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José M. C. Ribeiro - One of the best experts on this subject based on the ideXlab platform.
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Exploring the sialome of the blood-sucking bug Rhodnius prolixus.
Insect biochemistry and molecular biology, 2004Co-Authors: José M. C. Ribeiro, John F Andersen, Mário A. C. Silva-neto, Van My Pham, Mark Garfield, Jesus G. ValenzuelaAbstract:Rhodnius prolixus is a Hemiptera that feeds exclusively on vertebrate blood in all life stages. Its salivary glands produce potent pharmacological substances that counteract host hemostasis, including anti-clotting, anti-platelet, and vasodilatory substances. To obtain a further insight into the salivary biochemical and pharmacological complexity of this insect, a cDNA library was randomly sequenced, and salivary gland homogenates were fractionated by HPLC to obtain aminoterminal sequences of abundantly expressed proteins. Results indicate a remarkable expansion of the lipocalin family in Rhodnius salivary glands, among other protein sequences described. A summary of 31 new full length proteins deducted from their mRNA sequence is described, including several new members of the nitrophorin, triabin, and pallidipin families. The electronic version of the complete tables is available at http://www.ncbi.nlm.nih.gov/projects/vectors/Rhodnius_prolixus.
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Salivary thiol oxidase activity of Rhodnius prolixus
Insect biochemistry and molecular biology, 1996Co-Authors: José M. C. RibeiroAbstract:Cysteine and other thiol compounds can accelerate the unloading of nitric oxide (NO) from salivary nitrosyl-nitrophorins of the blood sucking bug Rhodnius prolixus. The dependence of NO unloading on cysteine concentration is biphasic, showing a maximum between 0.5 and 1 mM cysteine. The proposed mechanism of action for the unloading is a series of reactions where cysteine (at low concentrations) reacts with the heme group of nitrophorins to form cystine and superoxide. The superoxide then reacts with NO to form peroxynitrite, which decays to a mixture of nitrite and nitrate anions. At high cysteine concentrations, cysteine is converted to cystine and H2O and thus no removal of NO from nitrophorins is observed. The thiol oxidase activity of Rhodnius nitrophorins is similar to that observed before in plant peroxidases [Pichorner et al., Phytochemistry 31, 3371 (1992)]. The possible physiological significance of this reaction to probing and feeding by R. prolixus is discussed.
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purification and characterization of prolixin s nitrophorin 2 the salivary anticoagulant of the blood sucking bug Rhodnius prolixus
Biochemical Journal, 1995Co-Authors: José M. C. Ribeiro, Jorge A Guimaraes, M SchneiderAbstract:The salivary anticoagulant of the blood-sucking bug Rhodnius prolixus was purified to homogeneity using a protocol consisting of weak cation-exchange, DEAE, hydrophobic-interaction and octadecyl reverse-phase chromatography, yielding a protein with the same N-terminal sequence as nitrophorin 2, one of the four NO haem protein carriers present in the salivary glands of Rhodnius with a molecular mass of 19689 Da [D. Champagne, R.H. Nussenzveig and J.M.C. Ribeiro, (1995) J. Biol. Chem. 270, in the press]. To exclude the possibility of the nitrophorin being a contaminant, another chromatographic protocol was performed, consisting of chromatofocusing followed by strong-cation-exchange chromatography. Again the anticoagulant was eluted with nitrophorin 2. Nitrophorin 2 inhibits coagulation Factor VIII-mediated activation of Factor X and accounts for all the anti-clotting activity observed in Rhodnius salivary glands.
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reversible binding of nitric oxide by a salivary heme protein from a bloodsucking insect
Science, 1993Co-Authors: José M. C. Ribeiro, J M H Hazzard, Roberto Nussenzveig, Donald E Champagne, F A WalkerAbstract:The bloodsucking bug Rhodnius prolixus has a salivary vasodilator, previously characterized as a nitrovasodilator, with salivary smooth muscle-relaxing and antiplatelet activity. Rhodnius salivary glands are bright red owing to the abundance of heme proteins. Electron paramagnetic resonance and optical spectroscopic experiments indicated that the salivary vasodilator is a nitrosylheme protein with an Fe(III) heme that binds nitric oxide (NO) reversibly. Dilution of the protein in neutral pH promoted NO release. This protein thus appears to be the NO carrier that helps R. prolixus to feed on blood.
Gustavo Adolfo Vallejo - One of the best experts on this subject based on the ideXlab platform.
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trypanosoma rangeli un protozoo infectivo y no patogeno para el humano que contribuye al entendimiento de la transmision vectorial y la infeccion por trypanosoma cruzi agente causal de la enfermedad de chagas
Revista de la Academia Colombiana de Ciencias Exactas Físicas y Naturales, 2015Co-Authors: Gustavo Adolfo Vallejo, Yazmin Suarez, Jenny Lorena Olaya, Sneider Alexander Gutierrez, Julio Cesar CarranzaAbstract:Unlike Trypanosoma cruzi, the causative agent of Chagas’ disease, T. rangeli is an infective, non-pathogenic parasite for humans, but pathogenic for vectors from the Rhodnius genus. Several T. rangeli genotypes (KP1+/A, B, KP1-/C, KP1-/D and E) have been described based on kinetoplast DNA (kDNA) polymorphisms, the spliced leader or miniexon, the intergenic transcribed spacer (ITS) and the small ribosomal subunit (SSUrRNA). These are selectively transmitted by two Rhodnius phylogenetic lines, thereby indicating co-evolutionary processes between parasite and vector genotypes. The Robustus line (Rhodnius prolixus, R. robustus and R. neglectus) exclusively transmits the KP1+/A genotype and the Pallescens line (R. pallescens, R. colombiensis and R. ecuadoriensis) only transmits the KP1-/C genotype. Even though little knowledge is available regarding the molecular basis of parasitevector interaction, the present work presents unpublished observations about KP1+/A and KP1-/C genotype ability to complete the life-cycle of some of the 19 Rhodnius species and the detection of trypanolytic factors in R. prolixus, R. robustus and R. neglectus against the KP1-/C genotype and some T. cruzi genotypes. Several advances regarding molecular, transcriptome and genomic studies dealing with T. rangeli are presented and compared to T. cruzi; these are the starting point for understanding the selective vectorial transmission of T. rangeli and T. cruzi, T. rangeli pathogenicity for the vector, as well as T. rangeli inability and T. cruzi ability to invade mammalian cells.
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genetic cytogenetic and morphological trends in the evolution of the Rhodnius triatominae rhodniini trans andean group
PLOS ONE, 2014Co-Authors: Sebastian Diaz, Azael Saldana, Jose E Calzada, Gustavo Adolfo Vallejo, Nicolas Jaramilloo, Francisco Panzera, Ruben Perez, Rosina Fernandez, Omar Triana, Andres GomezpalacioAbstract:The Rhodnius Pacific group is composed of three species: Rhodnius pallescens, R. colombiensis and R. ecuadoriensis, which are considered important vectors of trypanosomes (Trypanosoma cruzi and T. rangeli) infecting humans. This group is considered as a recent trans-Andean lineage derived from the widespread distributed sister taxa R. pictipes during the later uplift of northern Andes mountain range. The widest spread species R. pallescens may be a complex of two divergent lineages with different chromosomal attributes and a particular biogeographical distribution across Central America and Colombia with several southern populations in Colombia occupying the same sylvatic habitat as its sister species R. colombiensis. Although the taxonomy of Rhodnius Pacific group has been well studied, the unresolved phylogenetic and systematic issues are the target of this paper. Here we explore the molecular phylogeography of this species group analyzing two mitochondrial (ND4 and cyt b) and one nuclear (D2 region of ribosomal 28S gene) gene sequences. The molecular analyses suggest an early divergence of the species R. ecuadoriensis and R. colombiensis, followed by a recent expansion of R. pallescens lineages. The phylogenetic relationship between sympatric R. pallescens Colombian lineage and R. colombiensis was further explored using wing morphometry, DNA genome size measurements, and by analyzing chromosomal behavior of hybrids progeny obtained from experimental crosses. Our results suggest that the diversification of the two R. pallescens lineages was mainly influenced by biogeographical events such as (i) the emergence of the Panama Isthmus, while the origin and divergence of R. colombiensis was associated with (ii) the development of particular genetic and chromosomal features that act as isolation mechanisms from its sister species R. pallescens (Colombian lineage). These findings provide new insights into the evolution of the Rhodnius Pacific group and the underlying biological processes that occurred during its divergence.
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sequence analysis of the spliced leader intergenic region sl ir and random amplified polymorphic dna rapd of trypanosoma rangeli strains isolated from Rhodnius ecuadoriensis r colombiensis r pallescens and r prolixus suggests a degree of co evolution
Acta Tropica, 2011Co-Authors: Daniel Alfonso Urrea, Julio Cesar Carranza, Edmundo C Grisard, Felipe Guhl, Cesar Augusto Cubacuba, Claudia Herrera, Alejandra Falla, Omar Trianachavez, Gustavo Adolfo VallejoAbstract:Abstract Spliced leader intergenic region (SL-IR) sequences from 23 Trypanosoma rangeli strains isolated from the salivary glands of Rhodnius colombiensis , R. ecuadoriensis , R. pallescens and R. prolixus and two human strains revealed the existence of 4 genotypes with CA, GT, TA, ATT and GTAT microsatellite repeats and the presence of insertions/deletions (INDEL) and single nucleotide polymorphism (SNP) characterizing each genotype. The strains isolated from the same vector species or the same Rhodnius evolutionary line presented the same genotypes, even in cases where strains had been isolated from vectors captured in geographically distant regions. The dendrogram constructed from the SL-IR sequences separated all of them into two main groups, one with the genotypes isolated from R. prolixus and the other group containing three well defined sub-groups with the genotypes isolated from R. pallescens , R. colombiensis and R. ecuadoriensis . Random amplified polymorphic DNA (RAPD) analysis showed the same two main groups and sub-groups supporting strict T. rangeli genotypes’ association with Rhodnius species. Combined with other studies, these results suggest a possible co-evolutionary association between T. rangeli genotypes and their vectors.
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trypanosoma rangeli genotypes association with Rhodnius prolixus and r pallescens allopatric distribution in central america
Infection Genetics and Evolution, 2009Co-Authors: Fernando Salazaranton, Felipe Guhl, Daniel Alfonso Urrea, Carolina Arevalo, Gabriela Azofeifa, Andrea Urbina, Melissa Blandonnaranjo, Octavio E Sousa, Rodrigo Zeledon, Gustavo Adolfo VallejoAbstract:Abstract Previous kDNA polymorphism-based reports have revealed the existence of two Trypanosoma rangeli genotypes (KP1+ and KP1−): SL and SSU rRNA gene polymorphism-based studies have revealed that five genotypes (A–E) are distributed throughout different Latin-American countries. Some evidence has shown that the genotypes’ biogeographical distribution is associated with sympatric Rhodnius species. 12 T. rangeli isolates from humans and reservoirs from El Salvador, Guatemala, Honduras, Costa Rica and Panama were characterised by kDNA and mini-exon gene intergene spacer analysis and compared to 12 previously characterised isolates from humans and vectors from Colombia, Guatemala, Honduras and Venezuela. Central American isolates corresponded to genotypes called KP1(+) or lineage A and KP1(−) or lineage C. Such dimorphism was corroborated by randomly amplified polymorphic DNA (RAPD) in 22 selected isolates; a dendrogram was thus produced having two defined branches. One branch grouped KP1(−) or lineage C strains isolated from Rhodnius colombiensis (Colombia), humans (Panama), Procyon lotor and Choloepus hoffmanni (Costa Rica). The other group was formed by KP1(+) or lineage A strains isolated from Rhodnius prolixus (Colombia, Venezuela) and humans (El Salvador, Guatemala, Honduras). These results present evidence that both groups infect different mammals (humans, domestic and silvatic animals) having no association with any particular vertebrate species; however, T. rangeli KP1(+) or (A) strains have been isolated in Central America in areas where R. prolixus circulate (Honduras, El Salvador and Guatemala) and KP1(−) or (C) strains have been isolated in areas where Rhodnius pallescens is the main vector (Panama and Costa Rica) indicating a parasite-vector association. The same lineages circulate in Andean countries (Colombia, Venezuela, Ecuador and Peru), KP1+ being associated with members of the prolixus group ( R. prolixus and Rhodnius robustus ) and KP1− with members of the pallescens group ( R. pallescens , R. colombiensis and Rhodnius ecuadoriensis ).
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molecular characterisation of trypanosoma rangeli strains isolated from Rhodnius ecuadoriensis in peru r colombiensis in colombia and r pallescens in panama supports a co evolutionary association between parasites and vectors
Infection Genetics and Evolution, 2005Co-Authors: Daniel Alfonso Urrea, Julio Cesar Carranza, Felipe Guhl, Rodrigo Gurgelgoncalves, C C Cuba, C J Schofield, O Triana, Gustavo Adolfo VallejoAbstract:Abstract We present data on the molecular characterisation of strains of Trypanosoma rangeli isolated from naturally infected Rhodnius ecuadoriensis in Peru, from Rhodnius colombiensis, Rhodnius pallescens and Rhodnius prolixus in Colombia, and from Rhodnius pallescens in Panama. Strain characterisation involved a duplex PCR with S35/S36/KP1L primers. Mini-exon gene analysis was also carried out using TrINT-1/TrINT-2 oligonucleotides. kDNA and mini-exon amplification indicated dimorphism within both DNA sequences: (i) KP1, KP2 and KP3 or (ii) KP2 and KP3 products for kDNA, and 380 bp or 340 bp products for the mini-exon. All T. rangeli strains isolated from R. prolixus presented KP1, KP2 and KP3 products with the 340 bp mini-exon product. By contrast, all T. rangeli strains isolated from R. ecuadoriensis, R. pallescens and R. colombiensis, presented profiles with KP2 and KP3 kDNA products and the 380 bp mini-exon product. Combined with other studies, these results provide evidence of co-evolution of T. rangeli strains associated with different Rhodnius species groups east and west of the Andean mountains.
Jorge A Guimaraes - One of the best experts on this subject based on the ideXlab platform.
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purification and characterization of prolixin s nitrophorin 2 the salivary anticoagulant of the blood sucking bug Rhodnius prolixus
Biochemical Journal, 1995Co-Authors: José M. C. Ribeiro, Jorge A Guimaraes, M SchneiderAbstract:The salivary anticoagulant of the blood-sucking bug Rhodnius prolixus was purified to homogeneity using a protocol consisting of weak cation-exchange, DEAE, hydrophobic-interaction and octadecyl reverse-phase chromatography, yielding a protein with the same N-terminal sequence as nitrophorin 2, one of the four NO haem protein carriers present in the salivary glands of Rhodnius with a molecular mass of 19689 Da [D. Champagne, R.H. Nussenzveig and J.M.C. Ribeiro, (1995) J. Biol. Chem. 270, in the press]. To exclude the possibility of the nitrophorin being a contaminant, another chromatographic protocol was performed, consisting of chromatofocusing followed by strong-cation-exchange chromatography. Again the anticoagulant was eluted with nitrophorin 2. Nitrophorin 2 inhibits coagulation Factor VIII-mediated activation of Factor X and accounts for all the anti-clotting activity observed in Rhodnius salivary glands.
Joao Aristeu Da Rosa - One of the best experts on this subject based on the ideXlab platform.
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Rhodnius spp are differentiated based on the peptide protein profile by matrix assisted laser desorption ionization mass spectrometry and chemometric tools
Analytical and Bioanalytical Chemistry, 2020Co-Authors: Eder Dos Santos Souza, Richard Perosa Fernandes, Wesley Nascimento Guedes, Fabio Neves Dos Santos, Marcos N Eberlin, Norberto Peporine Lopes, Victor Damasceno Padovani, Joao Aristeu Da RosaAbstract:Triatominae are hematophagous insects involved in the transmission of Chagas disease. Among the 19 genera of the subfamily, those with the highest epidemiological importance regarding the dissemination of Trypanosoma cruzi are Panstrongylus, Rhodnius, and Triatoma. Of these three genera, Rhodnius presents the greatest difficulties for specific identification. Thus, there is a need to overcome the difficulties in identifying phenotypes of similar species of this genus. In the present study, the MALDI-TOF MS methodology was used to identify 12 Rhodnius species, among the 21 admitted. The MALDI-TOF MS methodology allowed specific characterization through the identification of peptides and proteins, starting from four different methods of extraction: (A) acetonitrile/formic acid (ACN/AF), (B) acetonitrile/trifluoroacetic acid (ACN/TFA), (C) isopropyl/formic acid (IPA/AF), and (D) methanol/formic acid (MeOH/AF), and four types of MALDI-TOF matrices: α-cyano-4-hydroxycinnamic acid (CHCA), sinapic acid (SA), 6-aza-2-thiothymine (ATT), and 2,6-dihydroxyacetophenone (DHAP). The experiments were performed by combining the four solvents and four matrices to select the best MALDI extraction/matrix. The application of the MALDI-TOF MS technique, through the digital mass spectrometry approach combined with chemometric tools, such as partial least squares-discriminant analysis (PLS-DA), was able to discriminate 12 species of Rhodnius genus, which are difficult to identify using morphological characteristics. Thus, in view of the results obtained, the methodology described in the present article can be applied with speed and efficiency for the discrimination of Triatominae species.
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a new species of Rhodnius from brazil hemiptera reduviidae triatominae
ZooKeys, 2017Co-Authors: Joao Aristeu Da Rosa, Vagner Jose Mendonca, Juliana Damieli Nascimento, Claudia Solano Rocha, Danila Blanco De Carvalho, Hernany H G Justino, Rossana Falcone, Maria Tercilia Vilela De Azeredooliveira, Kaio Cesar Chaboli Alevi, Jader De OliveiraAbstract:A colony was formed from eggs of a Rhodnius sp. female collected in Taquarussu, Mato Grosso do Sul, Brazil, and its specimens were used to describe R. taquarussuensissp. n. This species is similar to R. neglectus, but distinct characters were observed on the head, thorax, abdomen, female external genitalia and male genitalia. Chromosomal differences between the two species were also established.
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differential transcriptome analysis supports Rhodnius montenegrensis and Rhodnius robustus hemiptera reduviidae triatominae as distinct species
PLOS ONE, 2017Co-Authors: Danila Blanco De Carvalho, Heloisa Pinotti, Carlos Congrains, Samira Chahadehlers, Reinaldo Alves De Brito, Joao Aristeu Da RosaAbstract:Chagas disease is one of the main parasitic diseases found in Latin America and it is estimated that between six and seven million people are infected worldwide. Its etiologic agent, the protozoan Trypanosoma cruzi, is transmitted by triatomines, some of which from the genus Rhodnius. Twenty species are currently recognized in this genus, including some closely related species with low levels of morphological differentiation, such as Rhodnius montenegrensis and Rhodnius robustus. In order to investigate genetic differences between these two species, we generated large-scale RNA-sequencing data (consisting of four RNA-seq libraries) from the heads and salivary glands of males of R. montenegrensis and R. robustus. Transcriptome assemblies produced for each species resulted in 64,952 contigs for R. montenegrensis and 70,894 contigs for R. robustus, with N50 of approximately 2,100 for both species. SNP calling based on the more complete R. robustus assembly revealed 3,055 fixed interspecific differences and 216 transcripts with high levels of divergence which contained only fixed differences between the two species. A gene ontology enrichment analysis revealed that these highly differentiated transcripts were enriched for eight GO terms related to AP-2 adaptor complex, as well as other interesting genes that could be involved in their differentiation. The results show that R. montenegrensis and R. robustus have a substantial quantity of fixed interspecific polymorphisms, which suggests a high degree of genetic divergence between the two species and likely corroborates the species status of R. montenegrensis.
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description of Rhodnius marabaensis sp n hemiptera reduviidae triatominae from para state brazil
ZooKeys, 2016Co-Authors: Eder Dos Santos Souza, Juliana Damieli Nascimento, Sueli Gardim, Noe Carlos Barbosa Von Atzingen, Maria Betânia Furtado, Jader De Oliveira, Daniel Pagotto Vendrami, Joao Aristeu Da RosaAbstract:Rhodnius marabaensissp. n. was collected on 12 May 2014 in the Murumuru Environmental Reserve in the city of Maraba, Para State, Brazil. This study was based on previous consultation of morphological descriptions of 19 Rhodnius species and compared to the identification key for the genus Rhodnius. The examination included specimens from 18 Rhodnius species held in the Brazilian National and International Triatomine Taxonomy Reference Laboratory in the Oswaldo Cruz Institute in Rio de Janeiro, Brazil. The morphological characteristics of the head, thorax, abdomen, genitalia, and eggs have been determined. Rhodnius prolixus and Rhodnius robustus were examined in more detail because the BLAST analysis of a cyt-b sequence shows they are closely related to the new species, which also occurs in the northern region of Brazil. The most notable morphological features that distinguish Rhodnius marabaensissp. n. are the keel-shaped apex of the head, the length of the second segment of the antennae, the shapes of the prosternum, mesosternum and metasternum, the set of spots on the abdomen, the male genitalia, the posterior and ventral surfaces of the external female genitalia, and the morphological characteristics of the eggs. Rhodnius jacundaensis Serra, Serra & Von Atzingen (1980) nomen nudum specimens deposited at the Maraba Cultural Center Foundation - MCCF were examined and considered as a synonym of Rhodnius marabaensissp. n.
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study of the external female genitalia of 14 Rhodnius species hemiptera reduviidae triatominae using scanning electron microscopy
Parasites & Vectors, 2014Co-Authors: Joao Aristeu Da Rosa, Vagner Jose Mendonca, Juliana Damieli Nascimento, Sueli Gardim, M Cilense, Jader De Oliveira, Danila Blanco De Carvalho, Heloisa Pinotti, Mara Cristina Pinto, Cleber GalvãoAbstract:Background: Among the vectors of Chagas disease (Hemiptera: Reduviidae:Triatominae), there are eighteen Rhodnius species described and some are difficult to identify. The aim of this article is to contribute to the specific identification of fourteen Rhodnius spp. through morphological characters of the external female genitalia. Methods: Female abdomens were cut transversely. The specimens were then prepared for examination by using scanning electron microscopy. Results: The careful examination of the dorsal, posterior and ventral sides revealed characteristics that allowed the identification of each of the fourteen species. Conclusion: The use of external female genitalia as characteristics are proposed as a tool for specifically identifying Rhodnius species, and an identification key for these species is presented.
Christine A Romana - One of the best experts on this subject based on the ideXlab platform.
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Ecology of Rhodnius robustus Larrousse, 1927 (Hemiptera, Reduviidae, Triatominae) in Attalea palm trees of the Tapajós River Region (Pará State, Brazilian Amazon)
Parasites & Vectors, 2014Co-Authors: Fernando Braga Stehling Dias, Marion Quartier, Lileia Diotaiuti, Guy Mejia, Myriam Harry, Anna Carolina Lustosa Lima, Robert Davidson, Frederic Mertens, Marc Lucotte, Christine A RomanaAbstract:Background The rising number of acute cases of Chagas disease in the State of Pará, reported in the past two decades, has been associated, in part, with the ingestion of juice of local palm tree fruits, mainly açaí berry and bacaba. Near the study area, in Santarém, Pará State, an outbreak of Chagas disease has been notified and investigations suggest the consumption of bacaba juice as the main source of infection with T. cruzi . The purpose of this study is to assess the aspects associated to the ecology of Rhodnius robustus in palm trees of three communities of the Tapajós region, in the State of Pará, Brazil. Methods Palm trees were cut down and dissected to search for triatomines. DNA from triatomines was extracted to investigate natural infection by Trypanosoma cruzi and T. rangeli . For statistical analyzes, data from infestation of palm trees, as well as the rates of natural infection by T. cruzi and T. rangeli were compared by Chi-square test. Triatomine density values were analyzed by the nonparametric Kruskal Wallis test and then comparisons between each pair of variables were made by the Mann–Whitney test assuming a confidence interval of 95%. Results We dissected 136 palm trees, 60 at the end of the rainy period and 76 at the end of the dry period. Seventy-three of them (53.7%) were infested with triatomines and three species were found, namely: Rhodnius robustus , Rhodnius pictipes and Panstrongylus lignarius . We collected 743 triatomines, and R. robustus was predominant (n = 739). The identification of natural infection of the insects by trypanosomatids revealed that 125 triatomines were infected by T. cruzi , 69 by T. rangeli and 14 presented both parasites, indicating the presence of mixed infection in the same vector. Conclusion The results suggest that São Tomé is the community with greater density of triatomines and infestation of palm trees; also, it demonstrates the existence of an intense sylvatic cycle in the region, which demands intensive surveillance to prevent human transmission.
