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Ciguatera
Ciguatera fish poisoning (CFP), also known as ciguatera, is a foodborne illness caused by eating tropical reef fish contaminated with ciguatoxins. Such individual fish are said to be ciguatoxic. Symptoms may include diarrhea, vomiting, numbness, itchiness, dysesthesia, sensitivity to hot and cold, dizziness, and weakness with lethargy. The onset of symptoms varies with the amount of toxin absorbed. If a large quantity of toxins are consumed symptoms may appear within half an hour. If a low amount of toxins are consumed symptoms may take a few days to appear. Diarrhea may last up to four days. Symptoms may last a few weeks to a few months. Heart problems such as slow heart rate and low blood pressure may occur. The specific toxins involved are the ciguatoxins 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 They are originally made by a small marine organism, '' Gambierdiscus toxicus'', that grows on and around coral reefs in tropical and subtropical waters.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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moray Eel
Moray eels, or Muraenidae (), are a family (biology), family of eels whose members are found worldwide. There are approximately 200 species in 15 genera which are almost exclusively Marine (ocean), marine, but several species are regularly seen in brackish water, and a few are found in fresh water. The English name, ''moray'', dates back to the early 17th century, and is believed to be a derivative from Portuguese language, Portuguese , which itself derives from Latin , in turn from Greek language, 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 fin, caudal and anal fins. Most species lack pectoral fin, 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 predator, ambush prey. The body is generally patter ... [...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, invertebra ... [...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. Taxonomy 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 often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciguatoxin
image:ciguatoxin.svg, 300px, class=skin-invert-image, Chemical structure of the ciguatoxin CTX1B Ciguatoxins are a class of toxic Polycyclic compound, 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 seem to 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 arrhythmia, and changing the senses of heat and cold. Such poisoning from ciguatoxins is known as ciguatera. Ciguatoxins are lipophilic, able to cros ... [...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] |
Maitotoxin
Maitotoxin (MTX) is an extremely potent toxin produced by ''Gambierdiscus toxicus'', a dinoflagellate species. Maitotoxin has been shown to be more than one hundred thousand times as potent as VX nerve agent. Maitotoxin is so potent that it has been demonstrated that an intraperitoneal injection of 130 ng/kg was lethal in mice. Maitotoxin was named from the ciguateric fish '' Ctenochaetus striatus''—called "maito" in Tahiti—from which maitotoxin was isolated for the first time. It was later shown that maitotoxin is actually produced by the dinoflagellate ''Gambierdiscus toxicus''. Mechanism of toxicity Maitotoxin activates extracellular calcium channels, leading to an increase in levels of cytosolic Ca2+ ions. The exact molecular target of maitotoxin is unknown, but it has been suggested that maitotoxin binds to the plasma membrane Ca2+ ATPase (PMCA) and turns it into an ion channel, similar to how palytoxin turns the Na+/K+-ATPase into an ion channel. Ultimate ... [...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] |
Foodborne Illness
Foodborne illness (also known as foodborne disease and food poisoning) is any illness resulting from the contamination of food by pathogenic bacteria, viruses, or parasites, 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. While contaminants directly cause some symptoms, many effects of foodborne illness result from the body's immune response to these agents, which can vary significantly between individuals and populations based on prior exposure. Symptoms vary depending on the cause. They often include vomiting, fever, aches, and diarrhea. Bouts of vomiting can be repeated with an extended delay in between. This is 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 microbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grouper
Groupers are a diverse group of marine ray-finned fish in the family Epinephelidae, in the order Perciformes. Groupers were long considered a subfamily of the seabasses in Serranidae, but are now treated as distinct. Not all members of this family are called "groupers". 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 na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropical
The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Geographical zone#Temperate zones, temperate zones of both hemispheres, they cover the middle latitudes from to approximately 35° to 40° north and south. The horse latitudes lie within this range. Subtropical climates are often characterized by hot summers and mild winters with infrequent frost. Most subtropical climates fall into two basic types: humid subtropical climate, humid subtropical (Köppen climate classification: Cfa/Cwa), where rainfall is often concentrated in the warmest months, for example list of regions of China, Southeast China and the Southeastern United States, and Mediterranean climate, dry summer or Mediterranean climate (Köppen climate classification: Csa/Csb), where seasonal rainfall is concentrated in the cooler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slow Heart Rate
Bradycardia, also called bradyarrhythmia, is a resting heart rate under 60 beats per minute (BPM). While bradycardia can result from various pathological processes, it is commonly a physiological response to cardiovascular conditioning or due to asymptomatic type 1 atrioventricular block. Resting heart rates of less than 50 BPM are often normal during sleep in young and healthy adults and athletes. In large population studies of adults without underlying heart disease, resting heart rates of 45–50 BPM appear to be the lower limits of normal, dependent on age and sex. Bradycardia is most likely to be discovered in the elderly, as age and underlying cardiac disease progression contribute to its development. Bradycardia may be associated with symptoms of fatigue, dyspnea, dizziness, confusion, and syncope due to reduced blood flow to the brain. The types of symptoms often depend on the etiology of the slow heart rate, classified by the anatomical location of a dysfunction withi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbivorous
A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat non-vascular autotrophs such as mosses, algae and lichens, but do not include those feeding on decomposed plant matters (i.e. detritivores) or macrofungi (i.e. fungivores). As a result of their plant-based diet, herbivorous animals typically have mouth structures ( jaws or mouthparts) well adapted to mechanically break down plant materials, and their digestive systems have special enzymes (e.g. amylase and cellulase) to digest polysaccharides. Grazing herbivores such as horses and cattles have wide flat- crowned teeth that are better adapted for grinding grass, tree bark and other tougher lignin-containing materials, and many of them evolved rumination or cecotropic behaviors to better extract nutrients from plants. A large per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
