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1.
Biochem Biophys Rep ; 24: 100814, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-33015376

RÉSUMÉ

A major challenge in hepatitis C research is the detection of early potential for progressive liver disease. MicroRNAs (miRNAs) are small RNAs that regulate gene expression and can be biomarkers of pathological processes. In this study, we compared circulating miRNAs identified in hepatitis C virus (HCV)-infected patients presenting two extremes of liver disease: mild/moderate fibrosis and cirrhosis. The patients in the cirrhosis group subsequently developed hepatocellular carcinoma (HCC). We identified 163 mature miRNAs in the mild/moderate fibrosis group and 171 in the cirrhosis group, with 144 in common to both groups. Differential expression analysis revealed 5 upregulated miRNAs and 2 downregulated miRNAs in the cirrhosis group relative to the mild/moderate fibrosis group. Functional analyses of regulatory networks (target gene and miRNA) identified gene categories involved in cell cycle biological processes and metabolic pathways related to cell cycle, cancer, and apoptosis. These results suggest that the differentially expressed circulating miRNAs observed in this work (miR-215-5p, miR-483-5p, miR-193b-3p, miR-34a-5p, miR-885-5p, miR-26b-5p and miR -197-3p) may be candidates for biomarkers in the prognosis of liver disease.

2.
Genet Mol Res ; 16(3)2017 Sep 27.
Article de Anglais | MEDLINE | ID: mdl-28973721

RÉSUMÉ

Mocó cotton belong to the same species as the cultivated species, Gossypium hirsutum, and cultivated forms were mainly landraces but also developed as cultivars, bearing good fiber quality and drought tolerant when cropped as a perennial species. The northeast Brazil crop system based on this cotton type is finished, with a few small area planted in the three main States, where it was previously cultivated (Ceará, Paraíba, and Rio Grande do Norte), but in others, maintenance is accomplished by single dooryard plants. Plants were found in all visited Northeast Brazil municipalities, sometimes in the North of the country, and were collected for ex situ preservation and evaluation. Most of seeds had no fuzz (62.2%) and 94.6% of the genotypes presented spot in flowers. Seventy-one alleles were revealed in 12 loci. The genetic structure of the population evaluated by microsatellite markers shows two main groups, one comprising the Seridó region where landraces were originated and other comprising the state of Ceará, where a specific breeding program was developed. Genotypes collected in North Brazil States as well as those collected in Bahia, Alagoas, and Sergipe grouped with those collected in Ceará. The Mantel correlogram indicates a significant (P < 0.05) correlation between genetic and geographical distances up to 77 km. The ex situ maintenance and agronomical evaluation are the main concerns for mocó, as the use of the agricultural interesting traits, possibly introgressed to other genotypes, is predicted. The in situ preservation is still of interest since there is more diversity there than in the collected plants and some should be continued due to use as medicinal plant.


Sujet(s)
Pool des gènes , Gossypium/génétique , Polymorphisme génétique , Brésil , Écosystème , Évolution moléculaire , Génotype , Caractère quantitatif héréditaire , Graines/génétique , Reproduction sélective
3.
Genet Mol Res ; 16(3)2017 Sep 21.
Article de Anglais | MEDLINE | ID: mdl-28973770

RÉSUMÉ

The objective of this study was to analyze the diversity and discrimination of high-performance Brazilian rice cultivars using microsatellite markers. Twenty-nine rice cultivars belonging to EMBRAPA Arroz e Feijão germplasm bank in Brazil were genotyped by 24 SSR markers to establish their structure and genetic discrimination. It was demonstrated that the analyzed germplasm of rice presents an expressive and significant genetic diversity with low heterogeneity among the cultivars. All 29 cultivars were differentiated genetically, and were organized into two groups related to their upland and irrigated cultivation systems. These groups showed a high genetic differentiation, with greater diversity within the group that includes the cultivars for irrigated system. The genotyping data of these cultivars, with the morphological e phenotypical data, are valuable information to be used by rice breeding programs to develop new improved cultivars.


Sujet(s)
Oryza/génétique , Amélioration des plantes/méthodes , Polymorphisme génétique , Brésil , Hétérogénéité génétique , Génotype , Répétitions microsatellites , Oryza/croissance et développement , Amélioration des plantes/normes , Graines/génétique
4.
Genet Mol Res ; 14(2): 3387-99, 2015 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-25966105

RÉSUMÉ

Although the genus Tursiops has a worldwide distribution and is globally well-studied, some dolphin populations continue to face high risks of decline. Hence, it is necessary to assess the genetic diversity and structure of this genus to properly assess its conservation status and to implement appropriate management actions. In Brazil, genetic studies on this group remain rare, particularly for populations inhabiting offshore waters. Saint Peter and Saint Paul Archipelago (SPSPA) is a small group of islands located in the Mid- Atlantic Ridge, where recent studies of the Tursiops truncatus group indicate that individuals are resident throughout the year around the archipelago, exhibiting considerable site fidelity. A previous study with this group indicated that the individuals form an isolated population. To test this hypothesis, and describe the genetic diversity of SPSPA individuals, we assessed 12 microsatellite loci and a portion of the mitochondrial control region. Bayesian analysis revealed that SPSPA bottlenose dolphins form a unique population. In a phylogeographic perspective, we found that individuals from SPSPA shared mtDNA haplotypes with inshore and offshore individuals from North Atlantic, suggesting that they are not currently isolated from their conspecifics. Mirroring mtDNA findings, microsatellite analysis revealed that most of the pairs of individuals sampled seem to be unrelated (83.8%) and no indication of inbreeding, what would be expected if a small population such as SPSPA was reproductively isolated.


Sujet(s)
Grand dauphin/génétique , Animaux , Océan Atlantique , Théorème de Bayes , Brésil , ADN mitochondrial/génétique , Femelle , Variation génétique , Génétique des populations , Haplotypes , Iles , Région de contrôle de locus , Mâle , Répétitions microsatellites , Pedigree , Phylogenèse , Phylogéographie , Analyse de séquence d'ADN , Sexe-ratio
5.
Genet Mol Res ; 12(1): 597-609, 2013 Feb 27.
Article de Anglais | MEDLINE | ID: mdl-23512677

RÉSUMÉ

Gossypium mustelinum is the only cotton species native to Brazil; it is endemic to the semi-arid region of the northeast. The populations are found near perennial and semi-perennial sources of water, such as ponds or pools in intermittent streams. Problems with in situ conservation derive from human interference in its habitat, mainly because of excessive cattle grazing and deforestation. Establishing efficient strategies for in situ conservation requires knowledge of the genetic structure of the populations. We evaluated the structure and genetic variability of populations of G. mustelinum in the Tocó and Capivara Rivers (State of Bahia). Two hundred and eighteen mature G. mustelinum plants were genotyped with SSR markers. The molecular data were used to estimate the allelic frequencies, the heterozygosity, the F statistics, and the genetic distance among the populations and among individuals. We found high genetic diversity among the populations. The FST indexes for each population were also high and strongly correlated with physical distance. The high estimated level of endogamy and the low observed heterozygosity are indicative that the populations reproduce mainly by self-fertilization and crosses between related individuals. Consequently, strategies for in situ preservation should include at least three occurrence sites of G. mustelinum from each population. For ex situ conservation, the collections should include as many sites as possible.


Sujet(s)
Écosystème , Variation génétique , Gossypium/génétique , Répétitions microsatellites/génétique , Allèles , Animaux , Brésil , Bovins , ADN des plantes/composition chimique , ADN des plantes/génétique , Fréquence d'allèle , Structures génétiques , Génétique des populations , Génotype , Géographie , Gossypium/classification , Gossypium/croissance et développement , Humains , Phylogenèse , Rivières , Analyse de séquence d'ADN
6.
Rev. chil. obstet. ginecol ; 60(1): 28-33, 1995. tab
Article de Espagnol | LILACS | ID: lil-164872

RÉSUMÉ

El objetivo de este trabajo fue determinar la credibilidad del legrado endocervical como parte del estudio del cuello uterino de pacientes con citologías anormales. Para esto, se analizaron 108 pacientes sometidas a colposcopía, biopsias exocervicales y legrado endocervical sistemático, todas las cuales fueron posteriormente conizadas. Se comparó el resultado de las biopsias de ambos procedimientos, calculándose la sensibilidad (85 por ciento), especificidad (35 por ciento), valor predictivo positivo (62 por ciento) y valor predictivo negativo (65 por ciento) del legrado endocervical. Se concluye que la credibilidad del procedimiento es baja y se discute su utilidad en la toma de decisiones


Sujet(s)
Humains , Femelle , Colposcopie , Dilatation et curetage/méthodes , Tumeurs du col de l'utérus/anatomopathologie , Biopsie , Dysplasie du col utérin/anatomopathologie , Prévision , Sensibilité et spécificité
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