Evaluation of Internet addiction and the quality of life of Brazilian adolescents from public and private schools / Avaliação da dependência de Internet e qualidade de vida em adolescentes Brasileiros de escolas públicas e particulares

This study evaluated the profile of public and private high school students (N = 254, Mage = 15.1, SD = 1.3) in the city of São Paulo in relation to their Internet use patterns and quality of life. We used the Internet Addiction Test and the Pediatric Quality of Life Inventory. About 70% of the students had moderate Internet addiction. Those students from public school showed higher scores of Internet addiction (p < 0.001) than students from private schools. Regarding the quality of life, those from private school showed better scores regarding academic performance (p < 0.01) and worse scores in social aspect (p < 0.05). The data showed a strong association between Internet addiction and poor levels of quality of life, as observed in studies from other countries.

Este trabalho avaliou o perfil de estudantes em relação ao padrão de uso de Internet e qualidade de vida, tomando como sujeitos de pesquisa alunos do ensino médio (N = 254, Midade = 15,1, DP = 1,3) de escolas públicas e particulares da cidade de São Paulo. Utilizou-se o Teste de Dependência em Internet e o Pediatric Quality of Life Inventory. Aproximadamente 70% dos estudantes apresentaram dependência média de Internet. Estudantes de escola pública apresentaram maiores níveis de dependência grave em relação aos da escola particular (p < 0,001). Em relação à qualidade de vida, estudantes da escola particular apresentaram melhores indicadores no aspecto social (p < 0,01), enquanto aqueles da escola pública apresentaram melhores indicadores no aspecto escolar (p < 0,05). Os dados indicaram uma forte associação entre dependência de Internet e menores indicadores de qualidade de vida, conforme observado em estudos de outros países.

Acute consumption of organic and conventional tropical grape juices (Vitis labrusca L.) increases antioxidants in plasma and erythrocytes, but not glucose and uric acid levels, in healthy individuals.

Bioactive polyphenols in grapes are influenced by grape variety and cultivation conditions. The Vitis labrusca L. varieties are cultivated in tropical regions and used for grape juice production. We hypothesized that polyphenols from tropical grape juices would beneficially affect redox homeostasis in humans. Therefore, the effects of acute consumption of organic and conventional grape juices from V labrusca L. on antioxidants biomarkers were investigated in healthy individuals. In a controlled, randomized, crossover, intervention trial, 24 individuals were assigned to drink 400 mL of conventional juice, organic juice, or water. Each intervention was followed by a 14-day washout period. Blood samples were obtained before and 1 hour after acute intake and analyzed for erythrocyte reduced glutathione, serum total antioxidant capacity, antioxidant enzymes in erythrocytes, and glucose and uric acid in serum. The ingestion of both grape juices resulted in elevated levels of reduced glutathione (P< .001) and serum total antioxidant capacity (P< .05) and increased activity of catalase (P< .001), superoxide dismutase (P< .001), and glutathione peroxidase (P< .05) compared with the control intervention, with no significant differences between grape juices (P< .05). The intake of juices did not affect significantly the concentrations of glucose or uric acid. Grape juice polyphenols were associated with increased antioxidants, and the chemical differences between organic and conventional juices were not predictive of the observed responses. The results suggest a bioactive potential of V labrusca L. juices to improve redox homeostasis, which is involved in defense against oxidative stress in humans.

Bioactive potential of Vitis labrusca L. grape juices from the Southern Region of Brazil: phenolic and elemental composition and effect on lipid peroxidation in healthy subjects.

Grapes are rich in polyphenols with biologically active properties. Although the bioactive potential of grape constituents are frequently reported, the effects of Brazilian Vitis labrusca L. grape juices ingestion have not been demonstrated in humans. This study identified the phenolic and elemental composition of red and white grape juices and the effect of organic and conventional red grape juice consumption on lipid peroxidation in healthy individuals. Concentrations of anthocyanins, flavanols and phenolic acids and the in vitro antioxidant activity were significantly higher in the organic juice. The macro-elements K, Ca, Na and Mg were the most abundant minerals in all juices. The acute consumption of red grape juices promoted significant decrease of lipid peroxides in serum and TBARS levels in plasma. It is concluded that red V. labrusca L. grape juices produced in Southern Brazil showed lipid peroxidation inhibition abilities in healthy subjects, regardless of the cultivation system.