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= = Leaving Steeltown = =
" The Jackson Five " would release a second and final single through Steeltown Records — " We Don 't Have To Be Over 21 ( to Fall in Love ) " . The two singles were to be supported by an eleven track studio album but it was never released . On July 26 , 1968 , the group signed a contract with Motown Records . However ...
= = Rediscovery = =
The master tapes to " Big Boy " were thought to be lost , but in 1994 , Jackson family friend Ben Brown found the tapes in his parents ' kitchen pantry . Brown reissued the record in 1995 , on the Inverted Records label — a week before Michael Jackson 's HIStory album was issued . He also remastered the song , selling...
= Chagas disease =
Chagas disease , also known as American trypanosomiasis , is a tropical parasitic disease caused by the protozoan Trypanosoma cruzi . It is spread mostly by insects known as Triatominae or kissing bugs . The symptoms change over the course of the infection . In the early stage , symptoms are typically either not prese...
T. cruzi is commonly spread to humans and other mammals by the blood @-@ sucking " kissing bugs " of the subfamily Triatominae . These insects are known by a number of local names , including : vinchuca in Argentina , Bolivia , Chile and Paraguay , barbeiro ( the barber ) in Brazil , pito in Colombia , chinche in Cent...
Prevention mostly involves eliminating kissing bugs and avoiding their bites . Other preventative efforts include screening blood used for transfusions . A vaccine has not been developed as of 2013 . Early infections are treatable with the medication benznidazole or nifurtimox . Medication nearly always results in a c...
It is estimated that 7 to 8 million people , mostly in Mexico , Central America and South America , have Chagas disease as of 2013 . In 2006 , Chagas was estimated to result in 12 @,@ 500 deaths per year . Most people with the disease are poor , and most people with the disease do not realize they are infected . Large...
= = Signs and symptoms = =
The human disease occurs in two stages : an acute stage , which occurs shortly after an initial infection , and a chronic stage that develops over many years .
The acute phase lasts for the first few weeks or months of infection . It usually occurs unnoticed because it is symptom @-@ free or exhibits only mild symptoms that are not unique to Chagas disease . These can include fever , fatigue , body aches , muscle pain , headache , rash , loss of appetite , diarrhea , nausea ...
The most recognized marker of acute Chagas disease is called Romaña 's sign , which includes swelling of the eyelids on the side of the face near the bite wound or where the bug feces were deposited or accidentally rubbed into the eye . Rarely , young children , or adults may die from the acute disease due to severe i...
If symptoms develop during the acute phase , they usually resolve spontaneously within three to eight weeks in approximately 90 % of individuals . Although the symptoms resolve , even with treatment the infection persists and enters a chronic phase . Of individuals with chronic Chagas disease , 60 – 80 % will never de...
The symptomatic ( determinate ) chronic stage affects the nervous system , digestive system and heart . About two @-@ thirds of people with chronic symptoms have cardiac damage , including dilated cardiomyopathy , which causes heart rhythm abnormalities and may result in sudden death . About one @-@ third of patients ...
20 % to 50 % of individuals with intestinal involvement also exhibit cardiac involvement . Up to 10 % of chronically infected individuals develop neuritis that results in altered tendon reflexes and sensory impairment . Isolated cases exhibit central nervous system involvement , including dementia , confusion , chroni...
The clinical manifestations of Chagas disease are due to cell death in the target tissues that occurs during the infective cycle , by sequentially inducing an inflammatory response , cellular lesions , and fibrosis . For example , intracellular amastigotes destroy the intramural neurons of the autonomic nervous system...
= = Transmission = =
In Chagas @-@ endemic areas , the main mode of transmission is through an insect vector called a triatomine bug . A triatomine becomes infected with T. cruzi by feeding on the blood of an infected person or animal . During the day , triatomines hide in crevices in the walls and roofs .
The bugs emerge at night , when the inhabitants are sleeping . Because they tend to feed on people 's faces , triatomine bugs are also known as " kissing bugs " . After they bite and ingest blood , they defecate on the person . Triatomines pass T. cruzi parasites ( called trypomastigotes ) in feces left near the site ...
Scratching the site of the bite causes the trypomastigotes to enter the host through the wound , or through intact mucous membranes , such as the conjunctiva . Once inside the host , the trypomastigotes invade cells , where they differentiate into intracellular amastigotes . The amastigotes multiply by binary fission ...
Dense vegetation ( such as that of tropical rainforests ) and urban habitats are not ideal for the establishment of the human transmission cycle . However , in regions where the sylvatic habitat and its fauna are thinned by economic exploitation and human habitation , such as in newly deforested areas , piassava palm ...
T. cruzi can also be transmitted through blood transfusions . With the exception of blood derivatives ( such as fractionated antibodies ) , all blood components are infective . The parasite remains viable at 4 ° C for at least 18 days or up to 250 days when kept at room temperature . It is unclear whether T. cruzi can...
Other modes of transmission include organ transplantation , through breast milk , and by accidental laboratory exposure . Chagas disease can also be spread congenitally ( from a pregnant woman to her baby ) through the placenta , and accounts for approximately 13 % of stillborn deaths in parts of Brazil .
Oral transmission is an unusual route of infection , but has been described . In 1991 , farm workers in the state of Paraíba , Brazil , were infected by eating contaminated food ; transmission has also occurred via contaminated açaí palm fruit juice and garapa . A 2007 outbreak in 103 Venezuelan school children was at...
Chagas disease is a growing problem in Europe , because the majority of cases with chronic infection are asymptomatic and because of migration from Latin America .
= = Diagnosis = =
The presence of T. cruzi is diagnostic of Chagas disease . It can be detected by microscopic examination of fresh anticoagulated blood , or its buffy coat , for motile parasites ; or by preparation of thin and thick blood smears stained with Giemsa , for direct visualization of parasites . Microscopically , T. cruzi c...
Various immunoassays for T. cruzi are available and can be used to distinguish among strains ( zymodemes of T.cruzi with divergent pathogenicities ) . These tests include : detecting complement fixation , indirect hemagglutination , indirect fluorescence assays , radioimmunoassays , and ELISA . Alternatively , diagnos...
= = Prevention = =
There is currently no vaccine against Chagas disease . Prevention is generally focused on decreasing the numbers of the insect that spreads it ( Triatoma ) and decreasing their contact with humans . This is done by using sprays and paints containing insecticides ( synthetic pyrethroids ) , and improving housing and sa...
A yeast trap can be used for monitoring infestations of certain species of triatomine bugs ( Triatoma sordida , Triatoma brasiliensis , Triatoma pseudomaculata , and Panstrongylus megistus ) .
Promising results were gained with the treatment of vector habitats with the fungus Beauveria bassiana .
Targeting the symbionts of Triatominae through paratransgenesis can be done .
A number of potential vaccines are currently being tested . Vaccination with Trypanosoma rangeli has produced positive results in animal models . More recently , the potential of DNA vaccines for immunotherapy of acute and chronic Chagas disease is being tested by several research groups .
Blood transfusion was formerly the second @-@ most common mode of transmission for Chagas disease , but the development and implementation of blood bank screening tests has dramatically reduced this risk in the 21st century . Blood donations in all endemic Latin American countries undergo Chagas screening , and testin...
The US FDA has approved two Chagas tests , including one approved in April 2010 , and has published guidelines that recommend testing of all donated blood and tissue products . While these tests are not required in US , an estimated 75 – 90 % of the blood supply is currently tested for Chagas , including all units col...
= = Management = =
There are two approaches to treating Chagas disease : antiparasitic treatment , to kill the parasite ; and symptomatic treatment , to manage the symptoms and signs of the infection . Management uniquely involves addressing selective incremental failure of the parasympathetic nervous system . Autonomic disease imparted...
= = = Medication = = =
Antiparasitic treatment is most effective early in the course of infection , but is not limited to cases in the acute phase . Drugs of choice include azole or nitro derivatives , such as benznidazole or nifurtimox . Both agents are limited in their capacity to completely eliminate T. cruzi from the body ( parasitologi...
Studies suggest antiparasitic treatment leads to parasitological cure in more than 90 % of infants but only about 60 – 85 % of adults treated in the first year of acute phase Chagas disease . Children aged six to 12 years with chronic disease have a cure rate of about 60 % with benznidazole . While the rate of cure de...
Treatment of chronic infection in women prior to or during pregnancy does not appear to reduce the probability the disease will be passed on to the infant . Likewise , it is unclear whether prophylactic treatment of chronic infection is beneficial in persons who will undergo immunosuppression ( for example , organ tra...
= = = Complications = = =
In the chronic stage , treatment involves managing the clinical manifestations of the disease . For example , pacemakers and medications for irregular heartbeats , such as the anti @-@ arrhythmia drug amiodarone , may be life saving for some patients with chronic cardiac disease , while surgery may be required for meg...
= = Epidemiology = =
Chagas disease affects 8 to 10 million people living in endemic Latin American countries , with an additional 300 @,@ 000 – 400 @,@ 000 living in nonendemic countries , including Spain and the United States . An estimated 41 @,@ 200 new cases occur annually in endemic countries , and 14 @,@ 400 infants are born with c...
The disease is present in 18 countries on the American continents , ranging from the southern United States to northern Argentina . Chagas exists in two different ecological zones . In the Southern Cone region , the main vector lives in and around human homes . In Central America and Mexico , the main vector species l...
Although Triatominae bugs feed on them , birds appear to be immune to infection and therefore are not considered to be a T. cruzi reservoir . Even when colonies of insects are eradicated from a house and surrounding domestic animal shelters , they can re @-@ emerge from plants or animals that are part of the ancient ,...
The primary wildlife reservoirs for Trypanosoma cruzi in the United States include opossums , raccoons , armadillos , squirrels , woodrats , and mice . Opossums are particularly important as reservoirs , because the parasite can complete its life cycle in the anal glands of this animal without having to re @-@ enter t...
Studies on raccoons in the Southeast have yielded infection rates ranging from 47 % to as low as 15 @.@ 5 % . Armadillo prevalence studies have been described in Louisiana , and range from a low of 1 @.@ 1 % to 28 @.@ 8 % . Additionally , small rodents , including squirrels , mice , and rats , are important in the syl...
Chronic Chagas disease remains a major health problem in many Latin American countries , despite the effectiveness of hygienic and preventive measures , such as eliminating the transmitting insects . However , several landmarks have been achieved in the fight against it in Latin America , including a reduction by 72 %...
Screening of donated blood , blood components , and solid organ donors , as well as donors of cells , tissues , and cell and tissue products for T. cruzi is mandated in all Chagas @-@ endemic countries and has been implemented . Approximately 300 @,@ 000 infected people live in the United States , which is likely the ...
= = History = =
The disease was named after the Brazilian physician and epidemiologist Carlos Chagas , who first described it in 1909 . The disease was not seen as a major public health problem in humans until the 1960s ( the outbreak of Chagas disease in Brazil in the 1920s went widely ignored ) . Dr Chagas discovered that the intes...
Chagas named the pathogenic parasite as Trypanosoma cruzi and later that year as Schizotrypanum cruzi , both honoring Oswaldo Cruz , the noted Brazilian physician and epidemiologist who successfully fought epidemics of yellow fever , smallpox , and bubonic plague in Rio de Janeiro and other cities in the beginning of ...
In Argentina , the disease is known as mal de Chagas @-@ Mazza , in honor of Salvador Mazza , the Argentine physician who in 1926 began investigating the disease and over the years became the principal researcher of this disease in the country . Mazza produced the first scientific confirmation of the existence of Tryp...
It has been hypothesized that Charles Darwin might have suffered from Chagas disease as a result of a bite of the so @-@ called great black bug of the Pampas ( vinchuca ) ( see Charles Darwin 's illness ) . The episode was reported by Darwin in his diaries of the Voyage of the Beagle as occurring in March 1835 to the ...
= = Research = =
Several experimental treatments have shown promise in animal models . These include inhibitors of oxidosqualene cyclase and squalene synthase , cysteine protease inhibitors , dermaseptins collected from frogs in the genus Phyllomedusa ( P. oreades and P. distincta ) , the sesquiterpene lactone dehydroleucodine ( DhL )...
Chagas disease has a serious economic impact on the United States and the world . The cost of treatment in the United States alone , where the disease is not indigenous , is estimated to be $ 900 million annually , which includes hospitalization and medical devices such as pacemakers . The global cost is estimated at ...
Megazol in a study seems more active against Chagas than benznidazole but has not been studied in humans . Fexinidazole , an old drug rediscovered for this purpose is being tested in phase 2 clinical trials . A Chagas vaccine ( TcVac3 ) has been found to be effective in mice with plans for studies in dogs . It is hope...
= Diamond stingray =
The diamond stingray ( Dasyatis dipterura ) is a species of stingray in the family Dasyatidae . It is found in the coastal waters of the eastern Pacific Ocean from southern California to northern Chile , and around the Galápagos and Hawaiian Islands . This bottom @-@ dweller generally inhabits sandy or muddy flats nea...
When searching for food , diamond stingrays may form groups of up to hundreds of individuals . It is most active at night and preys mainly on burrowing invertebrates and small bony fishes , which are extracted from the bottom via suction or digging . This species is aplacental viviparous : once the embryos exhaust the...
= = Taxonomy and phylogeny = =
In 1880 , the diamond stingray was described twice by three American ichthyologists : as Dasybatus dipterurus by David Starr Jordan and Charles Henry Gilbert in Proceedings of the United States National Museum , and as Trygon brevis by Samuel Garman in Bulletin of the Museum of Comparative Zoology . Jordan and Gilbert...
The species syntypes were collected from San Diego Bay , California . The specific epithet dipterura is derived from the Latin di ( " two " ) , ptero ( " wing " ) , and ura ( " tail " ) , referring to the fin folds on both sides of its tail . Rat @-@ tailed stingray is a former common name for this species . Lisa Rose...