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Who first described redness, heat, swelling, and pain as signs of inflammation?
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inflammation
The main function of complement proteins is to aid in the destruction of pathogens by piercing their outer membranes (cell lysis) or by making them more attractive to phagocytic cells such as macrophages (a process known as opsonization). Some complement components also promote inflammation by stimulating cells to release histamine and by attracting phagocytic cells to the site of infection.
The four cardinal signs of inflammationâredness (rubor), heat (calor), swelling (tumor), and pain (dolor)âwere first described in the 1st century CE by the Roman medical writer Aulus Cornelius Celsus.1
These signs occur due to specific physiological changes:
* Redness: Caused by the dilation of small blood vessels in the injured area.1
* Heat: Results from increased blood flow to the site.1
* Swelling: Known as edema, this is primarily caused by the accumulation of fluid outside the blood vessels.1
* Pain: Induced by tissue distortion from edema and the release of chemical mediators such as serotonin and prostaglandins.1
A fifth sign, loss of function, was later identified by the 19th-century German pathologist Rudolf Virchow.1