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Pedrera L.,University of Habana | Gomide A.B.,University of Sao Paulo | Gomide A.B.,Centro Universitario Padre Anchieta | Sanchez R.E.,University of Habana | And 7 more authors.
Langmuir | Year: 2015

Sticholysin I (St I) is a pore-forming toxin (PFT) produced by the Caribbean Sea anemone Stichodactyla helianthus belonging to the actinoporin protein family, a unique class of eukaryotic PFT. As for actinoporins, it has been proposed that the presence of cholesterol (Chol) and the coexistence of lipid phases increase binding to the target membrane and pore-forming ability. However, little is known about the role of membrane structure and dynamics (phase state, fluidity, and the presence of lipid domains) on the activity of actinoporins or which regions of the membrane are the most favorable for protein insertion, oligomerization, and eventually pore formation. To gain insight into the role of membrane properties on the functional activity of St I, we studied its binding to monolayers and vesicles of phosphatidylcholine (PC), sphingomyelin (SM), and sterols inducing (ergosterol -Erg and cholesterol -Chol) or not (cholestenone - Cln) membrane phase segregation in liquid ordered (Lo) and liquid disordered (Ld) domains. This study revealed that St I binds and permeabilizes with higher efficiency sterol-containing membranes independently of their ability to form domains. We discuss the results in terms of the relevance of different membrane properties for the actinoporins mechanism of action, namely, molecular heterogeneity, specially potentiated in membranes with sterols inducers of phase separation (Chol or Erg) or Cln, a sterol noninducer of phase separation but with a high propensity to induce nonlamellar phase. The role of the Ld phase is pointed out as the most suitable platform for pore formation. In this regard, such regions in Chol-containing membranes seem to be the most favored due to its increased fluidity; this property promotes toxin insertion, diffusion, and oligomerization leading to pore formation. © 2015 American Chemical Society.

Perandini L.A.,State University Londrina | Perandini L.A.,Centro Universitario Padre Anchieta | Siqueira-Pereira T.A.,State University Londrina | Okuno N.M.,State University Londrina | And 3 more authors.
Revista Brasileira de Cineantropometria e Desempenho Humano | Year: 2010

The aim of this study was to evaluate the relationship between vagal withdrawal and reactivation indices and maximal running velocity (Vmax) in taekwondo athletes. Eleven elite taekwondo athletes (seven men: 23.7±2.2 years, 72.4±7.0 kg, 178.8±7.5 cm, 51.9±2.9 ml.kg-1.min-1, and four women: 18.8±1.5 years, 61.8±1.8 kg, 168.0±4.4 cm, 41.6±2.4 ml.kg-1.min-1) performed a graded exercise test until exhaustion, with the last complete stage performed corresponding to Vmax. Heart rate variability (HRV) parameters were calculated at 1-minute intervals until 85% of maximum HR and plotted against time for the estimation of vagal withdrawal indices (τ, amplitude (A) and area under the curve (AUC)). Vagal reactivation indices were determined based on HR recovery during the first 60 s (HRR60s) and negative reciprocal of the slope of the regression line obtained during the first 30 s of HRR (T30). The vagal withdrawal parameters A and AUC were moderately and significantly correlated with Vmax (r = 0.61-0.71, P < 0.05), whereas τ presented a low correlation (r = 0.22-0.40, P > 0.05). T30 and HRR60s were also significantly correlated with Vmax (r = -0.77 and 0.64, P < 0.05, respectively). The present results showed that vagal withdrawal (A and AUC) and vagal reactivation (T30 and HRR60s) indices were significantly correlated with Vmax, suggesting that these indices can be used for the evaluation and monitoring of aerobic fitness in taekwondo athletes.

Perandini L.A.,State University Londrina | Perandini L.A.,Centro Universitario Padre Anchieta | Siqueira-Pereira T.A.,State University Londrina | Okuno N.M.,State University Londrina | And 2 more authors.
Science and Sports | Year: 2012

Objective: The purposes of this study were to: verify whether rating of perceived exertion (RPE) can be used to determine the training load, using heart rate (HR) and blood lactate concentration ([BLa -]) as the criteria measurements, and determine the association and agreement of training intensity distribution based on RPE and [BLa -] responses in taekwondo training. Methods: Eleven elite taekwondo athletes performed a progressive test, in order to estimate maximal HR, and two training sessions. Twenty-two training loads were quantified based on RPE (session-RPE), HR and [BLa -] responses. The training intensity distribution was performed using RPE and [BLa -] responses. The level of statistical significance was set at P<0.05. Results: All correlations between session-RPE with HR and [BLa -] methods were statistically significant (r=0.52-0.71, P<0.05). The association between proportions of training intensity distribution based on RPE and [BLa -] responses were significant (P>0.05) with a high agreement (k=0.71). Conclusion: Taekwondo coaches can use RPE to quantify training loads and training intensity distribution in order to better plan and assist training program.

Tosetto T.,Federal University of Sao Carlos | Orsi F.G.,Centro Universitario Padre Anchieta
Work | Year: 2012

Among the indicators of Decent Work in Brazil, the one referring to the "Safe Working Environment" was the only which had no improvement in the time series analyzed by the International Labor Organisation. There is an increased number of accidents with significant economic and social impacts. Given that many of these accidents involve the hands and cause functional sequels, this paper presents an integration between the approaches of Hand Therapy and Ergonomics in order to facilitate the process of rehabilitation and reintegration, as well as acting to prevent further accidents, thus contributing to the promotion of Decent Work in the country, particularly with regard to safety and health at work and equal opportunities. © 2012 - IOS Press and the authors. All rights reserved.

Morato M.P.,University of Campinas | Giglio S.S.,University of Campinas | Giglio S.S.,Nove de Julho University | Gomes M.S.P.,University of Campinas | And 2 more authors.
Motriz. Revista de Educacao Fisica | Year: 2011

This paper objectives to investigate the idol role in the construction of the football phenomenon in Brazil. For that, ex-football players, professional football players and football 5-a-side players were interviewed. The data analysis emphasized four categories: Creation, Diffusion, Idolatry and Roles. To analyze and make inferences from the data, the Enunciation Analysis, one of the Contend Analysis technique was used. The construction of idols was dependent on the appreciation of great achievements and creating bonds. The achievements are dependent on the categories time and space, giving an "expiration date" to idolatry and providing a cyclic renewal of idols. The stronger the relationship of the triad player-club-fan, the deeper the bonds will be. The achievements are "shown" in the media and if the bonds are well established, the image of the idol will be exalted and valued, nurturing and motivating the passion of the fans and cultivating the dream of being a football player in the social imaginary.

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