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Aline Souza Medrado Mavione Souza Ribeiro Paulo Roberto Antunes de Mello Affonso Paulo Luíz Souza Carneiro Marco Ant?nio Costa 《Genetics and molecular biology》2012,35(4):797-801
The fish genus Astyanax is widespread throughout the Neotropical region and is one of the most species-rich genera of the Characiformes. Cytogenetic studies of Astyanax have revealed marked intra- and interspecific diversity, with the identification of various species complexes. In this report, we describe the karyotypic structure of two sympatric species of Astyanax (Astyanax sp. and Astyanax aff. fasciatus) from the Middle Contas River basin in the northeastern Brazilian state of Bahia. Both species had 2n = 48 but differed in their karyotypic formulae. Small heterochromatic blocks and multiple nucleolar organizer regions (NORs) were identified in both species. Terminal CMA3+/DAPI− signals were observed in Astyanax sp. and A. aff. fasciatus, mostly coincident with NORs. These results show that chromosomal markers can be used to identify species in this fish complex. These markers can provide useful information for evolutionary studies and investigations on the mechanisms of chromosomal diversity in Astyanax. 相似文献
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Nívia Carolina Nogueira-Paiva Paula Melo de Abreu Vieira Larissa Maris Rezende Oliveri Kátia da Silva Fonseca Gwenaelle Pound-Lana Maykon Tavares de Oliveira Marta de Lana Vanja Maria Veloso Alexandre Barbosa Reis Washington Luiz Tafuri Cláudia Martins Carneiro 《PloS one》2015,10(9)
The present study aims at establishing whether the diversity in pathogenesis within a genetically diverse host population infected with a single polyclonal strain of Trypanosoma cruzi is due to selection of specific subpopulations within the strain. For this purpose we infected Swiss mice, a genetically diverse population, with the polyclonal strain of Trypanosoma cruzi Berenice-78 and characterized via LSSP-PCR the kinetoplast DNA of subpopulations isolated from blood samples collected from the animals at various times after inoculation (3, 6 and 12 months after inoculation). We examined the biological behavior of the isolates in acellular medium and in vitro profiles of infectivity in Vero cell medium. We compared the characteristics of the isolates with the inoculating strain and with another strain, Berenice 62, isolated from the same patient 16 years earlier. We found that one of the isolates had intermediate behavior in comparison with Berenice-78 and Berenice-62 and a significantly different genetic profile by LSSP-PCR in comparison with the inoculating strain. We hereby demonstrate that genetically distinct Trypanosoma cruzi isolates may be obtained upon experimental murine infection with a single polyclonal Trypanosoma cruzi strain. 相似文献
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Nisin stimulates oxygen consumption by Staphylococcus aureus and Escherichia coli. 总被引:2,自引:2,他引:0 下载免费PDF全文
Nisin stimulated oxygen consumption by nongrowing, glucose-metabolizing Staphylococcus aureus and Escherichia coli cells, indicating a protonophore mode of action. A similar stimulation in E. coli cells osmotically stressed to disrupt the outer cell membrane confirmed the cytoplasmic membrane as the site of nisin action and showed that nisin uptake was not prevented by the outer membrane. 相似文献
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Isa Carneiro Snia Carvalho Rui Henrique Luís M. Oliveira Valery V. Tuchin 《Journal of biophotonics》2019,12(4)
A robust method is presented for evaluating the diffusion properties of chemicals in ex vivo biological tissues. Using this method that relies only on thickness and collimated transmittance measurements, the diffusion properties of glycerol, fructose, polypropylene glycol and water in muscle tissues were evaluated. Amongst other results, the diffusion coefficient of glycerol in colorectal muscle was estimated with a value of 3.3 × 10?7 cm2/s. Due to the robustness and simplicity of the method, it can be used in other fields of biomedical engineering, namely in organ cryoprotection and food industry. 相似文献
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