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1.
Rev. Soc. Bras. Med. Trop ; 54: e0873-2020, 2021. graf
Article in English | LILACS | ID: biblio-1155567

ABSTRACT

Abstract Chagas disease is caused by the protozoan Trypanosoma cruzi. Seven lineages have been identified based on different molecular markers, namely TcI, TcII, TcIII, TcIV, TcV, TcVI, and TcBat. Dogs play the role of epidemiological sentinels being domestic reservoirs of T. cruzi. The aim of the current study was to report the first case of CD in a domestic dog in Manaus, Amazonas, Brazil, infected with T. cruzi DTU TcIV. We hope our report encourages veterinarians and surveillance professionals to a take a deeper look at T. cruzi infection in domestic animals.


Subject(s)
Animals , Dogs , Trypanosoma cruzi/genetics , Chagas Disease/diagnosis , Chagas Disease/veterinary , Brazil , Genotype
2.
Mem. Inst. Oswaldo Cruz ; 116: e200634, 2021. graf
Article in English | LILACS | ID: biblio-1154876

ABSTRACT

The availability of Trypanosomatid genomic data in public databases has opened myriad experimental possibilities that have contributed to a more comprehensive understanding of the biology of these parasites and their interactions with hosts. In this review, after brief remarks on the history of the Trypanosoma cruzi and Leishmania genome initiatives, we present an overview of the relevant contributions of genomics, transcriptomics and functional genomics, discussing the primary obstacles, challenges, relevant achievements and future perspectives of these technologies.


Subject(s)
Trypanosoma cruzi/genetics , Genome, Protozoan/genetics , Leishmania/genetics , Computational Biology , Genomics
3.
Mem. Inst. Oswaldo Cruz ; 115: e200019, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135223

ABSTRACT

BACKGROUND NME23/NDPKs are well conserved proteins found in all living organisms. In addition to being nucleoside diphosphate kinases (NDPK), they are multifunctional enzymes involved in different processes such as DNA stability, gene regulation and DNA repair among others. TcNDPK1 is the canonical NDPK isoform present in Trypanosoma cruzi, which has nuclease activity and DNA-binding properties in vitro. OBJECTIVES In the present study we explored the role of TcNDPK1 in DNA damage responses. METHODS TcNDPK1 was expressed in mutant bacteria and yeasts and over-expressed in epimastigotes. Mutation frequencies, tolerance to genotoxic agents and activity of DNA repair enzymes were evaluated. FINDINGS Bacteria decreased about 15-folds the spontaneous mutation rate and yeasts were more resistant to hydrogen peroxide and to UV radiation than controls. Parasites overexpressing TcNDPK1 were able to withstand genotoxic stresses caused by hydrogen peroxide, phleomycin and hidroxyurea. They also presented less genomic damage and augmented levels of poly(ADP)ribose and poly(ADP)ribose polymerase, an enzyme involved in DNA repair. MAIN CONCLUSION These results strongly suggest a novel function for TcNDPK1; its involvement in the maintenance of parasite's genome integrity.


Subject(s)
Trypanosoma cruzi/enzymology , DNA Damage , Nucleoside-Diphosphate Kinase/metabolism , Trypanosoma cruzi/genetics , Poly(ADP-ribose) Polymerases , Nucleoside-Diphosphate Kinase/genetics , DNA Repair
4.
Mem. Inst. Oswaldo Cruz ; 115: e200142, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135283

ABSTRACT

BACKGROUND Calpains are present in almost all organisms and comprise a family of calcium-dependent cysteine peptidases implicated in crucial cellular functions. Trypanosoma cruzi, the causative agent of Chagas disease, presents an expansion on this gene family with unexplored biological properties. OBJECTIVES Here, we searched for calpains in the T. cruzi genome, evaluated the mRNA levels, calpain activity and the protein expression and determined the cellular localisation in all three parasite life cycle forms. METHODS/FINDINGS Sixty-three calpain sequences were identified in T. cruzi CL Brener genome, with fourteen domain arrangements. The comparison of calpain mRNA abundance by quantitative polymerase chain reaction (qPCR) revealed seven up-regulated sequences in amastigotes and/or bloodstream trypomastigotes and five in epimastigotes. Western Blotting analysis revealed seven different molecules in the three parasite forms, and one amastigote-specific, while no proteolytic activity could be detected. Flow cytometry assays revealed a higher amount of intracellular calpains in amastigotes and/or trypomastigotes in comparison to epimastigotes. Finally, ultrastructural analysis revealed the presence of calpains in the cytoplasm, vesicular and plasma membranes of the three parasite forms, and in the paraflagellar rod in trypomastigotes. CONCLUSION Calpains are differentially expressed and localised in the T. cruzi life cycle forms. This study adds data on the calpain occurrence and expression pattern in T. cruzi.


Subject(s)
Animals , Trypanosoma cruzi/genetics , Calpain/genetics , RNA, Messenger , Calpain/metabolism , Blotting, Western , Chagas Disease , Life Cycle Stages
5.
Mem. Inst. Oswaldo Cruz ; 115: e190457, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135252

ABSTRACT

BACKGROUND Imitation SWItch (ISWI) ATPase is the catalytic subunit in diverse chromatin remodeling complexes. These complexes modify histone-DNA interactions and therefore play a pivotal role in different DNA-dependent processes. In Trypanosoma cruzi, a protozoan that controls gene expression principally post-transcriptionally, the transcriptional regulation mechanisms mediated by chromatin remodeling are poorly understood. OBJECTIVE To characterise the ISWI remodeler in T. cruzi (TcISWI). METHODS A new version of pTcGW vectors was constructed to express green fluorescent protein (GFP)-tagged TcISWI. CRISPR-Cas9 system was used to obtain parasites with inactivated TcISWI gene and we determined TcISWI partners by cryomilling-affinity purification-mass spectrometry (MS) assay as an approximation to start to unravel the function of this protein. FINDINGS Our approach identified known ISWI partners [nucleoplasmin-like protein (NLP), regulator of chromosome condensation 1-like protein (RCCP) and phenylalanine/tyrosine-rich protein (FYRP)], previously characterised in T. brucei, and new components in TcISWI complex [DRBD2, DHH1 and proteins containing a domain characteristic of structural maintenance of chromosomes (SMC) proteins]. Data are available via ProteomeXchange with identifier PXD017869. MAIN CONCLUSIONS In addition to its participation in transcriptional silencing, as it was reported in T. brucei, the data generated here provide a framework that suggests a role for TcISWI chromatin remodeler in different nuclear processes in T. cruzi, including mRNA nuclear export control and chromatin compaction. Further work is necessary to clarify the TcISWI functional diversity that arises from this protein interaction study.


Subject(s)
Animals , Transcription Factors/genetics , Trypanosoma cruzi/genetics , Adenosine Triphosphatases/genetics , Chromatin Assembly and Disassembly/genetics , Gene Expression Regulation , Blotting, Western , Flow Cytometry
6.
Rev. Soc. Bras. Med. Trop ; 53: e20200189, 2020. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1143863

ABSTRACT

Abstract INTRODUCTION: Knowledge of triatomine bloodmeal sources is essential for understanding vector-host interactions in Trypanosoma cruzi transmission cycles. Expensive commercial deoxyribonucleic acid (DNA) extraction kits are widely used for bloodmeal identification. This study assessed the performance of an inexpensive phenol-chloroform DNA extraction protocol for identification of triatomine bloodmeal sources, comparing it with a commercially available kit. METHODS: Both methods were used to obtain DNA from the intestinal contents of Triatoma brasiliensis blood-fed on either Columba sp., Mus musculus, or Gallus gallus. Subsequently, the mitochondrial 12S ribosomal ribonucleic acid (rRNA) gene was amplified by polymerase chain reaction, sequenced, and compared with GenBank data. RESULTS: Twelve (80%) samples extracted with the commercial kit and four (26.7%) with phenol-chloroform were pure (according to the A260/A280 ratio). Samples extracted with phenol-chloroform, except for Columba sp. samples, had higher DNA concentration than those extracted with the commercial kit. Samples extracted using phenol-chloroform and blood-fed on G. gallus had significantly higher DNA concentration than those blood-fed on Columba sp. (p-value <0.001) and M. musculus (p-value <0.001). The 215-base-pair 12S rRNA fragment was amplified from all samples and produced reliable sequences, enabling the identification of the bloodmeal source, most of which showed identity and coverage above 95%. The phenol-chloroform method was much less expensive than the commercial kit but took considerably more time to perform. CONCLUSIONS: Our data showed that both DNA extraction methods produced reliable sequences enabling identification of triatomine bloodmeal sources but differed greatly in cost and time required.


Subject(s)
Animals , Triatoma/genetics , Trypanosoma cruzi/genetics , DNA/genetics , Chloroform , Phenol , Mice
7.
Rev. Soc. Bras. Med. Trop ; 52: e20180541, 2019. tab
Article in English | LILACS | ID: biblio-1057254

ABSTRACT

Abstract INTRODUCTION Chagas disease is a major public health problem that is endemic in Brazil and Latin America. This study aimed to determine the socioeconomic, demographic, and clinical characteristics of 171 patients (mean age, 45 years; female, 65%) with Chagas disease at Hospital Universitário de Brasília, Federal District, Brazil. METHODS We implemented this cross-sectional study using a clinical epidemiological questionnaire, electrocardiography, echocardiography, and quantitative detection of Trypanosoma cruzi DNA in blood using qRT-PCR. RESULTS Among the patients, 26.3% had a full elementary education, and 13.2% were illiterate. Most (63.6%) were economically classified as class C, and 51.5% were born in Bahia state. A total of 62.0% participants reported previous contact with the triatomine bug. The clinical forms of the disease were indeterminate (69.51%), cardiac (15.24%), digestive (10.37%), and mixed (4.88%). The most common electrocardiographic abnormality was complete right bundle branch block in association with a divisional anterosuperior block. Only 14.6% of the patients complied with benznidazole medication for at least 60 days, and 164 of them were assessed by echocardiography. The parasite load was positive in 56% of the patients. CONCLUSIONS: Chagas disease affected mostly women, with the indeterminate chronic form of the disease.


Subject(s)
Humans , Male , Female , Adult , Aged , Young Adult , Trypanosoma cruzi/isolation & purification , Chagas Disease/epidemiology , Socioeconomic Factors , Trypanosoma cruzi/genetics , Brazil/epidemiology , Echocardiography , Cross-Sectional Studies , DNA, Protozoan/genetics , Chagas Disease/parasitology , Parasite Load , Real-Time Polymerase Chain Reaction , Middle Aged
8.
Rev. Soc. Bras. Med. Trop ; 51(4): 445-451, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-957436

ABSTRACT

Abstract INTRODUCTION The National Park of Serra das Confusões (NPSC) is a protected area of natural landscape located in Southern Piauí, Brazil, and it is considered as one of the largest and most important protected areas in the Caatinga biome. METHODS The natural occurrences of trypanosomatids from hemocultures on small mammals and cultures from intestinal contents triatomines were detected through molecular diagnoses of blood samples, and phylogenetic relationship analysis of the isolates parasites using the trypanosome barcode (V7V8 SSUrDNA) were realized. RESULTS Only two Galea spixii (8.1%) and six Triatoma brasiliensis (17.6%) were positive by hemoculture, and the isolates parasites were cryopreserved. All the isolates obtained were positioned on the Trypanosoma cruzi DTU TcI branch. CONCLUSIONS Research focused on studying the wild animal fauna in preserved and underexplored environments has made it possible to elucidate indispensable components of different epidemiological chains of diseases with zoonotic potential.


Subject(s)
Animals , Rodentia/parasitology , Trypanosoma cruzi/genetics , Disease Reservoirs/parasitology , Triatominae/parasitology , Animals, Wild/parasitology , Marsupialia/parasitology , Phylogeny , Rodentia/classification , Trypanosoma cruzi/isolation & purification , Brazil , Biodiversity , Parks, Recreational , Genotype , Marsupialia/classification
9.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 16(1): 78-83, abr. 2018. tab, ilus
Article in Spanish | LILACS, BDNPAR | ID: biblio-997771

ABSTRACT

En el presente estudio evaluamos indicadores entomológicos (índices de infección, colonización e infección natural) de ejemplares de Triatoma sordida capturados en el intra y peridomicilio de viviendas del Chaco Paraguayo en el período 2014 al 2016. El objetivo fue comparar con los hallazgos previamente reportados en el periodo 2010 al 2013 en la misma región. Además se ha incorporado la detección de fuente de alimentación como complemento para definir el riesgo de domiciliación de este vector secundario. Se aplicaron técnicas moleculares asociados a indicadores entomológicos y epidemiológicos a 220 ejemplares de T. sordida capturados en 67 viviendas de 24 localidades del Chaco. Se detectó infestación y colonización por T. sordida en el intradomicilio 13/67 (19%) y 5/13 (38%) y en el peridomicilio 54/67 (81%) y 43/54 (80%), respectivamente. Se detectó infección con T. cruzi en un 17,3% de los ejemplares analizados. La fuente de alimentación pudo detectarse en tan solo 13 de 220 ejemplares (6%), todos resultaron positivos para sangre de gallina y correspondían a captura en el peridomicilio. El índice de infestación intradomiciliar fue del 19%, superior al de años anteriores y similar a las zonas históricamente endémicas de la Región Occidental (18%-20%). El riesgo de transmisión intradomiciliar sigue siendo elevado porque en 3 de 5 viviendas con ninfas de T. sordida, los ejemplares estaban infectados con T. cruzi. Los indicadores entomológicos obtenidos en el presente estudio concuerdan con resultados previos de nuestro equipo, y confirman la capacidad vectorial de este triatomino secundario en la transmisión de la enfermedad de Chagas(AU)


Subject(s)
Animals , Triatoma , Trypanosoma cruzi , Diet , Insect Vectors , Paraguay , Triatoma/genetics , Trypanosoma cruzi/genetics , Chickens/blood , Gene Amplification , Risk Factors , Chagas Disease/transmission , Nucleic Acid Amplification Techniques
10.
Mem. Inst. Oswaldo Cruz ; 113(1): 30-37, Jan. 2018. tab, graf
Article in English | LILACS | ID: biblio-894886

ABSTRACT

BACKGROUND The northern limits of Trypanosoma cruzi across the territory of the United States remain unknown. The known vectors Triatoma sanguisuga and T. lecticularia find their northernmost limits in Illinois; yet, earlier screenings of those insects did not reveal the presence of the pathogen, which has not been reported in vectors or reservoir hosts in this state. OBJECTIVES Five species of medium-sized mammals were screened for the presence of T. cruzi. METHODS Genomic DNA was isolated from heart, spleen and skeletal muscle of bobcats (Lynx rufus, n = 60), raccoons (Procyon lotor, n = 37), nine-banded armadillos (Dasypus novemcinctus, n = 5), Virginia opossums (Didelphis virginiana, n = 3), and a red fox (Vulpes vulpes). Infections were detected targeting DNA from the kinetoplast DNA minicircle (kDNA) and satellite DNA (satDNA). The discrete typing unit (DTU) was determined by amplifying two gene regions: the Spliced Leader Intergenic Region (SL), via a multiplex polymerase chain reaction, and the 24Sα ribosomal DNA via a heminested reaction. Resulting sequences were used to calculate their genetic distance against reference DTUs. FINDINGS 18.9% of raccoons were positive for strain TcIV; the rest of mammals tested negative. MAIN CONCLUSIONS These results confirm for the first time the presence of T. cruzi in wildlife from Illinois, suggesting that a sylvatic life cycle is likely to occur in the region. The analyses of sequences of SL suggest that amplicons resulting from a commonly used multiplex reaction may yield non-homologous fragments.


Subject(s)
Animals , Trypanosoma cruzi/genetics , Chagas Disease/diagnosis , Chagas Disease/veterinary , Armadillos/parasitology , Lynx , Foxes
11.
Mem. Inst. Oswaldo Cruz ; 113(9): e180162, 2018. graf
Article in English | LILACS | ID: biblio-1040603

ABSTRACT

Eukaryotic initiation factor 5A (eIF5A) is a conserved protein with an essential role in translation elongation. Using one and two-dimensional western blotting, we showed that the eIF5A protein level was 2-fold lower in benznidazole (BZ)-resistant (BZR and 17LER) Trypanosoma cruzi populations than in their respective susceptible counterparts (BZS and 17WTS). To confirm the role of eIF5A in BZ resistance, we transfected BZS and 17WTS with the wild-type eIF5A or mutant eIF5A-S2A (in which serine 2 was replaced by alanine). Upon overexpressing eIF5A, both susceptible lines became approximately 3- and 5-fold more sensitive to BZ. In contrast, the eIF5A-S2A mutant did not alter its susceptibility to BZ. These data suggest that BZ resistance might arise from either decreasing the translation of proteins that require eIF5A, or as a consequence of differential levels of precursors for the hypusination reactions (e.g., spermidine and trypanothione), both of which alter BZ's effects in the parasite.


Subject(s)
Humans , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Trypanosoma cruzi/enzymology , Drug Resistance/genetics , Peptide Initiation Factors/metabolism , RNA-Binding Proteins/metabolism , Nitroimidazoles/pharmacology , Trypanosoma cruzi/genetics , Gene Expression , Peptide Initiation Factors/analysis , Peptide Initiation Factors/drug effects , RNA-Binding Proteins/analysis , RNA-Binding Proteins/drug effects
12.
Mem. Inst. Oswaldo Cruz ; 113(8): e180086, 2018. tab, graf
Article in English | LILACS | ID: biblio-1040598

ABSTRACT

Dynamic S-palmitoylation of proteins is the addition of palmitic acid by zDHHC palmitoyl transferases (PATs) and depalmitoylation by palmitoyl protein thioesterases (PPTs). A putative PAT (TcPAT1) has been previously identified in Trypanosoma cruzi, the etiological agent of Chagas disease. Here we analyse other 14 putative TcPATs and 2 PPTs in the parasite genome. T. cruzi cell lines expressing TcPATs and TcPPTs plus a FLAG tag at the C terminus were produced for most enzymes, with positive detection by indirect immunofluorescence. Overexpressed TcPATs were mostly found as single spots at the parasite anterior end, while the TcPPTs were dispersed throughout the parasite body.


Subject(s)
Palmitates/metabolism , Trypanosoma cruzi/metabolism , Protozoan Proteins/metabolism , Protein S/metabolism , Lipoylation/genetics , Trypanosoma cruzi/enzymology , Trypanosoma cruzi/genetics , Protozoan Proteins/genetics , Gene Expression Regulation , Protein S/genetics
13.
Rev. Soc. Bras. Med. Trop ; 50(6): 824-828, Nov.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-1041433

ABSTRACT

Abstract INTRODUCTION: Chagas disease surveillance requires current knowledge on synanthropic triatomines. We analyzed the occurrence and Trypanosoma cruzi infection rates of triatomine bugs in central Brazil, during 2012-2014. METHODS: Triatomines were collected inside or around houses, and T. cruzi infection was determined by optical microscopy and conventional/quantitative polymerase chain reaction. RESULTS: Of the 2706 triatomines collected, Triatoma sordida was the most frequent species in Goiás State, whereas Panstrongylus megistus predominated in the Federal District. Parasites identified were T. cruzi, T. rangeli, and Blastocrithidia sp. CONCLUSIONS: P. megistus and T. sordida sustained the risk of T. cruzi transmission to humans in central Brazil.


Subject(s)
Animals , Male , Female , Triatominae/parasitology , Insect Vectors/parasitology , Trypanosoma cruzi/isolation & purification , Trypanosoma cruzi/genetics , Brazil , Polymerase Chain Reaction , Triatominae/classification , Population Density , Insect Vectors/classification
14.
Rev. Soc. Bras. Med. Trop ; 50(5): 629-637, Sept.-Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-897012

ABSTRACT

Abstract INTRODUCTION: Trypanosoma cruzi, the etiologic agent of Chagas disease, is widely distributed in nature, circulating between triatomine bugs and sylvatic mammals, and has large genetic diversity. Both the vector species and the genetic lineages of T. cruzi present a varied geographical distribution. This study aimed to verify the influence of sympatry in the interaction of T. cruzi with triatomines. Methods: The behavior of the strains PR2256 (T. cruzi II) and AM14 (T. cruzi IV) was studied in Triatoma sordida (TS) and Rhodnius robustus (RR). Eleven fifth-stage nymphs were fed by artificial xenodiagnosis with 5.6 × 103 blood trypomastigotes/0.1mL of each T. cruzi strain. Every 20 days, their excreta were examined for up to 100 days, and every 30 days, the intestinal content was examined for up to 120 days, by parasitological (fresh examination and differential count with Giemsa-stained smears) and molecular (PCR) methods. Rates of infectivity, metacyclogenesis and mortality, and mean number of parasites per insect and of excreted parasites were determined. RESULTS: Sympatric groups RR+AM14 and TS+PR2256 showed higher values of the four parameters, except for mortality rate, which was higher (27.3%) in the TS+AM14 group. General infectivity was 72.7%, which was mainly proven by PCR, showing the following decreasing order: RR+AM14 (100%), TS+PR2256 (81.8%), RR+PR2256 (72.7%) and TS+AM14 (36.4%). CONCLUSIONS: Our working hypothesis was confirmed once higher infectivity and vector capacity (flagellate production and elimination of infective metacyclic forms) were recorded in the groups that contained sympatric T. cruzi lineages and triatomine species.


Subject(s)
Humans , Animals , Arthropod Vectors/physiology , Rhodnius/physiology , Triatoma/physiology , Trypanosoma cruzi/physiology , Sympatry , Arthropod Vectors/genetics , Arthropod Vectors/pathogenicity , Rhodnius/genetics , Rhodnius/pathogenicity , Species Specificity , Time Factors , Triatoma/genetics , Triatoma/pathogenicity , Trypanosoma cruzi/genetics , Trypanosoma cruzi/pathogenicity , Blood/parasitology , Brazil , Polymerase Chain Reaction , Chagas Disease/parasitology , Chagas Disease/transmission , Xenodiagnosis/methods , Host-Parasite Interactions/physiology , Intestines/parasitology , Mice
15.
Rev. Soc. Bras. Med. Trop ; 50(4): 506-515, July-Aug. 2017. tab, graf
Article in English | LILACS | ID: biblio-896996

ABSTRACT

Abstract INTRODUCTION In order to detect Trypanosoma cruzi and determine the genetic profiles of the parasite during the chronic phase of Chagas disease (ChD), parasitological and molecular diagnostic methods were used to assess the blood of 91 patients without specific prior treatment. METHODS Blood samples were collected from 68 patients with cardiac ChD and 23 patients with an indeterminate form of ChD, followed by evaluation using blood culture and polymerase chain reaction. T . cruzi isolates were genotyped using three different genetic markers. RESULTS: Blood culture was positive in 54.9% of all patients, among which 60.3% had the cardiac form of ChD, and 39.1% the indeterminate form of ChD. There were no significant differences in blood culture positivity among patients with cardiac and indeterminate forms. Additionally, patient age and clinical forms did not influence blood culture results. Polymerase chain reaction (PCR) was positive in 98.9% of patients, although comparisons between blood culture and PCR results showed that the two techniques did not agree. Forty-two T . cruzi stocks were isolated, and TcII was detected in 95.2% of isolates. Additionally, one isolate corresponded to TcIII or TcIV, and another corresponded to TcV or TcVI. CONCLUSIONS Blood culture and PCR were both effective for identifying T. cruzi using a single blood sample, and their association did not improve parasite detection. However, we were not able to establish an association between the clinical form of ChD and the genetic profile of the parasite.


Subject(s)
Humans , Male , Female , Adult , Aged , Trypanosoma cruzi/isolation & purification , Trypanosoma cruzi/genetics , DNA, Protozoan/genetics , Chagas Disease/diagnosis , Polymerase Chain Reaction , Chronic Disease , Sensitivity and Specificity , Chagas Disease/blood , Blood Culture , Genotype , Middle Aged
16.
Mem. Inst. Oswaldo Cruz ; 112(6): 437-446, June 2017. tab, graf
Article in English | LILACS | ID: biblio-841807

ABSTRACT

BACKGROUND The Trypanosoma cruzi infection endemic in Latin America has now spread to several countries across four continents; this endemic involves triatomine vector-free protists. We hypothesised that the sexual transmission of T. cruzi contributes to the ongoing spread of Chagas disease. OBJECTIVES A short-term longitudinal study was conducted to evaluate this hypothesis. METHODS The study population comprised 109 subjects from four families, among whom 21 had been diagnosed with acute Chagas disease by direct parasitological analysis. Blood mononuclear cells and serum samples were obtained from each study subject once per year for three consecutive years. Enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence serological examinations were used to detect specific T. cruzi antibodies. Polymerase chain reaction of T. cruzi DNA revealed 188-nucleotide bands, which hybridised to a specific radiolabelled probe and were confirmed by cloning and sequencing. RESULTS Three independent assessments at different time points revealed T. cruzi nuclear DNA footprints in 76% (83/109) of the study population with active infection. In contrast, the ELISA and indirect immunofluorescence assays detected the T. cruzi antibody in 28.4% (31/109) of the study samples. Moreover, the semen from 82.6% (19/23) of subjects people revealed harboured the 188- bp base pair T. cruzi footprint. Interestingly, the ejaculates of nuclear DNA-positive Chagas patient transmitted the T. cruzi upon peritoneal injection or infusion in the vagina of mice, and amastigotes were detected in the skeletal muscle, myocardium, vas deferens, and uterine tube. MAIN CONCLUSIONS T. cruzi infections can be transmitted from females or males to naïve mates through intercourse, and progeny showed discrepancies between the ratios of nuclear DNA footprints and specific antibody that can be explained by the tolerance attained during early embryo growth. Additional studies are needed to develop drugs to eradicate the infections. Additionally, the importance of a vigorous education, information, and communication program to prevent sexually transmitted Chagas disease in humans cannot be underemphasised.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Trypanosoma cruzi/genetics , Trypanosoma cruzi/immunology , Sexually Transmitted Diseases/epidemiology , Chagas Disease/transmission , Chagas Disease/epidemiology , Enzyme-Linked Immunospot Assay , Brazil/epidemiology , Polymerase Chain Reaction , Longitudinal Studies , Fluorescent Antibody Technique
17.
Mem. Inst. Oswaldo Cruz ; 112(3): 224-235, Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-841775

ABSTRACT

Chagas cardiomyopathy is the most frequent and most severe manifestation of chronic Chagas disease, and is one of the leading causes of morbidity and death in Latin America. Although the pathogenesis of Chagas cardiomyopathy is incompletely understood, it may involve several mechanisms, including parasite-dependent myocardial damage, immune-mediated myocardial injury (induced by the parasite itself and by self-antigens), and microvascular and neurogenic disturbances. In the past three decades, a consensus has emerged that parasite persistence is crucial to the development and progression of Chagas cardiomyopathy. In this context, antiparasitic treatment in the chronic phase of Chagas disease could prevent complications related to the disease. However, according to the results of the BENEFIT trial, benznidazole seems to have no benefit for arresting disease progression in patients with chronic Chagas cardiomyopathy. In this review, we give an update on the main pathogenic mechanisms of Chagas disease, and re-examine and discuss the results of the BENEFIT trial, together with its limitations and implications.


Subject(s)
Humans , Animals , Male , Female , Middle Aged , Trypanocidal Agents/therapeutic use , Trypanosoma cruzi/drug effects , Trypanosoma cruzi/genetics , Chagas Cardiomyopathy/etiology , Chagas Cardiomyopathy/parasitology , Chagas Cardiomyopathy/drug therapy , Nitroimidazoles/therapeutic use , Chronic Disease , Clinical Trials as Topic , Treatment Outcome , Disease Progression
18.
Rev. chil. infectol ; 34(1): 69-76, feb. 2017. ilus, graf
Article in Spanish | LILACS | ID: biblio-844448

ABSTRACT

Although infrequent, Trypanosoma cruzi reactivation is possible among patients with HIV/AIDS infection that develop a tumor-like or granulomatous lesion in the CNS. We report the case of a 60 years old male patient with HIV/AIDS and low CD4 lymphocytes count with cerebellar symptoms and mild paresis, associated to supra and infratentorial hypodense lesions and positive serology tests both to T. gondii and Trypanosoma cruzi. Empirical therapy against toxoplasmosis was prescribed together with antiretroviral therapy but without a favorable response. Brain Chagas disease was confirmed by quantitative PCR in the CSF but he died despite nifurtimox treatment. Despite its rare occurrence, Chagas disease affecting the CNS is possible among patients with HIV/AIDS infection. Epidemiological exposure, a positive Chagas serological test and the image pattern of brain lesions support the suspicion. Diagnosis can be confirmed by molecular test in CSF samples, including new quantitative methods. Despite an adverse prognosis, specific therapy can be attempted besides antiretroviral treatment.


La reactivación de la infección por Trypanosoma cruzi es un diagnóstico infrecuente pero posible en pacientes con infección por VIH/SIDA y una lesión de tipo tumoral o granulomatosa en el sistema nervioso central. Presentamos el caso clínico de un paciente de 60 años con VIH/SIDA y recuentos bajos de linfocitos CD4, con síntomas cerebelosos y paresia leve, lesiones hipodensas supra e infratentoriales y serología positiva para Toxoplasma gondii y T. cruzi. Se trató empíricamente como una toxoplasmosis cerebral y con terapia antiretroviral, sin respuesta clínica. La enfermedad de Chagas cerebral se confirmó por RPC cuantitativa en el LCR. El paciente falleció a pesar de recibir terapia con nifurtimox. Apoyan la posibilidad de un Chagas cerebral en pacientes con VIH/SIDA, la exposición epidemiológica, la serología positiva y el patrón de distribución de las lesiones en las imágenes. El diagnóstico puede mejorarse con técnicas moleculares cuantitativas en LCR. A pesar de su mal pronóstico, se puede intentar una terapia específica junto al tratamiento antiretroviral.


Subject(s)
Humans , Male , Middle Aged , Trypanosoma cruzi/genetics , Chagas Disease/diagnosis , AIDS-Related Opportunistic Infections/diagnosis , Central Nervous System Protozoal Infections/diagnosis , Trypanosoma cruzi/isolation & purification , Magnetic Resonance Imaging , Cerebrospinal Fluid/parasitology , Polymerase Chain Reaction , AIDS-Related Opportunistic Infections/parasitology , Fatal Outcome , CD4 Lymphocyte Count , Viral Load , Central Nervous System Protozoal Infections/parasitology , Diagnosis, Differential
19.
Rev. Soc. Bras. Med. Trop ; 50(1): 35-43, Jan.-Feb. 2017. tab, graf
Article in English | LILACS | ID: biblio-842817

ABSTRACT

ABSTRACT INTRODUCTION: Trypanosoma cruzi is the etiologic agent of Chagas disease in humans, mainly in Latin America. Trypanosome stocks were isolated by hemoculture from patients followed at Evandro Chagas National Institute of Infectious Diseases (FIOCRUZ) and studied using different approaches. METHODS: For species and genotype identification, the stocks were analyzed by parasitological techniques, polymerase chain reaction assays targeted to specific DNA sequences, isoenzyme patterns, besides sequencing of a polymorphic locus of TcSC5D gene (one stock). RESULTS: The isolates presented typical T. cruzi morphology and usually grew well in routine culture media. Metacyclic trypomastigotes were found in cultures or experimentally infected Triatoma infestans. All isolates were pure T. cruzi cultures, presenting typical 330-bp products from kinetoplast DNA minicircles, and 250 or 200-bp amplicons from the mini-exon non-transcribed spacer. Their genetic type assignment was resolved by their isoenzyme profiles. The finding of TcI in one asymptomatic patient from Paraíba was confirmed by the sequencing assay. TcVI was found in two asymptomatic individuals from Bahia and Rio Grande do Sul. TcII was identified in six patients from Pernambuco, Bahia and Minas Gerais, who presented different clinical forms: cardiac (2), digestive with megaesophagus (1), and indeterminate (3). CONCLUSIONS: The main T. cruzi genotypes found in Brazilian chronic patients were identified in this work, including TcI, which is less frequent and usually causes asymptomatic disease, unlike that in other American countries. This study emphasizes the importance of T. cruzi genotyping for possible correlations between the parasite and patient’ responses to therapeutic treatment or disease clinical manifestations.


Subject(s)
Humans , Male , Female , Adult , Aged , Trypanosoma cruzi/genetics , DNA, Protozoan , Chagas Disease/parasitology , Phylogeny , Brazil , Polymerase Chain Reaction , Chronic Disease , Genotype , Middle Aged
20.
Belo Horizonte; s.n; 2017. 152 p.
Thesis in Portuguese | LILACS, ColecionaSUS | ID: biblio-943111

ABSTRACT

Paradoxalmente vivemos um momento da pesquisa científica em que possuímos um volume abundante de dados, mas com dificuldades cada vez maiores de se obter informações a partir deles. Diversidade de formatos, dificuldade na construção de uma forma de acesso simples, mas não superficial, ausência de um identificador único para as unidades biológicas de estudo (proteínas, RNAs, genes, etc.) e falta de integração entre os bancos de dados são alguns dos desafios enfrentados cotidianamente na tarefa de mineração de informações a partir dessas diversas fontes. Com o objetivo de contribuir na tarefa de extração de informações a partir de fontes públicas, mediante a integração de dados de enriquecimento funcional, construímos uma metodologia de trabalho que permite a obtenção, filtragem e tratamento de dados oriundos do banco STRING v.10 e de análises massivas de RNA e proteínas, integrando-os em redes de interação proteína-proteína através do software Cytoscape. Como organismo modelo, trabalhamos com dois clones de Trypanosoma cruzi, apresentando diferenças relacionadas aos perfis de infectividade (alta e baixa infectividade). Utilizamos dados de genes diferencialmente expressos identificados em experimentos de RNA-Seq e shotgun proteomics . Durante o estudo foram construídos 11 scripts e 3 programas, parte integrante de uma metodologiamodular aplicável a outros organismos e modelos experimentais, tanto em sua totalidade quando parcialmente


Como resultado, além da metodologia, obtivemos também o resultado de sua implementação, que consistiu de uma série de redes deinteração proteína-proteína do organismo estudado, onde foram destacadas características de interesse biológico, tais como informações de EC number, agrupamentos funcionais, tipo de interação entre as proteínas e importância dasproteínas segundo métricas de teoria de grafos. Concluímos, então, que a utilização de redes de interação proteína-proteína pode ser uma ótima estratégia tanto para a realização de novos estudos quanto para a revisão de estudos anteriores, uma vez que podemos extrair novas informações a partir de dados já existentes publicamente. Além disso as redes nos fornecem uma visão sistêmica do organismo, o que pode desvelar novos olhares sobre a sua biologia dos organismos de estudo


Subject(s)
Chagas Disease/genetics , Computational Biology/instrumentation , Trypanosoma cruzi/genetics
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