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Almeida, L. G.

Publications and source records attributed to Almeida, L. G..

2 recordsLinked to original sources

Anthropometric and functional profiles of elite athletes from different categories at ABADA Capoeira World Championship

This study aimed to characterize the anthropometric and functional profiles of 50 male elite competitors at the 2017 Capoeira World Championship organized by ABADA Capoeira School in the city of Rio de Janeiro. The competitors were divided into different weight categories: lightweight (VIOLA, [&le;]76.9 kg; n = 15), intermediate weight (MEDIO, 77.0-85.9 kg; n = 25), and heavyweight (GUNGA, [&ge;]86.0 kg; n = 10). Two evaluation batteries were performed: 1) anthropometry and somatotype determination and 2) functional performance on push-up, sit-up, and sit-and-reach tests; quadrant jump test (QJT); squat jump (SJ); and countermovement jump (CMJ). Results reveal that the mesomorphic component of the somatotype differed between the GUNGA subgroup and other groups (F[2,47] = 7.617; p = 0.001), while ectomorphy differed between the VIOLA and GUNGA subgroups (F[2,47] = 3.899; p = 0.027). The \"endo-mesomorph\" classification predominated in the three investigated categories. For functional performance, there was a difference in QJT between the VIOLA and GUNGA subgroups (F[2,47] = 4.299; p = 0.019). The endomorphism had a negative correlation (p < 0.01) with the performance in the sit-up (r = -0.51), push -up (r = -0.39), SJ (r = -0.45), and CMJ (r = -0.49). We concluded that at the international level, male elite competitors show predominance in the mesomorphic component of the somatotype. Furthermore, the endomorphic component correlated inversely with functional performance in trunk and upper limb resistance tests and lower limb explosive strength tests. These results can help coaches in targeting specific training programs for Capoeira athletes who aim for a high competitive level.

physiology

Continuous rearrangement of the postsynaptic gephyrin scaffolding domain: a super-resolution quantified and energetic approach

Synaptic function and plasticity requires a delicate balance between overall structural stability and the continuous rearrangement of the components that make up the presynaptic active zone and the postsynaptic density (PSD). Photoactivated localization microscopy (PALM) has provided a detailed view of the nanoscopic structure and organization of some of these synaptic elements. Still lacking, are tools to address the morphing and stability of such complexes at super-resolution. We describe an approach to quantify morphological changes and energetic states of multimolecular assemblies over time. With this method, we studied the scaffold protein gephyrin, which forms postsynaptic clusters that play a key role in the stabilization of receptors at inhibitory synapses. Postsynaptic gephyrin clusters exhibit an internal microstructure composed of nanodomains. We found, that within the PSD, gephyrin molecules continuously undergo spatial reorganization. This dynamic behavior depends on neuronal activity and cytoskeleton integrity. The proposed approach also allowed access to the effective energy responsible for the tenacity of the PSD despite molecular instability.\n\nSignificant statementSuper-resolution microscopy has become an important tool for the study of biological systems, allowing detailed, nano-scale structural reconstruction, single molecule tracking, particle counting, and interaction studies. However, quantification tools that take full advantage of the information provided by this technology are still lacking. We describe a novel quantification method to obtain information related to the size, directionality, dynamics, and stability of clustered structures from super-resolution microscopy. With this method, we studied the stability of gephyrin clusters, the main inhibitory scaffold protein. We found that gephyrin molecules continuously undergo reorganization based on neuronal activity and changes in the cytoskeleton.

biophysics