21 research outputs found

    Genetic diversity in cultivated carioca common beans based on molecular marker analysis

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    A wide array of molecular markers has been used to investigate the genetic diversity among common bean species. However, the best combination of markers for studying such diversity among common bean cultivars has yet to be determined. Few reports have examined the genetic diversity of the carioca bean, commercially one of the most important common beans in Brazil. In this study, we examined the usefulness of two molecular marker systems (simple sequence repeats – SSRs and amplified fragment length polymorphisms – AFLPs) for assessing the genetic diversity of carioca beans. The amount of information provided by Roger’s modified genetic distance was used to analyze SSR data and Jaccards similarity coefficient was used for AFLP data. Seventy SSRs were polymorphic and 20 AFLP primer combinations produced 635 polymorphic bands. Molecular analysis showed that carioca genotypes were quite diverse. AFLPs revealed greater genetic differentiation and variation within the carioca genotypes (Gst = 98% and Fst = 0.83, respectively) than SSRs and provided better resolution for clustering the carioca genotypes. SSRs and AFLPs were both suitable for assessing the genetic diversity of Brazilian carioca genotypes since the number of markers used in each system provided a low coefficient of variation. However, fingerprint profiles were generated faster with AFLPs, making them a better choice for assessing genetic diversity in the carioca germplasm

    High genetic diversity among and within bitter manioc varieties cultivated in different soil types in Central Amazonia

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    Although manioc is well adapted to nutrient-poor Oxisols of Amazonia, ethnobotanical observations show that bitter manioc is also frequently cultivated in the highly fertile soils of the floodplains and Amazonian dark earths (ADE) along the middle Madeira River. Because different sets of varieties are grown in each soil type, and there are agronomic similarities between ADE and floodplain varieties, it was hypothesized that varieties grown in ADE and floodplain were more closely related to each other than either is to varieties grown in Oxisols. We tested this hypothesis evaluating the intra-varietal genetic diversity and the genetic relationships among manioc varieties commonly cultivated in Oxisols, ADE and floodplain soils. Genetic results did not agree with ethnobotanical expectation, since the relationships between varieties were variable and most individuals of varieties with the same vernacular name, but grown in ADE and floodplain, were distinct. Although the same vernacular name could not always be associated with genetic similarities, there is still a great amount of variation among the varieties. Many ecological and genetic processes may explain the high genetic diversity and differentiation found for bitter manioc varieties, but all contribute to the maintenance and amplification of genetic diversity within the manioc in Central Amazonia. © 2017, Sociedade Brasileira de Genética

    Journal of Medical Virology

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    Texto completo: acesso restrito. p. 299–304Despite the marked reduction in the incidence of measles in Brazil, a measles epidemic occurred in this country in 1997. The measles cases observed during this epidemic began to reappear in large numbers in São Paulo, and spread to Rio de Janeiro and other Brazilian states. In the present study molecular biology techniques were used for the detection and genomic characterization of measles viruses from clinical samples such as urine and nasopharyngeal secretions collected in the states of Rio de Janeiro, Minas Gerais and Paraná, during the 1997 epidemic. RT-PCR and nucleotide sequence analysis of part of the carboxyl-terminal region of the nucleoprotein gene of measles viruses obtained directly from clinical samples or from infected cell cultures during this epidemic classified all as wild-type of genotype D6. As the genotype D6 was identified in different Brazilian states, this study demonstrated that this genotype was circulating in Brazil during the 1997 epidemic. J. Med. Virol. 63:299–304, 2001. © 2001 Wiley-Liss, Inc

    Mechanical Periodontal Therapy Recovered the Phagocytic Function of Monocytes in Periodontitis

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    Background. Several studies have focused on the association between periodontitis and systemic implications; however, the biological mechanisms of the immune responses before and after periodontal therapy involved in this relationship, such as phagocytic functions, remain unclear. Objectives. This study aimed to investigate whether periodontal treatment improves the phagocytic function of blood monocytes in patients with severe periodontitis. Materials and Methods. A nonrandomized sample of 55 participants was enrolled in the study. Two groups were studied: control (n = 27, healthy subjects without periodontal disease) and patients (n = 28, individuals with periodontitis). Treatment of periodontitis (scaling and root planing) was performed until the clinical resolution of periodontal pockets and inflammation. The following clinical periodontal parameters were assessed: probing depth, clinical attachment level, visible plaque index (PI), and gingival bleeding on probing index before and after mechanical periodontal treatment. The phagocytic index (PhI) and nitro blue tetrazolium test (NBT) were assessed before and immediately after the end of treatment. Results. Periodontitis induced impaired phagocytosis by monocytes. Phagocytosis at baseline was significantly lower in periodontitis patients [median, 13.2 (range of 7.1 to 20.8) and 60.7 (40.6 to 88.6)] than in controls [27.4 (15.5 to 40.5)] and 98 (68.2 to 122.9)] for nonsensitized or sensitized samples, respectively. After supportive therapy, patients showed a significant enhancement of phagocytic functions [33.7 (14.6 to 53.2) and 108.5 (99.6 to 159.5)] for nonsensitized and sensitized samples, respectively. Periodontal treatment increased the phagocytic capacity to a level similar to that observed in the control group and improved the capacity of phagocytes to produce superoxide anion. Conclusions. The results suggest that periodontal therapy in patients with severe periodontitis provides a state of homeostasis due to the reestablishment of phagocytic function and increased production of NBT (Regional Registry No. RBR-24T799; Universal Registry No. U1111-1133-5512)
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