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1.
Mem Inst Oswaldo Cruz ; 113(1): 3-8, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29211102

RESUMO

BACKGROUND: Trypanosoma cruzi circulates in sylvatic habitats, mainly through blood-feeding triatomines, although other routes also contribute to its dispersion. Sexual transmission of T. cruzi is an understudied topic, especially among wild mammals. Because of the difficulties inherent to field work, experimentally infected mice are frequently used to evaluate the transmission of T. cruzi. OBJECTIVE: This study aimed to evaluate the sexual transmission of T. cruzi in acutely infected mice. METHODS: Male and female mice in the acute phase of Chagas disease were mated with naïve partners. Then, parasitological tests, immunohistochemistry, serological assays, and polymerase chain reaction (PCR) assays were used to detect infection. FINDINGS: Parasitological analysis showed trypomastigotes in the blood of 20% of the naïve mice after mating with infected partners. Serological assays detected anti-T. cruzi antibodies in all naïve females mated with infected males and in 60% of naïve males mated with infected females. PCR showed T. cruzi nDNA bands for all naïve mice mated with infected partners. The possibility of sexual transmission was also confirmed by visualisation of amastigotes in the testes. MAIN CONCLUSIONS: Our results demonstrate that sexual transmission of T. cruzi is an ordinary event that may contribute to maintenance of the parasite's enzootic cycle.


Assuntos
Doença de Chagas/transmissão , Trypanosoma cruzi/fisiologia , Animais , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/sangue , Modelos Animais de Doenças , Feminino , Masculino , Camundongos Endogâmicos BALB C , Infecções Sexualmente Transmissíveis/parasitologia , Infecções Sexualmente Transmissíveis/transmissão , Trypanosoma cruzi/imunologia
2.
Mem Inst Oswaldo Cruz ; 112(6): 437-446, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28591404

RESUMO

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.


Assuntos
Doença de Chagas/transmissão , Infecções Sexualmente Transmissíveis/parasitologia , Trypanosoma cruzi , Doença Aguda , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Criança , Pré-Escolar , ELISPOT , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/transmissão , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia , Adulto Jovem
3.
Exp Parasitol ; 162: 1-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26724377

RESUMO

Trypanosoma cruzi is mainly transmitted by blood-sucking triatomines, but other routes also have epidemiological importance, such as blood transfusion and congenital transmission. Although the possibility of sexual transmission of T. cruzi has been suggested since its discovery, few studies have been published on this subject. We investigated acquisition of T. cruzi by sexual intercourse in an experimental murine model. Male and female mice in the chronic phase of Chagas disease were mated with naive partners. Parasitological, serological and molecular tests demonstrated the parasites in tissues and blood of partners. These results confirm the sexual transmission of T. cruzi in mice.


Assuntos
Doença de Chagas/transmissão , Infecções Sexualmente Transmissíveis/transmissão , Trypanosoma cruzi/fisiologia , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Doença de Chagas/parasitologia , Doença de Chagas/patologia , DNA de Protozoário/análise , DNA de Protozoário/sangue , DNA de Protozoário/isolamento & purificação , Modelos Animais de Doenças , Feminino , Gônadas/parasitologia , Coração/parasitologia , Intestinos/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Músculo Esquelético/parasitologia , Carga Parasitária , Infecções Sexualmente Transmissíveis/parasitologia , Infecções Sexualmente Transmissíveis/patologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia
4.
Acta Trop ; 247: 107018, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37673134

RESUMO

The neglected parasitosis giardiasis is one of the most common intestinal infections worldwide, affecting mainly infants and young children. Giardia duodenalis may disturb the local microbiome, leading to intestinal ecosystem disorders, and altering different processes in the host, such as the immune response. Nevertheless, the alterations promoted by G. duodenalis on the human gut microbiome have not been thoroughly investigated. Here, we characterized the gut microbiota of G. duodenalis-infected children and determine the main alterations promoted by the parasite. To do so, fecal samples of 26 infected and four uninfected children aged 2 to 6 years old were processed for High Efficiency Microarray analysis, in order to describe their bacterial and viral profiles. Then, we quantified the total bacterial population by qPCR and assessed fecal calprotectin levels, which are closely related with gut inflammation. A total of 286 bacteria's species and 17 viruses' strains were identified. Our results revealed no statistically significant differences between G. duodenalis positive and negative groups in the taxa's phyla and families. However, bacterial species diversity was increased in children infected with G. duodenalis (p < 0.05), while the total number of bacteria was decreased (p < 0.05). Considering the virome analysis, 17 different strains were identified, 88% being bacteriophages. The correlation analysis revealed an important disruption in the balance of DNA virus and bacteria within the intestinal microbiota of Giardia-positive children. Our findings constitute the first description of the gut virome of Giardia-infected children and suggest that G. duodenalis infection exerts a modulatory effect on the gut microbiome, promoting local inflammation and altering the equilibrium of the parasite-microbiota-host triad. This highlights the importance of considering polymicrobial associations and understanding the broader context of giardiasis. Overall, our study provides new insights into the complex interactions between intestinal parasites and the microbiota, which may have implications for the development of novel therapeutic interventions in the future.


Assuntos
Microbioma Gastrointestinal , Gastrópodes , Giardia lamblia , Giardíase , Microbiota , Lactente , Animais , Humanos , Criança , Pré-Escolar , Vírus de DNA , Giardia , Bactérias/genética , Inflamação
5.
Artigo em Inglês | MEDLINE | ID: mdl-35772309

RESUMO

In addition to the long-established role in erythropoiesis, erythropoietin (Epo) has protective functions in a variety of tissues, including the heart. This is the most affected organ in chronic Chagas disease, caused by the protozoan Trypanosoma cruzi. Despite seven million people being infected with T. cruzi worldwide, there is no effective treatment preventing the disease progression to the chronic phase when the pathological involvement of the heart is often observed. Chronic chagasic cardiomyopathy has a wide variety of manifestations, like left ventricular systolic dysfunction, dilated cardiomyopathy, and heart failure. Since Epo may help maintain cardiac function by reducing myocardial necrosis, inflammation, and fibrosis, this study aimed to evaluate whether the Epo has positive effects on experimental Chagas disease. For that, we assessed the earlier (acute phase) and also the later (chronic phase) use of Epo in infected C57BL/6 mice. Blood cell count, biochemical parameters, parasitic load, and echocardiography data were evaluated. In addition, histopathological analysis was carried out. Our data showed that Epo had no trypanocide effect nor did it modify the production of anti-T. cruzi antibodies. Epo-treated groups exhibited parasitic burden much lower in the heart compared to blood. No pattern of hematological changes was observed combining infection with treatment with Epo. Chronic Epo administration reduced CK-MB serum activity from d0 to d180, irrespectively of T. cruzi infection. Likewise, echocardiography and histological results indicate that Epo treatment is more effective in the chronic phase of experimental Chagas disease. Since treatment is one of the greatest challenges of Chagas disease, alternative therapies should be investigated, including Epo combined with benznidazole.


Assuntos
Fármacos Cardiovasculares , Cardiomiopatia Chagásica , Eritropoetina , Animais , Fármacos Cardiovasculares/uso terapêutico , Cardiomiopatia Chagásica/tratamento farmacológico , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Modelos Animais de Doenças , Eritropoetina/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Carga Parasitária , Trypanosoma cruzi
6.
PLoS Negl Trop Dis ; 16(12): e0011011, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36525465

RESUMO

BACKGROUND: Domestic dogs are primary reservoir hosts of Leishmania infantum, the agent of visceral leishmaniasis. Detecting dog infections is central to epidemiological inference, disease prevention, and veterinary practice. Error-free diagnostic procedures, however, are lacking, and the performance of those available is difficult to measure in the absence of fail-safe "reference standards". Here, we illustrate how a hierarchical-modeling approach can be used to formally account for false-negative and false-positive results when investigating the process of Leishmania detection in dogs. METHODS/FINDINGS: We studied 294 field-sampled dogs of unknown infection status from a Leishmania-endemic region. We ran 350 parasitological tests (bone-marrow microscopy and culture) and 1,016 qPCR assays (blood, bone-marrow, and eye-swab samples with amplifiable DNA). Using replicate test results and site-occupancy models, we estimated (a) clinical sensitivity for each diagnostic procedure and (b) clinical specificity for qPCRs; parasitological tests were assumed 100% specific. Initial modeling revealed qPCR specificity < 94%; we tracked the source of this unexpected result to some qPCR plates having subtle signs of possible contamination. Using multi-model inference, we formally accounted for suspected plate contamination and estimated qPCR sensitivity at 49-53% across sample types and dog clinical conditions; qPCR specificity was high (95-96%), but fell to 81-82% for assays run in plates with suspected contamination. The sensitivity of parasitological procedures was low (~12-13%), but increased to ~33% (with substantial uncertainty) for bone-marrow culture in seriously-diseased dogs. Leishmania-infection frequency estimates (~49-50% across clinical conditions) were lower than observed (~60%). CONCLUSIONS: We provide statistical estimates of key performance parameters for five diagnostic procedures used to detect Leishmania in dogs. Low clinical sensitivies likely reflect the absence of Leishmania parasites/DNA in perhaps ~50-70% of samples drawn from infected dogs. Although qPCR performance was similar across sample types, non-invasive eye-swabs were overall less likely to contain amplifiable DNA. Finally, modeling was instrumental to discovering (and formally accounting for) possible qPCR-plate contamination; even with stringent negative/blank-control scoring, ~4-5% of positive qPCRs were most likely false-positives. This work shows, in sum, how hierarchical site-occupancy models can sharpen our understanding of the problem of diagnosing host infections with hard-to-detect pathogens including Leishmania.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Leishmaniose , Cães , Animais , Doenças do Cão/diagnóstico , Sensibilidade e Especificidade , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Leishmania infantum/genética , Leishmaniose/diagnóstico , Leishmaniose/veterinária
7.
Front Cell Infect Microbiol ; 12: 956112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36017367

RESUMO

Tegumentary leishmaniasis is a tropical disease caused by protozoa of the genus Leishmania. Clinically, the disease presents a broad spectrum of symptoms, the mechanisms underlying the development of lesions remaining to be fully elucidated. In the present work, we performed a correlation and multiparametric analysis to evaluate how parasite- and host-related aspects associate with each other, and with the different clinical manifestations of tegumentary leishmaniasis. This cross-sectional study involved 75 individuals from endemic areas of Brazil, grouped according to their symptoms. Leishmania species were determined by DNA sequencing, and parasite load, antibody production, and cytokine profile were evaluated by kDNA qPCR, ELISA, and flow cytometry. Data were analyzed using the Chi-square test, principal component analysis, canonical discriminant analysis, and correlation analysis. Among the recruited patients, 23 (31%) were asymptomatic, 34 (45%) had primary cutaneous leishmaniasis, 10 (13%) presented recurrent cutaneous leishmaniasis, and eight (11%) had mucocutaneous leishmaniasis. Leishmania species identified included L. amazonensis, L. braziliensis, and L. guyanensis. Surprisingly, no Leishmania RNA virus infection was detected in any sample. In summary, our work showed that parasite load, antibody production, and cytokine levels alone are not determinants for tegumentary leishmaniasis symptoms. However, the correlation analysis allowed us to observe how these factors are correlated to each other within the groups, which revealed a unique network for each clinical manifestation. Our work reinforces the complexity of tegumentary leishmaniasis outcomes - which are associated with multiple host and parasite-related elements and provides a holistic model of the disease.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Parasitos , Animais , Estudos Transversais , Citocinas , Humanos , Leishmania/genética , Leishmania braziliensis/genética , Leishmaniose Cutânea/patologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-33533811

RESUMO

Chagas disease (CD) is caused by the protozoan Trypanosoma cruzi and it is mainly acquired through the vector route, however, blood transfusion and congenital transmission are implicated in the spread of the illness worldwide. The congenital route can occur at any stage of pregnancy and its frequency varies. In the Federal District, in Brazil, the frequency of T. cruzi infection in pregnant women and their offspring has not been updated. Thus, the aim of this study was to estimate the prevalence of T. cruzi infection in pregnant women and the rate of congenital transmission in the Federal District. A cross-sectional study was conducted to estimate the seroprevalence of T. cruzi from 2014 to 2016 in the population of pregnant women attended by the public health service throughout the Federal District and a descriptive cohort for the evaluation of congenital transmission. During the study, prenatal data of 98,895 women were consulted and pregnant women registered in 2016, presenting with positive T. cruzi serology, were part of the descriptive cohort. The estimated prevalence of T. cruzi infection in the three years was 0.19% and the congenital transmission rate was 1/40 (2.5%). Our results have shown that, although the main routes of transmission of CD have been interrupted, there is still a risk of congenital transmission in the Federal District. This present study highlights the need for the continuous implementation of a screening program for pregnant women and timely treatment of infected newborns and children.


Assuntos
Doença de Chagas/epidemiologia , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Complicações Parasitárias na Gravidez/epidemiologia , Trypanosoma cruzi/isolamento & purificação , Brasil/epidemiologia , Doença de Chagas/diagnóstico , Doença de Chagas/transmissão , Criança , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Gravidez , Gestantes , Cuidado Pré-Natal , Prevalência , Estudos Soroepidemiológicos
9.
Acta Trop ; 224: 106127, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34509459

RESUMO

The conservation of genomic integrity and stability is essential for cell survival. DNA Damage Responses (DDRs) are considered of paramount importance for all living beings and involve mechanisms of cell cycle regulation and damage-specific DNA repair pathways. Hydrogen peroxide (H2O2) is a compound that, in supraphysiological concentrations, damages biomolecules including the DNA, causing base modifications and strand breaks. There is evidence that Trypanosoma cruzi, the protozoan that causes Chagas disease, interferes in the host cell's DNA metabolism. In order to investigate the influence of T. cruzi infection over the host cell capacity to withstand and repair DNA damage, we analyzed L6 cells infected with Berenice, and Colombiana T. cruzi strains according to their viability, proliferation, morphology, DNA degradation, expression of DNA repair, and cell cycle genes following H2O2 treatment. It was noted that T. cruzi infection might act as either a stressor or a protective element of host DNA, depending on the strain and H2O2 concentration. Cells infected with Berenice strain and treated with 0.8 mM H2O2 presented a reduced DNA damage response intensity (e.g., BER and HR). Infection with T. cruzi Colombiana prevented the activation of DNA repair pathways in response to 0.8mM and 1.6mM H2O2 (NER and MMR). Nevertheless, since cellular viability was not significantly compromised in Colombiana-infected cells following the oxidative insult, it is possible that the parasite directly influenced the host DNA repair machinery. Our results support the notion that T. cruzi is able to modulate the host cell DNA metabolism in a strain-dependent manner, an event which can be explored in future drug development strategies.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Doença de Chagas/tratamento farmacológico , Dano ao DNA , Reparo do DNA , Humanos , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo
10.
Acta Trop ; 214: 105782, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33259817

RESUMO

Originated in Wuhan, China, the coronavirus 19 disease (COVID-19) has quickly spread worldwide, reaching countries that already faced other endemics and epidemics. In Brazil, such a concerning situation includes arboviruses, among which the dengue virus stands out. Here, we determined the rate of SARS-CoV-2/dengue virus co-infection in a total of 178 patients with COVID-19 symtoms admitted into a large public hospital of the Federal District of Brazil. Furthermore, we evaluated whether prior or active dengue virus infection influenced hematological, biochemical, and clinical parameters of such patients. One hundred and twelve (63%) individuals tested positive for COVID-19, of which 43 (38.4%) were co-infected with dengue virus, and 50 (44.6%) had antibodies indicative of previous dengue infection. Co-infected patients showed lower numbers of circulating lymphocytes and monocytes, higher glucose rates, and a worse pulmonary condition. Of note, prior infections with dengue virus did not influence clinical parameters, but active dengue fever resulted in higher hospitalization rate. In conclusion, amid the current complex epidemiological scenario in Brazil, our data support the notion that SARS-CoV-2 and dengue co-infection affects an important percentage of COVID-19 patients and leads to worse clinical parameters, requiring greater attention from health authorities.


Assuntos
COVID-19/sangue , COVID-19/diagnóstico , Coinfecção/sangue , Dengue/sangue , Dengue/diagnóstico , Adulto , Alanina Transaminase/sangue , Anticorpos Antivirais/sangue , Aspartato Aminotransferases/sangue , Glicemia/análise , Brasil , Coinfecção/diagnóstico , Creatina Quinase/sangue , Dengue/imunologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Imunoglobulina G/sangue , L-Lactato Desidrogenase/sangue , Contagem de Linfócitos , Masculino , Estudos de Amostragem
11.
Pflugers Arch ; 459(5): 713-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20119684

RESUMO

Erythropoietin (Epo)-induced polycythemia is the main factor of adaptation to hypoxia. In this study, we analysed the effects of Epo deficiency on intrinsic functional properties of slow and fast twitch muscles in a model of erythropoietin deficient mice (Epo-TAg(h)) exposed to hypoxia. We hypothesised that Epo deficiency would be deleterious for skeletal muscle structure and phenotype, which could change its functional properties and alters the adaptive response to ambient hypoxia. Wild-type (WT) and Epo-TAg(h) mice were left in hypobaric chamber at 420 mm Hg pressure for 14 days. Soleus (SOL) and extensor digitorum longus (EDL) were analysed in vitro by mechanical measurements, immunohistological and biochemical analyses. The results were compared to those obtained in corresponding muscles of age-matched normoxic groups. Our data did not show any difference between the groups whatever the Epo deficiency and/or hypoxic conditions for twitch force, tetanic force, fatigue, typology and myosin heavy chain composition. Normoxic Epo-TAg(h) mice exhibit improved capillary-to-fibre ratio compared to WT mice in both SOL and EDL whereas no angiogenic effects of hypoxia or combined Epo-deficiency/hypoxia were observed. These results suggest that skeletal muscles possess a great capacity of adaptation to Epo deficiency. Then Epo deficiency is not a sufficient factor to modify intrinsic functional properties of skeletal muscles.


Assuntos
Eritropoetina/genética , Hipóxia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Animais , Eritropoetina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Fadiga Muscular/fisiologia
12.
J Biomed Biotechnol ; 2010: 137817, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20414335

RESUMO

Erythropoietin (Epo) and vascular growth factor (VEGF) are known to be involved in the regulation of cellular activity when oxygen transport is reduced as in anaemia or hypoxic conditions. Because it has been suggested that Epo could play a role in skeletal muscle development, regeneration, and angiogenesis, we aimed to assess Epo deficiency in both normoxia and hypoxia by using an Epo-deficient transgenic mouse model (Epo-TAg(h)). Histoimmunology, ELISA and real time RT-PCR did not show any muscle fiber atrophy or accumulation of active HIF-1alpha but an improvement of microvessel network and an upregulation of VEGFR2 mRNA in Epo-deficient gastrocnemius compared with Wild-Type one. In hypoxia, both models exhibit an upregulation of VEGF120 and VEGFR2 mRNA but no accumulation of Epo protein. EpoR mRNA is not up-regulated in both Epo-deficient and hypoxic gastrocnemius. These results suggest that muscle deconditioning observed in patients suffering from renal failure is not due to Epo deficiency.


Assuntos
Eritropoetina/fisiologia , Hipóxia/metabolismo , Fibras Musculares Esqueléticas/fisiologia , Análise de Variância , Animais , Eritropoetina/sangue , Eritropoetina/genética , Eritropoetina/metabolismo , Histocitoquímica , Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Microvasos/crescimento & desenvolvimento , Microvasos/metabolismo , Fibras Musculares Esqueléticas/química , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Atrofia Muscular , Neovascularização Fisiológica/fisiologia , Receptores da Eritropoetina/metabolismo , Sarcômeros , Estatísticas não Paramétricas , Regulação para Cima , Fatores de Crescimento do Endotélio Vascular/genética , Fatores de Crescimento do Endotélio Vascular/metabolismo
13.
Expert Rev Mol Diagn ; 19(10): 875-894, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31496309

RESUMO

Introduction: The diagnosis in Chagas disease is a challenge because most infections with Trypanosoma cruzi are asymptomatic and currently serological tests have limitations, such as cross-reactivity with other trypanosomatids. Real-time PCR (qPCR) is a useful procedure that allows T. cruzi detection even when the parasitic load is very low and seems interesting for monitoring the response to trypanocidal treatment and elucidating cases with doubtful serological results. Areas covered: This systematic review aimed to investigate the applications and relevance of qPCR in human Chagas disease, and focus on the methodological aspects. Expert opinion: The results showed that blood samples with the TaqMan procedure direct to nuclear DNA (nDNA) sequences are used the most. However, a high variability among laboratories concerning the qPCR methods make it difficult to compare between studies and the use in routine surveillance laboratories, even if some works had performed an analytical validation of T. cruzi qPCR to try to counteract this. Nevertheless, the detection of T. cruzi by qPCR has multiple advantages including fast results, reduction of carryover contamination compared to conventional PCR, and high sensitivity and specificity. This study has given an overview of assays using qPCR in human Chagas disease and has shown the relevance of this technique in diagnosis.


Assuntos
Doença de Chagas/diagnóstico , Doença de Chagas/parasitologia , Trypanosoma cruzi/genética , DNA de Protozoário/genética , Humanos , Carga Parasitária/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade
14.
Rev Soc Bras Med Trop ; 52: e20180069, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30810649

RESUMO

INTRODUCTION: Chagas disease (CD), a neglected endemic disease in Latin America, has acquired new epidemiological characteristics with an increase in the importance of alternative transmission routes such as congenital transmission. We evaluated the scientific research on this subject. METHODS: We searched the Scielo, BVS, and PubMed databases from 2006 to 2017. RESULTS: We identified a small number of published articles, mostly in journals with an impact factor less than 3.0. Studies on human congenital transmission of CD were carried out in only seven different countries. CONCLUSIONS: Our data highlight the lack of research on congenital CD.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Doença de Chagas/congênito , Publicações Periódicas como Assunto/estatística & dados numéricos , Publicações/estatística & dados numéricos , Bibliometria , Humanos , Fator de Impacto de Revistas
15.
Front Microbiol ; 10: 1856, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496999

RESUMO

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi (T. cruzi), is the main parasitic disease in the Western Hemisphere. Unfortunately, its physiopathology is not completely understood, and cardiomegaly development is hard to predict. Trying to explain tissue lesion and the fact that only a percentage of the infected individuals develops clinical manifestations, a variety of mechanisms have been suggested as the provokers of CD, such as parasite persistence and autoimmune responses. However, holistic analysis of how parasite and host-related elements may connect to each other and influence clinical outcome is still scarce in the literature. Here, we investigated murine models of CD caused by three different pathogen strains: Colombian, CL Brener and Y strains, and employed parasitological and immunological tests to determine parasite load, antibody reactivity, and cytokine production during the acute and chronic phases of the disease. Also, we developed a quantitative PCR (qPCR) protocol to quantify T. cruzi kDNA minicircle integration into the mammalian host genome. Finally, we used a correlation analysis to interconnect parasite- and host-related factors over time. Higher parasite load in the heart and in the intestine was significantly associated with IgG raised against host cardiac proteins. Also, increased heart and bone marrow parasitism was associated with a more intense leukocyte infiltration. kDNA integration rates correlated to the levels of IgG antibodies reactive to host cardiac proteins and interferon production, both influencing tissue inflammation. In conclusion, our results shed light into how inflammatory process associates with parasite load, kDNA transfer to the host, autoreactive autoantibody production and cytokine profile. Altogether, our data support the proposal of an updated integrative theory regarding CD pathophysiology.

16.
Sci Rep ; 8(1): 151, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29317702

RESUMO

Vector-borne pathogens threaten human health worldwide. Despite their critical role in disease prevention, routine surveillance systems often rely on low-complexity pathogen detection tests of uncertain accuracy. In Chagas disease surveillance, optical microscopy (OM) is routinely used for detecting Trypanosoma cruzi in its vectors. Here, we use replicate T. cruzi detection data and hierarchical site-occupancy models to assess the reliability of OM-based T. cruzi surveillance while explicitly accounting for false-negative and false-positive results. We investigated 841 triatomines with OM slides (1194 fresh, 1192 Giemsa-stained) plus conventional (cPCR, 841 assays) and quantitative PCR (qPCR, 1682 assays). Detections were considered unambiguous only when parasitologists unmistakably identified T. cruzi in Giemsa-stained slides. qPCR was >99% sensitive and specific, whereas cPCR was ~100% specific but only ~55% sensitive. In routine surveillance, examination of a single OM slide per vector missed ~50-75% of infections and wrongly scored as infected ~7% of the bugs. qPCR-based and model-based infection frequency estimates were nearly three times higher, on average, than OM-based indices. We conclude that the risk of vector-borne Chagas disease may be substantially higher than routine surveillance data suggest. The hierarchical modelling approach we illustrate can help enhance vector-borne disease surveillance systems when pathogen detection is imperfect.

18.
Rev Soc Bras Med Trop ; 50(6): 824-828, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29340461

RESUMO

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.


Assuntos
Insetos Vetores/parasitologia , Triatominae/parasitologia , Trypanosoma cruzi/isolamento & purificação , Animais , Brasil , Feminino , Insetos Vetores/classificação , Masculino , Reação em Cadeia da Polimerase , Densidade Demográfica , Triatominae/classificação , Trypanosoma cruzi/genética
19.
Parasit Vectors ; 9: 39, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26813657

RESUMO

BACKGROUND: Neotropical primates are important sylvatic hosts of Trypanosoma cruzi, the etiological agent of Chagas disease. Infection is often subclinical, but severe disease has been described in both free-ranging and captive primates. Panstrongylus megistus, a major T. cruzi vector, was found infesting a small-primate unit at Brasília zoo (ZooB), Brazil. ZooB lies close to a gallery-forest patch where T. cruzi circulates naturally. Here, we combine parasitological and molecular methods to investigate a focus of T. cruzi infection involving triatomine bugs and Neotropical primates at a zoo located in the Brazilian Savannah. METHODS: We assessed T. cruzi infection in vectors using optical microscopy (n = 34) and nested PCR (n = 50). We used quantitative PCR (qPCR) to examine blood samples from 26 primates and necropsy samples from two primates that died during the study. We determined parasite lineages in five vectors and two primates by comparing glucose-6-phosphate isomerase (G6pi) gene sequences. RESULTS: Trypanosoma cruzi was found in 44 vectors and 17 primates (six genera and eight species); one Mico chrysoleucus and one Saguinus niger had high parasitaemias. Trypanosoma cruzi DNA was detected in three primates born to qPCR-negative mothers at ZooB and in the two dead specimens. One Callithrix geoffroyi became qPCR-positive over a two-year follow-up. All G6pi sequences matched T. cruzi lineage TcI. CONCLUSIONS: Our findings strongly suggest vector-borne T. cruzi transmission within a small-primate unit at ZooB - with vectors, and perhaps also parasites, presumably coming from nearby gallery forest. Periodic checks for vectors and parasites would help eliminate T. cruzi transmission foci in captive-animal facilities. This should be of special importance for captive-breeding programs involving endangered mammals, and would reduce the risk of accidental T. cruzi transmission to keepers and veterinarians.


Assuntos
Doença de Chagas/veterinária , Insetos Vetores/parasitologia , Panstrongylus/parasitologia , Primatas/parasitologia , Trypanosoma cruzi/isolamento & purificação , Animais , Animais de Zoológico , Sequência de Bases , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Feminino , Glucose-6-Fosfato Isomerase/genética , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Proteínas de Protozoários/genética , Análise de Sequência de DNA/veterinária , Trypanosoma cruzi/genética
20.
Movimento (Porto Alegre) ; 27: e27016, 2021. tab
Artigo em Português | LILACS | ID: biblio-1287409

RESUMO

Resumo O objetivo do presente estudo foi apresentar e analisar o perfil educacional e esportivo dos atletas de saltos ornamentais que participaram do Troféu Brasil de 2018, mediante utilizaão de um questionário estruturado com base na perspectiva de formação holística para a dupla carreira. Com amostra definida em 15 participantes, a análise exploratória foi conduzida por meio de estatística descritiva no SPSS mediante frequência geral e específica. Os resultados sugerem a compatibilidade entre as formações esportiva e educacional em uma perspectiva denominada trajetórias de transição fluidas, observando-se casos de descontinuação na formação superior. Ressalta-se a carência de uma legislação nacional sobre dupla carreira e de políticas institucionais que promovam o acesso, a permanência e a finalização da formação acadêmica dos atletas de alto rendimento, bem como aponta-se a necessidade de novos estudos com diferentes modalidades a fim de que se aprofunde o debate sobre a dupla carreira esportiva.


Abstract This study aims to present and analyze the sporting and educational profile of fancy diving athletes who participated in the 2018 Brazil Tournament (Troféu Brasil). It uses a questionnaire based on the holistic training model for a dual career. Exploratory analysis was conducted with a sample of 15 individuals, using descriptive statistics on the Statistical Package for the Social Sciences (SPSS) software according to general and specific frequency. The results suggest that sporting and educational training are compatible under a perspective called fluid transition pathways, with cases of higher education discontinuation. The study underscores the lack of legislation on dual careers in Brazil as well as institutional policies that promote access, continuation and completion of academic education for high-performance athletes. Moreover, it points out the need for new studies to expand the debate on dual careers in sports.


Resumen El objetivo de este estudio fue presentar y analizar el perfil, educacional y deportivo, de los atletas de saltos ornamentales que participaron en el Trofeo Brasil de 2018, utilizando un cuestionario estructurado basado en la perspectiva de la formación holística para el doble grado universitario. Con una muestra definida en 15 participantes, el análisis exploratorio fue conducido a través de estadística descriptiva en el software Statistical Package for the Social Sciences (SPSS) mediante frecuencia general y específica. Los resultados sugieren la compatibilidad entre las formaciones deportiva y educativa en una perspectiva denominada trayectorias de transición fluidas y se observaron casos de discontinuidad en la educación superior. Se destaca la falta de una legislación nacional sobre el doble grado y de políticas institucionales que promuevan el acceso, permanencia y finalización de la formación académica de los atletas de alto rendimiento, así como la necesidad de que se realicen nuevos estudios con diferentes modalidades para que se profundice el debate sobre el doble grado deportivo.


Assuntos
Humanos , Masculino , Feminino , Esportes , Atletas , Mobilidade Ocupacional , Educação
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