The lipase from Rhizomucor miehei (RML) has been immobilized on chitosan-based hybrid (sodium alginate or carrageenan) matrices activated with glycidol (GLY), epichlorohydrin (EPI) or glutaraldehyde (GLU) groups. Then, the properties of the different biocatalysts have been evaluated and compared with the soluble RML. Thermal stability (at pH 7.0 and 60 °C) was significantly increased when compared to the soluble enzyme: 154-fold for chitosan 5.0% - GLU, 80-fold for chitosan 2.5% - carrageenan 2.5% - GLY and 93-fold for chitosan 2.5% - alginate 2.5% - EPI. The best biocatalyst preparation, which was 154-fold more stable than the soluble enzyme, was obtained when RML was immobilized on chitosan activated with glutaraldehyde 5.0% v/v. According to the results, it was concluded that RML immobilization on chitosan-based hybrid matrices using different chemistries greatly produced biocatalysts with different properties.

Resumo Contexto Os benefícios para a saúde decorrentes da prática regular de atividade física estão bem documentados. Entretanto, são raros os estudos associando essa prática ao comportamento sedentário e ao risco cardiovascular em adolescentes. Objetivos Pretende-se avaliar a prática de atividade física, o comportamento sedentário e a associação com o risco cardiovascular mensurado pelo escore Pathobiological Determinants of Atherosclerosis in Youth (PDAY). Métodos Estudo transversal desenvolvido nas escolas públicas estaduais de Campina Grande, PB, Brasil, com 576 adolescentes de 15 a 19 anos, incluindo variáveis socioeconômicas, demográficas, de estilo de vida e clínicas. Os dados foram coletados através de formulário validado, antropometria, aferição da pressão arterial e exames laboratoriais. Foram utilizadas medidas descritivas, teste do qui-quadrado de Pearson e regressão logística binomial. Trabalhou-se com o SPSS 22.0 se adotou intervalo de confiança de 95%. Resultados A idade média foi de 16,8 anos. A maioria dos adolescentes era do sexo feminino (66,8%), não branco (78.7%) e pertencente às classes C, D e (69,1%). Quanto ao sedentarismo e à insuficiência de atividade física, as prevalências foram de 78,1% e 60,2%, respectivamente. De acordo com o escore PDAY, 10,4% dos adolescentes apresentaram alto risco cardiovascular; 31,8% risco intermediário; e 57,8%, risco baixo. Verificou-se que PDAY esteve associado ao sexo e à adiposidade abdominal. Conclusões Ficou comprovado que adiposidade abdominal e sexo masculino representam importantes fatores de risco cardiovascular em adolescentes. Considerando-se a presença de um fator de risco modificável, medidas preventivas voltadas ao estilo de vida são essenciais.

Abstract Background The health benefits of regular physical activity are well documented. However, there are few studies associating this practice with sedentary behavior and cardiovascular risk in adolescents. Objectives To evaluate physical activity levels and sedentary behavior and their associations with cardiovascular risk using the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) score Methods A cross-sectional study carried out in state-owned public schools in Campina Grande, PB, Brazil, with 576 adolescents aged 15 to 19 years, investigating socioeconomic; demographic; lifestyle; and clinical variables. Data were collected using a validated form covering anthropometry data; blood pressure measurements; and laboratory tests. Data were analyzed using descriptive statistics, Pearson's chi-square test, and binomial logistic regression using SPSS 22.0 and adopting a 95% confidence interval. Results Mean age was 16.8 years. The majority of the adolescents were female (66.8%); non-white (78.7%); and belonged to socioeconomic classes C, D and E (69.1%). The prevalence rates of sedentary behavior and physical inactivity were 78.1% and 60.2%, respectively. According to the PDAY score, 10.4% of adolescents were at high cardiovascular risk and 31.8% and 57.8% were at intermediate risk and low risk, respectively. PDAY scores were associated with sex and abdominal adiposity. Conclusions It was found that abdominal fat and being male were important cardiovascular risk factors in adolescents. Considering that modifiable risk factors were present, preventive measures aimed at lifestyle changes are essential.