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Intestinal Metaplasia
Intestinal metaplasia is the transformation (metaplasia) of epithelium (usually of the stomach or the esophagus) into a type of epithelium resembling that found in the intestine. In the esophagus, this is called Barrett's esophagus. Chronic inflammation caused by '' H. pylori'' infection in the stomach and GERD in the esophagus are seen as the primary instigators of metaplasia and subsequent adenocarcinoma formation. Initially, the transformed epithelium resembles the small intestine lining; in the later stages it resembles the lining of the colon. It is characterized by the appearance of goblet cells and expression of intestinal cell markers such as the transcription factor, CDX2. Risk factors Although it was originally reported that people of East Asian ethnicity with gastric intestinal metaplasia are at increased risk of stomach cancer Stomach cancer, also known as gastric cancer, is a cancer that develops from the Gastric mucosa, lining of the stomach. Most cases of stoma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barrett's Esophagus
Barrett's esophagus is a condition in which there is an abnormal ( metaplastic) change in the mucosal cells lining the lower portion of the esophagus, from stratified squamous epithelium to simple columnar epithelium with interspersed goblet cells that are normally present only in the small intestine and large intestine. This change is considered to be a premalignant condition because it is associated with a high incidence of further transition to esophageal adenocarcinoma, an often-deadly cancer. The main cause of Barrett's esophagus is thought to be an adaptation to chronic acid exposure from reflux esophagitis. Barrett's esophagus is diagnosed by endoscopy: observing the characteristic appearance of this condition by direct inspection of the lower esophagus; followed by microscopic examination of tissue from the affected area obtained from biopsy. The cells of Barrett's esophagus are classified into four categories: nondysplastic, low-grade dysplasia, high-grade dysplasia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicobacter Pylori
''Helicobacter pylori'', previously known as ''Campylobacter pylori'', is a gram-negative, microaerophilic, spiral (helical) bacterium usually found in the stomach. Its helical shape (from which the genus name, helicobacter, derives) is thought to have evolved in order to penetrate the mucoid lining of the stomach and thereby establish infection. The bacterium was first identified in 1982 by the Australian doctors Barry Marshall and Robin Warren. ''H. pylori'' has been associated with cancer of the mucosa-associated lymphoid tissue in the stomach, esophagus, colon, rectum, or tissues around the eye (termed extranodal marginal zone B-cell lymphoma of the cited organ), and of lymphoid tissue in the stomach (termed diffuse large B-cell lymphoma). ''H. pylori'' infection usually has no symptoms but sometimes causes gastritis (stomach inflammation) or ulcers of the stomach or first part of the small intestine. The infection is also associated with the developm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stomach Cancer
Stomach cancer, also known as gastric cancer, is a cancer that develops from the Gastric mucosa, lining of the stomach. Most cases of stomach cancers are gastric carcinomas, which can be divided into a number of subtypes, including gastric adenocarcinomas. Lymphomas and mesenchymal tumors may also develop in the stomach. Early symptoms may include heartburn, upper abdominal pain, nausea, and Anorexia (symptom), loss of appetite. Later signs and symptoms may include weight loss, jaundice, yellowing of the skin and whites of the eyes, Hematemesis, vomiting, Dysphagia, difficulty swallowing, and Melena, blood in the stool, among others. The cancer may metastasis, spread from the stomach to other parts of the body, particularly the liver, lungs, bones, peritoneum, lining of the abdomen, and lymph nodes. The most common cause is infection by the bacterium ''Helicobacter pylori'', which accounts for more than 60% of cases. Certain types of ''H. pylori'' have greater risks than others. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Factor
In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription of genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The function of TFs is to regulate—turn on and off—genes in order to make sure that they are expressed in the desired cells at the right time and in the right amount throughout the life of the cell and the organism. Groups of TFs function in a coordinated fashion to direct cell division, cell growth, and cell death throughout life; cell migration and organization ( body plan) during embryonic development; and intermittently in response to signals from outside the cell, such as a hormone. There are up to 1600 TFs in the human genome. Transcription factors are members of the proteome as well as regulome. TFs work alone or with other proteins in a complex, by promoting (as an activator), or blocking (as a repressor) the recruitment o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colon (anatomy)
The large intestine, also known as the large bowel, is the last part of the gastrointestinal tract and of the digestive system in tetrapods. Water is absorbed here and the remaining waste material is stored in the rectum as feces before being removed by defecation. The colon is the longest portion of the large intestine, and the terms are often used interchangeably but most sources define the large intestine as the combination of the cecum, colon, rectum, and anal canal. Some other sources exclude the anal canal. In humans, the large intestine begins in the right iliac region of the pelvis, just at or below the waist, where it is joined to the end of the small intestine at the cecum, via the ileocecal valve. It then continues as the colon ascending the abdomen, across the width of the abdominal cavity as the transverse colon, and then descending to the rectum and its endpoint at the anal canal. Overall, in humans, the large intestine is about long, which is about one-fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
