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Enterotoxigenic Escherichia Coli
Enterotoxigenic ''Escherichia coli'' (ETEC) is a type of ''Escherichia coli'' and one of the leading bacterial causes of diarrhea in the developing world, as well as the most common cause of travelers' diarrhea. Insufficient data exists, but conservative estimates suggest that each year, about 157,000 deaths occur, mostly in children, from ETEC. A number of pathogenic isolates are termed ETEC, but the main hallmarks of this type of bacterium are expression of one or more enterotoxins and presence of fimbriae used for attachment to host intestinal cells. The bacterium was identified by the Bradley Sack lab in Kolkata in 1968. Signs and symptoms Infection with ETEC can cause profuse, watery diarrhea with no blood or leukocytes and abdominal cramping. Fever, nausea with or without vomiting, chills, loss of appetite, headache, muscle aches and bloating can also occur, but are less common. Pathogenic factors Attachment ETEC use fimbrial colonization factor (CF) or coli surface (C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infectious Disease (medical Speciality)
Infectious diseases (ID), also known as infectiology, is a medical specialty dealing with the diagnosis and treatment of infections. An infectious diseases specialist's practice consists of managing nosocomial ( healthcare-acquired) infections or community-acquired infections. An ID specialist investigates and determines the cause of a disease (bacteria, virus, parasite, fungus or prions). Once the cause is known, an ID specialist can then run various tests to determine the best drug to treat the disease. While infectious diseases have always been around, the infectious disease specialty did not exist until the late 1900s after scientists and physicians in the 19th century paved the way with research on the sources of infectious disease and the development of vaccines. Scope Infectious diseases specialists typically serve as consultants to other physicians in cases of complex infections, and often manage patients with HIV/AIDS and other forms of immunodeficiency. Although many co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escherichia Coli
''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly found in the lower intestine of warm-blooded organisms. Most ''E. coli'' strains are part of the normal microbiota of the gut, where they constitute about 0.1%, along with other facultative anaerobes. These bacteria are mostly harmless or even beneficial to humans. For example, some strains of ''E. coli'' benefit their hosts by producing vitamin K2 or by preventing the colonization of the intestine by harmful pathogenic bacteria. These mutually beneficial relationships between ''E. coli'' and humans are a type of mutualistic biological relationship—where both the humans and the ''E. coli'' are benefitting each other. ''E. coli'' is expelled into the environment within fecal matter. The bacterium grows massi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diarrhea
Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin with loss of the normal stretchiness of the skin and irritable behaviour. This can progress to decreased urination, loss of skin color, a fast heart rate, and a decrease in responsiveness as it becomes more severe. Loose but non-watery stools in babies who are exclusively breastfed, however, are normal. What is diarrhea? How is it caused, treated and prevented? (see also script)The most common cause is an infection of the intestines due to a virus, bacterium, or parasite—a condition also known as gastroenteritis. These infections are often acquired from food or water that has been contaminated by feces, or directly from another person who is infected. The three types of diarrhea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Travelers' Diarrhea
Travelers' diarrhea (TD) is a stomach and intestinal infection. TD is defined as the passage of unformed stool (one or more by some definitions, three or more by others) while traveling. It may be accompanied by abdominal cramps, nausea, fever, headache and bloating. Occasionally dysentery may occur. Most travelers recover within three to four days with little or no treatment. About 12% of people may have symptoms for a week. Bacteria are responsible for more than half of cases, typically via foodborne illness and waterborne diseases. The bacteria enterotoxigenic ''Escherichia coli'' (ETEC) are typically the most common except in Southeast Asia, where '' Campylobacter'' is more prominent. About 10 to 20 percent of cases are due to norovirus. Protozoa such as ''Giardia'' may cause longer term disease. The risk is greatest in the first two weeks of travel and among young adults. People affected are more often from the developed world. Recommendations for prevention include ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogen
In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a Germ theory of disease, germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or Transmission (medicine), transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterium
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in mutualistic, commensal and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterotoxin
An enterotoxin is a protein exotoxin released by a microorganism that targets the intestines. They can be chromosomally or plasmid encoded. They are heat labile (> 60 °C), of low molecular weight and water-soluble. Enterotoxins are frequently cytotoxic and kill cells by altering the apical membrane permeability of the mucosal (epithelial) cells of the intestinal wall. They are mostly pore-forming toxins (mostly chloride pores), secreted by bacteria, that assemble to form pores in cell membranes. This causes the cells to die. Clinical significance Enterotoxins have a particularly marked effect upon the gastrointestinal tract, causing traveler's diarrhea and food poisoning. The action of enterotoxins leads to increased chloride ion permeability of the apical membrane of intestinal mucosal cells. These membrane pores are activated either by increased cAMP or by increased calcium ion concentration intracellularly. The pore formation has a direct effect on the osmolarity of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fimbria (bacteriology)
A pilus (Latin for 'hair'; : pili) is a hair-like cell-surface appendage found on many bacteria and archaea. The terms ''pilus'' and '' fimbria'' (Latin for 'fringe'; plural: ''fimbriae'') can be used interchangeably, although some researchers reserve the term ''pilus'' for the appendage required for bacterial conjugation. All conjugative pili are primarily composed of pilin – fibrous proteins, which are oligomeric. Dozens of these structures can exist on the bacterial and archaeal surface. Some bacteria, viruses or bacteriophages attach to receptors on pili at the start of their reproductive cycle. Pili are antigenic. They are also fragile and constantly replaced, sometimes with pili of different composition, resulting in altered antigenicity. Specific host responses to old pili structures are not effective on the new structure. Recombination between genes of some (but not all) pili code for variable (V) and constant (C) regions of the pili (similar to immunoglobulin div ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bradley Sack
Richard Bradley Sack (October 25, 1935 – April 24, 2017) was an American physician and researcher noted for his contributions to the treatment of cholera. Early years Sack was born in Le Sueur, Minnesota to Wilma Mary (Hyink) and Rev. Nobel V. Sack. He grew up in Iowa and graduated from Lewis & Clark College. He then attended the University of Oregon School of Medicine, where he graduated in 1960. Career Sack did his residency at the University of Washington, followed by a fellowship with the Johns Hopkins Bloomberg School of Public Health. Sack joined the Johns Hopkins faculty in 1962. Sack's lab first identified Enterotoxigenic ''Escherichia coli'', a bacterium that is a major cause of diarrhea. He established two research centers funded by the NIH, one in Lima, Peru and one in the White Mountain Apache Reservation in Whiteriver, Arizona Whiteriver () is a census-designated place (CDP) located on the Fort Apache Indian Reservation in Navajo County, Arizona, United St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kolkata
Kolkata, also known as Calcutta ( its official name until 2001), is the capital and largest city of the Indian state of West Bengal. It lies on the eastern bank of the Hooghly River, west of the border with Bangladesh. It is the primary financial and commercial centre of eastern and northeastern India. Kolkata is the seventh most populous city in India with an estimated city proper population of 4.5 million (0.45 crore) while its metropolitan region Kolkata Metropolitan Area is the third most populous metropolitan region of India with a metro population of over 15 million (1.5 crore). Kolkata is regarded by many sources as the cultural capital of India and a historically and culturally significant city in the historic region of Bengal.————— The three villages that predated Calcutta were ruled by the Nawab of Bengal under Mughal suzerainty. After the Nawab granted the East India Company a trading license in 1690, the area was developed by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat-labile Enterotoxin
In molecular biology, the heat-labile enterotoxin family includes ''Escherichia coli'' heat-labile enterotoxin (Elt or LT) and cholera toxin (Ctx) secreted by ''Vibrio cholerae''. lt is so named because it is inactivated at high temperatures. Mechanism The A subunits are transported inside by the pentameric B subunits. It then acts by raising cAMP levels through ADP-ribosylation of the alpha-subunit of a Gs protein leading to the constitutive activation of adenylate cyclase. Elevated cAMP levels stimulate the activation of the CFTR channel thus stimulating secretion of chloride ions and water from the enterocyte into the gut lumen. This ionic imbalance causes watery diarrhea. In addition to its effects on chloride secretion, which involve the same steps as the effects of cholera toxin, Elt binds additional substrates: lipopolysaccharide on the surface of ''E. coli'' cells and A-type blood antigens. The importance of these binding events is not yet known. Structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat-stable Enterotoxin
Heat-stable enterotoxins (STs) are secretory peptides produced by some bacterial strains, such as enterotoxigenic Escherichia coli, enterotoxigenic ''Escherichia coli'' which are in general toxic to animals. These peptides keep their 3D structure and remain active at temperatures as high as 100 °C. Function Different STs recognize distinct receptors on the surface of animal cells and thereby affect different intracellular signaling pathways. For example, STa enterotoxins bind and activate membrane-bound guanylate cyclase, which leads to the intracellular accumulation of cyclic GMP and downstream effects on several signaling pathways. These events lead to the loss of electrolytes and water from intestinal cells. Heat-stable toxin 1 of entero-aggregative ''Escherichia coli'' (EAST1) is a small toxin. It is not, however, solely associated with entero-aggregative ''E. coli'' but also with many other diarrhoeic'' E. coli'' families. Some studies have established the role of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
