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Acanthamoebidae
Acanthamoebidae is a family of single-celled eukaryotes within the group Amoebozoa. It gets its name from ''Acanthamoeba'', its best-known member. However, it also includes other species, such as '' Comandonia operculata'' and ''Protacanthamoeba bohemica''. Many kinds of Acanthamoebidae are highly prevalent in the soil and water of a variety of environments. They are similar to Hartmannella, but have differently structured pseudopodia, in regard to the actin microfilaments that comprise them. Its most prominent member, ''Acanthamoeba'', can be potentially pathogenic to humans and animals. It has been described as having a common origin with the Entamoebidae and Dictyosteliida. Structure Members of Acanthamoebidae have a specific form of pseudopodia, dubbed acanthopodia. These acanthopodia are continuously formed and reabsorbed, protrude from every area of the cell’s surface, and are usually, short and fine. An exception would be ''A. astronyxis'' and ''A. comandoni'', in wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luapeleamoeba
''Luapeleamoeba'' is a genus of naked amoebae of the family Acanthamoebidae. Morphology ''Luapeleamoeba'' are uninucleate amoebae that, during locomotion, generate a single broad, hyaline lamellipodium with inferior triangular pseudopodia at the edge directing the movement. Behind the lamellipodium there's a thick region of cytoplasm with granules containing a contractile vacuole usually posterior to the single nucleus. There is a big nucleolus with a diameter at least half of the nucleus' diameter. There is a centrosomal region near the nucleus with a Golgi apparatus, other vesicles, and an electron-dense lamellate microtubule-organizing center, which is visibly smaller and less lamellate than those seen in other acanthamoeboid genera. The amoeba is thickest near the contractile vacuole and the nucleus, and tapers gradually toward the edges, giving the overall appearance of a small shield volcano. The floating form is round, although not smooth. No flagella have been seen. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protacanthamoeba
''Protacanthamoeba'' is a genus of free-living naked amoebae of the family Acanthamoebidae described in 1981. It has been found in associations with mycobacteria in drinking water networks, along with other Acanthamoebidae genera, likely allowing the replication of both environmental and pathogenic mycobacteria. Morphology Members of ''Protacanthamoeba'' are characterized by having slender, flexible and sometimes furcate subpseudopodia originated from a broad, hyaline lobose pseudopodium, as well as having centrospheres in its interior, including a plaque-shaped centriole-like body. Their cysts lack preformed pores or opercula. Taxonomy ''Protacanthamoeba'' contains 3 species: * '' Protacanthamoeba bohemica'' * '' Protacanthamoeba caledonica'' * '' Protacanthamoeba invadens'' (previously ''Acanthamoeba ''Acanthamoeba'' is a genus of amoebae that are commonly recovered from soil, fresh water, and other habitats. ''Acanthamoeba'' has two evolutive forms, the metabolicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dracoamoeba
''Dracoamoeba'' is a free-living genus of discosean amoebae in the family Acanthamoebidae containing the sole species ''Dracoamoeba jomungandri'', discovered in 2016 in moist muddy soil close to the ocean shore at Chincoteague, Virginia (USA). Etymology The generic name ''Dracoamoeba'' comes from the latin “Draco”, meaning “ dragon”, which is what the forms of this amoeba resemble. The specific epithet ''jomungandri'' comes from Jörmungandr, the oceanic sea serpent of norse mythology. Morphology Members of ''Dracoamoeba'' are amoebae with ramose pseudopodia capable of forming one lamellipodium with acanthapodial (i.e. tooth-shaped) subpseudopodia. Pseudopodia of all forms are made up of hyaloplasm, a hyaline cytoplasm that composes the pseudopodia, and are used for locomotion and feeding. Their cell body is made of granuloplasm, a granulose cytoplasm that surrounds the nucleus Nucleus ( : nuclei) is a Latin word for the seed inside a fruit. It most often refers t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuolamoeba
''Vacuolamoeba'' is a monotypic genus of free-living discosean amoebae in the family Acanthamoebidae containing the sole species ''Vacuolamoeba acanthoformis'', discovered in 2016 at high-altitude soil in Tibet. Etymology The generic name ''Vacuolamoeba'' references the large size and prominence of the contractile vacuoles. The specific epithet ''acanthoformis'' comes from the latin "Acantho", meaning "spine", and references the spiny shape of the pseudopodia produced, as well as the species' resemblance to ''Acanthamoeba'' species. Morphology Members of ''Vacuolamoeba'' are irregular amoebae with diversely shaped pseudopodia and an anterior hyaloplasmic lamellipodium free of cytoplasmic inclusions. Their acanthopodial (tooth-shaped) extensions can form from all areas of the cell body. Occasionally, the cells produce filose uroidal extensions in their locomotive form. The cells mostly have one vesicular nucleus with a central nucleolus, although cells with two nuclei have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protacanthamoeba Bohemica
''Protacanthamoeba bohemica'' (or ''Protoacanthamoeba bohemica'')Dykova, I., Veverkova-Fialova, M., Fiala, I. & Dvorakova, H. (2005). ''Protoacanthamoeba bohemica'' sp. n., isolated from the liver of tench '' Tinca tinca'' (Linnaeus, 1758). Acta Protozool 44, 369–376. is a species of Acanthamoebidae Acanthamoebidae is a family of single-celled eukaryotes within the group Amoebozoa. It gets its name from ''Acanthamoeba'', its best-known member. However, it also includes other species, such as '' Comandonia operculata'' and '' Protacanthamoeba .... See also * '' Protoacanthamoeba'' References Discosea Amoebozoa species {{Amoebozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discosea
Discosea is a class of Amoebozoa, consisting of naked amoebae with a flattened, discoid body shape. Members of the group do not produce tubular or subcylindrical pseudopodia, like amoebae of the class Tubulinea. When a discosean is in motion, a transparent layer called ''hyaloplasm'' forms at the leading edge of the cell (see lamelliopodium). In some discoseans, short "subpseudopodia" may be extended from this hyaloplasm, but the granular contents of the cell do not flow into these, as in true pseudopodia. Discosean amoebae lack hard shells, but some, like ''Cochliopodium'' and ''Korotnevella'' secrete intricate organic scales which may cover the upper (dorsal) surface of the cell. No species have flagella or flagellated stages of life. The composition of Discosea is similar to that of the class Flabellinea, proposed by Alexey Smirnov and his collaborators in 2005. However, Discosea is a more comprehensive taxon, including several groups not included in Flabellinea. In 2011, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthamoeba
''Acanthamoeba'' is a genus of amoeboid, amoebae that are commonly recovered from soil, fresh water, and other habitat (ecology), habitats. ''Acanthamoeba'' has two evolutive forms, the metabolically active trophozoite and a dormant, stress-resistant cyst. Trophozoites are small, usually 15 to 25 μm in length and amoeboid in shape. In nature, ''Acanthamoeba'' species are free-living bacterivores, but in certain situations, they can cause infections (acanthamebiasis) in humans and other animals. Distribution ''Acanthamoeba'' spp. are among the most prevalent protozoa found in the environment. They are distributed worldwide, and have been isolated from soil, air, sewage, seawater, chlorinated swimming pools, domestic tap water, bottled water, dental treatment units, hospitals, air-conditioning units, and contact lens cases. Additionally, they have been isolated from human skin, nasal cavities, throats, and intestines, as well as plants and other mammals. Role in disease Diseas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centramoebida
Discosea is a class of Amoebozoa, consisting of naked amoebae with a flattened, discoid body shape. Members of the group do not produce tubular or subcylindrical pseudopodia, like amoebae of the class Tubulinea. When a discosean is in motion, a transparent layer called ''hyaloplasm'' forms at the leading edge of the cell (see lamelliopodium). In some discoseans, short "subpseudopodia" may be extended from this hyaloplasm, but the granular contents of the cell do not flow into these, as in true pseudopodia. Discosean amoebae lack hard shells, but some, like '' Cochliopodium'' and '' Korotnevella'' secrete intricate organic scales which may cover the upper (dorsal) surface of the cell. No species have flagella or flagellated stages of life. The composition of Discosea is similar to that of the class Flabellinea, proposed by Alexey Smirnov and his collaborators in 2005. However, Discosea is a more comprehensive taxon, including several groups not included in Flabellinea. In 2011, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthamoeba Keratitis
''Acanthamoeba'' keratitis (AK) is a rare disease in which amoebae of the genus ''Acanthamoeba'' invade the clear portion of the front (cornea) of the eye. It affects roughly 100 people in the United States each year. ''Acanthamoeba'' are protozoa found nearly ubiquitously in soil and water and can cause infections of the skin, eyes, and central nervous system. Infection of the cornea by ''Acanthamoeba'' is difficult to treat with conventional medications, and AK may cause permanent visual impairment or blindness, due to damage to the cornea or through damage to other structures important to vision. Recently, AK has been recognized as an orphan disease and a funded project, orphan diseases ''Acanthamoeba'' keratitis (ODAK), has tested the effects of a diverse range drugs and biocides on AK. Pathogenesis In the United States, ''Acanthamoeba'' keratitis is nearly always associated with soft contact lens use. ''Acanthamoeba'' spp. is most commonly introduced to the eye by contact l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filopodia
Filopodia (singular filopodium) are slender cytoplasmic projections that extend beyond the leading edge of lamellipodia in migrating cells. Within the lamellipodium, actin ribs are known as ''microspikes'', and when they extend beyond the lamellipodia, they're known as filopodia. They contain microfilaments (also called actin filaments) cross-linked into bundles by actin-bundling proteins, such as fascin and fimbrin. Filopodia form focal adhesions with the substratum, linking them to the cell surface. Many types of migrating cells display filopodia, which are thought to be involved in both sensation of chemotropic cues, and resulting changes in directed locomotion. Activation of the Rho family of GTPases, particularly cdc42 and their downstream intermediates, results in the polymerization of actin fibers by Ena/Vasp homology proteins. Growth factors bind to receptor tyrosine kinases resulting in the polymerization of actin filaments, which, when cross-linked, make up the sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AIDS
Human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV), a retrovirus. Following initial infection an individual may not notice any symptoms, or may experience a brief period of influenza-like illness. Typically, this is followed by a prolonged incubation period with no symptoms. If the infection progresses, it interferes more with the immune system, increasing the risk of developing common infections such as tuberculosis, as well as other opportunistic infections, and tumors which are rare in people who have normal immune function. These late symptoms of infection are referred to as acquired immunodeficiency syndrome (AIDS). This stage is often also associated with unintended weight loss. HIV is spread primarily by unprotected sex (including anal and vaginal sex), contaminated blood transfusions, hypodermic needles, and from mother to child duri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granulomatous Amoebic Encephalitis
Granulomatous amoebic encephalitis (GAE) is a rare, usually fatal, subacute-to-chronic central nervous system disease caused by certain species of free-living amoebae of the genera ''Acanthamoeba'', ''Balamuthia'' and ''Sappinia''. The term is most commonly used with ''Acanthamoeba''. In more modern references, the term "balamuthia amoebic encephalitis" (BAE) is commonly used when ''Balamuthia mandrillaris'' is the cause. Symptoms and signs GAE starts slowly, with symptoms like headache, nausea, dizziness, irritability and a low-grade fever. The CNS symptoms depend on the part of the brain that is infected. Changes in behavior are an important sign. Other CNS signs may include seizures, focal neurologic signs, diplopia (double vision), cranial nerve palsies, ataxia, confusion, and personality changes. Some of the symptoms may mimic glioma (especially brainstem glioma), or other brain diseases, which may hamper timely diagnosis. The symptoms are caused by inflammatory necrosis of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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