Anesthesia or seizure-like behavior? The effects of two Amazonian plants, Acmella oleracea and Piper alatabaccum in zebrafish (Danio rerio).

Currently, available fish anesthetics can produce important side effects, including respiratory arrest and distress. Easy-to-implement alternatives with low toxicity are needed to ensure fish health as well as to help artisanal fisheries and fish sellers in handling and transporting fishes, and native plants seems to be the best alternative. We aimed to implement an anesthetic protocol using crude ethanolic extracts from flowers and leaves of two Amazonian plants, the Acmella oleracea and Piper alatabaccum. We first tested the extracts for anesthesia, using the zebrafish as model. Even though in some treatments the animals apparently entered deep anesthesia, many of them presented aberrant behaviors and even died. Thus, we performed new experiments testing the extracts effects on seizure-like behaviors of the fish. Only the leaf extract of A. oleracea has potential effects for fish anesthesia. Both the flower extract from this plant and the leaf extract from P. alatabaccum induced seizure-like behavior in the animals. In conclusion, besides bringing a possible new anesthetic protocol for fish, our work draws attention for the neurotoxic effects the anesthetic solutions may cause, since several studies defend other Piper species as anesthetic for fish and A. oleracea flowers' extract was already pointed as fish anesthetic.

Lesão e reconstrução do LCA: uma revisão biomecânica e do controle motor / Lesion and reconstruction of ACL: biomechanical and motor control review

Neste artigo e apresntada uma revisao de literatura sobre as principais modificacoes e adaptacoes biomecanicas e dos mecanismos de controle motor decorrentes de lesao no ligamento cruzado anterior (LCA) e/ou de sua reconstrucao cirurgica. Inicialmente, sao descritas a funcao mecanica do LCA e sua anatomia. Em seguida, e disutido como essa funcionalidade e modificada do ponto de vista dos fatores neuromusculares na presenca de lesao e/ou reconstrucao do LCA. Sao enfatizadas as modificacoes proprioceptivas nas respostas reflexas e na ordem de recrutamento e a quantidade e o padrao de atividade da musculatura do membro inferior. Essas mudancas nos padroes eletromiograficos sao debatidas com base nas modificacoes biomecanicas causadas pela lesao do LCA. Em especial e mostrado como as mudancas nos padroes eletromiograficos podem explicar as alteracoes observadas nos movimentos rotacionais e translacionais do joelho nessa populacao. Finalmente, e discutido o efeito dessas mudancas na cinematica dos movimentos nos padroes dos torques musculares na articulacao do joelho