Combination of gemcitabine and cetuximab in patients with advanced cholangiocarcinoma: a phase II study

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Mecholyl aerosolized in the surrounding lung increases the resistance of the collateral pathways.

Collateral ventilation allows gas exchange in pulmonary units distal to an airway obstruction. Regional control of this airflow may be possible because smooth muscle exists in the wall of collateral pathways. Evidence of an intrasegmental cholinergic control of these pathways has been previously shown. We performed this study to investigate the possible control of collateral ventilation by cholinergic receptors situated in the surrounding lung. By using the wedged catheter technique, we measured collateral resistance before and after aerosolization of methacholine in the lung surrounding the wedged segment: both collateral resistance and the time constant for collateral ventilation increased, providing that a cholinergic stimulation in the surrounding lung can influence collateral pathways. Fast and complete reversibility was obtained after isoproterenol or atropine injection. Collateral obstruction would seem to be due, therefore, to a muscular spasm. The effective compliance of the wedged segment decreased during the spasm induced by mecholyl in the surrounding lung, and could be attributed to an increased interdependence of this segment with surrounding segments. This effect was immediately reversed by intravenous bronchodilators. We conclude that cholinergic receptors on the smooth muscles of the external collateral channels can control collateral ventilation

Effects of bronchomotor tone on regional distribution of ventilation and on collateral ventilation in dogs

Thèse d'agrégation de l'enseignement supérieur (Faculté de médecine) -- UCL, 198

Anatomy and physiology of collateral respiratory pathways.

When complete obstruction of an airway occurs, ventilation and gas exchange distal to the obstruction can be preserved if "collateral ventilation" exists. Three collateral pathways have been described: the interalveolar, the bronchioloalveolar and the interbronchiolar communications. The various techniques used to measure collateral flow, resistance, compliance and time constant are described, with particular attention to those trying to separate the resistances of intrasegmental and collateral pathways. The various techniques used to measure collateral flow, resistance, compliance and time constant are described, with particular attention to those trying to separate the resistances of intrasegmental and collateral pathways. The relative importance of collateral ventilation in humans and animals is shown; factors affecting this ventilation are described: type of flow, lung volume, surface tension, alveolar CO2, pulmonary circulation and oedema, cholinergic and adrenergic receptors, histamine, interdependence. Parenchymal diseases disturb collateral flow; on the other hand, collateral channels can provide alternative pathways in various human pathologies

Mechanisms in pulmonary toxicology.

Specific accumulation and biotransformation of drugs cause cell injury in the lung. Evoked mechanisms are oxidative injury, direct cytotoxic effects, intracellular deposition of phospholipids, and immune reaction. Individual susceptibility can be due to genetically determined metabolic idiosyncrasy or to immune-mediated hypersensitivity