RESUMO: Alelopatia é definida como a capacidade que determinadas plantas e microrganismos têm de interferir no metabolismo de outras espécies, por meio de substâncias liberadas no ambiente, podendo ser uma alternativa de combate às plantas daninhas e doenças. Nesse contexto, este estudo teve por objetivos avaliar o potencial alelopático e identificar os grupos de metabólitos secundários de Paspalum maritimum Trind. As espécies Lactuca sativa, Digitaria insularis, Emilia coccinea e Portulaca oleracea foram utilizadas como plantas receptoras. Para avaliar o potencial alelopático, foram obtidos o extrato etanólico da parte aérea e radicular da espécie doadora. Os efeitos potencialmente alelopáticos foram avaliados por meio de testes de germinação, índice de velocidade de germinação e crescimento inicial de plântulas. Foi realizada também a análise fitoquímica do extrato, para identificar os metabólitos secundários. O extrato etanólico, de ambas as partes da planta, causaram efeito alelopático nas espécies receptoras. Foi detectada, na fração mais ativa da parte aérea de P. maritimum, a presença de taninos condensados, chalconas e auronas, flavononas, esteroides e saponinas.

ABSTRACT: Allelopathy is defined as the ability of certain plants and microorganisms to interfere with the metabolism of other species through substances released into the environment, being an alternative to control weeds and diseases. In this context, this study aimed to evaluate the allelopathic potential and identify groups of secondary metabolites of Paspalum maritimum Trind. The species Lactuca sativa, Digitaria insularis, Emilia coccinea, and Portulaca oleracea were used as recipient plants. The ethanolic extract was obtained from shoot and root of donor species to evaluate the allelopathic potential. Potentially allelopathic effects were evaluated by means of germination tests, germination speed index, and initial seedling growth. A phytochemical analysis of the extract was also performed to identify the secondary metabolites. The ethanolic extract from both plant parts had an allelopathic effect on recipient species. The presence of condensed tannins, chalcones and aurones, flavonones, steroids, and saponins were detected in the most active fraction of the shoot of P. maritimum.

Simultaneous measurements of EEG-functional magnetic resonance imaging (fMRI) combine the high temporal resolution of EEG with the distinctive spatial resolution of fMRI. The purpose of this EEG-fMRI study was to search for hemodynamic responses (blood oxygen level-dependent - BOLD responses) associated with interictal activity in a case of right mesial temporal lobe epilepsy before and after a successful selective amygdalohippocampectomy. Therefore, the study found the epileptogenic source by this noninvasive imaging technique and compared the results after removing the atrophied hippocampus. Additionally, the present study investigated the effectiveness of two different ways of localizing epileptiform spike sources, i.e., BOLD contrast and independent component analysis dipole model, by comparing their respective outcomes to the resected epileptogenic region. Our findings suggested a right hippocampus induction of the large interictal activity in the left hemisphere. Although almost a quarter of the dipoles were found near the right hippocampus region, dipole modeling resulted in a widespread distribution, making EEG analysis too weak to precisely determine by itself the source localization even by a sophisticated method of analysis such as independent component analysis. On the other hand, the combined EEG-fMRI technique made it possible to highlight the epileptogenic foci quite efficiently.