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.
1 Pleurisy is caused by a variety of conditions, such as infections, tuberculosis (TB), congestive heart failure, cancer, pulmonary embolism, and collagen vascular diseases. 2  Symptoms of pleurisy include pain in the chest, which is aggravated by breathing in, shortness of breath, and local tenderness.