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Free-living amoebae (or "FLA") in the Amoebozoa group are important causes of disease in humans and animals. ''Naegleria fowleri'' is sometimes included in the group "free-living amoebae", and it causes a condition traditionally called primary amoebic meningoencephalitis. However, Naegleria is now considered part of the Excavata, not the Amoebozoa, and is considered to be much more closely related to ''Leishmania'' and ''Trypanosoma''. ==Life cycle== ''Acanthamoeba spp''. and ''Balamuthia mandrillaris'' are opportunistic free-living amoebae capable of causing granulomatous amoebic encephalitis (GAE) in individuals with compromised immune systems. * ''Acanthamoeba spp.'' have been found in soil; fresh, brackish, and sea water; sewage; swimming pools; contact lens equipment; medicinal pools; dental treatment units; dialysis machines; heating, ventilating, and air conditioning systems; mammalian cell cultures; vegetables; human nostrils and throats; and human and animal brain, skin, and lung tissues. * ''B. mandrillaris'' however, has not been isolated from the environment but has been isolated from autopsy specimens of infected humans and animals. Unlike ''N. fowleri'', ''Acanthamoeba'' and ''Balamuthia'' have only two stages, cysts and trophozoites, in their life cycle. No flagellated stage exists as part of the life cycle. The trophozoites replicate by mitosis (nuclear membrane does not remain intact) . The trophozoites are the infective forms and are believed to gain entry into the body through the lower respiratory tract, ulcerated or broken skin and invade the central nervous system by hematogenous dissemination . ''Acanthamoeba spp.'' and ''Balamuthia mandrillaris'' cysts and trophozoites are found in tissue. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Free-living Amoebozoa infection」の詳細全文を読む スポンサード リンク
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