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1.
Parasitology ; 149(3): 418-426, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34814960

RESUMO

Congenital transmission of Chagas disease plays an important role in endemic countries because it is not a diagnosis that is encountered frequently in prenatal care. Due to limited information regarding congenital transmission of Trypanosoma cruzi in Mexico, the present study aimed to investigate protozoan infectivity and modulation of immune responses in human placental explants infected with T. cruzi Ia Mexican strains. The Inc-5 strain showed increased infectivity and modulated IL-1ß, IL-10 and TLR-4, decreasing their expression after 24 h of infection. Both strains (Inc-5 and Ninoa) stimulated the production of TNF-α and decreased IL-6 levels 96 h after infection. An important detachment of the syncytiotrophoblast caused by infection with T. cruzi was observed after 24 h of infection. In this study, ex vivo infection of human placental villi was performed to better understand interactions involving parasitic T. cruzi and human placental tissue. It was concluded that the strains of TcIa present parasitism in placental tissue, modulation of the innate immune system of the placenta, and cause intense detachment of the syncytiotrophoblast, a fact that may be more associated with abortion and premature birth events than the congenital transmission itself, justifying the low rate of this transmission mechanism by this genotype.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Animais , Doença de Chagas/parasitologia , Feminino , Humanos , México , Placenta/parasitologia , Gravidez , Trypanosoma cruzi/fisiologia
2.
Parasitology ; 146(8): 1063-1074, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31046857

RESUMO

Chagas Disease is a zoonosis caused by the parasite Trypanosoma cruzi. Several high-resolution markers have subdivided T. cruzi taxon into at least seven lineages or Discrete Typing Units (DTUs) (TcI-TcVI and TcBat). Trypanosoma cruzi I is the most diverse and geographically widespread DTU. Recently a TcI genotype related to domestic cycles was proposed and named as TcIDOM. Herein, we combined traditional markers and housekeeping genes and applied a Multispecies Coalescent method to explore intra-TcI relationships, lineage boundaries and genetic diversity in a random set of isolates and DNA sequences retrieved from Genbank from different countries in the Americas. We found further evidence supporting TcIDOM as an independent and emerging genotype of TcI at least in Colombia and Venezuela. We also found evidence of high phylogenetic incongruence between parasite's gene trees (including introgression) and embedded species trees, and a lack of genetic structure among geography and hosts, illustrating the complex dynamics and epidemiology of TcI across the Americas. These findings provide novel insights into T. cruzi systematics and epidemiology and support the need to assess parasite diversity and lineage boundaries through hypothesis testing using different approaches to those traditionally employed, including the Bayesian Multispecies coalescent method.


Assuntos
Variação Genética , Filogenia , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , América Central , DNA de Protozoário/análise , México , América do Sul
3.
Exp Parasitol ; 184: 103-108, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29246832

RESUMO

Experimental Chagas disease has been used as a model to identify several host/parasite interaction factors involved in immune responses to Trypanosoma cruzi infection. One of the factors inherent to this parasite is the complement regulatory protein (Tc-CRP), a major epitope that induces production of lytic antibodies during T. cruzi infections. Previous studies have evaluated the function of Tc-CRP as an antigenic marker via ELISAs, which demonstrated high sensitivity and specificity when compared to other methods. Therefore, this study aimed to assess and compare the levels of lytic antibodies induced by this protein following experimental infection using different T. cruzi strains. Our results demonstrated that infections induced by strains isolated from vectors resulted in subpatent parasitaemia and low reactivity, as assessed by Tc-rCRP ELISAs. On the other hand, mice inoculated with T. cruzi strains isolated from patients developed patent parasitaemia, and presented elevated lytic antibodies titres, as measured by Tc-rCRP ELISA. In addition, comparison between different mouse lineages demonstrated that Balb/c mice were more reactive than C57BL/6 mice in almost all types of infections, except those infected by the AQ-4 strain. Parasites from the Hel strain generated the greatest lytic antibody response in all evaluated models. Therefore, application of sensitive techniques for monitoring immune responses would enable us to establish growth curves for lytic antibodies during the course of the infection, and allow us to discriminate between T. cruzi strains that originate from different hosts.


Assuntos
Anticorpos Antiprotozoários/análise , Antígenos de Protozoários/imunologia , Doença de Chagas/imunologia , Proteínas de Protozoários/imunologia , Trypanosoma cruzi/imunologia , Animais , Biomarcadores/análise , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Insetos Vetores/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Parasitemia/imunologia , Parasitemia/parasitologia , Sensibilidade e Especificidade , Triatominae/parasitologia , Trypanosoma cruzi/classificação
4.
Parasitol Res ; 117(3): 737-746, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29340783

RESUMO

Several bat species can be infected by trypanosomes, but there is not much information about which of these parasites infect bats from Triângulo Mineiro and Alto Paranaíba, Minas Gerais state, Brazil, a formerly endemic region for Trypanosoma cruzi, the causative agent of Chagas disease. The aim of this study was to describe, characterize, and identify the presence of trypanosomes in bats. The captured bats (448) belong to four families and to 19 different species. Of those, 37 bats were found to be positive for trypanosomes by microhematocrit, (infection rate 8.3%) and 27 were positive after hemoculture analysis. Initially, the isolates were identified by PCR (18S rDNA, 24Sα rDNA, spliced leader, COII RFLP-PCR) using primers originally designed for T. cruzi. PCRs (18S rDNA, 24Sα rDNA) showed compatible bands for TcI, whereas COII RFLP-PCR showed a similar pattern associated to TcII. However, there was no DNA amplification using spliced leader as a target, revealing a discrepancy between the results. Phylogenetic analysis of Cathepsin L-like and 18S rDNA sequences proved that 15 of the isolates corresponded to Trypanosoma cruzi marinkellei and one to Trypanosoma dionisii. These results revealed that the diversity of trypanosome species in a region considered endemic for Chagas disease is greater than previous descriptions. All this can confirm the necessity of using DNA sequencing approaches in order to determinate trypanosomes species isolated from bats.


Assuntos
Quirópteros/parasitologia , Trypanosoma/isolamento & purificação , Animais , Brasil/epidemiologia , Catepsina L/genética , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , DNA de Protozoário , DNA Ribossômico/genética , Filogenia , Análise de Sequência de DNA , Trypanosoma/classificação , Trypanosoma/genética , Trypanosoma cruzi/genética
5.
Exp Parasitol ; 170: 66-72, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27614283

RESUMO

Trypanosoma cruzi trypomastigotes are able to resist lysis via the complement system, which involves many surface proteins including the complement regulatory protein (CRP). To examine the diversity in CRP recognition among strains of T. cruzi, the expression levels of the translated protein on trypomastigote surfaces were analyzed by flow cytometry, and associations between protein expression and the biological behavior of these strains, especially the ability to induce lytic antibodies in animal models, were assessed. The highly virulent T. cruzi strains Ninoa, INC-5, and Colombiana and the less virulent strains CL-Brener, LGB-231, and JG were used in the experiments. An expression profile analysis showed that the Colombiana and INC-5 strains have higher translated protein levels and induced higher production of antibodies in mice than the other strains. Our results indicated that there are differences in the surface expression of CRP between parasite strains, with a tendency for the most virulent strains to have higher expression levels. Combined, these results contribute to a better understanding of CRP functions and the complexity of host-parasite interactions, considering the large number of virulence factors involved in the process.


Assuntos
Anticorpos Antiprotozoários/biossíntese , Doença de Chagas/parasitologia , Proteínas do Sistema Complemento/metabolismo , Glicoproteínas de Membrana/biossíntese , Proteínas de Protozoários/biossíntese , Trypanosoma cruzi/patogenicidade , Animais , Doença de Chagas/imunologia , Citometria de Fluxo , Interações Hospedeiro-Parasita , Masculino , Glicoproteínas de Membrana/imunologia , Camundongos , Parasitemia/imunologia , Parasitemia/parasitologia , Proteínas de Protozoários/imunologia , Distribuição Aleatória , Trypanosoma cruzi/imunologia , Virulência
6.
Mediators Inflamm ; 2014: 475946, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25221388

RESUMO

The aim of the present study was to assess the effects of an anticholinesterase agent, pyridostigmine bromide (Pyrido), on experimental chronic Chagas heart disease in mice. To this end, male C57BL/6J mice noninfected (control:Con) or chronically infected (5 months) with Trypanosoma cruzi (chagasic:Chg) were treated or not (NT) with Pyrido for one month. At the end of this period, electrocardiogram (ECG); cardiac autonomic function; heart histopathology; serum cytokines; and the presence of blood and tissue parasites by means of immunohistochemistry and PCR were assessed. In NT-Chg mice, significant changes in the electrocardiographic, autonomic, and cardiac histopathological profiles were observed confirming a chronic inflammatory response. Treatment with Pyrido in Chagasic mice caused a significant reduction of myocardial inflammatory infiltration, fibrosis, and hypertrophy, which was accompanied by a decrease in serum levels of IFNγ with no change in IL-10 levels, suggesting a shift of immune response toward an anti-inflammatory profile. Lower nondifferent numbers of parasite DNA copies were observed in both treated and nontreated chagasic mice. In conclusion, our findings confirm the marked neuroimmunomodulatory role played by the parasympathetic autonomic nervous system in the evolution of the inflammatory-immune response to T. cruzi during experimental chronic Chagas heart disease in mice.


Assuntos
Cardiomiopatias/tratamento farmacológico , Doença de Chagas/tratamento farmacológico , Doença Crônica/tratamento farmacológico , Brometo de Piridostigmina/uso terapêutico , Animais , Cardiomiopatias/metabolismo , Doença de Chagas/metabolismo , Inibidores da Colinesterase/uso terapêutico , Eletrocardiografia , Frequência Cardíaca/efeitos dos fármacos , Interferon gama/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Trypanosoma cruzi/patogenicidade
7.
Parasitol Res ; 113(6): 2199-207, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24728520

RESUMO

Trypanosoma cruzi and Trypanosoma rangeli are kinetoplastid parasites which are able to infect humans in Central and South America. Misdiagnosis between these trypanosomes can be avoided by targeting barcoding sequences or genes of each organism. This work aims to analyze the feasibility of using species-specific markers for identification of intraspecific polymorphisms and as target for diagnostic methods by PCR. Accordingly, primers which are able to specifically detect T. cruzi or T. rangeli genomic DNA were characterized. The use of intergenic regions, generally divergent in the trypanosomatids, and the serine carboxypeptidase gene were successful. Using T. rangeli genomic sequences for the identification of group-specific polymorphisms and a polymorphic AT(n) dinucleotide repeat permitted the classification of the strains into two groups, which are entirely coincident with T. rangeli main lineages, KP1 (+) and KP1 (-), previously determined by kinetoplast DNA (kDNA) characterization. The sequences analyzed totalize 622 bp (382 bp represent a hypothetical protein sequence, and 240 bp represent an anonymous sequence), and of these, 581 (93.3%) are conserved sites and 41 bp (6.7%) are polymorphic, with 9 transitions (21.9%), 2 transversions (4.9%), and 30 (73.2%) insertion/deletion events. Taken together, the species-specific markers analyzed may be useful for the development of new strategies for the accurate diagnosis of infections. Furthermore, the identification of T. rangeli polymorphisms has a direct impact in the understanding of the population structure of this parasite.


Assuntos
Trypanosoma cruzi/genética , Trypanosoma rangeli/genética , Tripanossomíase/parasitologia , Sequência de Bases , Clonagem Molecular , DNA de Protozoário/genética , Marcadores Genéticos , Humanos , Repetições de Microssatélites , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Especificidade da Espécie , Trypanosoma cruzi/classificação , Trypanosoma rangeli/classificação , Tripanossomíase/diagnóstico
8.
Parasitol Res ; 112(2): 671-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23160891

RESUMO

The congenital transmission of Chagas disease is associated with an increase in parasitemia during pregnancy, maternal and fetal immunity, and populations of Trypanosoma cruzi. In this study, the biological behavior of TcI and TcV (isolated from a human congenital case) strains and their potential for experimental congenital transmission were evaluated in female BALB/C mice. Parasitemia was estimated by fresh blood examination, semiquantitative microhematocrit, and hemoculture, while congenital transmission was evaluated by culture in the liver infusion tryptose medium and by polymerase chain reaction (PCR) of the pups' tissues on postnatal day 7 and of the pups' blood sample at 30 days after birth. Infection was detected in 100 % of the females. Both strains showed subpatent parasitemia, which was higher for TcV infection. The presence of amastigote nest was detected only in an animal infected with TcI. The inflammatory process was more frequent (p = 0.001) in the tissues of the animals infected with TcV (58.6 %) than TcI (31.1 %). The fertility rates of females mated after 35 days postinfection were similar (90 % for TcV, 88.9 % for TcI; p = 0.938). Parasitemia did not change during pregnancy. The average number of pups/female was greater (p = 0.03) in mice with TcV infection (8.30) than in those with TcI infection (4.78). Congenital transmission was detected exclusively by PCR in 50.9 % of the pups, 46.6 % for TcV and 58.1 % for TcI. The PCR positivity for TcI was higher in the blood than in the tissue (p = 0.003). These results demonstrate the T. cruzi experimental congenital infection associated with subpatent maternal parasitemia of TcI and TcV.


Assuntos
Doença de Chagas/congênito , Doença de Chagas/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Trypanosoma cruzi/isolamento & purificação , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Parasitemia/parasitologia , Gravidez , Trypanosoma cruzi/genética
9.
Respir Med Case Rep ; 45: 101910, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663528

RESUMO

Bronchiolitis obliterans (BO) is a progressive fibrotic process that predominantly affects the small airways and is identified as constrictive bronchiolitis by pathologists. It is commonly associated with allogeneic hematopoietic stem cell transplant (HSCT), lung transplant, exposure to inhaled toxins, post-infectious processes, autoimmune diseases, and sometimes, no known cause. In the latter case, it is referred to as cryptogenic bronchiolitis obliterans. A 52-year-old Hispanic man with a medical history of hypertension, diabetes mellitus, and coronary artery disease was referred to the pulmonary department due to experiencing dyspnea on exertion, intermittent dry cough, and progressive limitation of activities of daily living. Spirometry revealed severe obstructive changes, and chest high-resolution computed tomography showed ground-glass opacities with nodular infiltrates in the upper lobes, leading to a presumptive diagnosis of hypersensitivity pneumonitis. The patient underwent a lung surgical biopsy of the right upper and lower lobes, which revealed extensive constrictive bronchiolitis. Due to the patient's worsening general condition, bilateral lung transplantation succeeded without any further complications. Following the transplantation, the patient showed good recovery and functional improvement. Bronchiolitis obliterans, or constrictive bronchiolitis, has a variable natural history. It is associated with a higher risk of mortality in allogenic HSCT. When BO is secondary to inhalation of toxic gases, it is usually nonprogressive and limited to toxin exposure. Autoimmune diseases or cryptogenic bronchiolitis are rare and have a heterogeneous clinical course. To make a proper diagnosis, clinical history, radiologic and histologic findings must be considered.

10.
Exp Physiol ; 97(11): 1186-202, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22707503

RESUMO

The aim of the present study was to evaluate the effects of changes to the autonomic nervous system in mice during the acute phase of Chagas disease, which is an infection caused by the parasite Trypanosoma cruzi. The following types of mice were inoculated with T. cruzi (CHG): wild-type (WT) and vesicular acetylcholine transporter knockdown (KDVAChT) C57BL/6j mice; wild-type non-treated (NT) FVB mice; FVB mice treated with pyridostigmine bromide (PYR) or salbutamol (SALB); and ß(2)-adrenergic receptor knockout (KOß2) FVB mice. During infection and at 18-21 days after infection (acute phase), the survival curves, parasitaemia, electrocardiograms, heart rate variability, autonomic tonus and histopathology of the animals were evaluated. Negative control groups were matched for age, genetic background and treatment. The KDVAChT-CHG mice exhibited a significant shift in the electrocardiographic, autonomic and histopathological profiles towards a greater inflammatory immune response that was associated with a reduction in blood and tissue parasitism. In contrast, the CHG-PYR mice manifested reduced myocardial inflammation and lower blood and tissue parasitism. Similar results were observed in CHG-SALB animals. Unexpectedly, the KOß2-CHG mice exhibited less myocardial inflammation and higher blood and tissue parasitism, which were associated with reduced mortality. These findings could have been due to the increase in vagal tone observed in the KOß2 mice, which rendered them more similar to the CHG-PYR animals. In conclusion, our results indicate a marked immunomodulatory role for the parasympathetic and sympathetic autonomic nervous systems, which inhibit both the inflammatory immune response and parasite clearance during the acute phase of experimental Chagas heart disease in mice.


Assuntos
Doença de Chagas/imunologia , Doença de Chagas/fisiopatologia , Inflamação/imunologia , Inflamação/fisiopatologia , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Doença Aguda , Animais , Atenolol/farmacologia , Doença de Chagas/metabolismo , Doença de Chagas/parasitologia , Eletrocardiografia/métodos , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Inflamação/metabolismo , Inflamação/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Parasitemia/imunologia , Parasitemia/metabolismo , Parasitemia/parasitologia , Parasitemia/fisiopatologia , Sistema Nervoso Parassimpático/efeitos dos fármacos , Sistema Nervoso Parassimpático/imunologia , Sistema Nervoso Parassimpático/metabolismo , Propranolol/farmacologia , Brometo de Piridostigmina/farmacologia , Receptores Adrenérgicos beta 2/metabolismo , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/imunologia , Sistema Nervoso Simpático/metabolismo
11.
Parasitol Res ; 108(2): 459-66, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20886234

RESUMO

The aim of this study was to investigate the genetic variability of sequences present in the chromosome ends of Trypanosoma rangeli strains defined by the presence (+) or absence (-) of KP1 minicircles, and to compare the mean terminal restriction fragment (TRF) lengths to those of Trypanosoma cruzi populations representative of groups TcI, TcII, TcIV, and TcVI. Southern blots containing RsaI-digested genomic DNA of T. rangeli KP1(+) strains, T. rangeli KP1(-) strains, and T. cruzi strains were probed with the previously described subtelomeric sequences (170 bp) of T. rangeli and with telomeric hexamer repeats. Mean TRF length analysis showed that the chromosome ends of T. rangeli are distinctly organized, with TRFs ranging from 1.3 to 9 kb for KP1(+) strains and from 0.3 to 5.0 kb for KP1(-) strains. In T. cruzi, TRF length ranged from 0.2 to 9 kb and no association with the genotype of the parasite could be established. Sequence analysis of the 170-bp amplicons revealed the occurrence of sequence polymorphisms in the subtelomeric region between and within KP1(+) and KP1(-) strains. The GTT triplet was detected in all KP1(+) strains, except for strain Cas4, but not in any of the KP1(-) strains. The dendrogram constructed by alignment of all T. rangeli strains showed the division into two main groups, mainly related to the presence or absence of the KP1 minicircle. In conclusion, the present results extend the genotype differences demonstrated by kDNA and karyotype analysis in T. rangeli to the chromosome ends of the parasite.


Assuntos
Cromossomos/genética , DNA de Protozoário/análise , Genes de Helmintos , Trypanosoma cruzi/genética , Trypanosoma rangeli/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Variação Genética , Genômica , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie , Trypanosoma cruzi/classificação , Trypanosoma rangeli/classificação
12.
Ann Diagn Pathol ; 14(3): 199-203, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20471566

RESUMO

Transplanted organs may act as a route of transmission of infectious diseases, such as Chagas' disease. The aim of this study was to describe the transmission of the Trypanosoma cruzi through a renal transplant and the anatomo-clinical evolution of the patient after treatment with benzonidazole. The patient was a 31-year-old white male from the State of Minas Gerais in Brazil. He had renal failure secondary to diabetes and later received a kidney from a cadaveric donor. The patient was undergoing immunosuppression therapy with azathioprine, cyclosporine A, and prednisone. After the transplant, he developed an acute phase of Chagas' disease and complications from diabetes and died 2 months later. In the autopsy, T cruzi amastigotes were found in the transplanted kidney, heart, bladder, liver, and pancreas. An important reduction in the parasitemia was obtained through the treatment of the infection with benzonidazole; however, the patient died due to complications from diabetes associated with tissue lesions caused by T cruzi.


Assuntos
Doença de Chagas/etiologia , Transplante de Rim/efeitos adversos , Nitroimidazóis/uso terapêutico , Complicações Pós-Operatórias , Tripanossomicidas/uso terapêutico , Doença Aguda , Adulto , Doença de Chagas/tratamento farmacológico , Doença de Chagas/patologia , Evolução Fatal , Humanos , Hospedeiro Imunocomprometido , Terapia de Imunossupressão/efeitos adversos , Imunossupressores/uso terapêutico , Masculino , Insuficiência Renal/cirurgia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/fisiologia
13.
Vector Borne Zoonotic Dis ; 20(2): 117-124, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31638479

RESUMO

Trypanosoma rangeli is an avirulent flagellate protozoan that could mislead correct diagnosis of Trypanosoma cruzi infection, the causative agent of Chagas' disease, given their high similarity. Besides, T. rangeli presents two genetic groups, whose differentiation is achieved mainly by molecular approaches. In this context, ribosomal DNA (rDNA) is a useful target for intra and interspecific molecular differentiation. Analyzing the rDNA of T. rangeli and comparison with other trypanosomatid species, two highly divergent regions (Trß1 and Trß2) within the 28Sß gene were found. Those regions were amplified and sequenced in KP1(+) and KP1(-) strains of T. rangeli, revealing group-specific polymorphisms useful for intraspecific distinction through restriction fragment length polymorphism technique. Also, amplification of Trß1 allowed differentiation between T. rangeli and T. cruzi. Trß2 predicted restriction length profile, allowed differentiation between T. rangeli, T. cruzi, Trypanosoma brucei, and Leishmania braziliensis, increasing the use of Trß1 and Trß2 beyond a molecular approach for T. rangeli genotyping, but also as a useful target for trypanosomatid classification.


Assuntos
DNA Ribossômico , Trypanosoma rangeli/classificação , Trypanosoma rangeli/genética , DNA de Protozoário/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Especificidade da Espécie , Trypanosoma/classificação , Trypanosoma/genética , Trypanosoma cruzi/genética
14.
Ann Diagn Pathol ; 12(4): 271-274, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18620994

RESUMO

Chagasic visceromegalies are the most important digestive manifestations of Chagas disease and are characterized by motor disorders and dilation of organs such as esophagus and colon. One of the theories raised to explain the physiopathogenesis of chagasic megas is the plexus theory. Recent studies have shown a reduction of interstitial cells of Cajal (ICCs) in the colon of chagasic patients. These cells are present throughout the gastrointestinal tract and are considered to be pacemaker cells, that is, they are responsible for coordinating peristalsis and for mediating nerve impulses. In view of the lack of studies on these cells in megaesophagus and the previous observation of a reduction of ICCs in chagasic megacolons, we compared the distribution of ICCs in the esophagus of chagasic and nonchagasic patients to contribute to a better understanding of the physiopathogenesis of this esophageal disease. Esophageal biopsy samples from 10 chagasic and 5 nonchagasic patients were used. Cells were identified with the anti-CD117 antibody. The number of ICCs was quantified in longitudinal and circular muscle layers and myenteric plexus. The results were analyzed statistically by comparison of means. An intense reduction in the number of ICCs was observed in muscle layers and in the myenteric plexus of patients with megaesophagus. We conclude that there is an intense reduction of ICCs in the esophagus of chagasic patients when compared to nonchagasic patients, a finding supporting the important role of these cells in gastrointestinal tract motility. A deficiency in these cells might be implied in the genesis of megaesophagus.


Assuntos
Doença de Chagas/complicações , Acalasia Esofágica/etiologia , Esôfago/patologia , Contagem de Células , Doença de Chagas/patologia , Acalasia Esofágica/patologia , Humanos , Imuno-Histoquímica , Músculo Liso/patologia , Plexo Mientérico/patologia
15.
Rev Soc Bras Med Trop ; 41(3): 257-62, 2008.
Artigo em Português | MEDLINE | ID: mdl-18719805

RESUMO

The physical and geographical characteristics of the Ciénega region, Jalisco, Mexico make it suitable for transmission of Trypanosoma cruzi, the causative agent for Chagas disease. This study characterizes the prevalence of triatomines infected by this parasite, their seasonality and their distribution in this region. A total of 328 triatomines were evaluated between January 2005 and June 2007, from 13 municipalities in the region. April, May and June were the months with the highest capture levels. Among the triatomines examined, 57.3% were positive for Trypanosoma cruzi, corresponding to 15.4% in urban areas and 84.6% in rural areas. The species with greatest prevalence was Triatoma longipennis and the species with the highest parasitism rate was Triatoma barberi, with an infection rate of 83.3%, whereas the rate for Triatoma longipennis was 67.5% (p<0.05). This natural infection in the captured vectors may indicate that individuals in this region have high exposure to Trypanosoma cruzi. The recent findings of positive Triatoma dimidiata in this region suggest that new species are becoming adapted to the ecological conditions of these populations.


Assuntos
Insetos Vetores/classificação , Triatominae , Trypanosoma cruzi/isolamento & purificação , Animais , Doença de Chagas/transmissão , Insetos Vetores/parasitologia , México , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Triatominae/classificação , Triatominae/parasitologia
16.
Rev Soc Bras Med Trop ; 41(2): 152-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18545835

RESUMO

This study evaluated the possibility of inoculation and reinoculation with a trypanosomatid isolated from bats that is morphologically, biologically and molecularly similar to Trypanosoma cruzi, to protect against infection by virulent strains. Non-isogenic mice were divided into 24 groups that received from zero to three inoculations of Trypanosoma cruzi-like strain RM1, in the presence or absence of Freunds adjuvant, and were challenged with the VIC or JG strains of Trypanosoma cruzi. Parasitemia and survival were monitored and animals were sacrificed for histopathological analysis. Animals immunized with Trypanosoma cruzi-like strain RM1 presented decreased parasitemia, independently of the number of inoculations or the presence of adjuvant. In spite of this reduction, these animals did not present any protection against histopathological lesions. Severe eosinophilic infiltrate was observed and was correlated with the number of inoculations of Trypanosoma cruzi-like strain RM1. These findings suggest that prior inoculation with this strain did not protect against infection but, rather, aggravated the tissue inflammatory process.


Assuntos
Doença de Chagas/imunologia , Eosinofilia/imunologia , Soros Imunes/imunologia , Imunização Passiva/métodos , Parasitemia/imunologia , Trypanosoma cruzi/imunologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Doença de Chagas/prevenção & controle , Quirópteros/parasitologia , Reações Cruzadas/imunologia , Eosinofilia/parasitologia , Adjuvante de Freund/uso terapêutico , Soros Imunes/administração & dosagem , Camundongos , Parasitemia/parasitologia , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/patogenicidade
17.
Rev Assoc Med Bras (1992) ; 64(3): 281-289, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29641786

RESUMO

Leishmaniasis is a disease with ample clinical spectrum and epidemiological diversity and is considered a major public health problem. This article presents an overview of the transmission cycles, host-parasite interactions, clinical, histological and immunological aspects, diagnosis and treatment of various forms of the human disease.


Assuntos
Leishmaniose/epidemiologia , Animais , Antiprotozoários/uso terapêutico , Brasil/epidemiologia , Interações Hospedeiro-Parasita/fisiologia , Humanos , Leishmania/fisiologia , Leishmaniose/tratamento farmacológico , Leishmaniose/fisiopatologia , Psychodidae/parasitologia
18.
Rev. colomb. neumol ; 35(2): 35-39, 05/12/2023.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1551149

RESUMO

La incidencia de infección por micobacterias no tuberculosas (MNT) y el número de casos han ido en aumento, especialmente en mujeres y personas mayores, teniendo en los Estados Unidos entre el 2008 y 2015 una incidencia de 4.16 a 6.69 por 100000 entre las mujeres y de 12.70 a 18.37 por 100000, entre los mayores de 65 años. "Los pacientes con compromiso estructural del parénquima pulmonar, antecedente de inmunosupresión o inmunodeficiencia tienen mayor riesgo de desarrollar infección por MNT". Sin embargo, se han presentado informes de pacientes inmunocompetentes en asociación con opacidades nodulares y bronquiectasias. Se trata de una mujer de 79 años con antecedente de tuberculosis pulmonar documentada en dos oportunidades: último proceso infeccioso en el año 2021. Recibió manejo por seis meses de esquema vigente con tetraconjugado. Actualmente acude a consulta con cuadro clínico de más de seis meses de evolución dados por pérdida de peso de más del 10 % en un año, disnea a moderados esfuerzos y tos con expectoración purulenta. Al examen físico se encontró índice de masa corporal (IMC) bajo, tórax hipoexpansible con estertores tipo crépitos en ambos hemitórax. En la tomografía de tórax se evidenciaron bronquiectasias generalizadas, algunas áreas de árbol en gemación y lesiones cavitadas. Se consideró la realización de fibrobroncoscopia con lavado broncoalveolar documentándose baciloscopias negativas, con cultivo positivo para micobacteria no tuberculosa. Se solicitó tipificación de micobacterias con coloración de Kinyoun, y pruebas bioquímicas a partir de cepas de cultivo del lavado broncoalveolar, con reporte positivo para Mycobacterium intracellulare. Se inició por lo tanto manejo con azitromicina 500 mg, rifampicina 600 mg y etambutol 975 mg diarios. Los profesionales sanitarios deben ser conscientes de la posible infección por MNT sobre todo existiendo afectación estructural pulmonar previa, basando el tratamiento en la sospecha clínica y/o las circunstancias epidemiológicas.


The incidence of non-tuberculous mycobacterial (NTM) infection and the number of cases have been increasing, especially in women and the elderly, having EE. Between 2008 and 2015 an incidence of 4.16 to 6.69 per 100,000 among women and from 12.70 to 18.37 per 100,000 among those over 65. "Patients with structural involvement of the pulmonary parenchyma, history of immunosuppression or immunodeficiency have a higher risk of developing NTM infection". However, immunocompetent patients have been reported in association with nodular opacities and bronchiectasis. This is a 79-year-old woman with a history of pulmonary tuberculosis documented on 2 occasions: the last infectious process in 2021. It received management for 6 months of the current tetraconjugate schema. He is currently in consultation with a clinical picture of more than 6 months of evolution given by weight loss of more than 10% in a year, dyspnea to moderate efforts and cough with purulent expectoration. Physical examination revealed low body mass index (BMI) and, a hypoexpandable thorax with a crescent-like sternum in both hemithorax. Chest tomography revealed widespread bronchiectasis, some groaning tree areas and cavitated lesions. Bronchoscopy fibro bronchoscopy with bronchoalveolar lavage has been reported negative bacilloscopies, positive culture for non-tuberculosis mycobacteria. Mycobacteria typing, Kinyoun coloration, and biochemical tests were requested from bronchoalveolar lavage culture strains with positive reports for Mycobacterium intracellulare. Management was therefore initiated with azithromycin 500 mg, rifampin 600 mg and ethambutol 975mg daily. Healthcare professionals should be aware of possible NTM infection especially existing prior lung structural involvement based on clinical suspicion and/or epidemiological circumstances.

20.
PLoS One ; 12(12): e0189907, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29261763

RESUMO

Trypanosoma cruzi, a human protozoan parasite, is the causative agent of Chagas disease. Currently the species is divided into six taxonomic groups. The genome of the CL Brener clone has been estimated to be 106.4-110.7 Mb, and DNA content analyses revealed that it is a diploid hybrid clone. Trypanosoma rangeli is a hemoflagellate that has the same reservoirs and vectors as T. cruzi; however, it is non-pathogenic to vertebrate hosts. The haploid genome of T. rangeli was previously estimated to be 24 Mb. The parasitic strains of T. rangeli are divided into KP1(+) and KP1(-). Thus, the objective of this study was to investigate the DNA content in different strains of T. cruzi and T. rangeli by flow cytometry. All T. cruzi and T. rangeli strains yielded cell cycle profiles with clearly identifiable G1-0 (2n) and G2-M (4n) peaks. T. cruzi and T. rangeli genome sizes were estimated using the clone CL Brener and the Leishmania major CC1 as reference cell lines because their genome sequences have been previously determined. The DNA content of T. cruzi strains ranged from 87,41 to 108,16 Mb, and the DNA content of T. rangeli strains ranged from 63,25 Mb to 68,66 Mb. No differences in DNA content were observed between KP1(+) and KP1(-) T. rangeli strains. Cultures containing mixtures of the epimastigote forms of T. cruzi and T. rangeli strains resulted in cell cycle profiles with distinct G1 peaks for strains of each species. These results demonstrate that DNA content analysis by flow cytometry is a reliable technique for discrimination between T. cruzi and T. rangeli isolated from different hosts.


Assuntos
DNA de Protozoário/análise , Trypanosoma cruzi/genética , Trypanosoma rangeli/genética , Animais , Citometria de Fluxo , Genoma de Protozoário
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