RESUMO
In recent years, advances in analyses of the sperm morphology and genetics of Perumytilus purpuratus have allowed to two evolutionary scenarios for this mussel to be suggested: (1) the scenario of cryptic species and (2) the scenario of incipient or in progress speciation. For a better understanding of the evolutionary history of P. purpuratus, we performed extensive sampling along a latitudinal gradient of ca. 7180 km of coastline-from the Southern Pacific Ocean to the Atlantic Ocean-and we delved deeper into the sperm morphology of P. purpuratus, exploring its association with the phylogeny and population genetics to determine whether the variability in sperm traits between the northern and southern regions was a signal of cryptic or incipient species. Overall, our results showed that sperm sizes were strongly correlated with the genetic structure in males of P. purpuratus. We identified at 37° S on the Pacific coast a coincident break of both sperm size and genetic disruption that can be explained by historical events and postglacial recolonization as causal phenomena for the observed divergences. Furthermore, evidence of genetic admixture between lineages was found at 38° S, suggesting the presence of an introgressive hybridization zone and incomplete reproductive isolation in an in fraganti or incipient speciation process.
RESUMO
Objetivo: Determinar si difieren los valores espirométricos evaluados en niños sanos de 7- 8 años provenientes de comunas con niveles históricos de alta versus baja contaminación atmosférica en Chile. Materiales y métodos: Estudio descriptivo, no experimental, exploratorio y transversal y ex post facto causa y efecto. Se realizaron en total 261 encuestas de salud respiratoria y calificaron, según criterios de inclusión, 110 niños sanos de 7 y 8 años (55 niños en cada comuna). Se realizaron exámenes espirométricos: Con espirómetro de turbina SPIROBANK G, considerando variables vefi, FEF25-75, pef y cvf. La obesidad, actividad física, contaminación intramuros por calefacción y exposición a humo de tabaco también fueron descritas. Resultados: Las variables espirométricas analizadas vefi y FEF25-75 mostraron diferencias significativas (p<0.05) y pef mostró diferencias altamente significativas (p <0.005) según localidad, es decir, que la media de estas variables en Los Andes, comuna agroindustrial con baja contaminación atmosférica, es mayor que la de Cerro Navia, comuna con altos niveles de contaminación del aire. En la variable pef se encontró, además, significancia entre género. La cvf no presentó diferencia entre comunas. Conclusiones: Los niños sanos de 7 y 8 años que habitan en comunas donde la exposición a contaminación atmosférica es alta presentan una menor función pulmonar comparada con los niños sanos, de similares características, que habitan en comunas con bajos niveles de contaminación atmosférica. Existen otros factores que podrían influir en el detrimento de la función pulmonar y que en este estudio fueron descritos como factores confundentes.
Objective: To determine if spirometric values evaluated in healthy children aged 7-8 years differ from one locality with high historical levels of air pollution versus a locality with lower levels of air pollution in Chile. Materials and methods: Descriptive, non-experimental, exploratory and ex post facto cross and cause and effect. In total 261 surveys were performed of respiratory health and rated according to inclusion criteria, 110 healthy children between 7 and 8 years (55 children in each commune). Spirometric tests were performed, considering variables FEV1, FEF25-75, PEF and FVC. Obesity, physical activity, indoor pollution from heating and snuff smoke exposure were also described. Results: The analyzed spirometry FEV1 and FEF25-75 showed significant differences (p <0.05) and PEF showed high significant differences (p<0.005) by location, that it to say, the average of these variables in the locality of Los Andes, commune with low air pollution is greater than Cerro Navia, a commune with high levels of air pollution. Variable in PEF was found also between gender significance. FVC showed no difference between communities. Conclusions: Healthy children of 7 and 8 who live in the locality where exposure of air pollution is high, have lower lung functions compared with healthy children with similar characteristics who live in communities with lower levels of air pollution. There are other factors that could influence the detriment of pulmonary function, in this study were described as confounding factors.