139 resultados para Chromosomal aberrations
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Blood cell lymphocyte chromosomes from untreated (UT) and clinically-cured (CC) patients with paracoccidioidomycosis and from healthy (control) people (CO) were studied. The frequency of aneuploid cells in the UT patients was higher than in the CC and CO individuals. The frequency of metaphase cells with premature centromere division was significantly higher in the UT than in the CC and CO group. No structural aberration and no statistically significant difference in the frequency of polyploidy was observed in the three groups studied. Our findings are indicative of an aneugenic (aneuploidy-inducing) action of infection by Paracoccidioides brasiliensis.
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Karyotypes are compared of 14 species of Brazilian Columbiformes (family Columbidae): Claravis pretiosa (2n=74), Columba cayennensis (2n=76), Columba picazuro (2n=76), Columba speciosa (2n=76), Columbina minuta (2n=76), Columbina passerina (2n=76), Columbina picui (2n=76), Columbina talpacoti (2n=76), Geotrygon montana (2n=86), Leptotila rufaxilla (2n=76), Leptotila verreauxi (2n=78), Scardafella squammata (2n=78), Uropelia campestris (2n=68) and Zenaida auriculata (2n=76). The macrochromosomes of each species were analysed by conventional Giemsa staining, cytobiometrically and with G-and C-banding. All species studied are characterized by typical bird karyotypes with a few pairs of macrochromosomes and many microchromosomes. The morphology and relative length of the Z chromosome are nearly the same in all species, but the W chromosome shows variation. The G-band patterns of the first pair in Columbiformes show a large positive band distally in the long arm, common to all species of the order. The constitutive heterochromatin is restricted to the centromeres of the macro- and microchromosomes. The W is the most heterochromatic chromosome in all species studied. Studies of relative lengths, arm ratios and G- and C-banding patterns showed that in Columbiformes pairs 3, 4 and 5 are the most stable. The types of rearrangements distinguishing between species vary among the genera: pericentric inversions in Columba; fusions and translocations in Uropelia; centric fissions in Geotrygon; fusions, translocations, para and pericentric inversions in Columbina, Leptotila, Zenaida and Scardafella. On the basis of the karyological findings the phylogenetic relationships of the Brazilian Columbiformes are discussed. © 1984 Dr W. Junk Publishers.