RESUMO
Sponges thrive in marine benthic communities due to their specific and diverse chemical arsenal against predators and competitors. Yet, some animals specifically overcome these defences and use sponges as food and home. Most research on sponge chemical ecology has characterised crude extracts and investigated defences against generalist predators like fish. Consequently, we know little about chemical dynamics in the tissue and responses to specialist grazers. Here, we studied the response of the sponge Aplysina aerophoba to grazing by the opisthobranch Tylodina perversa, in comparison to mechanical damage, at the cellular (via microscopy) and chemical level (via matrix-assisted laser desorption/ionization imaging mass spectrometry, MALDI-imaging MS). We characterised the distribution of two major brominated alkaloids in A. aerophoba, aerophobin-2 and aeroplysinin-1, and identified a generalised wounding response that was similar in both wounding treatments: (i) brominated compound-carrying cells (spherulous cells) accumulated at the wound and (ii) secondary metabolites reallocated to the sponge surface. Upon mechanical damage, the wound turned dark due to oxidised compounds, causing T. perversa deterrence. During grazing, T. perversa's way of feeding prevented oxidation. Thus, the sponge has not evolved a specific response to this specialist predator, but rather relies on rapid regeneration and flexible allocation of constitutive defences.
Assuntos
Alcaloides/metabolismo , Gastrópodes/metabolismo , Poríferos/metabolismo , AnimaisRESUMO
Objetivo: desarrollar y aplicar un manual para evaluar los procesos de deglución y rendimiento masticatorio, dirigido a estudiantes y profesionales de odontología. Método: se realizó un estudio con enfoque cuali-cuantitativo, a partir de dos técnicas de recolección de información: documental para reunir información de los procedimientos y observacional para la aplicación del manual. Los métodos seleccionados fueron el rendimiento masticatorio (Albert T) y de deglución (Técnica Payne); el diseño se esbozó según la metodología para mejorar la calidad de los procesos y una guía técnica de elaboración de manuales de procedimientos en salud. Así, el manual cuenta con introducción, antecedentes históricos, alcance y objetivo, flujograma, descripción de procedimientos de evaluación de la deglución, del rendimiento masticatorio y bibliografía. Este fue aplicado en 27 pacientes de la clínica de ortodoncia, a quienes se les diagnosticó deglución atípica, y se midió el rendimiento masticatorio para conocer la mediana de tamaño de partícula (MTP) de cada individuo. Resultados: el manual se realizó basándose en dos procedimientos, uno con el diagnóstico de deglución y otro con rendimiento masticatorio. Este último fue aplicado por dos estudiantes investigadores a una muestra de 27 pacientes, cuyo resultado fue una mediana de tamaño total de partícula de MTP = 5.35 mm2. Hubo una diferencia estadísticamente significativa entre sexos (MTP en hombres: 6,0 mm2 y mujeres 5.1 mm2) siendo las mujeres quienes presentaron mejor desempeño masticatorio. Conclusión: al aplicar el manual, los estudiantes evaluaron el rendimiento masticatorio y la deglución, con lo cual lograron resultados medibles, aplicables y reproducibles.
Objective: To apply a manual to evaluate swallowing and chewing performance aimed at dental students and professionals. Method: A study was carried out with a qualitative-quantitative approach developing two information gathering techniques: documentary to gather information on procedures and observational in the application of the manual. The methods of chewing performance (Albert T) and swallowing (Payne Technique) were selected; the design was outlined according to the methodology to improve the quality of the processes and a technical guide for the elaboration of manuals of health procedures; in the development phase, the thematic units were created and the manual was prepared with: cover, back cover, authors, introduction, historical background, scope and objective, flow chart, description of swallowing evaluation procedures, chewing performance and bibliography; this was applied to 27 patients from the orthodontic clinic, who were diagnosed with atypical swallowing, and the masticatory performance was measured to determine the median particle size (MTP) of each individual evaluated. Results: The manual was made based on two procedures, one with swallowing diagnosis and the other with masticatory performance, which was applied by two student researchers to a sample of 27 patients, yielding a median total particle size of MTP = 5.35 mm2. There was a statistically significant difference between the sexes (MTP in men: 6.0 mm2 and women 5.1 mm2), with women presenting the best masticatory performance Conclusion: when applying the manual, the students evaluated the chewing performance and swallowing, achieving measurable, applicable and reproducible.