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.
Pleurisy, also called pleuritis, is an inflammation of the pleura, which is the moist, double-layered membrane that surrounds the lungs and lines the rib cage. The condition can make breathing extremely painful.ome of the other causes include: 1  Lung infections, such as pneumonia and tuberculosis. 2  Other diseases such as systemic lupus erythematosus (lupus), rheumatoid arthritis, cancer, liver diseases, and pulmonary embolism. 3  Chest injuries. 4  Drug reactions.