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For other uses, see Leech (disambiguation). Look up leech in Wiktionary, the free dictionary. ...
| Leeches |
A Leech on stones | | Scientific classification | | | | Orders | | Arhynchobdellida or Rhynchobdellida
There is some dispute as to whether Hirudinea should be a class itself, or a subclass of the Clitellata. Download high resolution version (1278x1704, 957 KB) Wikipedia does not have an article with this exact name. ...
Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ...
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Classes and subclasses Class Polychaeta (paraphyletic?) Class Clitellata Oligochaeta - Earthworms and others Acanthobdellida Branchiobdellida Hirudinea - Leeches Class Myzostomida Class Archiannelida (polyphyletic) Class Echiura *Some authors consider the subclasses under Clitellata to be classes The annelids, collectively called Annelida, are a large phylum of animals, comprising the segmented worms, with about...
Clitellata is a Class of Annelid worms. ...
Jean-Baptiste Lamarck. ...
This is a leech used primarily in a medicinal format. ...
| Leeches are annelids comprising the subclass Hirudinea. There are fresh water, terrestrial and marine leeches. Like their near relatives, the Oligochaeta, they share the presence of a clitellum. Like earthworms, leeches are hermaphrodites. The medicinal leech, Hirudo medicinalis, which is native to Europe, and its congeners have been used for clinical bloodletting for thousands of years. Classes and subclasses Class Polychaeta (paraphyletic?) Class Clitellata* Oligochaeta - earthworms, etc. ...
This Tree of Life article needs to be cleaned up to conform to a higher standard of quality. ...
In earth worms and other annelids, the Clitellum is a thickened glandular section of the body wall that secretes a viscid sac in which the eggs are deposited. ...
The 1st-century BC sculpture The Reclining Hermaphrodite, in the Museo Nazionale Romano, Palazzo Massimo Alle Terme in Rome A hermaphrodite is an organism that possesses both male and female sex organs during its life. ...
Binomial name Hirudo medicinalis Linnaeus, 1758 In medieval and early modern medicine, the medicinal leech (Hirudo medicinalis and its congeners Hirudo verbana, Hirudo troctina and Hirudo orientalis) was used to remove blood from a patient as part of a process to balance the humors that, according to Hippocrates, must be...
A congener (from Latin roots meaning born together or within the same race or kind) has several different meanings depending on the field in which it is used. ...
Ancient Greek painting in a vase, showing a physician (iatros) bleeding a patient. ...
All leech species are carnivorous. Some are predatory, feeding on a variety of invertebrates such as worms, snails, insect larvae, crustaceans, while a very few are haemophagic parasitic blood-sucking leeches, feeding on the blood of vertebrates such as amphibians, reptiles, waterfowl, fish, and mammals (including humans). The most important predators of leeches are fish, aquatic insects, crayfish and other leeches specialized for predation on leeches. This article deals with meat-eating animals. ...
This snapping turtle is trying to make a meal of a Canada goose, but the goose is too wary. ...
An Anopheles stephensi mosquito obtaining a blood meal from a human host through its pointed proboscis. ...
Low Temperature Scanning Electron Microscope (LTSEM) image of Varroa destructor on a honey bee host Mites parasitising a harvestman Parasitism is one version of symbiosis (living together), a phenomenon in which two organisms which are phylogenetically unrelated co-exist over a prolonged period of time, usually the lifetime of one...
Aquatic Insects live some portion of their life cycle in the water. ...
Families Astacoidea Astacidae Cambaridae Parastacoidea Parastacidae Crayfish, often referred to as crawfish or crawdad, are freshwater crustaceans resembling small lobsters, to which they are closely related. ...
Haemophagic leeches attach to their hosts and remain there until they become full, at which point they fall off to digest. Leeches' bodies are composed of 34 segments. They all have an anterior (oral) sucker formed from the first six segments of their body, which is used to connect to a host for feeding, and can also release an anesthetic to prevent the host from noticing the leech. They use a combination of mucus and suction (caused by concentric muscles in those six segments) to stay attached and secrete an anti-clotting enzyme into the host's blood stream. Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ...
Some species of leech will nurture their young, providing food, transport, and protection, which is unusual behavior in an invertebrate.
Phylogeny
The leeches are presumed to have evolved from the Oligochaeta, most of which feed on detritus. However, some species in the Lumbriculidae are predaceous and have similar adaptations to the leeches. This Tree of Life article needs to be cleaned up to conform to a higher standard of quality. ...
In biology, detritus is organic waste material from decomposing dead plants or animals. ...
The lumbriculidae are a family of microdrile oligochaetes common in fresh-water environments. ...
True leeches, of the subclass Euhirudinea, with both anterior and posterior suckers, are divided into two groups:
- Rhynchobdellae: "jawless" leeches, armed with a muscular straw-like proboscis puncturing organ in a retractable sheath. The Rhynchobdellae consist of two families: The Glossiphoniidae (flattened leeches with a poorly defined anterior sucker) and the Piscicolidae (have cylindrical bodies and a usually well-marked, bell-shaped, anterior sucker). The Glossiphoniidae live in fresh-water habitats; the Pisciolidae are found in sea-water habitats.
- Arhynchobdellids: Leeches which lack a proboscis and which may or may not have jaws armed with teeth. Arhynchobdellids are divided into two orders: Gnathobdellae and Pharyngobdellae
- Gnathobdellae: In this order of "jawed" leeches, armed with teeth, is found the quintessential leech: the European medical (bloodsucking) leech, Hirudo medicinalis. It has a tripartite jaw filled with hundreds of tiny sharp teeth. The incision mark left on the skin by the European medical leech is an inverted Y inside a circle. Its North American counterpart is Macrobdella decora, a much less efficient medical leech. Within this order, the family Hirudidae is characterized by aquatic leeches and the family Haemadipsidae by terrestrial leeches. In the latter are Haemadipsa sylvestris, the Indian leech and Haemadipsa zeylanica(Yamabiru), the Japanese Mountain or Land leech.
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- Pharyngobdellae: These so called worm-leeches consist of freshwater or amphibious leeches that have lost the ability to penetrate a host's tissue and suck blood. They are carnivorous and equipped with a relatively large, toothless, mouth to ingest worms or insect larvae, which are swallowed whole.
The Pharyngobdellae have six to eight pairs of eyes, as compared with five pairs in Gnathobdelliform leeches, and include three related families. The Erpobdellidae are some species from freshwater habitats. For the village on the Isle of Wight, see Freshwater, Isle of Wight. ...
Genera Dinobdella Haemadipsa Haemopis Hirudinaria Hirudo Limnatis Macrobdella Theromyzon Gnathobdellids, or jawed leeches, are a group of leeches with 2 to 3 jaws containing small sharp teeth. ...
Use of Hirudo medicinalis in medicine The leech has long been used in medicine, previously being used to remove poison from the human body, although today its use is mainly limited in limb reattachment procedures instead of the wide-ranging medical use in the past. Leeches have proven highly effective at preventing venous congestion after the surgical re-attachment of fingers, toes, ears and other parts of the body. The word leech either comes directly from or was influenced by the Old English word for "physician", lǣce, which is related to Old High German lāhhi and Old Irish liaig. In geology, a vein is a regularly shaped and lengthy occurrence of an ore; a lode. ...
Congestion is a state of excessive accumulation or overfilling or overcrowding. ...
For the network protocol, see finger protocol. ...
Toes are the digits of the foot of a human or animal. ...
For an alternative meaning, see ear (botany). ...
Old English (also called Anglo-Penis[1], Englisc by its speakers) is an early form of the English language that was spoken in parts of what is now England and southern Scotland between the mid-fifth century and the mid-twelfth century. ...
The (Late Old High) German speaking area of the Holy Roman Empire around 950. ...
Old Irish is the name given to the oldest form of the Irish language which can be, more or less, fully reconstructed from extant sources. ...
Leech saliva contains a number of compounds which assist in its feeding. An anaesthetic limits the sensations felt by the host (and thus reduces the chance of the host trying to detach the leech). A vasodilator causes the blood vessels near the leech to become dilated, and thus provide the leech with a better supply. Anesthesia (AE), also anaesthesia (BE), is the process of blocking the perception of pain and other sensations. ...
Vasodilation is where blood vessels in the body become wider following the relaxation of the smooth muscle in the vessel wall. ...
f you all The blood vessels are part of the circulatory system and function to transport blood throughout the body. ...
Lastly, the leech saliva contains a peptide called hirudin, which is a highly effective anticoagulant. The leech needs this to prevent blood clots (which would block its feeding) from forming in the wound created by its mouthparts. These properties are difficult to achieve using other medical techniques, and it is for this reason that leeches have come back into clinical practice in the last 25 years. Peptides (from the Greek πεπτος, digestible), are the family of short molecules formed from the linking, in a defined order, of various α-amino acids. ...
Hirudin is a naturally ocurring peptide in the salivary glands of medicinal leeches (Hirudo medicinalis) that has a blood anticoagulant property. ...
A thrombus is the final product of blood coagulation, through the aggregation of platelets and the activation of the humoral coagulation system. ...
Because of the minuscule amounts of hirudin present in leeches, it is impractical to harvest the substance for widespread medical use. Hirudin (and related substances) are synthesised using recombinant techniques. Recombinant proteins are proteins that are produced by different genetically modified organisms following insertion of the relevant DNA into their genome. ...
The anatomy of medicinal leeches The anatomy of medicinal leeches may look simple, but more details are found beyond the macro level. Externally, medicinal leeches tend to have a brown and red striped design on an olive colored background. These organisms have two suckers, one at each end, called the anterior and posterior sucker. The posterior is mainly used for leverage while the anterior sucker, consisting of the jaw and teeth, is where the feeding takes place. Medicinal leeches have three jaws--tripartite-- that look like little saws, and on them are about 100 sharp teeth used to incise the host. The incision leaves a mark which is an inverted Y inside of a circle.
Reproduction Leeches are hermaphrodites, meaning they are organisms that have both female and male reproductive organs (ovaries and testes respectively). They also use clitellums to hold the eggs. The 1st-century BC sculpture The Reclining Hermaphrodite, in the Museo Nazionale Romano, Palazzo Massimo Alle Terme in Rome A hermaphrodite is an organism that possesses both male and female sex organs during its life. ...
This article does not cite any references or sources. ...
// For ovary as part of plants see ovary (plants) An ovary is an egg-producing reproductive organ found in female organisms. ...
Look up testes in Wiktionary, the free dictionary. ...
In earth worms and other annelids, the Clitellum is a thickened glandular section of the body wall that secretes a viscid sac in which the eggs are deposited. ...
Nutrition of leeches
Typical leech found in Malaysian jungle. Starting from the anterior sucker is the jaw, the Pharynx which extends to the crop, which leads to the Intestinum, where it ends at the posterior sucker. The crop is a type of stomach that works like an expandable storage compartment. The crop allows a leech to store blood up to five times its body size; because of this ability to hold blood without the blood decaying, due to bacteria living inside the crop, medicinal leeches only need to feed two times a year. Image File history File linksMetadata No higher resolution available. ...
Image File history File linksMetadata No higher resolution available. ...
The pharynx (plural: pharynges) is the part of the neck and throat situated immediately posterior to the mouth and nasal cavity, and cranial, or superior, to the esophagus, larynx, and trachea. ...
The crop is a thin-walled expanded portion of the alimentary tract used for the storage of food prior to digestion that is found in many animals, including earthworms, leeches, insects, and birds. ...
It was long thought that bacteria in the gut carried on digestion for the leech instead of endogenous enzymes which are very low or absent in the intestine. Relatively recently it has been discovered that all leeches and leech species studied do produce endogenous intestinal exopeptidases which can unlink free terminal-end amino acids, one amino acid monomer at a time, from a gradually unwinding and degrading protein polymer. However, unzipping of the protein can start from either the amino (tail) or carboxyl (head) terminal-end of the protein molecule. It just so happens that the leech exopeptidase (arylamidases), possibly aided by proteases from endosymbiotic bacteria in the intestine, starts from the tail or amino protein, free-end, slowly but progressively removing many hundreds of individual terminal amino acids for resynthesis into proteins that constitute the leech. Since leeches lack endopeptidases, the mechanism of protein digestion can not follow the same sequence as it would in all other animals where exopeptidases act sequentially on peptides produced by the action of endopeptidases. Exopeptidases are especially prominent in the common North American worm-leech Erpobdella punctata. This evolutionary choice of exopeptic digestion in Hirudinea distinguishes these carnivorous clitellates from Oligochaeta. This article does not cite any references or sources. ...
Phenylalanine is one of the standard amino acids. ...
A representation of the 3D structure of myoglobin, showing coloured alpha helices. ...
An exopeptidase is an enzyme that catalyses the removal of an amino acid from the end of a polypeptide chain. ...
Endopeptidase are a type of peptidase, and are contrasted to exopeptidases. ...
An exopeptidase is an enzyme that catalyses the removal of an amino acid from the end of a polypeptide chain. ...
Endopeptidase are a type of peptidase, and are contrasted to exopeptidases. ...
An exopeptidase is an enzyme that catalyses the removal of an amino acid from the end of a polypeptide chain. ...
Deficiency of digestive enzymes (except exopeptidases) but more importantly deficiency of vitamins, B complex for example, in leeches is compensated for by enzymes and vitamins produced by endosymbiotic microflora. In Hrudo medicinalis these supplementary factors are produced by an obligatory symbiotic relationship with a single bacterium species, Aeromonas hydrophila, which maintains itself in pure culture by secreting an antibiotic known to medicine since the 19th century, well before Fleming's 1929 discovery of penicillin. Non-bloodsucking leeches such as E. punctata are host to three bacterial symbionts, Pseudomonas sp., Aeromonas sp., and Klebsiella sp. (a slime producer). The bacteria are passed from parent to offspring in the cocoon as it is formed. Digestive enzymes are enzymes in the alimentary tract that break down food so that the organism can absorb it. ...
Meat Ants harvest Leaf Hoppers for their honey dew. ...
In biology, a pure culture is a population of identical cells originating from a single cell. ...
Penicillin Alexander Fleming was the first to suggest that the Penicillium mould must have an antibacterial substance, and the first to isolate the active substance which he named penicillin, but he was not the first to use its properties. ...
Type species Pseudomonas aeruginosa Species group P. aeruginosa P. alcaligenes P. anguilliseptica P. argentinensis P. borbori P. citronellolis P. flavescens P. mendocina P. nitroreducens P. oleovorans P. pseudoalcaligenes P. resinovorans P. straminea group P. aurantiaca P. aureofaciens P. chlororaphis P. fragi P. lundensis P. taetrolens group P. antarctica P. azotoformans...
Families & Genera Aeromonadaceae Aeromonas Tolumonas Succinivibrionaceae Anerobiospirillum Ruminobacter Succinimonas Succinivibrio The Aeromonadales are an order of Proteobacteria, with six genera in two families. ...
Klebsiella pneumoniae is a gram-negative rod-shaped bacteria, and clinically the most important member of the Klebsiella genus of Enterobacteriaceae. ...
Leech bites
Effects
 A Borneo leech. Note how the leech curls and fattens as it fills with blood. A leech attaches itself when it bites, and it will stay attached until it has had its fill of blood. It has been known to suck all the blood out of its host. Due to an anticoagulant (hirudin) that leeches secrete, bites may bleed more than a normal wound after the leech is removed. The effect of the anticoagulant will wear off several hours after the leech is removed and the wound is cleaned. Image File history File linksMetadata Download high resolution version (2048x1536, 702 KB) Summary Picture of a Borneo leech attached to the authors foot. ...
Image File history File linksMetadata Download high resolution version (2048x1536, 702 KB) Summary Picture of a Borneo leech attached to the authors foot. ...
An anticoagulant is a substance that prevents coagulation; that is, it stops blood from clotting. ...
Hirudin is a naturally ocurring peptide in the salivary glands of medicinal leeches (Hirudo medicinalis) that has a blood anticoagulant property. ...
Secretion is the process of segregating, elaborating, and releasing chemicals from a cell, or a secreted chemical substance or amount of substance. ...
Leeches normally carry parasites in their digestive tract which cannot survive in humans and do not pose a threat. However, bacteria, viruses, and parasites from previous blood sources can survive within a leech for months, and may be retransmitted to humans. A study found both HIV and hepatitis B in African leeches from Cameroon.[1] Upper and Lower gastrointestinal tract The gastrointestinal tract (GI tract), also called the digestive tract, or the alimentary canal, is the system of organs within multicellular animals that takes in food, digests it to extract energy and nutrients, and expels the remaining waste. ...
Species Human immunodeficiency virus 1 Human immunodeficiency virus 2 Human immunodeficiency virus (HIV) is a retrovirus that causes acquired immunodeficiency syndrome (AIDS, a condition in humans in which the immune system begins to fail, leading to life-threatening opportunistic infections). ...
Hepatitis (plural hepatitides) implies injury to liver characterised by presence of inflammatory cells in the liver tissue. ...
Removal One recommended method of removal is using a fingernail to break the seal of the oral sucker at the anterior end (the smaller, thinner end) of the leech, repeating with the posterior end, then flicking the leech away. As the fingernail is pushed along the person's skin against the leech, the suction of sucker's seal is broken, at which point the leech should detach its jaws.[2][3]
A common but medically inadvisable technique to remove a leech is to apply a flame, lit cigarette, salt, or caustic chemical such as alcohol, vinegar, lemon juice, insect repellent, heat rub, or certain carbonated drinks. These cause the leech to regurgitate its stomach contents into the wound and quickly detach. The vomit may carry disease and increases the risk of infection.[2][3][4] Heat rub is the name for a variety of products intended to relieve the pain of fibrositis, lumbago and muscular aches and strains. ...
Simply pulling a leech off by grasping it can also cause regurgitation, and adds risks of further tearing the wound, and leaving parts of the leech's jaw in the wound, which can also increase the risk of infection.
An externally attached leech will detach and fall off on its own when it is satiated on blood, usually in about 20 minutes,[4] while internal attachments, such as nasal passage or vaginal attachments, are likelier to require medical intervention.[5][6]
Treatment After removal or detachment, the wound should be cleaned with soap and water, and bandaged. Bleeding may continue for some time, due to the leech's anti-clotting enzyme. Applying pressure can reduce bleeding, although blood loss from a single bite is not dangerous. The wound normally itches as it heals, but should not be scratched as this may complicate healing and introduce other infections. An antihistamine can reduce itching, and applying a cold pack can reduce pain or swelling. An antihistamine is a drug which serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions, through action at the histamine receptor. ...
Some people suffer severe allergic or anaphylactic reactions from leech bites, and require urgent medical care. Symptoms include red blotches or an itchy rash over the body, swelling away from the bitten area (especially around the lips or eyes), feeling faint or dizzy, and difficulty breathing.[4] Anaphylaxis is an acute systemic (multi-system) and severe Type I Hypersensitivity allergic reaction in humans and other mammals. ...
Prevention There is no guaranteed method of preventing leech bites in leech-infested areas. The most reliable method is to cover exposed skin. The effect of insect repellents is disputed, but it is generally accepted that strong (maximum strength or tropical) insect repellents do help prevent bites. Mosquito on a bottle of herbal mosquito repellent. ...
Leech socks can be helpful in preventing bites when the full body will not be at risk of contact with leeches. Leech socks are pulled over the wearer’s trousers to prevent leeches reaching the exposed skin of the legs and attaching there or climbing towards the torso. The socks are generally a light color that also makes it easier to spot leeches climbing up from the feet and looking for skin to attach to.
There are many home remedies to help prevent leech bites. Many people have a great deal of faith in these methods, but none of them has been proven to have much or any effect. Home remedies include: a dried residue of bath soap, tobacco leaves between the toes, pastes of salt or baking soda, citrus juice, and eucalyptus oil. Diluted Calcium hydroxide may also be used as a repellent, but may be damaging or irritating to the skin. A home remedy is a treatment or cure for a disease or other ailment that employs certain foods or other common household items. ...
Sodium bicarbonate is the chemical compound with the formula NaHCO3. ...
This article is about the plant genus. ...
It has been suggested that Portlandite be merged into this article or section. ...
References - Sawyer, Roy T. 1986. Leech Biology and Behaviour. Vol 1-2. Clarendon Press, Oxford
- ^ Nehili, M., C. Ilk, H. Mehlhorn, K. Ruhnau, W. Dick, M. Njayou. Experiments on the possible role of leeches as vectors of animal and human pathogens: a light and electron microscopy study. (Abstract Only). Parasitology Research. 1994;80(4):277-90, PubMed ID 8073013. Retrieved on 2007-07-28.
- ^ a b The Knowledge: Removing a leech Times Online. 2006-10-15. Retrieved on 2007-07-28.
- ^ a b Scenario Archive, Travel Survival: How to Remove a Leech Worst Case Scenarios. Retrieved on 2007-07-28.
- ^ a b c Victorian Poisons Information Centre: Leeches Victorian Poisons Information Centre. Retrieved on 2007-07-28.
- ^ Ibrahim, Adibah, Hakim Bilal Gharib, and Mohd. Nizar Bidin. An Unusual Cause Of Vaginal Bleeding: A Case Report The Internet Journal of Gynecology and Obstetrics. 2003. Vol. 2, No. 2, ISSN: 1528-8439. Retrieved on 2007-07-28.
- ^ Blood-sucker gets up woman's nose Reuters via ABC News. 2005-04-11. Retrieved on 2007-07-28.
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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 209th day of the year (210th in leap years) in the Gregorian calendar. ...
Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...
is the 288th day of the year (289th in leap years) in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 209th day of the year (210th in leap years) in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 209th day of the year (210th in leap years) in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 209th day of the year (210th in leap years) in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 209th day of the year (210th in leap years) in the Gregorian calendar. ...
Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ...
is the 101st day of the year (102nd in leap years) in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 209th day of the year (210th in leap years) in the Gregorian calendar. ...
See also The Tempest Prognosticator The Tempest Prognosticator, also known as the Leech Barometer, is an invention by George Merryweather in which leeches are used in a barometer. ...
A barometer is an instrument used to measure atmospheric pressure. ...
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