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Variaciones biológicas de Trypanosoma cruzi (Kinetoplastida:Trypanosomatidae) asociadas con la ingestión de diferentes tipos de sangre por el vector Triatoma dimidiata (Hemiptera: Reduviidae)
CALDERóN-ARGUEDAS,OLGER; CHINCHILLA,MISAEL; GARCíA,FERNANDO; VARGAS,MARIO;
Parasitología latinoamericana , 2003, DOI: 10.4067/S0717-77122003000100001
Abstract: the effect of avian and mouse blood in the gut of triatoma dimidiata (hemiptera: reduviidae) on the biological characteristics of two costarican strains of t. cruzi (tc-2 and tc-4) was evaluated in a murine model. this relationship defined four experimental systems named tc-2 gallina, tc-2 raton, tc-4 gallina and tc-4 raton. parasites from each system were inoculated intraperitonealy in c3h mice and the course of the infections were observed three times a week during 60 days. the observations included parasitemia levels (parasites/mm3), concentration of slender and broad forms, duration of prepatent and patent periods, survival, and cumulated mortality. the infection characteristics in all the systems were similar with parasitemia peaks in the days 23 to 33 post infection and broad forms as the predominant tripomastigote circulating forms in all the systems. some variables such as prepatent and patent periods did not show statistically significant differences (p < 0.05). however, the survival was prolonged in mice that were infected to parasites associated to avian blood. the evolution of the mortality was slower in these systems. the data suggests that the parasite virulence modulation could be related to the particular blood sources in the vectors
Variaciones biológicas de Trypanosoma cruzi (Kinetoplastida:Trypanosomatidae) asociadas con la ingestión de diferentes tipos de sangre por el vector Triatoma dimidiata (Hemiptera: Reduviidae) BIOLOGICAL VARIATIONS OF Trypanosoma cruzi (KINETOPLASTIDA: TRYPANOSOMATIDAE) ASSOCIATED TO THE INGEST OF DIFFERENT KINDS OF BLOOD BY THE VECTOR Triatoma dimidiata (HEMIPTERA: REDUVIIDAE)  [cached]
OLGER CALDERóN-ARGUEDAS,MISAEL CHINCHILLA,FERNANDO GARCíA,MARIO VARGAS
Parasitología latinoamericana , 2003,
Abstract: El efecto de las sangres aviar y murina sobre las características biológicas de dos cepas costa-rricenses de T. cruzi (TC-2 y TC-4) fue evaluado mediante un modelo experimental en el cual se infectaron ratones con parásitos previamente expuestos a estos tipos de sangre en el intestino del vector Triatoma dimidiata (Hemiptera: Reduviidae). La relación que se estableció entre las cepas y los tipos de sangre utilizados permitió definir cuatro sistemas experimentales denomi-nados arbitrariamente TC-2 gallina, TC-ratón, TC-4 gallina y TC-4 ratón. Parásitos de cada sistema fueron inoculados intraperitonealmente en ratones C3H y el progreso de la infección fue registrado tres veces por semana durante un período de 60 días. Las observaciones incluyeron: niveles de parasitemia (parásitos/mm3), concentración de formas gruesas y delgadas, duración de los períodos prepatente, patente y de supervivencia y la mortalidad acumulada. Las características de las infecciones en todos los sistemas fueron similares. Estas mostraron picos de parasitemia entre los días 23 y 33 post infección y las formas gruesas fueron los tripomastigotos san-guíneos predominantes. Algunas variables como los períodos prepatente y patente no mostraron diferencias es significativas (p > 0,05). Sin embargo, el período de supervivencia se vio significa-tivamente prolongado en los ratones infectados con parásitos asociados a sangre aviar (p < 0,05). La evolución de la mortalidad fue menos marcada en estos sistemas. Los datos sugieren la ocurrencia de una modulación en las virulencia parasitaria que podría estar relacionada con el tipo de sangre presente en el insecto vector The effect of avian and mouse blood in the gut of Triatoma dimidiata (Hemiptera: Reduviidae) on the biological characteristics of two costarican strains of T. cruzi (TC-2 and TC-4) was evaluated in a murine model. This relationship defined four experimental systems named TC-2 gallina, TC-2 raton, TC-4 gallina and TC-4 raton. Parasites from each system were inoculated intraperitonealy in C3H mice and the course of the infections were observed three times a week during 60 days. The observations included parasitemia levels (parasites/mm3), concentration of slender and broad forms, duration of prepatent and patent periods, survival, and cumulated mortality. The infection characteristics in all the systems were similar with parasitemia peaks in the days 23 to 33 post infection and broad forms as the predominant tripomastigote circulating forms in all the systems. Some variables such as prepatent and patent periods did not show statis
Influence of Triatoma dimidiata in Modulating the Virulence of Trypanosoma cruzi Mexican Strains  [PDF]
E. Guzman-Marin,M. Jimenez-Coello,M. Puerto-Solis,A. Ortega-Pacheco,K. Y. Acosta-Viana
Interdisciplinary Perspectives on Infectious Diseases , 2012, DOI: 10.1155/2012/328091
Abstract: The epidemiology of Chagas disease is complex. There are different vectors and reservoirs and different clinical manifestations. In order to assess whether the biological behavior of three strains isolated in southeastern Mexico (H4 isolated from human, Z17 isolated from Didelphis sp., and V isolated from T. dimidiata) could be modified during passage through the vector T. dimidiata, the parasitemia curve, the amount of amastigote nests, and mortality of BALB/c infected with blood trypomastigotes of T. cruzi were evaluated. Strains were maintained in continuous passage from mouse to mouse and in animals infected with metacyclic trypomastigotes. The parasitemia curves were significantly different ( ) between mice to mice and triatoma to mice groups in strains H4 and Z17, and was also observed fewer amastigote nests in cardiac tissue ( strain H4 with higher number versus all groups and Z17 between mice to mice and triatoma to mice) 45 days after inoculation. It is concluded that T. dimidiata influences in modulating the virulence of strains of T. cruzi in the region. Further studies of the intestinal tract of the insect in search for some protein molecules involved in regulating may clarify the virulence of the parasite. 1. Introduction American Trypanosomiasis also known as Chagas’ disease remains a public health problem throughout Latin America, where it is estimated that 10 million people are infected with Trypanosoma cruzi (T. cruzi), and other 25 million are at risk to become infected [1]. The causative agent, T. cruzi, has a natural biological pleomorphism with biochemical and molecular differences between isolates, showing great differences in their behavior from both in vitro and in vivo studies that may explain the large variation in the clinical presentations of the disease [2–4]. These differences have been attributed to many causes such as environmental factors, host immunity, virulence, pathogenicity, and passage through various species of vectors and hosts. Those differences need to be characterized from the clinical-epidemiological and clinical-pathological points of view [4–6]. In Mexico, the heterogeneity among the locally isolated strains has been reported, and differences in the onset and severity of the disease in human hosts have been attributed to the susceptibility to infection, to the parasite, and/or vector [7, 8]. In Yucatan, several studies on the biological behavior of isolated T. cruzi strains from human cases and reservoirs have been performed. Entomological, epidemiological aspects, and biological behavior of the vectors
Role of two Triatoma (Hemiptera: Reduviidae: Triatominae) species in the transmission of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) to man in the West Coast of Mexico
Martínez-Ibarra, José Alejandro;Bárcenas-Ortega, Nina Malena;Nogueda-Torres, Benjamín;Alejandre-Aguilar, Ricardo;Lino Rodríguez, Milton;Magallón-Gastélum, Ezequiel;López-Martínez, Víctor;Romero-Nápoles, Jesús;
Memórias do Instituto Oswaldo Cruz , 2001, DOI: 10.1590/S0074-02762001000200001
Abstract: from august 1997 to august 1998, 334 specimens of triatoma longipennis and 62 of t. picturata were collected in four groups of localities placed in the zone from guadalajara, jalisco to tepic, nayarit, in the west coast of mexico. most t. longipennis were collected outdoors (69.2%) while most t. picturata (58.1%) were collected indoors. all collected specimens were examined for trypanosoma cruzi infection, which was detected on 98 (29.3%) t. longipennis and 17 (27.4%) t. picturata. this study confirms the role of t. longipennis and t. picturata as some of the main t. cruzi vectors to humans in mexico. habitation infestation rate with t. longipennis was of 0.09 and with t. picturata was of 0.03 and the predominating ecotopes were pile of blocks, chicken coops, pigsties, wall crawls and beds.
Role of two Triatoma (Hemiptera: Reduviidae: Triatominae) species in the transmission of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) to man in the West Coast of Mexico
Martínez-Ibarra José Alejandro,Bárcenas-Ortega Nina Malena,Nogueda-Torres Benjamín,Alejandre-Aguilar Ricardo
Memórias do Instituto Oswaldo Cruz , 2001,
Abstract: From August 1997 to August 1998, 334 specimens of Triatoma longipennis and 62 of T. picturata were collected in four groups of localities placed in the zone from Guadalajara, Jalisco to Tepic, Nayarit, in the West Coast of Mexico. Most T. longipennis were collected outdoors (69.2%) while most T. picturata (58.1%) were collected indoors. All collected specimens were examined for Trypanosoma cruzi infection, which was detected on 98 (29.3%) T. longipennis and 17 (27.4%) T. picturata. This study confirms the role of T. longipennis and T. picturata as some of the main T. cruzi vectors to humans in Mexico. Habitation Infestation Rate with T. longipennis was of 0.09 and with T. picturata was of 0.03 and the predominating ecotopes were pile of blocks, chicken coops, pigsties, wall crawls and beds.
Commercial coconut palm as an ecotope of Chagas disease vectors in north-eastern Venezuela  [PDF]
A. Morocoima,J. Chique,R. Zavala-Jaspe,Z. Díaz-Bello
Journal of Vector Borne Diseases , 2010,
Abstract: Background & objective: There are few reports of Coccus nucifera (Palmae) infestation by triatomines (Hemiptera, Reduviidae, Triatominae), vectors of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae), the causal agent of American Trypanosomiasis. The aim of this study was to determine if this palm is an appropriate ecotope for Rhodnius prolixus and Triatoma maculata, the main vectors in Venezuela. Methods: Dry and green leaves, humid debris, interfoliaceus meshes and bracts from C. nucifera from north-eastern Venezuela were examined for the presence of triatomines. Samples of the intestinal content of vectors, macerated in isotonic saline solution and haemolymph were examined microscopically for the presence of Trypanosoma spp. The parasites were isolated and characterized using biological parameters and PCR. Triatomine blood meal sources were determined using ELISA. Results: A total of 14 palms were examined in which viable eggs of both species of vectors were found in 13 palms (92.85%). A total of 242 R. prolixus and 144 T. maculata adults were collected, of which 98% of R. prolixus and 70% of T. maculata individuals were infected by T. cruzi (TcI genotype) and 13% of R. prolixus individuals showed a mixed infection with T. rangeli, the other American trypanosome. ELISA testing for possible triatomine blood-meal sources revealed that these vectors are essentially eurytrophic and zoophilic, although R. prolixus also eventually used human blood as a nourishment source. Interpretation & conclusion: The results obtained suggest that C. nucifera is an appropriate vegetal niche for these triatomine species in Venezuela. The presence of this commercial palm may represent a useful environmental bioindicator of risk for Chagas disease.
First Report of Aprostocetus asthenogmus (Hymenoptera: Eulophidae) in South America and Parasitizing Eggs of Triatominae Vectors of Chagas Disease  [PDF]
Claudiney Biral dos Santos,Marcelo Teixeira Tavares,Gustavo Rocha Leite,Adelson Luiz Ferreira,Leonardo de Souza Rocha,Aloísio Falqueto
Journal of Parasitology Research , 2014, DOI: 10.1155/2014/547439
Abstract: We report for the first time the parasitism of eggs of two triatomine Chagas disease vectors, Triatoma infestans and T. vitticeps, by the microhymenopterous parasitoid Aprostocetus asthenogmus. We also describe the first identification of this parasitoid in South America. A. asthenogmus were captured near unparasitized triatomine colonies in the municipality of Vitória, state of Espírito Santo, Brazil, and placed into pots with recently laid triatomine eggs. After 24 days, we observed wasps emerging from T. infestans and T. vitticeps eggs. Several characteristics of this parasitoid species suggest that it could be a potential biological control agent of triatomine species. 1. Introduction Triatominae (Hemiptera, Reduviidae) is a subfamily of hematophagous insects known as “kissing bugs” whose members are principally distributed throughout the Neotropical region [1–3]. Certain triatomine species are responsible for the transmission of Trypanosoma cruzi Chagas, 1909 (Kinetoplastida, Trypanosomatidae)—the etiological agent of Chagas disease, which is one of the most dreaded parasitic diseases of Latin America [4]. Attempts to control T. cruzi transmission began soon after Carlos Chagas’ work in the 1900s. The advent of synthetic insecticides in the 1940s was the first major breakthrough in identifying effective techniques for kissing bug control; the introduction of pyrethroids, a more cost-effective synthetic type of insecticide, was another important advance that occurred in the 1980s [5]. Despite these efforts, high levels of vector-borne transmission still occur in many areas, and several endemic countries had to develop large-scale surveillance and intervention programs [6]. Since the Chagas disease discovery, the biological control of its vectors has been considered [7–10]. However, its application to effective triatomine control in the field is still incipient; little success has been achieved by the use of parasitoid wasps [10], although recent studies with entomopathogenic fungi are promising [11]. Several species clustered in different taxonomic groups might function as triatomine pathogens, predators, or parasitoids [12, 13]. For example, the best-known kissing bug parasitoid Telenomus fariai Lima, 1927 (Hymenoptera, Scelionidae), is able to parasitize the eggs of species in three triatomine genera, Panstrongylus, Rhodnius, and Triatoma [12, 14, 15]. Parasitoid wasps are distributed throughout the world in a variety of environments [16] and usually parasitize the eggs of a wide range of insects, many Triatominae species among them [12]. They are
Influence of Triatoma dimidiata in Modulating the Virulence of Trypanosoma cruzi Mexican Strains  [PDF]
E. Guzman-Marin,M. Jimenez-Coello,M. Puerto-Solis,A. Ortega-Pacheco
Interdisciplinary Perspectives on Infectious Diseases , 2012, DOI: 10.1155/2012/328091
Abstract:
Levantamento da fauna de Triatominae (Hemiptera: Reduviidae) em ambiente domiciliar e infec??o natural por Trypanosomatidae no Estado de Mato Grosso do Sul
Almeida, Paulo Silva de;Ceretti Júnior, Walter;Obara, Marcos Takashi;Santos, Honório Roberto;Barata, José Maria Soares;Faccenda, Odival;
Revista da Sociedade Brasileira de Medicina Tropical , 2008, DOI: 10.1590/S0037-86822008000400010
Abstract: between 2000 and 2004, a survey of triatominae fauna (hemiptera: reduviidae) and examination of natural infection caused by trypanosomatidae in the state of mato grosso do sul, brazil, was conducted. a total of 13,671 specimens were collected. through fauna analysis on the insects that were caught, triatoma sordida was characterized as very abundant, very frequent, constant and dominant. the rates of natural infection with trypanosoma cruzi were 3.2% for panstrongylus geniculatus, 0.6% for rhodnius neglectus and 0.1% for triatoma sordida. nevertheless, the state of mato grosso do sul is free from endemic vector transmission.
Leptoconops nosopheris sp. n. (Diptera: Ceratopogonidae) and Paleotrypanosoma burmanicus gen. n., sp. n. (Kinetoplastida: Trypanosomatidae), a biting midge - trypanosome vector association from the Early Cretaceous
Poinar Jr., George;
Memórias do Instituto Oswaldo Cruz , 2008, DOI: 10.1590/S0074-02762008000500010
Abstract: leptoconops nosopheris sp. n. (diptera: ceratopogonidae) is described from a blood-filled female biting midge in early cretaceous burmese amber. the new species is characterized by a very elongate terminal flagellomere, elongate cerci, and an indistinct spur on the metatibia. this biting midge contained digenetic trypanosomes (kinetoplastida: trypanosomatidae) in its alimentary tract and salivary glands. these trypanosomes are described as paleotrypanosoma burmanicus gen. n., sp. n., which represents the first fossil record of a trypanosoma generic lineage.
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