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%.
While it is not uncommon for the precise source of chest wall pain to remain unknown, some possible causes of costochondritis include: Injury or trauma: Pain within the area of the chest wall may emerge as the result of a direct blow or injury to the area.