species are very closely related. Dendropsophus elianeae and D. rubicundulus were until recently considered as a unique species, and for a long time D. rubicundulus was erroneously denominated as D. elongata. These species were easily distinguished from each other by the number of telocentrics and location of the NOR. They also differ from the D. elongata, described in the literature, which has only one pair of telocentric. No significant difference was detected among the karyotypes of the three populations of D. elianeae. Hence, the cytogenetic data confirm the current taxonomic status of D. elianeae and of D. rubicundulus. Rearrangements, such as inversion and translocation, should have occurred during the differentiation of these species, driving the changes in the chromosome morphology and the migration of the NOR in the genome, without modifying the chromosomal number / Doutorado / Biologia Celular / Doutora em Biologia Celular e Estrutural
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Diversidade genética de hilídeos do Brasil Central / Genetic diversity hylids Central Brazil

Oliveira, Hugo Henrique Pádua de 26 June 2012 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2014-11-10T16:56:23Z No. of bitstreams: 2 Dissertação - Hugo Henrique Pádua de Oliveira- 2012.pdf: 1742065 bytes, checksum: 7bac69420ca8a041766ecff769ec955c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-11-10T20:01:15Z (GMT) No. of bitstreams: 2 Dissertação - Hugo Henrique Pádua de Oliveira- 2012.pdf: 1742065 bytes, checksum: 7bac69420ca8a041766ecff769ec955c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-10T20:01:15Z (GMT). No. of bitstreams: 2 Dissertação - Hugo Henrique Pádua de Oliveira- 2012.pdf: 1742065 bytes, checksum: 7bac69420ca8a041766ecff769ec955c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-06-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The anurans are a group of vertebrates with wide geographical distribution that obtained highly evolutionary success, being part of a lineage descendant of early tetrapods, the first vertebrates to conquer the terrestrial environment. Anurans are divided into two suborders: Archaeobatrachia and Neobatrachia. Within the suborder Neobatrachia there is Bufonoidea superfamily, which includes the three families of higher abundance in the neotropical region: Leptodactylidae, Bufonidae and Hylidae. The aim of this study was to analyze cytogenetically species of the family Hylidae of areas of the Cerrado of Goiás, by the technique of conventional cytogenetics and by silver nitrate staining. The metaphases were obtained directly from cell suspensions of spleen, liver and bone marrow. The slides were stained with Giemsa at 8%, to determine the diploid number and chromosome morphology. The species Hypsiboas multifasciatu and Hypsiboas raniceps presented the diploid number 2n=24 and fundamental number FN=48 with positive marks for NORs in chromosomes 8 and 10 respectively. The species Hypsiboas lundii presented diploid number 2n=24 and fundamental number FN=46 due to the presence of acrocentric chromosome in pair 6. The RONs for this species were identified in pericentromeric regions of short arms of chromosome 5 and in telomeric regions of short arms of chromosome 8. Within the genus Hypsiboas, only the species Hypsiboas albopunctatus presented diploid number 2n=22 and fundamental number FN = 44, and by silver staining technique we identified the presence of NORs on the short arms of the telomeric regions of chromosome pair 8. The species Pseudis bolbodactyla presented diploid number 2n=24 and FN=46 evidenced by the acrocentric pair 4. The species Scinax similis and Scinax constrictus showed different karyotypic notations. The species Scinax similis presented karyotype 2n=24 and FN=48 with methacentric and submethacentric chromosomes. We found for the species Scinax constrictus the karyotype notation 2n=22 and FN=44. Differences in the morphology of chromosomes with respect to literature data can be explained by the different criteria used for classification of the chromosomes. The morphology of some of the chromosomes found in this study differs from their representatives described in the literature, and such differences may be explained by adopting different criteria for the classification of chromosomes. / Os anuros são um grupo de vertebrados de ampla distribuição geográfica que obtiveram um grande sucesso evolutivo, fazendo parte de uma linhagem descendente dos primeiros tetrápodes, os primeiros vertebrados a conquistarem o ambiente terrestre. Os anuros encontram-se divididos em duas subordens: Archaeobatrachia e Neobatrachia. Dentro da subordem Neobatrachia há a superfamília Bufonoidea, que inclui as três famílias de maior abundância na região neotropical: Leptodactylidae, Bufonidae e Hylidae. O objetivo desse estudo foi analisar citogeneticamente espécies da família Hylidae de áreas do cerrado goiano, pela técnica de citogenética convencional e pela coloração por nitrato de prata. As metáfases foram obtidas diretamente a partir de suspensões celulares de baço, fígado e medula óssea. As lâminas foram coradas com Giemsa a 8%, para determinação do número diplóide e morfologia cromossômica. As espécies Hypsiboas multifasciatus e Hypsiboas raniceps apresentaram o número diplóide 2n=24 e número fundamental NF=48 com marcações positivas para as RONs nos pares cromossômicos 8 e 10 respectivamente. Já a espécie Hypsiboas lundii apresentou número diplóide 2n=24 e número fundamental NF=46 devido a presença do cromossomo acrocêntrico no par 6. As RONs para esta espécie foram identificadas em regiões pericentroméricas dos braços curtos do cromossomo 5 e em regiões teloméricas dos braços curtos do cromossomo 8. Dentro do gênero Hypsiboas, apenas a espécie Hypsiboas albopunctatus apresentou número diplóide 2n=22 e o número fundamental NF = 44, sendo que a técnica de coloração por prata identificou a presença de RONs nos braços curtos das regiões teloméricas do par cromossômico 8. A espécie Pseudis bolbodactyla apresentou número diplóide 2n=24 e NF=46 evidenciado pelo par acrocêntrico 4. As espécies do gênero Scinax apresentaram diferentes notações cariotípicas. Scinax similis apresentou cariótipo 2n=24 e NF=48 com os cromossomos metacêntricos e submetacêntricos, enquanto que Scinax constrictus apresentou notação cariotípica 2n=22 e NF=44. A morfologia de alguns dos cromossomos encontrados no presente estudo difere de seus representantes descritos na literatura. As diferenças observadas podem ser explicadas através da adoção de diferentes critérios utilizados para a classificação dos cromossomos.
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Caractérisation génétique du genre Iris évoluant dans la méditerranée orientale / Genetic characterization of Iris genus evovlving in the East Mediterranean region

Abdel Samad, Nour 21 September 2016 (has links)
Le genre Iris appartenant à la famille des Iridacées comprend plus de 220 espèces distribuées à travers l’hémisphère Nord. La section Oncocyclus (Siems.) Baker de ce genre est confinée au Sud-ouest de l’Asie et comprend plus de 65 espèces au statut taxonomique souvent discuté.La présente étude porte sur le complexe d’espèces d’Iris évoluant dans les pays de la Méditerranée orientale : Liban, Syrie, Jordanie, Palestine/Israël, Arménie, Turquie et Iran.Le taux d’endémisme au sein de ce genre est relativement élevé et la cueillette excessive ainsi que la destruction de leurs habitats menace un grand nombre de ces espèces.En vue de préciser le statut taxonomique des espèces et d’élucider les relations phylogénétiques qui les relient plusieurs méthodes sont employées : l’analyse de la taille du génome, l’étude du caryotype, l’organisation du génome basée sur la localisation des gènes ribosomiques et l’étude de la structuration de la diversité génétique et la phylogénie basée sur des marqueurs moléculaires nucléaires et chloroplastiques.Les études de laboratoires sont complétées par des travaux de terrain afin de suivre l’évolution de la dynamique des taxons endémiques du Liban en vue de leur préservation.Au cours de notre étude, les régions ITS, TrnL-F et matk de tous les iris du Liban et 20 Oncocylus de la région Est-Méditerranéenne ont été séquencées pour construire les arbres phylogénétiques. Les deux techniques FISH et Feulgen ont été appliquées sur plusieurs espèces Oncocyclus du Liban. Des études cytogénétiques approfondies ont été menées sur toutes les espèces d’Iris collectées. / The Iris genus belonging to the Iridaceae family includes over 220 species distributed throughout the Northern Hemisphere. The Oncocyclus section (Siems.) Baker is confined to the Southwest Asia and includes more than 65 species with a discussed taxonomic status.This study focuses on the Iris species complex evolving in the countries of the Eastern Mediterranean Region: Lebanon, Syria, Jordan, Palestine / Israel, Armenia, Turkey and Iran.The rate of endemism within this genus is relatively high. The overharvesting and the destruction of their habitats threaten many of its species.To clarify the taxonomic status of the species and to elucidate the phylogenetic relationships that connect them, several methods are used: the analysis of the genome size, the study of the karyotype, genome organization based on the ribosomal genes location and the study of genetic diversity and phylogeny based on nuclear and chloroplast molecular markers.Laboratory studies are complemented by field work to monitor the dynamics of Lebanon's endemic taxa for their preservation.In our study, the ITS regions, trnL-F and matK of all Lebanese irises and 20 Oncocylus irises of the East Mediterranean region were sequenced to construct phylogenetic trees. Both techniques FISH and Feulgen were applied to several Lebanese Oncocyclus species. Extensive cytogenetic studies have been conducted on all species of collected Iris taxa.
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Přínos molekulárně genetických a cytogenetických analýz k diagnostice a predikci léčebné odpovědi u pacientů s non-Hodgkinskými lymfomy / The role of molecular genetic and cytogenetic analyses in the diagnosis and prediction of treatment response in patients with non-Hodgkin lymphomas

Berková, Adéla January 2014 (has links)
Malignant lymphoproliferative disorders include highly heterogeneous entities, i.e. lymphomas (Non-Hodgkin - NHL, as well Hodgkin's lymphoma), lymphoid leukemias, multiple myeloma and others. As currently many chromosomal aberrations with diagnostic and prognostic significance are known, molecular cytogenetic analyses of tumor cell genome has become a substantial examination also in lymphoproliferative disorders. This thesis focuses primarily on chronic lymphocytic leukemia (CLL), which is one of the mature B-cell neoplasms and represents the most common type of leukemia. We analyzed four most frequently found aberrations (13q14 deletion, ATM and TP53 gene deletion, and trisomy 12) by fluorescence in situ hybridization (FISH) and also IgH gene aberrations in some patients. We compared the findings with other factors and clinical characteristics. This work shows that the conventional G-banding is analysis relatively little relevant. FISH was more effective in detecting aberrations in CLL. Although none of the four aforementioned changes is specific to CLL, the prognostic impact is significant, particularly that of TP53 deletion. Next, detection of some IgH gene translocations is essential in differential diagnosis of CLL and other NHL (follicular, mantle cell, diffuse large B cell, Burkitt's...
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Přínos molekulárně genetických a cytogenetických analýz k diagnostice a predikci léčebné odpovědi u pacientů s non-Hodgkinskými lymfomy / The role of molecular genetic and cytogenetic analyses in the diagnosis and prediction of treatment response in patients with non-Hodgkin lymphomas

Berková, Adéla January 2014 (has links)
Malignant lymphoproliferative disorders include highly heterogeneous entities, i.e. lymphomas (Non-Hodgkin - NHL, as well Hodgkin's lymphoma), lymphoid leukemias, multiple myeloma and others. As currently many chromosomal aberrations with diagnostic and prognostic significance are known, molecular cytogenetic analyses of tumor cell genome has become a substantial examination also in lymphoproliferative disorders. This thesis focuses primarily on chronic lymphocytic leukemia (CLL), which is one of the mature B-cell neoplasms and represents the most common type of leukemia. We analyzed four most frequently found aberrations (13q14 deletion, ATM and TP53 gene deletion, and trisomy 12) by fluorescence in situ hybridization (FISH) and also IgH gene aberrations in some patients. We compared the findings with other factors and clinical characteristics. This work shows that the conventional G-banding is analysis relatively little relevant. FISH was more effective in detecting aberrations in CLL. Although none of the four aforementioned changes is specific to CLL, the prognostic impact is significant, particularly that of TP53 deletion. Next, detection of some IgH gene translocations is essential in differential diagnosis of CLL and other NHL (follicular, mantle cell, diffuse large B cell, Burkitt's...

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