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.
Tension pneumothorax: The most serious type of pneumothorax, this occurs when the pressure in the pleural space is greater than the atmospheric pressure, either because air becomes trapped in the pleural space or because the entering air is from a positive-pressure mechanical ventilator.
Occasionally, a lung will collapse without any direct injury to the lung or chest. This is called a spontaneous pneumothorax. This is more likely to happen in people with lung disease. It is particularly common in emphysema, which causes air-filled sacs, called blebs, to form.