RESUMO
Harmful algal blooms (HABs) are recurrent in the NW Patagonia fjords system and their frequency has increased over the last few decades. Outbreaks of HAB species such as Alexandrium catenella, a causal agent of paralytic shellfish poisoning, and Protoceratium reticulatum, a yessotoxins producer, have raised considerable concern due to their adverse socioeconomic consequences. Monitoring programs have mainly focused on their planktonic stages, but since these species produce benthic resting cysts, the factors influencing cyst distributions are increasingly gaining recognition as potentially important to HAB recurrence in some regions. Still, a holistic understanding of the physico-chemical conditions influencing cyst distribution in this region is lacking, especially as it relates to seasonal changes in drivers of cyst distributions, as the characteristics that favor cyst preservation in the sediment may change through the seasons. In this study, we analyzed the physico-chemical properties of the sediment (temperature, pH, redox potential) and measured the bottom dissolved oxygen levels in a "hotspot" area of southern Chile, sampling during the spring and summer as well as the fall and winter, to determine the role these factors may play as modulators of dinoflagellate cyst distribution, and specifically for the cysts of A. catenella and P. reticulatum. A permutational analysis of variance (PERMANOVA) showed the significant effect of sediment redox conditions in explaining the differences in the cyst assemblages between spring-summer and fall-winter periods (seasonality). In a generalized linear model (GLM), sediment redox potential and pH were associated with the highest abundances of A. catenella resting cysts in the spring-summer, however it was sediment temperature that most explained the distribution of A. catenella in the fall-winter. For P. reticulatum, only spring-summer sediment redox potential and temperature explained the variation in cyst abundances. The implications of environmental (physico-chemical) seasonality for the resting cysts dynamics of both species are discussed.
Assuntos
Cistos , Dinoflagellida , Intoxicação por Frutos do Mar , Estuários , Proliferação Nociva de Algas , Humanos , Estações do AnoRESUMO
La asociación entre Enfermedad Periodontal y Disfunción Eréctil se ha estudiado limitadamente. Sin embargo, hoy en día los estudios disponibles han reportado una posible asociación en base a factores de riesgo compartidos entre ambas patologías, pero fundamentalmente se atribuye la asociación al fenómeno de disfunción endotelial que se vincula con ambas enfermedades. Se ha propuesto que la enfermedad periodontal crónica puede inducir una respuesta inflamatoria sistémica que resulta en el deterioro de las condiciones fisiológicas y bioquímicas del endotelio generando disfunción endotelial. Por otro lado, se reconoce a la disfunción eréctil como una enfermedad de origen multifactorial, en la que prevalece la condición vasculogénica como el factor etiológico más frecuente, esto atribuido a un defecto vascular (disfunción endotelial). Es así como el punto de enlace más fuerte es la alteración de la función vascular, que sin duda demuestra argumento sólido de asociación entre las dos enfermedades. El objetivo de esta revisión bibliográfica es informar sobre los posibles mecanismos de asociación entre enfermedad periodontal y disfunción eréctil, enfocándose en el proceso de disfunción endotelial como el principal vínculo existente.(au)
The association between periodontal disease and erectile dysfunction has not been sufficiently studied. However, recent studies have reported a possible link based on mutually shared risks factors between both pathologies, but the association is fundamentally attributed to endothelial dysfunction, phenomenon that is related to both diseases. It has been suggested that chronic periodontal disease can induce systemic inflammatory response that results in deterioration of the physiological and biochemical conditions of the endothelium causing endothelial dysfunction. On the other hand, erectile dysfunction is a multifactorial disease, but the vasculogenic factor is considered as the most frequent one, attributed to a vascular defect (endothelial dysfunction). So, the strongest link is the vascular function alteration, which undoubtedly demonstrates demonstrates a solid argument of association between both diseases. The objective of this literature review is to report the possible mechanisms of association between periodontal disease and erectile dysfunction, focusing mainly on endothelial dysfunction as the main existing link.(au)