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1.
Mol Phylogenet Evol ; 145: 106733, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31931136

RESUMEN

The Neotropical region harbors an astonishing diversity of species, but still encompasses the least studied biogeographic region of the world. These properties apply for different taxonomic groups, and can be exemplified by drosophilids. In fact, high levels of cryptic diversity have recently been discovered for Neotropical species of the Zygothrica genus group, but relationships among these species, or them and other Drosophilidae species still remains to be addressed. Therefore, the aim of this study was to evaluate the phylogenetic relationships between fungus-associated Neotropical species of the genera Hirtodrosophila, Mycodrosophila and Zygothrica, which together with Paramycodrosophila and Paraliodrosophila compose the Zygothrica genus group. For this, fragments of the mitochondrial cytochrome oxidase subunits I (COI) and II (COII) genes, and the nuclear alpha methyldopa (Amd) and dopa decarboxylase (Ddc) genes were newly characterized for 43 Neotropical specimens of fungus-associated drosophilids, and analyzed in the context of 51 additional Drosophilinae sequences plus one Steganinae outgroup. Based on the resulting phylogeny, the evolution of breeding sites usage was also evaluated through ancestral character reconstructions. Our results revealed the Zygothrica genus group as a monophyletic lineage of Drosophila that branches after the subgenera Sophophora and Drosophila. Within this lineage, Mycodrosophila species seem to encompass the early offshoot, followed by a grade of Hirtodrosophila species, with derived branches mostly occupied by representatives of Zygothrica. This genus, in particular, was subdivided into five major clades, two of which include species of Hirtodrosophila, whose generic status needs to be reevatuated. According to our results, the use of fungi as breeding sites encompasses a symplesiomorphy for the Zygothrica genus group, since one of the recovered clades is currently specialized in using flowers as breeding sites whereas a sole species presents a reversal to the use of fruits of a plant of Gentianales. So, in general, this study supports the paraphyly of Drosophila in relation to fungus-associated Neotropical species of Drosophilidae, providing the first molecular insights into the phylogenetic patterns related to the evolution of this diverse group of species and some of its characteristic traits.


Asunto(s)
Drosophilidae/clasificación , Hongos/fisiología , Animales , Teorema de Bayes , Evolución Biológica , Cruzamiento , Núcleo Celular/genética , Dopa-Decarboxilasa/clasificación , Dopa-Decarboxilasa/genética , Drosophila/genética , Drosophilidae/genética , Drosophilidae/crecimiento & desarrollo , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Mitocondrias/genética , Filogenia
2.
Rev. epidemiol. controle infecç ; 9(1): 100-102, 2019. ilus
Artículo en Inglés | LILACS | ID: biblio-1021422

RESUMEN

Background and Objectives: Helicobacter pylori is linked to gastroduodenal pathologies. To determine the frequency and potential risk factors of the H. pylori infection. Material and methods: A cross-sectional study was conducted, including 227 patients, submitted to upper gastrointestinal endoscopy. A questionnaire was applied to the patients, before endoscopy. The biopsy specimens were obtained from the antrum and gastric body for histology and PCR. The chi-square test was used for the categorical data analysis. P-values<0.05 were considered statistically significant.Results: 66.5% patients were positive for H. pylori. Based on the questionnaires applied to the patients, it was verified that marital status, smoking, alcohol consumption, toilet, education level and monthly family income had no significant association with the presence of H. pylori (p>0.05). However, we observed a significant association between the number of persons per household and presence of H. pylori (p=0.04). A statistically significant relation also was found between H. pylori and the patient's age (p=0.04) and between the histological and endoscopic diagnoses and the H. pylori infection (p≤0.01). Conclusions: We found a significant relation between household crowding and presence of H. pylori, which seems facilitate the person-to-person transmission H. pylori within families. Our results also suggest a cohort phenomenon. The increase in the frequency of H. pylori infection according to age may be due the acquisition of bacterium predominantly in childhood, when the sanitary conditions were deficient, and not during adulthood. Once acquired and untreated, the persistent H. pylori infection might have led to the development of severe gastroduodenal diseases.(AU)


Asunto(s)
Humanos , Helicobacter pylori , Infecciones
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