|
|
|
Registros recuperados: 94 | |
|
| |
|
|
Laguna,Marcia Maria; Amaro,Renata Cecília; Mott,Tamí; Yonenaga-Yassuda,Yatiyo; Rodrigues,Miguel Trefaut. |
The karyotype of Amphisbaena ridleyi, an endemic species of the archipelago of Fernando de Noronha, in State of Pernambuco, Brazil, is described after conventional staining, Ag-NOR impregnation and fluorescence in situ hybridization (FISH) with a telomeric probe. The diploid number is 46, with nine pairs of macrochromosomes (three metacentrics, four subtelocentrics and two acrocentrics) and 14 pairs of microchromosomes. The Ag-NOR is located in the telomeric region of the long arm of metacentric chromosome 2 and FISH revealed signals only in the telomeric region of all chromosomes. Further cytogenetic data on other amphisbaenians as well as a robust phylogenetic hypothesis of this clade is needed in order to understand the evolutionary changes on... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amphisbaena ridleyi; Karyotype; Fernando de Noronha; Ag-NOR; FISH with telomeric probes. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000100011 |
| |
|
|
Costa,Kleber França; Brito,Rute Magalhães; Miyazawa,Carlos Suetoshi. |
The genus Trigona contains at least 31 species, but there have been few cytogenetic studies of this group. In this work, four species of Trigona (T. branneri, T. chanchamayoensis, T. hyalinata, and T. recursa) from the municipality of Cuiabá, in the State of Mato Grosso, Brazil, were studied. In all of the species, the females had 2n = 34 chromosomes and the males had n = 17. The C-banding patterns showed that the karyotypes of these species consisted mainly of acrocentric and pseudoacrocentric chromosomes. These cytogenetic findings should useful in future phylogenetic studies of this group. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; Karyotype; Meliponini; Stingless bees; Trigona. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000200010 |
| |
|
|
Schneider,Marielle Cristina; Carraro,Bianca Pierina; Cella,Doralice Maria; Matiello,Rodrigo Rodrigues; Artoni,Roberto Ferreira; Almeida,Mara Cristina. |
In this work we describe the cytogenetic analyses performed in specimens of Astylus variegatus (Germar, 1824) collected in two localities: one area of natural vegetation and one of agricultural crops, where agrochemical products were used. Astylus variegatus had karyotypes with 2n(male) = 16+Xy p and 2n (female) = 16+XXp, with exclusively metacentric chromosomes. Pachytene spermatocytes showed synapsed autosomal bivalents and non-associated sex chromosomes. In diplotene, the autosomal bivalents exhibited one or two terminal chiasmata and the Xy p had a typical parachute configuration. In meiotic cells of some specimens, an extra chromosome, interpreted as a B chromosome, was observed. C-banding showed constitutive heterochromatin in the pericentromeric... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: B chromosome; Constitutive heterochromatin; Karyotype; Meiosis; Ag-NORs. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000400023 |
| |
|
|
Arcanjo,Amanda; Cabral-de-Mello,Diogo Cavalcanti; Martins,Cesar; Moura,Rita de Cássia de; Souza,Maria José de. |
The genus Phanaeus is included in the tribe Phanaeini, one of the most diverse tribes within the subfamily Scarabaeinae in terms of chromosomal characteristics. However, so far the species of this genus were not studied with differential cytogenetic techniques, limiting any inference of the probable mechanisms responsible for this diversity. In this work, several techniques were applied with the aim of cytogenetically characterizing two Phanaeus species. The karyotype found for Phanaeus (Notiophanaeus) chalcomelas was 2n = 12, neo-XY, and that of P. (N.) splendidulus was 2n = 20, Xy p, considered primitive for the family Scarabaeidae. The chromosomes of both species showed a high amount of constitutive heterochromatin (CH), with blocks rich in base pairs... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Chromosome evolution; Repetitive DNA; FISH. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000300007 |
| |
|
|
Franco-de-Sá,Jorge Felipe Oliveira; Rosas,Fernando César Weber; Feldberg,Eliana. |
The giant otter, Pteronura brasiliensis Zimmermann 1780 (Carnivora, Mustelidae, Lutrinae), was widely distributed in South America but stable populations are now only found in the Pantanal and Amazon regions and the species is classified as endangered. There is only one recognized species of giant otter, although two subspecies of doubtful value have also been cited in the literature. We present the first karyotype of four captive P. brasiliensis specimens, all of which posses 2n = 38 chromosomes as 14M+8SM+6ST+8A and one pair of sexual chromosomes. An heteromorphic secondary constriction, associated with the nucleolar organizer region (NOR), was seen on the long arms of chromosome pair 17. The C-banding technique revealed heterochromatin in the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amazon; Aquatic mammals; Ariranha; Karyotype. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000600011 |
| |
|
|
Bhaumik,Pranami; Ghosh,Priyanka; Ghosh,Sujay; Feingold,Eleanor; Ozbek,Umut; Sarkar,Biswanath; Dey,Subrata Kumar. |
Abstract Alzheimer's disease and Down syndrome often exhibit close association and predictively share common genetic risk-factors. Presenilin-1 (PSEN-1) and Apolipoprotein E (APOE) genes are associated with early and late onset of Alzheimer's disease, respectively. Presenilin −1 is involved in faithful chromosomal segregation. A higher frequency of the APOE ε4 allele has been reported among young mothers giving birth to Down syndrome children. In this study, 170 Down syndrome patients, grouped according to maternal meiotic stage of nondisjunction and maternal age at conception, and their parents were genotyped for PSEN-1 intron-8 and APOE polymorphisms. The control group consisted of 186 mothers of karyotypically normal children. The frequencies of the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome; Genetic polymorphism; Karyotype; Meiosis; Microsatellite markers. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572017000400577 |
| |
|
| |
|
| |
|
|
Speranza,Pablo; Vaio,Magdalena; Mazzella,Cristina. |
Paspalum quadrifarium Lam. is a bunchgrass native to Uruguay, Argentina, and southern Brazil. Diploid, triploid, tetraploid and hexaploid cytotypes have been reported for this species of the Quadrifaria group of Paspalum. In this group, a high degree of cytogenetic homology between the genomes of several diploid species has been reported, based on meiotic pairing in interspecific hybrids; multivalent associations would thus be expected in polyploid hybrids. Karyotype analysis could provide useful information about the genomic architecture of polyploid plants; however, the fully condensed mitotic chromosomes of Paspalum do not provide enough morphological features for such an analysis. In this paper, we used mitotic prometaphase chromosomes treated with 70%... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Meiosis; Prometaphase; Grasses; Paspalum. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000400013 |
| |
|
|
Targueta,Cíntia Pelegrineti; Guerra,Vinícius; Gambale,Priscilla Guedes; Bastos,Rogério Pereira; Silva,Daniela de Melo e; Telles,Mariana Pires de Campos. |
Abstract Cytogenetic data can be useful for taxonomic and phylogenetic studies, as well as to provide information about chromosome evolution. Therefore, it may help design conservation priorities for some threatened species, such as anurans. Herein, we describe the karyotypes of Scinax constrictus and Ololygon centralis, native endemic species from the Brazilian Cerrado. Chromosome preparations for both species were stained with Giemsa for morphological analyses and then impregnated by the Ag-NOR method for localization of the nucleolar organizer region (NOR). Both species had 24 chromosomes, as confirmed by meiotic analyses, which showed 12 bivalents. Chromosome morphologies presented the same pattern for Scinax and Ololygon compared to species already... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anura; Karyotype; Ololygon; Scinax. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000500814 |
| |
|
| |
|
|
Baeza,Carlos; Finot,Víctor L.; Ruiz,Eduardo. |
Alstroemeria L., one of the most diverse genera of the Chilean flora and of high floricultural value, is represented by 35 species, most of them distributed between 28–38° S in the Mediterranean zone of Central Chile. There are 24 complex-forming taxa, of which 18 have conservation problems (8 are considered “endangered” and 10 as “vulnerable”). One of these complexes is Alstroemeria presliana Herb. with two subspecies: subsp. presliana and subsp. australis Bayer. Alstroemeria presliana grows in Chile and Argentina: subsp. presliana is distributed from Reserva Nacional Siete Tazas (35°27′ S, Region of Maule) to Antuco, (37°25′ S, Region of Bío-Bío), and is also found in Neuquén, Argentina; subsp. australis is endemic to the Cordillera of Nahuelbuta. A... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alstroemeria; Asymmetry; Chile; Karyotype; Species complex. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000200199 |
| |
|
| |
|
|
Castanhole,Márcia Maria Urbanin; Pereira,Luis Lênin Vicente; Souza,Hederson Vinicius de; Valério,José Raul; Barbosa,Leonardo Rodrigues; Itoyama,Mary Massumi. |
Spittlebugs annually infest pastures and cause severe damage, representing a serious problem for the tropical American beef cattle industry. Spittlebugs are an important biotic constraint to forage production and there is a lack of cytogenetic data for this group of insects. For these reasons, we conducted this work, in which the spermatogenesis and nucleolar behavior of Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana were studied. The males possessed testes in the shape of a "bunch of grapes"; a variable number of testicular lobes per individual and polyploid nuclei composed of several heteropycnotic bodies. A heteropycnotic area was located in the periphery of the nucleus (prophase I); the chiasmata were terminal or interstitial;... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomal characterization; Karyotype; Cytogenetics; Spermatogenesis; Holocentric chromosomes. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200008 |
| |
|
| |
|
| |
|
|
Gunski,Ricardo José; Cunha,Isabel Souza; Degrandi,Tiago Marafiga; Ledesma,Mario; Garnero,Analía Del Valle. |
Podocnemis expansa and P. unifilis present 2n = 28 chromosomes, a diploid number similar to those observed in other species of the genus. The aim of this study was to characterize these two species using conventional staining and differential CBG-, GTG and Ag-NOR banding. We analyzed specimens of P. expansa and P. unifilis from the state of Tocantins (Brazil), in which we found a 2n = 28 and karyotypes differing in the morphology of the 13th pair, which was submetacentric in P. expansa and telocentric in P. unifilis. The CBG-banding patterns revealed a heterochromatic block in the short arm of pair 13 of P. expansa and an interstitial one in pair 13 of P. unifilis, suggesting a pericentric inversion. Pair 14 of P. unifilis showed an insterstitial band in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome banding; Ag-NORs; Karyotype; Chelonids. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000300009 |
| |
|
|
Ventura,Karen; Ximenes,Gilson Evaristo Iack; Pardini,Renata; Sousa,Marcos A. Nóbrega de; Yonenaga-Yassuda,Yatiyo; Silva,Maria José de J.. |
The genus Callistomys belongs to the rodent family Echimyidae, subfamily Echimyinae, and its only living representative is Callistomys pictus, a rare and vulnerable endemic species of the state of Bahia, Brazil. Callistomys has been previously classified as Nelomys, Loncheres, Isothrix and Echimys. In this paper we present the karyotype of Callistomys pictus, including CBG and GTG-banding patterns and silver staining of the nucleolus organizer regions (Ag-NORs). Comments on Callistomys pictus morphological traits and a compilation of Echimyinae chromosomal data are also included. Our analyses revealed that Callistomys can be recognized both by its distintinctive morphology and by its karyotype. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Callistomys; Karyotype; Banding patterns; Echimyinae. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000400016 |
| |
|
|
Vicari,Marcelo Ricardo; Almeida,Mara Cristina de; Bertollo,Luiz Antonio Carlos; Moreira-Filho,Orlando; Artoni,Roberto Ferreira. |
We used differential staining techniques (BSG, GTG, AgNO3, DAPI and CMA3 banding) and fluorescent in situ hybridization (FISH) with 5S and 18S probes to investigated the karyotypic and cytogenetic chracteristics of Prochilodus lineatus specimens from a population in Vila Velha state park (Parque Estadual de Vila Velha, Ponta Grossa, Paraná state, southern Brazil). The specimens studied showed the same karyotype as that found in other P. lineatus populations, i.e. 2n = 54 biarmed chromosomes (40m + 14 sm) and c-positive heterochromatin preferentially located pericentromerically in all chromosomes. The presence of partial or totally heterochromatic supernumerary chromosomes with numeric intra-individual variation was confirmed in the analyzed population. The... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish cytogenetics; Prochilodus; Karyotype; Minor and major rDNA; NOR polymorphism. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000400008 |
| |
Registros recuperados: 94 | |
|
|
|