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Diarrheal Shellfish Poisoning
Diarrheic shellfish poisoning (DSP) is one of the four recognized symptom types of shellfish poisoning, alongside paralytic shellfish poisoning, neurotoxic shellfish poisoning and amnesic shellfish poisoning. As the name suggests, it mainly manifests as diarrhea. Abdominal pain, nausea and vomiting may also occur. DSP and its symptoms usually set in within about half an hour of ingesting infected shellfish, and last for about one day. The causative poison is okadaic acid, which inhibits intestinal cellular dephosphorylation. This causes the cells to become very water-permeable and the host to profusely defecate into a high risk of dehydration. See also * Amnesic shellfish poisoning (ASP) * Harmful algal blooms (HABs) * Neurotoxic shellfish poisoning (NSP) * Paralytic shellfish poisoning Paralytic shellfish poisoning (PSP) is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks (such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shellfish Poisoning
Shellfish poisoning includes four syndromes that share some common features and are primarily associated with bivalve molluscs (such as mussels, clams, oysters and scallops.) As filter feeders, these shellfish may accumulate toxins produced by microscopic organisms, such as cyanobacteria, diatoms and dinoflagellates. Syndromes The syndromes are: * Amnesic shellfish poisoning (ASP) * Diarrheal shellfish poisoning (DSP) * Neurotoxic shellfish poisoning (NSP) * Paralytic shellfish poisoning (PSP) See also * Cyanotoxin * Gonyaulax ''Gonyaulax'' is a genus of dinoflagellates with the type species ''Gonyaulax spinifera'' (Claparède et Lachmann) Diesing. ''Gonyaulax'' belongs to red dinoflagellates and commonly causes red tides. It can produce yesotoxins: for example, strai ... References External links Human Illness Associated with Harmful Algae {{Authority control Seafood Toxic effect of noxious substances eaten as food ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dephosphorylation
In biochemistry, dephosphorylation is the removal of a phosphate () group from an organic compound by hydrolysis. It is a reversible post-translational modification. Dephosphorylation and its counterpart, phosphorylation, activate and deactivate enzymes by detaching or attaching phosphoric esters and anhydrides. A notable occurrence of dephosphorylation is the conversion of Adenosine triphosphate, ATP to Adenosine diphosphate, ADP and inorganic phosphate. Dephosphorylation employs a type of hydrolytic enzyme, or hydrolase, which cleaves ester bonds. The prominent hydrolase subclass used in dephosphorylation is phosphatase, which removes phosphate groups by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl (–OH) group. The reversible phosphorylation-dephosphorylation reaction occurs in every physiological process, making proper function of protein phosphatases necessary for organism viability. Because protein dephosphorylation is a k ... [...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] |
Paralytic Shellfish Poisoning
Paralytic shellfish poisoning (PSP) is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks (such as mussels, clams, oysters and scallops). These shellfish are filter feeders and accumulate neurotoxins, chiefly saxitoxin, produced by microscopic algae, such as dinoflagellates, diatoms, and cyanobacteria. Dinoflagellates of the genus '' Alexandrium'' are the most numerous and widespread saxitoxin producers and are responsible for PSP blooms in subarctic, temperate, and tropical locations. The majority of toxic blooms have been caused by the morphospecies '' Alexandrium catenella, Alexandrium tamarense'', '' Gonyaulax catenella'' and '' Alexandrium fundyense'', which together comprise the ''A. tamarense'' species complex. In Asia, PSP is mostly associated with the occurrence of the species ''Pyrodinium bahamense''. Some pufferfish, including the chamaeleon puffer, also contain saxitoxin, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotoxic Shellfish Poisoning
Neurotoxic shellfish poisoning (NSP) is caused by the consumption of brevetoxins, which are marine toxins produced by the dinoflagellate ''Karenia brevis'' (among several others). These toxins can produce a series of gastrointestinal and neurological effects. Outbreaks of NSP commonly take place following harmful algal bloom (HAB) events, commonly referred to as "Florida red tide" (given that blooms are more commonplace along the coasts of Florida and Texas, especially during late summer and early fall). Algal blooms are a naturally-occurring phenomenon, however their frequency has been increasing in recent decades at least in-part due to human activities, climate changes, and the eutrophication (over-abundance of plant nutrients as a result of agricultural runoff, deforestation, river bed erosion, etc.) of marine waters. HABs have been occurring for all of documented history, evidenced by the Native Americans' understanding of the dangers of shellfish consumption during periods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harmful Algal Bloom
A harmful algal bloom (HAB), or excessive algae growth, sometimes called a red tide in marine environments, is an algal bloom that causes negative impacts to other organisms by production of natural algae-produced toxins, water deoxygenation, mechanical damage to other organisms, or by other means. HABs are sometimes defined as only those algal blooms that produce toxins, and sometimes as any algal bloom that can result in severely lower oxygen levels in natural waters, killing organisms in marine or fresh waters. Blooms can last from a few days to many months. After the bloom dies, the microbes that decompose the dead algae use up more of the oxygen, generating a " dead zone" which can cause fish die-offs. When these zones cover a large area for an extended period of time, neither fish nor plants are able to survive. It is sometimes unclear what causes specific HABs as their occurrence in some locations appears to be entirely natural, while in others they appear to be a re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amnesic Shellfish Poisoning
Amnesic shellfish poisoning (ASP) is an illness caused by consumption of shellfish that contain the marine biotoxin called domoic acid. In mammals, including humans, domoic acid acts as a neurotoxin Neurotoxins are toxins that are destructive to nervous tissue, nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insult (medical), insultsSpencer 2000 that can adversely affect function ..., causing permanent short-term memory loss, brain damage, and death in severe cases. This toxin is produced naturally by marine diatoms belonging to the genus ''Pseudo-nitzschia'' and the species ''Nitzschia navis-varingica''. When accumulated in high concentrations by shellfish during filter feeding, domoic acid can then be passed on to birds, marine mammals, and humans by consumption of the contaminated shellfish. Although human illness due to domoic acid has only been associated with shellfish, the toxin can bioaccumulation, bioaccum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydration
In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers. Most people can tolerate a 3-4% decrease in total body water without difficulty or adverse health effects. A 5-8% decrease can cause fatigue and dizziness. Loss of over 10% of total body water can cause physical and mental deterioration, accompanied by severe thirst. Death occurs with a 15 and 25% loss of body water.Ashcroft F, Life Without Water in Life at the Extremes. Berkeley and Los Angeles, 2000, 134-138. Mild dehydration usually resolves with oral rehydration, but severe cases may need intravenous fluids. Dehydration can cause hypernatremia (high levels of sodium ions in the blood). This is distinct from hypovolemia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Okadaic Acid
Okadaic acid, C44H68O13, is a toxin produced by several species of dinoflagellates. It is known to accumulate in both marine sponges and shellfish. One of the primary causes of diarrhetic shellfish poisoning, okadaic acid is a potent inhibitor of specific protein phosphatases, and has a variety of negative effects on cells. A polyketide, polyether derivative of a C38 fatty acid, okadaic acid and other members of its family have illuminated many biological processes both with respect to dinoflagellate polyketide synthesis as well as the role of protein phosphatases in cell growth. History As early as 1961, reports of gastrointestinal disorders following the consumption of cooked mussels appeared in both the Netherlands and Los Lagos. Attempts were made to determine the source of the symptoms; however, they failed to elucidate the true culprit, instead implicating a species of microplanctonic dinoflagellates. In the summers of the late 1970s, a series of food poisoning outbrea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paralytic Shellfish Poisoning
Paralytic shellfish poisoning (PSP) is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks (such as mussels, clams, oysters and scallops). These shellfish are filter feeders and accumulate neurotoxins, chiefly saxitoxin, produced by microscopic algae, such as dinoflagellates, diatoms, and cyanobacteria. Dinoflagellates of the genus '' Alexandrium'' are the most numerous and widespread saxitoxin producers and are responsible for PSP blooms in subarctic, temperate, and tropical locations. The majority of toxic blooms have been caused by the morphospecies '' Alexandrium catenella, Alexandrium tamarense'', '' Gonyaulax catenella'' and '' Alexandrium fundyense'', which together comprise the ''A. tamarense'' species complex. In Asia, PSP is mostly associated with the occurrence of the species ''Pyrodinium bahamense''. Some pufferfish, including the chamaeleon puffer, also contain saxitoxin, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vomiting
Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pregnancy, motion sickness, or hangover; or it can be an after effect of diseases such as brain tumors, elevated intracranial pressure, or overexposure to ionizing radiation. The feeling that one is about to vomit is called nausea; it often precedes, but does not always lead to vomiting. Impairment due to alcohol or anesthesia can cause inhalation of vomit. In severe cases, where dehydration develops, intravenous fluid may be required. Antiemetics are sometimes necessary to suppress nausea and vomiting. Self-induced vomiting can be a component of an eating disorder such as bulimia nervosa, and is itself now classified as an eating disorder on its own, purging disorder. Complications Aspiration Vomiting is dangerous if gastric content e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 definitions of nausea were proposed in a 2011 book on the topic. Nausea is a non-specific symptom, which means that it has many possible causes. Some common causes of nausea are gastroenteritis and other gastrointestinal disorders, food poisoning, motion sickness, dizziness, migraine, fainting, low blood sugar, anxiety, hyperthermia, dehydration and lack of sleep. Nausea is a side effect of many medications including chemotherapy, or morning sickness in early pregnancy. Nausea may also be caused by disgust and depression. Medications taken to prevent and treat nausea and vomiting are called antiemetics. The most commonly prescribed antiemetics in the US are promethazine, metoclopramide, and the newer ondansetron. The word na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
