Delayed Toxicity Associated with Soluble Anthrax Toxin Receptor Decoy-Ig Fusion Protein Treatment

Soluble receptor decoy inhibitors, including receptor-immunogloubulin (Ig) fusion proteins, have shown promise as candidate anthrax toxin therapeutics. These agents act by binding to the receptor-interaction site on the protective antigen (PA) toxin subunit, thereby blocking toxin binding to cell surface receptors. Here we have made the surprising observation that co-administration of receptor decoy-Ig fusion proteins significantly delayed, but did not protect, rats challenged with anthrax lethal toxin. The delayed toxicity was associated with the in vivo assembly of a long-lived complex comprised of anthrax lethal toxin and the receptor decoy-Ig inhibitor. Intoxication in this system presumably results from the slow dissociation of the toxin complex from the inhibitor following their prolonged circulation. We conclude that while receptor decoy-Ig proteins represent promising candidates for the early treatment of B. anthracis infection, they may not be suitable for therapeutic use at later stages when fatal levels of toxin have already accumulated in the bloodstream

Associações entre atividade física, índice de massa corporal e comportamentos sedentários em adolescentes Associations between physical activity, body mass index, and sedentary behaviors in adolescents

OBJETIVO: Este estudo teve como objetivo determinar a associação do índice de massa corporal (IMC) com os níveis de atividade física (AF) e comportamentos sedentários (assistir TV, usar computador ou jogar videogames) em adolescentes de escolas públicas do Estado de Santa Catarina (15-19 anos; n = 5.028). MÉTODOS: As informações foram coletadas por meio de questionário desenvolvido e validado para adolescentes. Foram considerados insuficientemente ativos, os jovens que não acumulavam pelo menos 300 minutos/semana de atividades físicas moderadas ou vigorosas. Considerou-se para o uso excessivo de TV e computador/games um tempo > 2 horas/dia; para excesso de peso corporal, utilizou-se a tabela internacional de IMC para adolescentes. RESULTADOS: O excesso de peso corporal foi mais prevalente entre os rapazes (12,7% vs 7,9%, p<0,001), e houve uma maior proporção de moças insuficientemente ativas (37,0% vs 21,0%, p<0,001). A chance de ter excesso de peso corporal foi 74% maior entre os rapazes pouco ativos em comparação com os ativos, e entre as moças de menor renda familiar (OR=1,85) e as que residiam na zona urbana (OR=2,22). A chance de serem menos ativos foi 43% maior entre os rapazes que assistiam mais TV e 73% maior para aqueles com excesso de peso corporal. Nas moças, a chance de pouca atividade física foi 54% maior entre as que trabalhavam. CONCLUSÕES: a prevalência de excesso de peso corporal foi maior entre os rapazes, mesmo sendo mais ativos do que as moças. Nos rapazes, o excesso de peso estava significativamente associado à menor prática de atividade física e, nas moças, à menor renda familiar e local de moradia.<br>OBJECTIVE: The objective of this study was to analyze the associations of body mass index (BMI) with physical activity, sedentary behaviors (TV, computer/videogames) in a representative sample (n=5,028) of adolescents (15-19 years) in the State of Santa Catarina, Brazil. METHODS: Data was collected using a validated health behavior questionnaire developed for adolescents. Excess body weight was determined according to the international BMI tables developed for adolescents. Students were classified as not being physically active if they reported having less than 300 minutes of moderate/vigorous physical activity (MVPA) per week. Two or more hours a day was considered excess screen time (TV, computer, games). RESULTS: Excess body weight was more prevalent (p<0.001) among boys (12.7%) than girls (7.9%), but inadequate physical activity was more prevalent (p<0.001) among girls (37%) than boys (21%). Less active boys had a greater chance (74%) of having excess body weight when compared to active ones. Among girls, those belonging to families with lower income (OR=1.85) and living in urban areas (OR=2.22) were at greater risk of having excess body weight. An inadequate level of physical activity was seen among boys with excess screen time or excess body weight. Also, working girls were more likely (54%) of being less active. CONCLUSIONS: Excess body weight was more prevalent among boys, although they were more active than girls. For boys, excess body weight was inversely associated with physical activity, while, for girls, it was more prevalent among those with lower income and who lived in urban areas