Ventilatory parameters and maximal respiratory pressure changes with age in Duchenne muscular dystrophy patients.

The aim of this longitudinal study was to precise, in children with Duchenne muscular dystrophy, the respective functional interest of ventilatory parameters (Vital capacity, total lung capacity and forced expiratory volume in one second [FEV(1)]) in comparison to maximal inspiratory pressure (Pimax) during growth. In ten boys the mean age of 9.1 +/- 1 years) to mean age of 16 +/- 1.

[Respiratory function testing in infants: recommendations on normal values].

The present document is being produced on behalf of the French Society of the Physiology Task Force on standards for Infant Respiratory Function Testing whose aim is to provide guidelines for good laboratory practices according to the latest international recommendations. Application of such recommendations could be of particular value when attempting to develop standardized protocols in the scope of multi-centre trials. The first part resume these recommendations about apparatus, acquisition system and software for Infant Respiratory Function Testing.

L-arginine decreases inflammation and modulates the nuclear factor-kappaB/matrix metalloproteinase cascade in mdx muscle fibers.

Duchenne muscular dystrophy (DMD) is a lethal, X-linked disorder associated with dystrophin deficiency that results in chronic inflammation, sarcolemma damage, and severe skeletal muscle degeneration. Recently, the use of L-arginine, the substrate of nitric oxide synthase (nNOS), has been proposed as a pharmacological treatment to attenuate the dystrophic pattern of DMD. However, little is known about signaling events that occur in dystrophic muscle with l-arginine treatment.

Role of respiratory system impedance in the difference of ventilatory control between children and adults.

How children are able to adapt their ventilation to the intensity of exercise faster than adults remain unclear. We hypothesized that differences of VE observed between children and adults depend on either peripheral chemoreceptors or central command activity. We examined ventilatory control parameters in either normoxic or hypoxic condition (FI 02 =0.

Alteration of the piglet diaphragm contractility in vivo and its recovery after acute hypercapnia.

Background: The effects of hypercapnic acidosis on the diaphragm and its recovery to normocapnia have been poorly evaluated. The authors studied diaphragmatic contractility facing acute variations of arterial carbon dioxide tension (Paco2) and evaluated the contractile function at 60 min after normocapnia recovery.

Methods: Thirteen piglets weighing 15-20 kg were anesthetized, ventilated, and separated into two groups: a control group (n = 5) evaluated in normocapnia (time-control experiments) and a hypercapnia group (n = 8) in which animals were acutely and shortly exposed to five consecutive ranges of Paco2 (40, 50, 70, 90, and 110 mmHg).