RESUMEN
OBJECTIVE: To determine whether pentoxifylline (PTX) slows the decline of muscle strength and function in ambulatory boys with Duchenne muscular dystrophy (DMD). METHODS: This was a multicenter, randomized, double-blinded, controlled trial comparing 12 months of daily treatment with PTX or placebo in corticosteroid-treated boys with DMD using a slow-release PTX formulation (~20 mg/kg/day). The primary outcome was the change in mean total quantitative muscle testing (QMT) score. Secondary outcomes included changes in QMT subscales, manual muscle strength, pulmonary function, and timed function tests. Outcomes were compared using Student t tests and a linear mixed-effects model. Adverse events (AEs) were compared using the Fisher exact test. RESULTS: A total of 64 boys with DMD with a mean age of 9.9 ± 2.9 years were randomly assigned to PTX or placebo in 11 participating Cooperative International Neuromuscular Research Group centers. There was no significant difference between PTX and the placebo group in total QMT scores (p = 0.14) or in most of the secondary outcomes after a 12-month treatment. The use of PTX was associated with mild to moderate gastrointestinal or hematologic AEs. CONCLUSION: The addition of PTX to corticosteroid-treated boys with DMD at a moderate to late ambulatory stage of disease did not improve or halt the deterioration of muscle strength and function over a 12-month study period. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that treatment with PTX does not prevent deterioration in muscle function or strength in corticosteroid-treated boys with DMD.
Asunto(s)
Distrofia Muscular de Duchenne/tratamiento farmacológico , Pentoxifilina/uso terapéutico , Inhibidores de Fosfodiesterasa/uso terapéutico , Corticoesteroides/uso terapéutico , Niño , Preparaciones de Acción Retardada , Progresión de la Enfermedad , Método Doble Ciego , Quimioterapia Combinada , Humanos , Masculino , Fuerza Muscular/fisiología , Distrofia Muscular de Duchenne/fisiopatología , Distrofia Muscular de Duchenne/psicología , Examen Neurológico , Pentoxifilina/administración & dosificación , Pentoxifilina/efectos adversos , Inhibidores de Fosfodiesterasa/administración & dosificación , Inhibidores de Fosfodiesterasa/efectos adversos , Calidad de Vida , Pruebas de Función Respiratoria , Tamaño de la Muestra , Resultado del TratamientoRESUMEN
The acquisition of immunity by chickens infected 18 h post-hatch with 100 oocysts of Eimeria maxima and reared in floor-pens in contact with their droppings was investigated. In the first experiment, birds were placed on new litter and immunity was measured at 2, 3, 4, and 5 weeks by calculation of weight gain from days 0 to 7 following challenge with 100000 oocysts or by oocyst production in the faeces from days 5 to 8 following challenge with 500 oocysts. In the second experiment, birds were placed on new litter or reused litter from the first experiment (1 week after birds from the first experiment had been removed when 6 weeks of age), and were challenged at 1, 2, and 3 weeks of age. In the first experiment, immunity had developed in birds challenged at 3, 4, and 5 weeks, judged by weight gain and oocyst production, but immunity was not complete at 2 weeks. In the second experiment, immunity had developed in birds challenged at 1, 2, and 3 weeks measured by either criterion. In both experiments, birds produced small numbers of oocysts in their faeces following challenge. Judged by the weight gain following challenge, no significant difference in the acquisition of immunity was observed whether birds were reared on new or reused litter.