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1.
PLoS Negl Trop Dis ; 14(9): e0008608, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925918

RESUMO

The receptor Signaling Lymphocyte-Activation Molecule Family 1 (SLAMF1) controls susceptibility to Infection by the lethal Trypanosoma cruzi Y strain. To elucidate whether genetic diversity of the parasite was related with disease susceptibility, we further analyzed the role of SLAMF1 using 6 different Trypanosoma cruzi strains including Y. The interaction of SLAMF1 receptor with T. cruzi was evidenced by fluorescence microscopy, flow cytometry and quantitative PCR. All the strains, except VFRA, showed a decrease in parasite load in infected macrophages in Slamf1-/- compared to BALB/c. In macrophages gene expression NADPH oxidase (NOX2), and reactive oxygen species (ROS) production increased in Slamf1-/- compared to BALB/c in 5 out of 6 strains. However, Slamf1-/-macrophages infected with VFRA strain exhibited a divergent behavior, with higher parasite load, lower NOX2 expression and ROS production compared to BALB/c. Parasitological and immunological studies in vivo with Y strain showed that in the absence of SLAMF1 the immune response protected mice from the otherwise lethal Y infection favoring a proinflammatory response likely involving CD4, CD8, dendritic cells and classically activated macrophages. In the case of VFRA, no major changes were observed in the absence of SLAMF1. Thus, the results suggest that the T. cruzi affects SLAMF1-dependent ROS production, controlling parasite replication in macrophages and affecting survival in mice in a strain-dependent manner. Further studies will focus in the identification of parasite molecules involved in SLAMF1 interaction to explain the immunopathogenesis of the disease.


Assuntos
Macrófagos/parasitologia , Espécies Reativas de Oxigênio/metabolismo , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária/genética , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo , Trypanosoma cruzi/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Doença de Chagas/imunologia , Chlorocebus aethiops , Células Dendríticas/imunologia , Suscetibilidade a Doenças/imunologia , Células HEK293 , Coração/parasitologia , Humanos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Miocárdio/patologia , NADPH Oxidase 2/genética , NADPH Oxidase 2/metabolismo , Carga Parasitária , Células Vero
2.
Ann Parasitol ; 66(2): 255-257, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32592549

RESUMO

The aim of this study was to recognise the etiological factor of a disease with symptoms of lameness and cardiac failure, which occurred in one dog 4 weeks after invasion by ticks. A serological examination as well as molecular examination (PCR) was done. In the sample of the serum, the presence of antibodies specific to Borrelia burgdorferi were detected. Antibiotic therapy with doxycycline did not cause significant improvement, so the owners of the dog decided about its euthanasia. During the necroscopy, a dilated heart was recognised. In the heart samples, the genetic material of Borrelia was detected. The results of serological and molecular examinations showed that in the discussed case, an etiological factor of the disease was spirochetes. In light of the research, veterinary practitioners should keep in mind the presence of Lyme disease in dogs in Poland and include it in differential diagnoses for lameness and cardiological problems.


Assuntos
Infecções por Borrelia , Doenças do Cão , Miocardite , Infestações por Carrapato , Animais , Anticorpos Antibacterianos/sangue , Infecções por Borrelia/complicações , Infecções por Borrelia/diagnóstico , Doenças do Cão/diagnóstico , Doenças do Cão/etiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Eutanásia Animal , Coração/parasitologia , Miocardite/diagnóstico , Miocardite/etiologia , Polônia , Infestações por Carrapato/complicações , Infestações por Carrapato/microbiologia , Infestações por Carrapato/veterinária
3.
J Parasitol ; 106(3): 323-333, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32369594

RESUMO

Benznidazole and nifurtimox are the only drugs specifically approved for the treatment of Chagas disease. Both compounds are given orally in tablets, but occasionally are ineffective and cause adverse effects. Benznidazole, the first-line treatment in many countries, is a compound with low solubility in water that is administered at high doses for long periods of time. To improve its solubility, we developed a new liquid formulation on the basis of solid dispersions (SD) using the amphiphilic polymer poloxamer 407. Herein we present data on its trypanocidal performance in mouse models of acute and chronic Trypanosoma cruzi infection. SD at doses of 60 or 15 mg/kg per day given with different administration schedules were compared with the commercial formulation (CF; 50 mg/kg per day) and vehicle. The SD performance was assessed by direct parasitemia, total anti-T. cruzi antibodies, and parasitic burden in tissues after 4 or 6 mo posttreatment. The efficacy of the SD was equivalent to the CF but without manifest side effects and hepatotoxicity. Considering our previous data on solubility, together with these on efficacy, this new liquid formulation represents a promising alternative for the treatment of Chagas disease, particularly in cases when dosing poses a challenge, as in infants.


Assuntos
Doença de Chagas/tratamento farmacológico , Excipientes/uso terapêutico , Nitroimidazóis/uso terapêutico , Poloxâmero/uso terapêutico , Tripanossomicidas/uso terapêutico , Doença Aguda , Animais , Anticorpos Antiprotozoários/sangue , Aspartato Aminotransferases/sangue , Doença Crônica , Modelos Animais de Doenças , Feminino , Coração/parasitologia , Camundongos , Miocárdio/patologia , Parasitemia , Músculo Quadríceps/parasitologia , Músculo Quadríceps/patologia , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Trypanosoma cruzi/imunologia
4.
Int J Food Microbiol ; 322: 108563, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32113068

RESUMO

Toxoplasmosis is one of the most common foodborne diseases in the world. The objective of this study was to determine Toxoplasma gondii infection in lambs from Henan province, China. A total of 166 lamb hearts were collected from 2017 to 2019. T. gondii infection was determined by the Modified Agglutination Test (MAT) using heart juice of lambs. 11 isolates (TgSheepCHn3 - TgSheepCHn13) were obtained from samples with MAT titers ≥1:100. The rate of T. gondii isolation increased with antibody titer against T. gondii (P < 0.05). No isolate was obtained from samples with titer 1:25 and 1:50, suggesting the cut-off titer for MAT is better set at 1:100. With cut-off value of 1:100, IgG antibodies to T. gondii were found in 25.3% (42/166) of the lambs by MAT. T. gondii parasite was not found in IHC and HE-stained tissue sections of lamb hearts (0/166). Sixty-seven heart tissues with ≥1:25 MAT titers were subjected to acid pepsin digestion and detected T. gondii by PCR. Only 7.5% (5/67) of DNA amplified products were found in heart tissues by the primer TOX5/TOX8. Brain tissue cysts were observed in all mice infected with the 11 isolates at day 60 post infection, suggesting these isolates are non-lethal to mice. PCR-RFLP analysis revealed that 7 isolates belonged to ToxoDB#2, 4 isolates belonged to ToxoDB#4. This is the first isolation of ToxoDB#2 and ToxoDB#4 from lambs in China. Interestingly, none of these isolates belongs to the ToxoDB#9 that is common in China. Our results suggest that the genetic diversity and population structure of T. gondii from China maybe more abundant and magical than previous speculation.


Assuntos
Coração/parasitologia , Carne Vermelha/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , China/epidemiologia , Genótipo , Camundongos , Carneiro Doméstico , Toxoplasma/imunologia , Toxoplasma/patogenicidade , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/patologia
5.
Parasitol Res ; 119(6): 1829-1843, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32206887

RESUMO

The underlying pathogenic mechanisms of cardiomyopathy in Chagas disease are still unsolved. In order to better clarify the role of fat on the evolution of cardiomyopathy, the present study employed three murine models of chronic Trypanosoma cruzi infection: (1) aP2-RIDα/ß transgenic mice (RID mice; an adipose tissue model which express a gain-of-function potent anti-inflammatory activity), (2) allograft inflammatory factor-1 knockout mice (Aif1-/-), and (3) a Swiss outbred mice. RID mice and non-transgenic mice (wild type, WT) were infected with blood trypomastigotes of Brazil strain. During the acute stage of infection, RID mice had lower parasitemia, lower heart inflammation, and a decrease in the relative distribution of parasite load from cardiac muscle tissue toward epididymal fat. Nevertheless, comparable profiles of myocardial inflammatory infiltrates and relative distribution of parasite load were observed among RID and WT at the chronic stage of infection. Aif1-/- and Aif1+/+ mice were infected with bloodstream trypomastigotes of Tulahuen strain and fed with high-fat diet (HFD) or regular diet (RD). Interestingly, Aif1+/+ HFD infected mice showed the highest mortality. Swiss mice infected with blood trypomastigotes of Berenice-78 strain on a HFD had higher levels of TNFα and more inflammation in their heart tissue than infected mice fed a RD. These various murine models implicate adipocytes in the pathogenesis of chronic Chagas disease and suggest that HFD can lead to a significant increase in the severity of parasite-induced chronic cardiac damage. Furthermore, these data implicate adipocyte TLR4-, TNFα-, and IL-1ß-mediated signaling in pro-inflammatory pathways and Aif-1 gene expression in the development of chronic Chagas disease.


Assuntos
Cardiomiopatia Chagásica/patologia , Doença de Chagas/complicações , Dieta Hiperlipídica , Trypanosoma cruzi , Animais , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/parasitologia , Doença de Chagas/patologia , Modelos Animais de Doenças , Feminino , Coração/parasitologia , Inflamação/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Miocárdio/patologia , Carga Parasitária , Trypanosoma cruzi/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
6.
Malar J ; 19(1): 69, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050970

RESUMO

BACKGROUND: Passerine birds are frequently infected with diverse haemosporidian parasites. While infections are traditionally considered benign in wild birds, recent studies demonstrated mortalities of passerine species due to exo-erythrocytic development of the parasites, which can damage organs in affected hosts. However, exo-erythrocytic development remains insufficiently investigated for most haemosporidian species and thus little is known about the virulence of tissue stages in wild passerine birds. The aim of the present study was to investigate natural haemosporidian infections in deceased Eurasian blackbirds (Turdus merula) and song thrushes (Turdus philomelos) and to determine parasite burden and associated histological effects. METHODS: For molecular analysis, blood and tissue samples from 306 thrushes were screened for Plasmodium, Haemoproteus and Leucocytozoon parasites by nested PCR. For the detection of parasite stages in organ samples, tissue sections were subjected to chromogenic in situ hybridization (CISH) using genus- and species-specific probes targeting the rRNAs of parasites. Exo-erythrocytic parasite burden was semi-quantitatively assessed and histological lesions were evaluated in haematoxylin-eosin-stained sections. RESULTS: By PCR, 179 of 277 Eurasian blackbirds and 15 of 29 song thrushes were positive for haemosporidians. Parasites of all three genera were detected, with Plasmodium matutinum LINN1 and Plasmodium vaughani SYAT05 showing the highest prevalence. CISH revealed significant differences in exo-erythrocytic parasite burden between lineages in Eurasian blackbirds, with P. matutinum LINN1 frequently causing high exo-erythrocytic parasite burdens in various organs that were associated with histological alterations. Song thrushes infected with P. matutinum LINN1 and birds infected with other haemosporidian lineages showed mostly low exo-erythrocytic parasite burdens. Two Eurasian blackbirds infected with Leucocytozoon sp. TUMER01 showed megalomeronts in various organs that were associated with inflammatory reactions and necroses. CONCLUSION: This study suggests that P. matutinum LINN1, a common lineage among native thrushes, regularly causes high exo-erythrocytic parasite burdens in Eurasian blackbirds, which may result in disease and mortalities, indicating its high pathogenic potential. The findings further illustrate that the same parasite lineage may show different levels of virulence in related bird species which should be considered when assessing the pathogenicity of haemosporidian parasite species. Finally, the study provides evidence of virulent Leucocytozoon sp. TUMER01 infections in two Eurasian blackbirds caused by megalomeront formation.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/fisiologia , Infecções Protozoárias em Animais/parasitologia , Aves Canoras/parasitologia , Animais , Animais Selvagens , Áustria , Bolsa de Fabricius/parasitologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Haemosporida/genética , Haemosporida/isolamento & purificação , Haemosporida/patogenicidade , Coração/parasitologia , Hibridização In Situ/métodos , Hibridização In Situ/veterinária , Rim/parasitologia , Plasmodium/classificação , Plasmodium/genética , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Especificidade da Espécie , Virulência
7.
Vet Parasitol ; 278: 109014, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31972512

RESUMO

Trypanosoma cruzi is a zoonotic protozoan parasite transmitted by triatomines that infects a wide range of mammals. South Texas is a hotspot for triatomines, T. cruzi-infected dogs and wildlife, and local transmission to humans also occurs. However, little is known about the infection of domestic cats (Felis catus) in the United States. Given the role cats play in the ecology of T. cruzi in Mexico and South America, we hypothesized that T. cruzi infection occurs in cats from south Texas, sometimes associated with cardiac pathology. In 2017, 167 euthanized cats from a south Texas shelter were sampled across winter, spring, and summer. We collected whole blood and hearts from all cats, with additional tissues from a subset. Serum samples were screened for T. cruzi antibodies using two independent rapid immunochromatographic tests and an indirect fluorescent antibody test. Cats were considered seropositive if they were positive on at least two independent serological tests. Blood clot, heart tissue and other tissues were subjected to qPCR for parasite detection and discrete typing unit (DTU) determination. Tissues from selected seropositive or PCR-positive animals and a subset of negative animals were processed routinely for histopathology and examined by a board-certified pathologist. A total of 19 cats (11.4%) were seropositive and three cats (1.8%) - one of which was seropositive - had one or more PCR-positive tissues. Infected tissues included heart, bicep femoris muscle, sciatic nerve, esophagus, and mesentery. Genotyping of the parastite to the level of DTU showed that exclusively DTU TcI was present, despite past studies showing both TcI and TcIV in vectors of the region. Eight of 19 (42.1%) seropositive cats exhibited lymphoplasmacytic inflammation, sometimes with fibrosis, in cardiac tissue compared to 28.6% of 28 seronegative cats (P = 0.10). Domestic cats are affected hosts in the eco-epidemiology of Chagas disease. Future prospective studies are needed to understand disease progression. Veterinarians in the southern United States should consider T. cruzi in their index of suspicion in cats with exposure to vectors and undetermined cardiac abnormalities.


Assuntos
Doenças do Gato/epidemiologia , Doença de Chagas/veterinária , Miocárdio/patologia , Animais , Doenças do Gato/parasitologia , Gatos , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Coração/parasitologia , Imunoensaio/veterinária , Masculino , Prevalência , Texas/epidemiologia
8.
Exp Parasitol ; 210: 107834, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31978394

RESUMO

Studies suggest that the dose of the standard benznidazole (BNZ) treatment regimen might be too high. We investigated the efficacy of BNZ 20 and 40 mg/kg/day compared with standard dose (100 mg/kg/day) to induce cure in mice infected with Trypanosoma cruzi Y strain in the acute and chronic phases of Chagas' disease. Our findings indicate that an experimental treatment with a BNZ low-dose (40 mg/kg/day) is similarly effective as the usual dose in the chronic mice model (100% of cure). In addition, the treatment in the chronic model of Chagas' disease presented better results than the acute model and colon appears to be a key tissue when it comes to evaluating treatment efficacy compared to blood and heart. Therefore, our data suggest the reconsideration of the current therapy, mainly in the chronic phase of the disease.


Assuntos
Doença de Chagas/tratamento farmacológico , Nitroimidazóis/administração & dosagem , Tripanossomicidas/administração & dosagem , Doença Aguda , Animais , Sangue/parasitologia , Doença de Chagas/parasitologia , Doença Crônica , Colo/parasitologia , Ciclofosfamida/administração & dosagem , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Feminino , Coração/parasitologia , Imunossupressão , Camundongos , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/parasitologia , Nitroimidazóis/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/genética , Trypanosoma cruzi/fisiologia
9.
Radiology ; 294(2): 478-481, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31961783

RESUMO

HistoryA 47-year-old Sudanese man without a known remarkable medical history presented to the emergency department for a syncopal episode. The patient denied chest pain, dyspnea, focal weakness, or prior similar episodes. He was originally from north Sudan and eventually moved to Saudi Arabia, where he worked as a farm manager before emigrating to the United States years ago. Physical examination findings and routine laboratory values, including complete blood count and basic metabolic panels, were normal. Electrocardiography revealed nonspecific T-wave inversions, and a series of cardiac biomarkers were negative. A contrast material-enhanced CT angiography pulmonary embolism protocol and cardiac MRI were performed for further evaluation.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Equinococose/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Cardiopatias/patologia , Imagem por Ressonância Magnética/métodos , Animais , Procedimentos Cirúrgicos Cardíacos , Meios de Contraste , Diagnóstico Diferencial , Equinococose/cirurgia , Echinococcus , Eletrocardiografia/métodos , Coração/diagnóstico por imagem , Coração/parasitologia , Cardiopatias/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica
10.
Biochim Biophys Acta Mol Basis Dis ; 1866(3): 165592, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678157

RESUMO

Damaged cells release the pro-inflammatory signal ATP, which is degraded by the ectonucleotidases CD39 and CD73 to the anti-inflammatory mediator adenosine (ADO). The balance between ATP/ADO is known to determine the outcome of inflammation/infection. However, modulation of the local immune response in different tissues due to changes in the balance of purinergic metabolites has yet to be investigated. Here, we explored the contribution of CD73-derived ADO on the acute immune response against Trypanosoma cruzi parasite, which invades and proliferates within different target tissues. Deficiency of CD73 activity led to an enhanced cardiac microbicidal immune response with an augmented frequency of macrophages with inflammatory phenotype and increased CD8+ T cell effector functions. The increment of local inducible nitric oxide (NO) synthase (iNOS)+ macrophages and the consequent rise of myocardial NO production in association with reduced ADO levels induced protection against T. cruzi infection as observed by the diminished cardiac parasite burden compared to their wild-type (WT) counterpart. Unexpectedly, parasitemia was substantially raised in CD73KO mice in comparison with WT mice, suggesting the existence of tissue reservoir/s outside myocardium. Indeed, CD73KO liver and visceral adipose tissue (VAT) showed increased parasite burden associated with a reduced ATP/ADO ratio and the lack of substantial microbicidal immune response. These data reveal that the purinergic system has a tissue-dependent impact on the host immune response against T. cruzi infection.


Assuntos
5'-Nucleotidase/imunologia , Tecido Adiposo/imunologia , Doença de Chagas/imunologia , Miocárdio/imunologia , Trypanosoma cruzi/imunologia , Trifosfato de Adenosina/imunologia , Tecido Adiposo/parasitologia , Animais , Linfócitos T CD8-Positivos/imunologia , Carotenoides/imunologia , Doença de Chagas/parasitologia , Modelos Animais de Doenças , Feminino , Coração/parasitologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/imunologia , Óxido Nítrico Sintase Tipo II/imunologia , Oxigenases/imunologia
11.
Turkiye Parazitol Derg ; 43(4): 182-186, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31865653

RESUMO

Objective: Sarcocystosis is an important zoonotic protozoal disease with worldwide distribution and wide range of hosts. The aim of the present study was to determine the intensity of Sarcocystis spp. infection and to show histopathological features of their cystic lesions in slaughtered cattle of Zabol- Iran. Methods: From April to September 2018, 500 tissue samples from esophagus, heart, diaphragm, tongue and masticatory muscles were prepared from 100 slaughtered cattle. All samples were fixed in 10% neutral buffered formalin and routine tissue processing protocol was performed. Results: The microscopic results showed that 92.2% of specimens had thin-walled cysts of S. cruzi and 14% had thick-walled Sarcocystis (S. hirsuta and S. hominis) but macrocyst was only observed in one cattle. The positivity rate of thin walled cysts was 58.8% for heart, 13.9% for masticatory muscles, 10.2% for tongue, 9.3% for esophagus and 7.8% for diaphragm. The positivity rate of thick walled cysts was 32.8% for esophagus, 28.6% for tongue, 22.9% for heart, 15.7% for masticatory muscles and 0% for diaphragm, which could represent either S. hominis or S. hirsuta. The most infected tissue was heart and the least infected tissue was diaphragm. Thin walled cysts (S. cruzi) were mostly found in heart and were less found in diaphragm. However, thick-walled cysts (S. hirsuta and S. hominis) were mostly detected in esophagus. No thick-walled cysts were found in diaphragm muscle. Conclusion: A high positivity rate of sarcocystosis in slaughtered cattle in Zabol abattoir revealed heavily environmental contamination of Sistan region by this important parasitic disease.


Assuntos
Doenças dos Bovinos/parasitologia , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Zoonoses/parasitologia , Matadouros , Animais , Bovinos , Doenças dos Bovinos/patologia , Diafragma/parasitologia , Esôfago/parasitologia , Coração/parasitologia , Irã (Geográfico) , Músculo Masseter/parasitologia , Sarcocystis/classificação , Sarcocystis/ultraestrutura , Sarcocistose/parasitologia , Sarcocistose/patologia , Língua/parasitologia , Zoonoses/patologia
12.
Parasit Vectors ; 12(1): 586, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842955

RESUMO

BACKGROUND: Foodborne toxoplasmosis in humans can be due to the exposure to tissue cysts of Toxoplasma gondii through the consumption of meat, including pork, of infected animals. Traditional Romanian food habits include pork as the preferred meat, while backyard pig rearing remains a common practice in many rural areas of Romania. The aims of the present study were to estimate the prevalence of T. gondii infection in naturally infected backyard pigs slaughtered for familial consumption and to genetically characterize the T. gondii strains obtained. METHODS: Paired blood and heart samples were collected from 94 backyard pigs, home slaughtered for private consumption. Serum samples were analyzed using the immunofluorescence antibody test (IFAT) for anti-T. gondii antibody detection. Heart samples were screened by polymerase chain reaction (PCR) targeting the 529-bp repeat region (REP529) for T. gondii detection. In addition, heart samples from IFAT positive animals were bioassayed in mice. The T. gondii isolates were genotyped by the analysis of 15 microsatellite markers. RESULTS: The results showed that almost half of the pigs investigated were T. gondii seropositive (46.8%, 95% confidence interval (CI): 36.4-57.4%) and in more than a quarter of the pigs (26.6%, 95% CI: 18.0-36.7%), the parasite was detected by PCR. Three (3/44) T. gondii strains were isolated from hearts of seropositive pigs and they all belonged to genotype II. CONCLUSIONS: The present study showed the presence of T. gondii infection in backyard pigs in Romania, which suggests that consumption of pork from animals reared and slaughtered at home may pose a potential threat to human health and should be given attention. In addition, to our knowledge, this is the first study to provide data concerning T. gondii strains circulating in pigs from Romania.


Assuntos
Doenças dos Suínos/epidemiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Bioensaio , Sangue/parasitologia , Técnica Direta de Fluorescência para Anticorpo , Coração/parasitologia , Camundongos , Reação em Cadeia da Polimerase , Prevalência , Romênia/epidemiologia , Suínos
13.
Vet Parasitol ; 276: 108956, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706235

RESUMO

Turkeys and chickens were orally infected with tissue cysts (one mouse brain) or oocysts (103, 105 or 106 oocysts) of three T. gondii strains of the clonal types II and III (ME49, CZ-Tiger, NED) to investigate the influence of the applied T. gondii strain and infective doses on the distribution of T. gondii in several organs and tissues and the serologic response of chickens and turkeys. Organ samples from 16 different tissues, including heart, brain, muscles and gizzard were analyzed by PCR. Brain and heart were found most frequently positive for T. gondii DNA in both species, followed by gizzard. Serological analysis with kinetic ELISA for turkey samples and IFAT for chicken samples were performed once a week. In both species a dose-depending serological response was found. Turkeys seroconverted one week after infection with CZ-Tiger strain and medium and high doses of ME49 oocysts. In chickens, infection with medium and high doses of CZ-Tiger led to seroconversion one week p.i. Frequency of T. gondii positive organs showed a trend of a dose-effect in both species after infection with the type II strains. The NED strain showed low virulence in chickens and turkeys, demonstrated by clearly less T. gondii positive organs. Infection with tissue cysts of all three strains revealed T. gondii stages in tissues of turkeys and chickens. In conclusion, our data show a risk for human infection with T. gondii due to consumption of chicken and turkey meat.


Assuntos
Galinhas/parasitologia , Modelos Animais de Doenças , Doenças das Aves Domésticas/parasitologia , Toxoplasmose Animal/parasitologia , Perus/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/parasitologia , Gatos , DNA de Protozoário/análise , Relação Dose-Resposta Imunológica , Moela das Aves/parasitologia , Coração/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Músculos/parasitologia , Organismos Livres de Patógenos Específicos , Toxoplasma/genética , Toxoplasma/imunologia
14.
J Parasitol ; 105(6): 890-892, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31738124

RESUMO

Toxoplasma gondii infections are prevalent in most warm-blooded animals worldwide. During the 2018 November hunting season in Pennsylvania, fresh (unfixed, not frozen) samples obtained from 99 harvested elk (Cervus canadensis) were tested for T. gondii infection. Antibodies to T. gondii were detected in 69 of 99 (69.7%) elk tested by the modified agglutination test (MAT, 1:25 cut-off). Tongues and hearts from 16 elk with high MAT titers (>1:200) were bioassayed for T. gondii by inoculation in outbred Swiss Webster (SW) and interferon-gamma gene knockout (KO) mice. Viable T. gondii was isolated from tongues of 2 elk with MAT titers of 1:200 and 1:3,200. Toxoplasma gondii from both isolates were successfully propagated in cell culture. Genetic typing on DNA extracted from culture-derived tachyzoites using the PCR restriction fragment length polymorphism with 10 genetic markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) revealed that both isolates belonged to ToxoDB PCR-RFLP genotype #5 that is widely prevalent in wildlife in the United States. Our results suggest that elk may clear T. gondii organisms from their tissues.


Assuntos
Cervos/parasitologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio/veterinária , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Feminino , Técnicas de Genotipagem/veterinária , Coração/parasitologia , Masculino , Camundongos , Camundongos Knockout , Pennsylvania/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Estudos Soroepidemiológicos , Língua/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Toxoplasmose Animal/transmissão
15.
Ann Parasitol ; 65(3): 225-236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31578846

RESUMO

Hydatidosis or echinococcosis is considered to be one of the most common zoonotic diseases of the animals. Infection occurs when intermediate hosts such as camel, cattle, sheep, and goats ingested food or water contaminated with eggs from the definitive host (dog). This is a cross-sectional study which was carried out in one of the biggest abattoirs in Makkah in the west of Saudi Arabia. A total number of 38302 goats were examined and recorded at Makkah abattoirs. The examination had been performed to all slaughtered animals on two organs (spleen and heart) for detection of any hydatid cysts during the period from July 2018 until December 2018. The study included also histopathological tissue evaluation. The total infections number of hydatidosis in goats is 0.23%. The infected hearts were 40.35% whereas the infected spleen was 48.48% subsequently in local animals. The imported animals were 2124, the infected animals in heart were 59.64%, whereas the infected animal involving spleen were 51.51%. Meanwhile, results of histopathological examination had shown that most of the hydatid cysts in goats caused progressive focal pressure and degenerative changes in the surrounding tissue.


Assuntos
Equinococose , Doenças das Cabras , Coração , Baço , Animais , Estudos Transversais , Equinococose/veterinária , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cabras , Coração/parasitologia , Prevalência , Arábia Saudita , Baço/parasitologia
16.
Biomedica ; 39(Supl. 2): 32-43, 2019 08 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31529832

RESUMO

Introduction: Trypanosoma cruzi is the causal agent of the American trypanosomiasis, an endemic disease in México. The commensal rodents Mus musculus and Rattus rattus are reservoirs of this parasite, which invades cardiac fibers and develops parasite nests causing various lesions. Histopathological studies in naturally infected rodents are scarce. Objective: To describe the types and frequencies of microscopic lesions in cardiac tissue of M. musculus and R. rattus infected with T. cruzi captured in Mérida, México. Materials and methods: The rodents were captured in suburban environments of Mérida. Cardiac tissue was extracted and processed by the paraffin inclusion technique and hematoxylin and eosin stained. The observation was made with a conventional microscope and all the lesions, as well as their degree, were identified. Results: Eight tissue samples of M. musculus and seven of R. rattus were studied. Parasite nests were found in 7/15, specifically 3/8 in M. musculus and 4/7 in R. rattus. The inflammatory infiltrate was the most frequent lesion. Other lesions were: Degeneration of cardiac fibers (8/15), congestion of blood vessels (6/15), and necrosis (5/15). Discussion: The lesions we observed have been described in experimental animal models and in humans with American trypanosomiasis. The inflammatory infiltrate has been identified as the most significant lesion in humans and reservoirs in the chronic stage of the disease. Conclusion: The lesions we described are associated with T. cruzi infection, which confirms that the rodents studied are reservoirs of this parasite.


Assuntos
Cardiomiopatia Chagásica/veterinária , Doença de Chagas/epidemiologia , Reservatórios de Doenças/parasitologia , Coração/parasitologia , Camundongos/parasitologia , Ratos/parasitologia , Doenças dos Roedores/parasitologia , Trypanosoma cruzi/isolamento & purificação , Animais , Animais Selvagens/parasitologia , Cardiomiopatia Chagásica/epidemiologia , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/patologia , Doença de Chagas/transmissão , Doenças Endêmicas/veterinária , Feminino , Masculino , México/epidemiologia , Doenças dos Roedores/epidemiologia , Saúde Suburbana
17.
Comp Immunol Microbiol Infect Dis ; 67: 101347, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546127

RESUMO

This study aimed to genetically characterize and to determine virulence from Toxoplasma gondii samples from invasive animals in the Island of Fernando de Noronha, Brazil. Blood samples were collected from 21 tegu-lizard (Salvator merianae), 12 rock-cavies (Kerodon rupestris) and 154 black-rats (Rattus rattus) from the Island and MAT (cutoff 1:25) detected anti-T. gondii antibodies in 0% of the tegus (0/21); 58.3% of the rock-cavies (7/12) and 22.7% of rats (35/154). Tissue samples (brain, heart, liver and lung) from positive animals in MAT were collected for molecular analysis and for bioassay in Swiss Webster mice. After observation period, mice were euthanized, and serological detection and tissue cyst search in the brain were performed. The brain of positive animals for serological detection or tissue cyst search was cultured in MARC-145 cells for maintenance of the T. gondii isolate. No isolate was obtained from rock cavies. Nine isolates were obtained by bioassay of 35 seropositive black rats. DNA samples were extracted from rat tissues and from parasite isolates in cell culture, and genotyped using 10 PCR-RFLP markers. ToxoDB genotypes #78 (1) from rat tissue and #146 (4), #163 (2), #260 (2) and #291 (1) from cell culture were detected. Markers of genes ROP18 and ROP5 were analyzed and in vivo virulence test was conducted in mice. Analysis revealed two allele combinations, 3/1 and 3/3, indicating non-lethal T. gondii strains, which is supported by mouse virulence test.


Assuntos
Anticorpos Antiprotozoários/sangue , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Encéfalo/parasitologia , Brasil/epidemiologia , Linhagem Celular , DNA de Protozoário/genética , Variação Genética/genética , Genótipo , Coração/parasitologia , Fígado/parasitologia , Lagartos/parasitologia , Pulmão/parasitologia , Camundongos , Ratos , Toxoplasma/isolamento & purificação
18.
PLoS Negl Trop Dis ; 13(9): e0007226, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31536489

RESUMO

Chagas disease, caused by Trypanosoma cruzi, is a neglected tropical disease that affects 5-6 million people in endemic areas of the Americas. Presently, chemotherapy relies on two compounds that were proposed as trypanocidal drugs four decades ago: nifurtimox and benznidazole. Both drugs are able to eliminate parasitemia and to avoid seroconversion in infected people when used in the acute phase; however, their use in the chronic phase (the time when the majority of cases are diagnosed) is limited due to their serious side effects. Memantine is a glutamate receptor antagonist in the central nervous system of mammals that has been used for the treatment of Alzheimer's disease. Our group previously reported memantine as a trypanocidal drug that is able to induce apoptosis-like death in T. cruzi. In the present work, we further investigated the effects of memantine on the infection of RAW 264.7 macrophages and in vivo (in BALB/c mice). Here, we showed that memantine is able to diminish NO and Ca2+ entry in both LPS-activated and non-activated cells. These results, together with the fact that memantine was also able to reduce the infection of macrophages, led us to propose that this drug is able to activate a pro-oxidant non-NO-dependent cell defense mechanism. Finally, infected mice that were treated with memantine had diminished parasitemia, cardiac parasitic load, and inflammatory infiltrates. In addition, the treated mice had an increased survival rate. Taken together, these results indicate memantine to be a candidate drug for the treatment of Chagas disease.


Assuntos
Doença de Chagas/tratamento farmacológico , Memantina/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Cálcio/metabolismo , Doença de Chagas/parasitologia , Feminino , Coração/parasitologia , Lipopolissacarídeos/farmacologia , Macrófagos/parasitologia , Memantina/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Óxidos de Nitrogênio/metabolismo , Carga Parasitária , Parasitemia , Células RAW 264.7 , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Tripanossomicidas/administração & dosagem
20.
PLoS Negl Trop Dis ; 13(7): e0007602, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31365537

RESUMO

TGF-ß involvement in Chagas disease cardiomyopathy has been clearly demonstrated. The TGF-ß signaling pathway is activated in the cardiac tissue of chronic phase patients and is associated with an increase in extracellular matrix protein expression. The aim of this study was to investigate the effect of GW788388, a selective inhibitor of TßR1/ALK5, on cardiac function in an experimental model of chronic Chagas' heart disease. To this end, C57BL/6 mice were infected with Trypanosoma cruzi (102 parasites from the Colombian strain) and treated orally with 3mg/kg GW788388 starting at 120 days post-infection (dpi), when 100% of the infected mice show cardiac damage, and following three distinct treatment schedules: i) single dose; ii) one dose per week; or iii) three doses per week during 30 days. The treatment with GW788388 improved several cardiac parameters: reduced the prolonged PR and QTc intervals, increased heart rate, and reversed sinus arrhythmia, and atrial and atrioventricular conduction disorders. At 180 dpi, 30 days after treatment interruption, the GW3x-treated group remained in a better cardiac functional condition. Further, GW788388 treatment reversed the loss of connexin-43 enriched intercellular plaques and reduced fibrosis of the cardiac tissue. Inhibition of the TGF-ß signaling pathway reduced TGF-ß/pSmad2/3, increased MMP-9 and Sca-1, reduced TIMP-1/TIMP-2/TIMP-4, and partially restored GATA-6 and Tbox-5 transcription, supporting cardiac recovery. Moreover, GW788388 administration did not modify cardiac parasite load during the infection but reduced the migration of CD3+ cells to the heart tissue. Altogether, our data suggested that the single dose schedule was not as effective as the others and treatment three times per week during 30 days seems to be the most effective strategy. The therapeutic effects of GW788388 are promising and suggest a new possibility to treat cardiac fibrosis in the chronic phase of Chagas' heart disease by TGF-ß inhibitors.


Assuntos
Benzamidas/uso terapêutico , Cardiomiopatia Chagásica/tratamento farmacológico , Coração/efeitos dos fármacos , Pirazóis/uso terapêutico , Fator de Crescimento Transformador beta/antagonistas & inibidores , Tripanossomicidas/uso terapêutico , Animais , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/patologia , Doença Crônica , Conexina 43/metabolismo , Modelos Animais de Doenças , Feminino , Fibrose/tratamento farmacológico , Coração/parasitologia , Sistema de Condução Cardíaco/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Carga Parasitária , Trypanosoma cruzi/efeitos dos fármacos
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