ABSTRACT
Terror birds (Aves, Phorusrhacidae) comprise the most outstanding group of South American Cenozoic avifauna, and have been considered dominant predators. Terrestrial habits were inferred using the reduction of their forelimbs and high body mass. Phorusrhacids were considered functionally tridactyl with three relatively short digits II-IV and a small, elevated digit I. The function of the ungual phalanges of digit II have been debated, including the utility of the ungual for retention or stabbing of prey. Incomplete or lack of preservation of foot bones have hampered understanding of the evolution and diversification of Phorusrhacidae. Here we show the first known and well-preserved footprints of Phorusrhacidae with a didactyl posture, which are named Rionegrina pozosaladensis igen. et isp. nov. These footprints yield unprecedented information on the locomotor habits of the group. The finding implies that medium-sized, Late Miocene (~ 8 Ma) phorusrhacids developed strong cursorial adaptations; achieved through reduction of digit II, raised metatarso-phalangeal pad, main body support in a large and thick digit III, and digit IV as outrigger. Raised and long claw of digit II was probably used in pining of prey. Phorusrhacid footprints differ from the Early Cretaceous didactyl footprints of deinonychosaurian dinosaur affinity by its larger size and strong mesaxony.
Subject(s)
Dinosaurs , Fossils , Animals , Dinosaurs/anatomy & histology , Birds , Forelimb , Posture , Biological EvolutionABSTRACT
The ageing of population is increasing, and a great percentage of these patients wear removable prostheses, and can suffer denture stomatitis, a condition that has been associated with candidiasis. Aims: To evaluate in vitro the effectiveness of Copper Sulfate against Candida albicans in samples of heat-polymerized acrylic resin, compared to nystatin, sodium hypochlorite and chlorhexidine. Materials and Methods: Initially, the minimum inhibitory concentration (MIC) of copper sulfate for Candida albicans was determined by microdilution. Then, 54 resin samples were divided into 6 treatment groups corresponding to Nystatin 100.000 UI, Sodium Hypochlorite 0.5%, chlorhexidine 0.12%, Copper Sulfate 4.7µg/ml, Copper Sulfate 9.4µg/ml and physiological saline solution, in which samples were submerged for 6 hours. Resin samples were then washed and cultured on solid media at 37°C for 72 hours. The number of colony-forming units was determined using a Quebec colony counter. The statistical analysis was performed using the Kruskal-Wallis test and the Mann-Whitney U test. Results: Copper sulfate at a concentration of 9.4µg/ml presented a similar effectiveness as the other control products regarding the reduction in the number of colonies of Candida albicans post-treatment. Conclusion: The effectiveness of copper sulfate against Candida albicans on acrylic resin was similar to that of nystatin, sodium hypochlorite and chlorhexidine.
En las últimas décadas se ha observado un aumento de la población de adultos mayores, de los cuales un gran porcentaje es portador de prótesis removible, y dos tercios pueden sufrir estomatitis subprotésica, enfermedad que es asociada a infecciones como candidiasis. Objetivo: Evaluar la efectividad antimicótica in vitro del sulfato de cobre en placas de resinas acrílicas de termocurado inoculadas con Candida albicans, frente a Nistatina, Hipoclorito de Sodio y Clorhexidina. Material y Métodos: Inicialmente, y mediante microdilución del sulfato de cobre, se determinó la concentración mínima inhibitoria (CMI) para Candida albicans. En la fase experimental, 54 muestras de resina se dividieron en 6 grupos correspondientes a Nistatina 100.000 UI, Hipoclorito 0.5%, Clorhexidina 0.12%, Sulfato de Cu 4.7µg/ml, Sufato de Cu 9.4 µg/ml y suero fisiológico. Las muestras fueron sumergidas en estos agentes por 6 horas, para posteriormente ser lavadas y cultivada en medios solidos a 37°C por 72 horas. Luego se realizó el conteo de unidades formadoras de colonias mediante contador tipo Quebec. El análisis estadístico se realizó mediante la prueba de Kruskal-Wallis y la prueba U de Mann-Whitney. Resultado: El sulfato de cobre a una concentración de 9.4µg/ ml presentó una efectividad similar a los otros productos, en la reducción de colonias de Candida albicans. Conclusión: La efectividad del sulfato de cobre contra Candida albicans fue semejante a la de Nistatina, Hipoclorito y Clorhexidina.
