A key process in surfactant secretion is exocytosis of LB, and there have been several ultrastructural observations of lamellar material passing from AT II cells into alveoli (reviewed in ref.
In one general practice sample, costochondritis, also known as costosternal syndrome and anterior chest wall syndrome, was the most common specific cause of anterior musculoskeletal chest pain, with a prevalence of 13%.
Costochondritis is a painful condition of the chest wall. It is caused by inflammation in the joints between the cartilages that join the ribs to the breastbone (sternum). Although painful, it is not a serious condition. Usually it has no obvious cause and settles over time.