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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 lining of the stomach. Most cases of stomach cancers are gas ... [...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, and fr ... [...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 development of cer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stomach Cancer
Stomach cancer, also known as gastric cancer, is a cancer that develops from the 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 loss of appetite. Later signs and symptoms may include weight loss, yellowing of the skin and whites of the eyes, vomiting, difficulty swallowing, and blood in the stool, among others. The cancer may spread from the stomach to other parts of the body, particularly the liver, lungs, bones, 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. Smoking, dietary factors such as pickled vegetables and obesity are other risk factors. About 10% ... [...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 of RNA ... [...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-fifth o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Intestine
The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion. The small intestine is about long and folds many times to fit in the abdomen. Although it is longer than the large intestine, it is called the small intestine because it is narrower in diameter. The small intestine has three distinct regions – the duodenum, jejunum, and ileum. The duodenum, the shortest, is where preparation for absorption through small finger-like protrusions called villi begins. The jejunum is specialized for the absorption through its lining by enterocytes: small nutrient particles which have been previously digested by enzymes in the duodenum. The main function of the ileum is to absorb vitamin B12, bile salts, and whatever products of digestion that were not absorbed by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenocarcinoma
Adenocarcinoma (; plural adenocarcinomas or adenocarcinomata ) (AC) is a type of cancerous tumor that can occur in several parts of the body. It is defined as neoplasia of epithelial tissue that has glandular origin, glandular characteristics, or both. Adenocarcinomas are part of the larger grouping of carcinomas, but are also sometimes called by more precise terms omitting the word, where these exist. Thus invasive ductal carcinoma, the most common form of breast cancer, is adenocarcinoma but does not use the term in its name—however, esophageal adenocarcinoma does to distinguish it from the other common type of esophageal cancer, esophageal squamous cell carcinoma. Several of the most common forms of cancer are adenocarcinomas, and the various sorts of adenocarcinoma vary greatly in all their aspects, so that few useful generalizations can be made about them. In the most specific usage (narrowest sense), the glandular origin or traits are exocrine; endocrine gland tumors, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastroesophageal Reflux Disease
Gastroesophageal reflux disease (GERD) or gastro-oesophageal reflux disease (GORD) is one of the upper gastrointestinal chronic diseases where stomach content persistently and regularly flows up into the esophagus, resulting in symptoms and/or complications. Symptoms include dental corrosion, dysphagia, heartburn, odynophagia, regurgitation, non-cardiac chest pain, extraesophageal symptoms such as chronic cough, hoarseness, reflux-induced laryngitis, or asthma. On the long term, and when not treated, complications such as esophagitis, esophageal stricture, and Barrett's esophagus may arise. Risk factors include obesity, pregnancy, smoking, hiatal hernia, and taking certain medications. Medications that may cause or worsen the disease include benzodiazepines, calcium channel blockers, tricyclic antidepressants, NSAIDs, and certain asthma medicines. Acid reflux is due to poor closure of the lower esophageal sphincter, which is at the junction between the stomach and the esoph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intestine
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and other animals, including the esophagus, stomach, and intestines. Food taken in through the mouth is digested to extract nutrients and absorb energy, and the waste expelled at the anus as feces. ''Gastrointestinal'' is an adjective meaning of or pertaining to the stomach and intestines. Most animals have a "through-gut" or complete digestive tract. Exceptions are more primitive ones: sponges have small pores ( ostia) throughout their body for digestion and a larger dorsal pore (osculum) for excretion, comb jellies have both a ventral mouth and dorsal anal pores, while cnidarians and acoels have a single pore for both digestion and excretion. The human gastrointestinal tract consists of the esophagus, stomach, and intestines, and is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goblet Cell
Goblet cells are simple columnar epithelial cells that secrete gel-forming mucins, like mucin 5AC. The goblet cells mainly use the merocrine method of secretion, secreting vesicles into a duct, but may use apocrine methods, budding off their secretions, when under stress. The term ''goblet'' refers to the cell's goblet-like shape. The apical portion is shaped like a cup, as it is distended by abundant mucus laden granules; its basal portion lacks these granules and is shaped like a stem. The goblet cell is highly polarized with the nucleus and other organelles concentrated at the base of the cell and secretory granules containing mucin, at the apical surface. The apical plasma membrane projects short microvilli to give an increased surface area for secretion. Goblet cells are typically found in the respiratory, reproductive and gastrointestinal tracts and are surrounded by other columnar cells. Biased differentiation of airway basal cells in the respiratory epithelium, into gobl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophagus
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about long in adults, that travels behind the trachea and heart, passes through the diaphragm, and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word ''oesophagus'' is from Ancient Greek οἰσοφάγος (oisophágos), from οἴσω (oísō), future form of φέρω (phérō, “I carry”) + ἔφαγον (éphagon, “I ate”). The wall of the esophagus from the lumen outwards consists of mucosa, submucosa (connective tissue), layers of muscle fibers between layers of fibrous tissue, and an outer layer of connective tissue. The mucosa is a stratified squamous epithel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_and_foveolar_cells_in_incomplete_Barrett's_esophagus.jpg "Click for more on -> Goblet Cell")
