Helicobacter Pylori

Helicobacter Pylori

Helicobacter pylori is a spiral gram-negative bacterium that infects various areas of the stomach and duodenum. Many cases of gastric ulcers and duodenal ulcers, gastritis, duodenitis, and possibly some cases of lymphoma of the stomach and gastric cancer etiologically related to infection by Helicobacter pylori. However, the majority (90%) infected with Helicobacter pylori carriers show no symptoms of disease. The name of the bacteria Helicobacter pylori is derived from "pylori", pointing to the main dwelling place - the pyloric part of stomach, and "Helika" which characterizes the form of bacteria: helical, spiral. The authors of this discovery, Dr. Barry Marshall and Robin Warren received the prestigious Nobel Prize in Medicine in 2005.

Historical Background

In 1875, German scientists discovered a spiral bacteria in the stomachs of the humans. In 1893 an Italian researcher Giulio Bizzotsero described a similar spiral bacteria in an acidic stomach contents of dogs. This bacterium was rediscovered in 1979 by the pathologist Australian Robin Warren, who in later research (from 1981), along with Barry Marshall discovered that the organism was isolated from the mucosa of human stomachs. They were the first who managed to cultivate it. Helicobacter pylori has the ability to form biofilms, bacteria contribute to immunity to antibiotics and protect bacterial cells from the host immune response (Brown, pp. 97). It is believed that this increases its survival in acidic and corrosive environment of the stomach. In 1899 the Polish professor Valery Jaworski of the Jagiellonian University in Krakow , studying sediment from washing water of the stomach of man , found, in addition to bacteria , resembling a twig, as a number of bacteria, a characteristic spiral shape. He called the discovered the bacterium Vibrio rugula. His work on this subject was included in the Polish "Guide to Diseases of the stomach." However, this work did not have much impact on the rest of the medical and scientific world, as was written in Polish .

Structure

Helicobacter pylori is a spiral gram-negative bacteria and is about 3 mm in length with a diameter of about 0.5 microns. It has 4.6 flagella and has the ability to move extremely quickly, even in the thick mucus or agar. It is microaerophilic, ie, requires for its development of the presence of oxygen, but in much lower concentrations than those contained in the atmosphere. The bacterium contains a hydrogenase, which can produce other intestinal bacteria. The bacterium also produces oxidase, catalase, and urease. Helicobacter pylori has the ability to form biofilms, bacteria contribute to immunity to antibiotics and protect bacterial cells from the host immune response. It is believed that this increases its survival in acidic and corrosive environment of the stomach (Boyanova, pp. 45).

Thanks to its helical shape and its flagella, the bacterium slips through the mucus and sometimes the lining of the stomach by anchoring cells to epithelial through adhesins (binding proteins). It then secretes an enzyme called "urease "which converts urea into ammonia and carbon dioxide. This ammonia will partially neutralize stomach acid (which is used to ...