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Studies on Trypanosoma rangeli Tejera 1920: VI. Developmental pattern in the haemolymph of Rhodnius prolixus
A?ez, N.;
Memórias do Instituto Oswaldo Cruz , 1983, DOI: 10.1590/S0074-02761983000400004
Abstract: the morphological sequence of trypanosoma rangeli development in the body cavity of rhodnius prolixus is described. the metacyclic trypanosome is the product of successive division and transformation during the intra and extracellular development in the haemocoele. the significance of the early invasion of t. rangeli into the haemolymph is discussed. the epidemiological importance of the developmental pattern of t. rangeli in the vectors haemolymph and the host-response to the parasite are considered.
Metalloproteases in Trypanosoma rangeli-infected Rhodnius prolixus
Feder, D;Gomes, SAO;Garcia, ES;Azambuja, P;
Memórias do Instituto Oswaldo Cruz , 1999, DOI: 10.1590/S0074-02761999000600011
Abstract: protease activities in the haemolymph and fat body in a bloodsucking insect, rhodnius prolixus, infected with trypanosoma rangeli, were investigated. after sds-polyacrylamide gel electrophoresis containing gelatin as substrate, analysis of zymograms performed on samples of different tissues of controls and insects inoculated or orally infected with short or long epimastigotes of t. rangeli, demonstrated distinct patterns of protease activities: (i) proteases were detected in the haemolymph of insects which were fed on, or inoculated with, short epimastigotes of t. rangeli (39 kda and 33 kda, respectively), but they were not observed in the fat body taken from these insects; (ii) protease was also presented in the fat bodies derived from naive insects or controls inoculated with sterile phosphate-saline buffer (49 kda), but it was not detected in the haemolymph of these insects; (iii) no protease activity was observed in both haemolymph and fat bodies taken from insects inoculated with, or fed on, long epimastigotes of t. rangeli. furthermore, in short epimastigotes of t. rangeli extracts, three bands of the protease activities with apparent molecular weights of 297, 198 and 95 kda were detected while long epimastigotes preparation presented only two bands of protease activities with molecular weights of 297 and 198 kda. the proteases from the insect infected with t. rangeli and controls belong to the class of either metalloproteases or metal-activated enzymes since they are inhibited by 1,10-phenanthroline. the significance of these proteases in the insects infected with short epimastigotes of t. rangeli is discussed in relation to the success of the establishment of infection of these parasites in its vector, r. prolixus.
Metalloproteases in Trypanosoma rangeli-infected Rhodnius prolixus  [cached]
Feder D,Gomes SAO,Garcia ES,Azambuja P
Memórias do Instituto Oswaldo Cruz , 1999,
Abstract: Protease activities in the haemolymph and fat body in a bloodsucking insect, Rhodnius prolixus, infected with Trypanosoma rangeli, were investigated. After SDS-polyacrylamide gel electrophoresis containing gelatin as substrate, analysis of zymograms performed on samples of different tissues of controls and insects inoculated or orally infected with short or long epimastigotes of T. rangeli, demonstrated distinct patterns of protease activities: (i) proteases were detected in the haemolymph of insects which were fed on, or inoculated with, short epimastigotes of T. rangeli (39 kDa and 33 kDa, respectively), but they were not observed in the fat body taken from these insects; (ii) protease was also presented in the fat bodies derived from naive insects or controls inoculated with sterile phosphate-saline buffer (49 kDa), but it was not detected in the haemolymph of these insects; (iii) no protease activity was observed in both haemolymph and fat bodies taken from insects inoculated with, or fed on, long epimastigotes of T. rangeli. Furthermore, in short epimastigotes of T. rangeli extracts, three bands of the protease activities with apparent molecular weights of 297, 198 and 95 kDa were detected while long epimastigotes preparation presented only two bands of protease activities with molecular weights of 297 and 198 kDa. The proteases from the insect infected with T. rangeli and controls belong to the class of either metalloproteases or metal-activated enzymes since they are inhibited by 1,10-phenanthroline. The significance of these proteases in the insects infected with short epimastigotes of T. rangeli is discussed in relation to the success of the establishment of infection of these parasites in its vector, R. prolixus.
Studies on Trypanosoma rangeli Tejera, 1920: V - Developmental pattern in the alimentary canal of Rhodnius prolixus
A?ez, N.;
Memórias do Instituto Oswaldo Cruz , 1983, DOI: 10.1590/S0074-02761983000200006
Abstract: the morphological sequence of trypanosoma rangeli development in the alimentary canal of rhodnius prolixus, is described, with observation made in dissected guts from 6 hours to 45 days post-infection. no metacyclic-forms are produced in the digestive tract at any time, and transmission by the contaminative route must be considered atypical. amastigotes appear to be an essential stage in the development of t. rangeli in the gut of r. prolixus. the epidemiological importance of the developmental pattern of t. rangeli in the vector′s gut is discussed, and its usefulness for aging infection is considered.
Haemolymph and Fat Body Metallo-protease Associated with Enterobacter cloacae Infection in the Bloodsucking Insect, Rhodnius prolixus
Feder, D;Salles, JM;Garcia, ES;Azambuja, P;
Memórias do Instituto Oswaldo Cruz , 1998, DOI: 10.1590/S0074-02761998000600023
Abstract: analysis of zymograms with sds-polyacrilamide gel electrophoresis containing gelatin as substrate, and performed on samples of haemolymph or fat body taken from rhodnius prolixus inoculated or not with enterobacter cloacae, demonstrated distinct patterns of protease activities: (i) in the haemolymph two proteases were induced in insects inoculated with bacteria; (ii) two proteases were detected in the fat bodies derived from non-inoculated controls or insect inoculated with sterile culture medium; (iii) haemolymph and fat body had both the same apparent molecular weights proteases (46 and 56 kda); and (iv) these enzymes were characterized as metallo-proteases. the association of these enzymes in rhodnius infected with bacteria was discussed.
Haemolymph and Fat Body Metallo-protease Associated with Enterobacter cloacae Infection in the Bloodsucking Insect, Rhodnius prolixus  [cached]
Feder D,Salles JM,Garcia ES,Azambuja P
Memórias do Instituto Oswaldo Cruz , 1998,
Abstract: Analysis of zymograms with SDS-polyacrilamide gel electrophoresis containing gelatin as substrate, and performed on samples of haemolymph or fat body taken from Rhodnius prolixus inoculated or not with Enterobacter cloacae, demonstrated distinct patterns of protease activities: (i) in the haemolymph two proteases were induced in insects inoculated with bacteria; (ii) two proteases were detected in the fat bodies derived from non-inoculated controls or insect inoculated with sterile culture medium; (iii) haemolymph and fat body had both the same apparent molecular weights proteases (46 and 56 kDa); and (iv) these enzymes were characterized as metallo-proteases. The association of these enzymes in Rhodnius infected with bacteria was discussed.
Trypanosoma rangeli interactions within the vector Rhodnius prolixus: a mini review
Azambuja, Patrícia;Garcia, Eloi S;
Memórias do Instituto Oswaldo Cruz , 2005, DOI: 10.1590/S0074-02762005000500019
Abstract: this article is an integrative mini review of the research on the interactions between trypanosoma rangeli and the insect vector, rhodnius prolixus. special attention is given to the interactions of these parasites with the gut environment, gut walls, with hemolymph invasion, hemocytes, hemocyte microaggregations, prophenoloxidase-activating system, superoxide, and nitric acid generation and eicosanoid pathways. we described factors affecting vectorial capacity and suggested that t. rangeli may modulate the hemocoelic invasion and the survival of the parasites by overcoming the cellular and humoral defense reactions of the insect vector at different physiological events. the mechanisms of these interactions and their significance for parasite transmission are discussed.
Studies on Trypanosoma rangeli Tejera, 1920: IX. Course of infection in different stages of Rhodnius prolixus
A?ez, N.;Nieves, Elsa;Cazorla, D.;
Memórias do Instituto Oswaldo Cruz , 1987, DOI: 10.1590/S0074-02761987000100001
Abstract: frequent individual observations od different stages of rhodnius prolixus exposed to trypanosoma rangeli, revealed a higher susceptibility to infection in the bugs exposed during the two first instars. the mortality rate in infected bugs was significantly higher than in controls, indicating that the parasite was responsible for the majority of deaths. an analysis of the mortality distribution, per instar, is presented. statistical analysis of deaths among the different infected instars, showed that t. rangeli produces its pathological effect in any stage of r. prolixus independently of its susceptibility to the parasite. the survival to adult decreased in all the infected instar bugs. a significant longer time to reach the adult stage was observed in the infected bugs when compared with controls, excepting for specimens exposed in the third instar. the epidemiological significance of the present results is discussed.
Towards an understanding of the interactions of Trypanosoma cruzi and Trypanosoma rangeli within the reduviid insect host Rhodnius prolixus
Azambuja, Patrícia;Ratcliffe, Norman A.;Garcia, Eloi S.;
Anais da Academia Brasileira de Ciências , 2005, DOI: 10.1590/S0001-37652005000300004
Abstract: this review outlines aspects on the developmental stages of trypanosoma cruzi and trypanosoma rangeli in the invertebrate host, rhodnius prolixus. special attention is given to the interactions of these parasites with gut and hemolymph molecules and the effects of the organization of midgut epithelial cells on the parasite development. the vector insect's permissiveness to t. cruzi, which develops in the vector gut, largely depends on the host nutritional state, the parasite strain and the molecular interactions with trypanolytic compounds, lectins and resident bacteria in the gut. t. rangeli invades the hemocoel and once in the hemolymph, can be recognized and activates the defense system of its insect vector, i.e., the prophenoloxidase system, phagocytosis, hemocyte microaggregation, superoxide and nitric oxide activity and the eicosanoid biosynthesis pathway. taken together, these findings not only provide a better understanding of the interactions parasite - insect vector, but also offer new insights into basic physiological processes involved in the parasites transmission.
Towards an understanding of the interactions of Trypanosoma cruzi and Trypanosoma rangeli within the reduviid insect host Rhodnius prolixus  [cached]
Azambuja Patrícia,Ratcliffe Norman A.,Garcia Eloi S.
Anais da Academia Brasileira de Ciências , 2005,
Abstract: This review outlines aspects on the developmental stages of Trypanosoma cruzi and Trypanosoma rangeli in the invertebrate host, Rhodnius prolixus. Special attention is given to the interactions of these parasites with gut and hemolymph molecules and the effects of the organization of midgut epithelial cells on the parasite development. The vector insect's permissiveness to T. cruzi, which develops in the vector gut, largely depends on the host nutritional state, the parasite strain and the molecular interactions with trypanolytic compounds, lectins and resident bacteria in the gut. T. rangeli invades the hemocoel and once in the hemolymph, can be recognized and activates the defense system of its insect vector, i.e., the prophenoloxidase system, phagocytosis, hemocyte microaggregation, superoxide and nitric oxide activity and the eicosanoid biosynthesis pathway. Taken together, these findings not only provide a better understanding of the interactions parasite - insect vector, but also offer new insights into basic physiological processes involved in the parasites transmission.
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