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Trypanosomes
Trypanosomatida is a group of kinetoplastid excavates distinguished by having only a single flagellum. The name is derived from the Greek ''trypano'' (borer) and ''soma'' (body) because of the corkscrew-like motion of some trypanosomatid species. All members are exclusively parasitic, found primarily in insects. A few genera have life-cycles involving a secondary host, which may be a vertebrate, invertebrate or plant. These include several species that cause major diseases in humans. Some trypanosomatida are intracellular parasites, with the important exception of Trypanosoma brucei. Medical importance The three major human diseases caused by trypanosomatids are; African trypanosomiasis (sleeping sickness, caused by ''Trypanosoma brucei'' and transmitted by tsetse flies), South American trypanosomiasis (Chagas disease, caused by '' T. cruzi'' and transmitted by triatomine bugs), and leishmaniasis (a set of trypanosomal diseases caused by various species of ''Leishmania'' tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsetse Fly
Tsetse ( , or ) (sometimes spelled tzetze; also known as tik-tik flies), are large, biting flies that inhabit much of tropical Africa. Tsetse flies include all the species in the genus ''Glossina'', which are placed in their own family, Glossinidae. The tsetse are obligate parasites, which live by feeding on the blood of vertebrate animals. Tsetse have been extensively studied, because of their role in transmitting disease. They have a prominent economic impact in sub-Saharan Africa, as the biological vectors of trypanosomes, causing human and animal trypanosomiasis. Tsetse are multivoltine and long-lived, typically producing about four broods per year, with up to 31 broods over their lifespans. Tsetse can be distinguished from other large flies by two easily-observed features: Primarily, tsetse fold their wings over their abdomens completely when they are resting (so that one wing rests directly on top of the other); Secondly, tsetse also have a long proboscis, extending d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypanosoma Brucei
''Trypanosoma brucei'' is a species of parasitic kinetoplastid belonging to the genus '' Trypanosoma'' that is present in sub-Saharan Africa. Unlike other protozoan parasites that normally infect blood and tissue cells, it is exclusively extracellular and inhabits the blood plasma and body fluids. It causes deadly vector-borne diseases: African trypanosomiasis or sleeping sickness in humans, and animal trypanosomiasis or ''nagana'' in cattle and horses. It is a species complex grouped into three subspecies: ''T. b. brucei'', ''T. b. gambiense'' and ''T. b. rhodesiense''. The first is a parasite of non-human mammals and causes ''nagana'', while the latter two are zoonotic infecting both humans and animals and cause African trpanosomiasis. ''T. brucei'' is transmitted between mammal hosts by an insect vector belonging to different species of tsetse fly (''Glossina''). Transmission occurs by biting during the insect's blood meal. The parasites undergo complex morphological chan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
African Trypanosomiasis
African trypanosomiasis, also known as African sleeping sickness or simply sleeping sickness, is an insect-borne parasitic infection of humans and other animals. It is caused by the species '' Trypanosoma brucei''. Humans are infected by two types, ''Trypanosoma brucei gambiense'' (TbG) and ''Trypanosoma brucei rhodesiense'' (TbR). TbG causes over 98% of reported cases. Both are usually transmitted by the bite of an infected tsetse fly and are most common in rural areas. Initially, the first stage of the disease is characterized by fevers, headaches, itchiness, and joint pains, beginning one to three weeks after the bite. Weeks to months later, the second stage begins with confusion, poor coordination, numbness, and trouble sleeping. Diagnosis is by finding the parasite in a blood smear or in the fluid of a lymph node. A lumbar puncture is often needed to tell the difference between first- and second-stage disease. If the disease is not treated quickly it can lead to death. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypanosoma Cruzi
''Trypanosoma cruzi'' is a species of parasitic euglenoids. Among the protozoa, the trypanosomes characteristically bore tissue in another organism and feed on blood (primarily) and also lymph. This behaviour causes disease or the likelihood of disease that varies with the organism: Chagas disease in humans, dourine and surra in horses, and a brucellosis-like disease in cattle. Parasites need a host body and the haematophagous insect triatomine (descriptions "assassin bug", "cone-nose bug", and "kissing bug") is the major vector in accord with a mechanism of infection. The triatomine likes the nests of vertebrate animals for shelter, where it bites and sucks blood for food. Individual triatomines infected with protozoa from other contact with animals transmit trypanosomes when the triatomine deposits its faeces on the host's skin surface and then bites. Penetration of the infected faeces is further facilitated by the scratching of the bite area by the human or animal host. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoleishmania
''Paleoleishmania'' is an extinct genus of kinetoplastids, a monophyletic group of unicellular parasitic flagellate protozoa. At present it is placed in the family Trypanosomatidae. The genus contains two species, ''Paleoleishmania neotropicum'' and the type species ''Paleoleishmania proterus''. The genus is known from the Albian aged Burmese amber deposits of northern Myanmar and the Burdigalian aged Dominican amber deposits on the island of Hispaniola. Etymology The genus name ''Paleoleishmania'' is derived from the Greek ''paleo'' meaning "old" and ''leishmania'' referencing the modern Leishmaniasis-causing genus ''Leishmania''. All trypanosomes are heteroxenous (requiring more than one obligatory host in order to complete life cycle) or are transmitted through some variation of a vector. ''Paleoleishmania proterus'' The genus was described in 2004 by George Poinar Jr. and Robert Poinar in the journal ''Protist'' from amastigotes, promastigotes and paramastigotes preser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chagas Disease
Chagas disease, also known as American trypanosomiasis, is a tropical parasitic disease caused by ''Trypanosoma cruzi''. It is spread mostly by insects in the subfamily '' Triatominae'', known as "kissing bugs". The symptoms change over the course of the infection. In the early stage, symptoms are typically either not present or mild, and may include fever, swollen lymph nodes, headaches, or swelling at the site of the bite. After four to eight weeks, untreated individuals enter the chronic phase of disease, which in most cases does not result in further symptoms. Up to 45% of people with chronic infections develop heart disease 10–30 years after the initial illness, which can lead to heart failure. Digestive complications, including an enlarged esophagus or an enlarged colon, may also occur in up to 21% of people, and up to 10% of people may experience nerve damage. is commonly spread to humans and other mammals by the bite of a kissing bug. The disease may also be spr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetoplastid
Kinetoplastida (or Kinetoplastea, as a class) is a group of flagellated protists belonging to the phylum Euglenozoa, and characterised by the presence of an organelle with a large massed DNA called kinetoplast (hence the name). The organisms are commonly referred to as "kinetoplastids" or "kinetoplasts" The group includes a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments. Their distinguishing feature, the presence of a kinetoplast, is an unusual DNA-containing granule located within the single mitochondrion associated with the base of the cell's flagellum (the basal body). The kinetoplast contains many copies of the mitochondrial genome. The kinetoplastids were first defined by Bronislaw M. Honigberg in 1963 as the members of the flagellated protozoans. They are traditionally divided into the biflagellate Bodonidae and uniflagellate Trypanosomatidae; the former appears to be para ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypanosomiasis
Trypanosomiasis or trypanosomosis is the name of several diseases in vertebrates caused by parasitic protozoan trypanosomes of the genus ''Trypanosoma''. In humans this includes African trypanosomiasis and Chagas disease. A number of other diseases occur in other animals. African trypanosomiasis, which is caused by either ''Trypanosoma brucei gambiense'' or ''Trypanosoma brucei rhodesiense'', threatens some 65 million people in sub-Saharan Africa, especially in rural areas and populations disrupted by war or poverty. The number of cases has been going down due to systematic eradication efforts: in 1998 almost 40,000 cases were reported but almost 300,000 cases were suspected to have occurred; in 2009, the number dropped below 10,000; and in 2018 it dropped below 1000. Chagas disease causes 21,000 deaths per year mainly in Latin America. Signs and symptoms The tsetse fly bite erupts into a red chancre sore and within a few weeks, the person can experience fever, swollen lymph gla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leishmania
''Leishmania'' is a parasitic protozoan, a single-celled organism of the genus '' Leishmania'' that are responsible for the disease leishmaniasis. They are spread by sandflies of the genus ''Phlebotomus'' in the Old World, and of the genus ''Lutzomyia'' in the New World. At least 93 sandfly species are proven or probable vectors worldwide.WHO (2010) Annual report. Geneva Their primary hosts are vertebrates; ''Leishmania'' commonly infects hyraxes, canids, rodents, and humans. History Members of an ancient genus of the ''Leishmania'' parasite, '' Paleoleishmania'', have been detected in fossilized sand flies dating back to the early Cretaceous period. The first written reference to the conspicuous symptoms of cutaneous leishmaniasis surfaced in the Paleotropics within oriental texts dating back to the 7th century BC (allegedly transcribed from sources several hundred years older, between 1500 and 2000 BC). Due to its broad and persistent prevalence throughout antiquity as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leishmaniasis
Leishmaniasis is a wide array of clinical manifestations caused by parasites of the trypanosome genus '' Leishmania''. It is generally spread through the bite of phlebotomine sandflies, ''Phlebotomus'' and ''Lutzomyia'', and occurs most frequently in the tropics and sub-tropics of Africa, Asia, the Americas, and southern Europe. The disease can present in three main ways: cutaneous, mucocutaneous, or visceral. The cutaneous form presents with skin ulcers, while the mucocutaneous form presents with ulcers of the skin, mouth, and nose. The visceral form starts with skin ulcers and later presents with fever, low red blood cell count, and enlarged spleen and liver. Infections in humans are caused by more than 20 species of ''Leishmania''. Risk factors include poverty, malnutrition, deforestation, and urbanization. All three types can be diagnosed by seeing the parasites under microscopy. Additionally, visceral disease can be diagnosed by blood tests. Leishmaniasis can be par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/ Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma (million years ago). The Albian is preceded by the Aptian and followed by the Cenomanian. Stratigraphic definitions The Albian Stage was first proposed in 1842 by Alcide d'Orbigny. It was named after Alba, the Latin name for River Aube in France. A Global Boundary Stratotype Section and Point (GSSP), ratified by the IUGS in 2016, defines the base of the Albian as the first occurrence of the planktonic foraminiferan '' Microhedbergella renilaevis'' at the Col de Pré-Guittard section, Arnayon, Drôme, France. The top of the Albian Stage (the base of the Cenomanian Stage and Upper Cretaceous Series) is defined as the place where the foram species '' Rotalipora globotruncanoides'' first appears in the stratigraphic column. The Alb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trends In Parasitology
A fad or trend is any form of collective behavior that develops within a culture, a generation or social group in which a group of people enthusiastically follow an impulse for a short period. Fads are objects or behaviors that achieve short-lived popularity but fade away. Fads are often seen as sudden, quick-spreading, and short-lived. Fads include diets, clothing, hairstyles, toys, and more. Some popular fads throughout history are toys such as yo-yos, hula hoops, and fad dances such as the Macarena, floss and the twist. Similar to habits or customs but less durable, fads often result from an activity or behavior being perceived as emotionally popular or exciting within a peer group, or being deemed " cool" as often promoted by social networks.Kornblum (2007), p. 213. A fad is said to "catch on" when the number of people adopting it begins to increase to the point of being noteworthy. Fads often fade quickly when the perception of novelty is gone. Overview The specific n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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