The genome of the organism that produces the world's most lethal toxin has been revealed. This toxin is the major weapon in the genome of Clostridium botulinum: less than two kg is enough to kill every person on the planet.
pneumothorax. entry of air into the pleural cavity in sufficient quantity to cause collapse of the lung and consequent respiratory embarrassment. If it is unilateral there is a mediastinal shift with displacement of the heart to the other side of the chest. Breath sounds are absent from the affected side. Pneumothorax.
Conditions Involving the Pleural Cavity. The presence of an excess of fluid, or of air or gas in the pleural cavity can interfere with its function in respiration. Some conditions affecting the pleural space may include: Pleural effusion - A pleural effusion refers to a build-up of fluid in the pleural cavity.