Infectious diseases and drugs

19. People throughout the word become victims of tuberculosis and meningococcal meningitis boils and carbuncles may cover the bodies of many of them too. Define the group these diseases can be referred to according to their causative agent. Describe it.

These diseases are caused by bacteria. Bacteria are microscopic, one-celled organisms. They rank among the most widespread of all living things.

Most bacterial diseases result when bacteria multiply rapidly in the living tissue, damaging or killing it. Boils and carbuncles result from the multiplication of bacteria in the skin. Bacterial pneumonia occurs when bacteria invade the lungs and multiply there. Many others serious diseases, including tuberculosis, result from bacterial multiplication.

20. 1928 Is notable due to Fleming’s accidental discovery. Name the antibacterial substance that became a breakthrough in medicine. Outline the history of its discovery and the ways it works.

Penicillin is a powerful drug used to treat infectious caused by bacteria. It was the first antibiotic (drug produced by microbes) used successfully in the treatment of serious diseases.

Penicillin kills bacteria by preventing the formation of the stiff cell walls bacteria need to survive. The cells of animals don’t form stiff cell walls and so are not damaged by penicillin.

Fleming discovered penicillin in 1928 when he noticed mold growing in a laboratory dish that contained common bacteria. Examining the dish, he saw that bacteria around the mold had been killed. Then he grew the mold in a liquid and observed that the liquid kept bacteria from growing in test tubes. However Fleming had trouble extracting the bacteria-killing substance from the liquid.

During the late 1930s, a group of British researchers developed a method of extracting and purifying small amounts of penicillin. During the next several years, researchers found methods of producing large quantities of penicillin. One of these forms, penicillin G, proved the most effective in fighting bacteria. It is used in treatment many diseases, including pneumonia and rheumatic fever. But it didn’t kill certain kinds of bacteria. Some bacteria became resistant to penicillin G after few years.

To overcome the problems with penicillin G, chemists began to make semisynthetic penicillins in the late 1950s. Today many semisynthetic penicillins are available. Most of them have one or more properties that penicillin G lacks. For example, ampicillin and amoxicillin are effective against some kinds of bacteria resistant to penicillin G.

21. The patient has been admitted to the hospital with some form of meningitis. Define the group of antibacterial drugs that should be administered in this case. Provide the information of its discovery, indications and side effects it may trigger.

Cephalosporin is any of a group of widely used antibiotics. Doctors used cephalosporins to treat a variety of bacterial infections, including diseases of the respiratory system, urinary tract, bloodstream, skin. Some cephalosporins are used to treat some form of meningitis.

Cephalosporin is chemically similar to penicillin and they have many similar properties. Still, cephalosporin fights more kinds of bacteria.

Like penicillin, cephalosporin fight bacteria by preventing the bacteria from making the rigid cell walls that they need to live.

The first cephalosporin was found in 1948. Since then, many cephalosporins have become available. One of the most commonly prescribed kinds is cephalexin.

Cephalosporin can cause diarrhea, hypertension, allergy. It can also disturb the balance of the normal body flora.