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 is inflammation of the pleura membrane covering the lungs. Pleurisy is also known as pleuritis and can cause chest pain with breathing. Around 2,000 people are admitted to hospital with pleurisy in England each year.Part of a doctor's diagnosis of pleurisy is listening to the chest to check for a distinctive dry and crunching sound with each breath.iral infection is probably the most common cause of pleurisy. Other causes include the following: 1  Lung infections, such as pneumonia and tuberculosis. 2  Diseases such as systemic lupus erythematosus (lupus), rheumatoid arthritis, cancer, liver diseases and pulmonary embolism.