RESUMEN
DNA repair pathways, cell cycle checkpoints, and redox protection systems are essential factors for securing genomic stability. The aim of the present study was to analyze the effect of Ilex paraguariensis (Ip) infusion and one of its polyphenolic components rutin on cellular and molecular damage induced by ionizing radiation. Ip is a beverage drank by most inhabitants of Argentina, Paraguay, Southern Brazil, and Uruguay. The yeast Saccharomyces cerevisiae (SC7Klys 2-3) was used as the eukaryotic model. Exponentially growing cells were exposed to gamma rays (γ) in the presence or absence of Ip or rutin. The concentrations used simulated those found in the habitual infusion. Surviving fractions, mutation frequency, and DNA double-strand breaks (DSB) were determined after treatments. A significant increase in surviving fractions after gamma irradiation was observed following combined exposure to γ+R, or γ+Ip. Upon these concomitant treatments, mutation and DSB frequency decreased significantly. In the mutant strain deficient in MEC1, a significant increase in γ sensitivity and a low effect of rutin on γ-induced chromosomal fragmentation was observed. Results were interpreted in the framework of a model of interaction between radiation-induced free radicals, DNA repair pathways, and checkpoint controls, where the DNA damage that induced activation of MEC1 nodal point of the network could be modulated by Ip components including rutin. Furthermore, ionizing radiation-induced redox cascades can be interrupted by rutin potential and other protectors contained in Ip.
Asunto(s)
Antimutagênicos/farmacología , Ilex paraguariensis/química , Extractos Vegetales/farmacología , Rutina/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Cromatografía Liquida , Roturas del ADN de Doble Cadena , Reparación del ADN , ADN de Hongos/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Rayos gamma , Espectrometría de Masas , Mutagénesis , Tasa de Mutación , Protección Radiológica/métodos , Reproducibilidad de los ResultadosRESUMEN
DNA repair pathways, cell cycle checkpoints, and redox protection systems are essential factors for securing genomic stability. The aim of the present study was to analyze the effect of Ilex paraguariensis (Ip) infusion and one of its polyphenolic components rutin on cellular and molecular damage induced by ionizing radiation. Ip is a beverage drank by most inhabitants of Argentina, Paraguay, Southern Brazil, and Uruguay. The yeast Saccharomyces cerevisiae (SC7Klys 2-3) was used as the eukaryotic model. Exponentially growing cells were exposed to gamma rays (γ) in the presence or absence of Ip or rutin. The concentrations used simulated those found in the habitual infusion. Surviving fractions, mutation frequency, and DNA double-strand breaks (DSB) were determined after treatments. A significant increase in surviving fractions after gamma irradiation was observed following combined exposure to γ+R, or γ+Ip. Upon these concomitant treatments, mutation and DSB frequency decreased significantly. In the mutant strain deficient in MEC1, a significant increase in γ sensitivity and a low effect of rutin on γ-induced chromosomal fragmentation was observed. Results were interpreted in the framework of a model of interaction between radiation-induced free radicals, DNA repair pathways, and checkpoint controls, where the DNA damage that induced activation of MEC1 nodal point of the network could be modulated by Ip components including rutin. Furthermore, ionizing radiation-induced redox cascades can be interrupted by rutin potential and other protectors contained in Ip.
Asunto(s)
Rutina/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/efectos de la radiación , Extractos Vegetales/farmacología , Antimutagênicos/farmacología , Ilex paraguariensis/química , Protección Radiológica/métodos , Espectrometría de Masas , ADN de Hongos/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Reproducibilidad de los Resultados , Cromatografía Liquida , Mutagénesis , Reparación del ADN , Relación Dosis-Respuesta en la Radiación , Roturas del ADN de Doble Cadena , Tasa de Mutación , Rayos gammaRESUMEN
Ichthyofauna distribution and habitat characteristics of Thalassia beds in the Grand Cul-de-Sac marin lagoon in Guadeloupe were studied during a one-year survey. Environmental variables (9) were measured monthly in ten sites along with collection of fish communities. The environmental data set, analysed alone through between-within group 'principal component analysis' (PCA), exhibited a significant spatial and temporal variability. The fish data set, however, presented only a significant spatial structure, stable over the year. Given the lack of temporal variability in fish distribution, a 'between-site co-structure analysis' (BSCA) was used to compare the faunistic and environmental structures in space. The co-inertia structure was reduced to one axis representing a strong coast-reef gradient, the major common phenomena to both data sets. Environment and fish distribution allowed to distinguish sites directly under mangrove influence (characterised by high seagrasses, high concentration of chlorophyll a and high densities of zooplankton), to sites under reef influence (with short but dense seagrasses, clear water, and poor nutriments). For that purposes, the BSCA summarised efficiently what in common the fauna spatial structure and the environment spatial structure may present.
Asunto(s)
Ecosistema , Ambiente , Peces , Magnoliopsida , Clima Tropical , Animales , Biomasa , Clorofila/análisis , Guadalupe , Concentración de Iones de Hidrógeno , Océanos y Mares , Plancton , Silicatos/análisis , TemperaturaRESUMEN
Molineus torulosus (Molin, 1861) parasite of Cebus spp. from South America is redescribed in Cebus apella and C. olivecaeus (new host) from French Guyana with emphasis on the synlophe. During the maturation process, the larvae dwelt in the cysts carved alongside the external part of the small intestine. The turn-out of the mature worms and the laid eggs depended on the tissular organisation of cyst walls as the inflammatory process waned and fibrosis progressed to seal the cystic lumen. Adult worms entwine themselves in the cysts, live there permanently as their presence has never been evidenced in the intestinal lumen. They copulated, laid eggs, degenerated and died once entrapped by the fibrotic process. Laid eggs released in the intestinal lumen through a narrow channel ensured the continuation of the developmental cycle. However, erratic migration was possible via the vascular channels surrounding the cysts.