1.4 Chemical Determination. Proteins are complex, organic compounds composed of many amino acids linked together through peptide bonds and cross-linked between chains by sulfhydryl bonds, hydrogen bonds and van der Waals forces.
What causes pleurisy? In young, healthy people, an infection of the lower respiratory system by a virus or bacteria may cause pleurisy. Pleurisy usually lasts a few days to 2 weeks. In very rare cases, the virus or bacteria may spread and cause pleurisy in others. Other causes of pleurisy include air leaking into the pleural cavity from a hole in a lung (pneumothorax), injury to the chest (such as a broken rib), tuberculosis or other infections, or a tumor in the pleura.
Most of the time, it happens because of an infection. If your doctor treats your infection, that can make the pleurisy -- and the pain -- go away. Causes. Bacterial infections such as pneumonia often cause pleurisy. It can also be caused by a virus such as the flu, or by a fungus. Some other things that can cause pleurisy to strike are: Lung cancer