Exercise-induced reversal of age-related declines of oxidative reactions, mitochondrial yield, and flavins in skeletal muscle of the rat

The ability of gastrocnemius muscle homogenates to catalyze the oxidation of succinate, glutamate + malate, pyruvate + malate, palmitoyl-coenzyme A, decanoylcarnitine and palmitoylcarnitine in the presence of ADP decreased by approximately 32% in sedentary male Sprague-Dawley rats between the ages of 9 and 25 months. Following 21 weeks of treadmill training (running), such homogenates from 25-month-old animals catalyzed oxidations 55% more rapidly than those from 25-month-old sedentary rats, and 17% faster than those from 9-month-old sedentary rats. Total and peptide-bound flavin of gastrocnemius muscles also declined between 9 and 25 months of age and were elevated in the 25-month-old endurance trained rats to levels greater than both 9- and 25-month-old sedentary animals. The yield of protein in the mitochondrial fraction from the quadriceps femoris muscle decreased between 9 and 25 months and was restored to the 9-month level by endurance training. The kinetic characteristics of the isolated mitochondria were not influenced by age or exercise. These data indicate that 2-year-old rats retain the capacity to increase skeletal muscle oxidative capacity and mitochondrial population density in response to endurance training.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24891/1/0000318.pd

Análise da eficácia do metilfenidato usando a versão abreviada do questionário de conners em transtorno de déficit de atenção/hiperatividade Analysis of the methylphenidate's efficacy using the abbreviated version Conners' questionnaire in attention deficit hyperactivity disorder

O transtorno de déficit de atenção/hiperatividade (TDAH) é quadro diagnóstico bastante complexo, de início precoce, com evolução crônica que repercute em diversos contextos. Três a 5% das crianças em idade escolar apresentam esse transtorno. O questionário de Conners vem sendo utilizado como instrumento de levantamento epidemiológico para o TDAH. OBJETIVO: Este estudo visa a utilização deste instrumento para a análise da eficácia do tratamento com metilfenidato em crianças com TDAH. MÉTODO: Foram selecionadas 21 crianças do gênero masculino, com TDAH do tipo combinado, idade cronológica entre sete anos completos a 10 anos e 11 meses e todos foram tratados com metilfenidato. A versão abreviada do questionário de Conners para pais e professores foi aplicada em dois momentos: um antes da medicação e outro entre seis a oito meses após o seu início. RESULTADOS: Obteve-se redução na pontuação no questionário de Conners em todas as crianças com TDAH concomitante à melhora clínica. CONCLUSÃO: Observou-se que o questionário de Conners mostrou-se útil não só como auxílio diagnóstico, mas também como um instrumento de avaliação da eficácia do tratamento do TDAH.<br>The attention deficit/hyperactivity disorder (ADHD) is a complex diagnosis. Its installation is precocious, with chronic evolution that impacts on the subject's performance in several contexts. Three to 5% of the school aged children present this disorder. The Conners' questionnaire has been used as an instrument of epidemiological survey for ADHD children. OBJECTIVE: This study aimed to investigate if this instrument could be an useful tool for the analysis of the methylphenidate's treatment efficacy in ADHD's children. METHOD: Twenty-one male children were selected, with ADHD combined type, chronological ages ranging from seven to 10 years and 11 months and all were treated with methylphenidate. The Conners' questionnaire abbreviated version for parents and teachers was applied in two moments, one without medication and another between six to eight months after the beginning of the methylphenidate. RESULTS: Results pointed to a reduction in punctuation in Conners' questionnaire in all children with ADHD concomitant to clinical improvement. CONCLUSION: Conners' questionnaire revealed to be useful not only for diagnosis, but also as an instrument to evaluate the effectiveness of the treatment of ADHD