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Ciguatera
Ciguatera fish poisoning (CFP), also known simply as ciguatera, is a foodborne illness caused by eating reef fish whose flesh is contaminated with certain toxins. Such individual fish are said to be ciguatoxic. Symptoms may include diarrhea, vomiting, numbness, itchiness, sensitivity to hot and cold, dizziness, and weakness. The onset of symptoms varies with the amount of toxin eaten from half an hour to up to two days. The diarrhea may last for up to four days. Some symptoms typically remain for a few weeks to months. Heart difficulties such as slow heart rate and low blood pressure may also occur. The specific toxins involved are ciguatoxin and maitotoxin. They are originally made by a small marine organism, ''Gambierdiscus toxicus'', that grows on and around coral reefs in tropical and subtropical waters. These are eaten by herbivorous fish which in turn are eaten by larger carnivorous fish. The toxins become more concentrated as they move up the food chain. The fish most oft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reef Fish
Coral reef fish are fish which live amongst or in close relation to coral reefs. Coral reefs form complex ecosystems with tremendous biodiversity. Among the myriad inhabitants, the fish stand out as colourful and interesting to watch. Hundreds of species can exist in a small area of a healthy reef, many of them hidden or well camouflaged. Reef fish have developed many ingenious specialisations adapted to survival on the reefs. Coral reefs occupy less than 1% of the surface area of the world oceans, but provide a home for 25% of all marine fish species. Reef habitats are a sharp contrast to the open water habitats that make up the other 99% of the world oceans. However, loss and degradation of coral reef habitat, increasing pollution, and overfishing including the use of destructive fishing practices, are threatening the survival of the coral reefs and the associated reef fish. Overview Coral reefs are the result of millions of years of coevolution among algae, invertebrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciguatoxin
300px, Chemical structure of the ciguatoxin CTX1B Ciguatoxins are a class of toxic polycyclic polyethers found in fish that cause ciguatera. There are several different chemicals in this class. "CTX" is often used as an abbreviation. * - Ciguatoxin 1 * - Ciguatoxin 2 * - Ciguatoxin 3 * - Ciguatoxin 4B (Gambiertoxin 4b) Toxic effect on humans Ciguatoxins do not harm the fish that carry them, but they are poisonous to humans. They cannot be smelled or tasted and cannot be destroyed by cooking. Rapid testing for this toxin in food is not standard. Some ciguatoxins lower the threshold for opening excitatory voltage-gated sodium channels in the nervous system. Opening a sodium channel causes depolarization, which could sequentially cause paralysis, heart contraction, and changing the senses of heat and cold. Such poisoning from ciguatoxins is known as ciguatera. Ciguatoxins are lipophillic, able to cross the blood brain barrier, and can cause both central and peripheral neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gambierdiscus Toxicus
''Gambierdiscus toxicus'' is a species of photosynthetic unicellular eukaryote belonging to the Alveolata, part of the SAR supergroup. It is a dinoflagellate which can cause the foodborne illness ciguatera, and is known to produce several natural polyethers including ciguatoxin, maitotoxin, gambieric acid, and gambierol. The species was discovered attached to the surface of brown macroalgae. History This species was first described by Adachi, R. & Fukuyo, Y in 1979 using samples collected around Gambier Islands. Which was split into five different species (''Gambierdiscus caribaeus'', ''Gambierdiscus carolinianus'', ''Gambierdiscus carpenteri'', ''Gambierdiscus ruetzleri'' and ''Gambierdiscus toxicus'') according to their morphological characteristic of thecal structure, and the sequence of both D1–D3 and D8–D10 regions in large-subunit rDNA. Distribution This species can be found in tropical and subtropical regions in Pacific Ocean and Indian Ocean. It is ofte ... [...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 of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foodborne Illness
Foodborne illness (also foodborne disease and food poisoning) is any illness resulting from the spoilage of contaminated food by pathogenic bacteria, viruses, or parasites that contaminate food, as well as prions (the agents of mad cow disease), and toxins such as aflatoxins in peanuts, poisonous mushrooms, and various species of beans that have not been boiled for at least 10 minutes. Symptoms vary depending on the cause but often include vomiting, fever, and aches, and may include diarrhea. Bouts of vomiting can be repeated with an extended delay in between, because even if infected food was eliminated from the stomach in the first bout, microbes, like bacteria (if applicable), can pass through the stomach into the intestine and begin to multiply. Some types of microbes stay in the intestine. For contaminants requiring an incubation period, symptoms may not manifest for hours to days, depending on the cause and on quantity of consumption. Longer incubation per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scombroid Food Poisoning
Scombroid food poisoning, also known as simply scombroid, is a foodborne illness that typically results from eating spoiled fish. Symptoms may include flushed skin, headache, itchiness, blurred vision, abdominal cramps, and diarrhea. Onset of symptoms is typically 10 to 60 minutes after eating and can last for up to two days. Rarely, breathing problems or an irregular heartbeat may occur. Scombroid occurs from eating fish high in histamine due to inappropriate storage or processing. Fish commonly implicated include tuna, mackerel, mahi mahi, sardine, anchovy, herring, bluefish, amberjack, and marlin. These fish naturally have high levels of histidine, which is converted to histamine when bacterial growth occurs during improper storage. Subsequent cooking, smoking, or freezing does not eliminate the histamine. Diagnosis is typically based on the symptoms and may be supported by a normal blood tryptase. If a number of people who eat the same fish develop symptoms, the diagnosis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioaccumulation
Bioaccumulation is the gradual accumulation of substances, such as pesticides or other chemicals, in an organism. Bioaccumulation occurs when an organism absorbs a substance at a rate faster than that at which the substance is lost or eliminated by catabolism and excretion. Thus, the longer the biological half-life of a toxic substance, the greater the risk of chronic poisoning, even if environmental levels of the toxin are not very high. Bioaccumulation, for example in fish, can be predicted by models. Hypothesis for molecular size cutoff criteria for use as bioaccumulation potential indicators are not supported by data. Biotransformation can strongly modify bioaccumulation of chemicals in an organism. Toxicity induced by metals is associated with bioaccumulation and biomagnification. Storage or uptake of metals faster than the rate at which an organism metabolizes and excretes lead to the accumulation of that metal. The presence of various chemicals and harmful substance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moray Eel
Moray eels, or Muraenidae (), are a family of eels whose members are found worldwide. There are approximately 200 species in 15 genera which are almost exclusively marine, but several species are regularly seen in brackish water, and a few are found in fresh water. The English name, from the early 17th century, derives from Portuguese , which itself derives from Latin , in turn from Greek , ; these are the Latin and Greek names of the Mediterranean moray. Anatomy The dorsal fin extends from just behind the head along the back and joins seamlessly with the caudal and anal fins. Most species lack pectoral and pelvic fins, adding to their serpentine appearance. Their eyes are rather small; morays rely mostly on their highly developed sense of smell, lying in wait to ambush prey. The body is generally patterned. In some species, the inside of the mouth is also patterned. Their jaws are wide, framing a protruding snout. Most possess large teeth used to tear flesh or grasp slipp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grouper
Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers"; the family also includes the sea basses. The common name "grouper" is usually given to fish in one of two large genera: ''Epinephelus'' and ''Mycteroperca''. In addition, the species classified in the small genera ''Anyperidon'', ''Cromileptes'', ''Dermatolepis'', ''Graciela'', ''Saloptia'', and ''Triso'' are also called "groupers." Fish in the genus ''Plectropomus'' are referred to as "coral groupers." These genera are all classified in the subfamily Epiphelinae. However, some of the hamlets (genus ''Alphestes''), the hinds (genus ''Cephalopholis''), the lyretails (genus ''Variola''), and some other small genera (''Gonioplectrus'', ''Niphon'', ''Paranthias'') are also in this subfamily, and occasional species in other serranid genera have common names involving the word "grouper." Nonetheless, the word "gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barracuda
A barracuda, or cuda for short, is a large, predatory, ray-finned fish known for its fearsome appearance and ferocious behaviour. The barracuda is a saltwater fish of the genus ''Sphyraena'', the only genus in the family Sphyraenidae, which was named by Constantine Samuel Rafinesque in 1815. It is found in tropical and subtropical oceans worldwide ranging from the eastern border of the Atlantic Ocean to the Red Sea, on its western border the Caribbean Sea, and in tropical areas of the Pacific Ocean. Barracudas reside near the top of the water and near coral reefs and sea grasses. Barracudas are targeted by sport-fishing enthusiasts. Etymology The common name "barracuda" is derived from Spanish, with the original word being of possibly Cariban origin. Description Barracuda are snake-like in appearance, with prominent, sharp-edged, fang-like teeth, much like piranha, all of different sizes, set in sockets of their large jaws. They have large, pointed heads with an underb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bradycardia
Bradycardia (also sinus bradycardia) is a slow resting heart rate, commonly under 60 beats per minute (BPM) as determined by an electrocardiogram. It is considered to be a normal heart rate during sleep, in young and healthy or elderly adults, and in athletes. In some people, bradycardia below 60 BPM may be associated with fatigue, weakness, dizziness, sweating, and fainting. The term "relative bradycardia" is used to refer to a heart rate slower than an individual's typical resting heart rate. Athletes may have athletic heart syndrome, which includes bradycardia as part of the cardiovascular adaptations to training and participation. The word "bradycardia" is from the Greek βραδύς ''bradys'' "slow", and καρδία ''kardia'' "heart". Classification Sinus Atrial bradycardias are divided into three types. The first, respiratory sinus arrhythmia, is usually found in young and healthy adults. Heart rate increases during inhalation and decreases during exhalation. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
