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1.
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
2.
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
3.
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
4.
Res Vet Sci ; 126: 51-58, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31437776

RESUMO

Cardiopulmonary nematodes are among the most pathogenic parasites of domestic and wild canids. The aim of this study was to describe the species diversity, prevalence and infection intensity of these parasites in the Iberian wolf (Canis lupus signatus) and the red fox (Vulpes vulpes) in the northwest of the Iberian Peninsula. 257 foxes and 74 wolves were necropsied between 2008 and 2014. Four nematode species were identified: Angiostrongylus vasorum, Eucoleus aerophilus, Crenosoma vulpis and Filaroides hirthi. This last species was only found in wolves, being the first time that is cited worldwide in this wild canid. The overall parasite prevalence was significantly higher in foxes (70%) than in wolves (28%). Specifically, prevalences in foxes and wolves were, respectively, 43% and 22% for A. vasorum, 33% and 5% for E. aerophilus, and 30% and 9% for C. vulpis. The prevalence of F. hirthi was 16%. The A. vasorum intensity was significantly higher in foxes than in wolves. Differences between host species in the risk of infection would be associated to diverging feeding behavior, and possibly reflects a parasite-host adaptation related to host's hunting strategies and cardiorespiratory requirements. This study revealed an association between infection and environmental factors, and highlighted a wide variation in the spatial distribution of A. vasorum. Our results indicate that cardiopulmonary parasites are widespread in wild canids in northwest Spain, and further agrees with other studies indicating the expansion of A. vasorum in Europe and, therefore, the urgent need to investigate infection in dogs in sympatric areas.


Assuntos
Raposas/parasitologia , Cardiopatias/veterinária , Pneumopatias Parasitárias/veterinária , Infecções por Nematoides/veterinária , Lobos/parasitologia , Angiostrongylus , Animais , Animais Selvagens , Coração/parasitologia , Cardiopatias/epidemiologia , Cardiopatias/parasitologia , Pneumopatias Parasitárias/epidemiologia , Pneumopatias Parasitárias/parasitologia , Metastrongyloidea , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Prevalência , Espanha/epidemiologia
5.
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
6.
Exp Parasitol ; 205: 107714, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31279927

RESUMO

The objective of the present study was to evaluate the clinical signs, electrocardiographic signs and evolution of histopathological lesions in the heart of sheep experimentally infected by Trypanosoma vivax during the acute and chronic phases of infection as well as to investigate the presence of parasitic DNA in the heart using polymerase chain reaction (PCR). Twenty-two male sheep were divided into the following four groups: G1, which consisted of six sheep infected by T. vivax that were evaluated until 20 days post-infection (dpi; acute phase); G2, which consisted of six sheep infected by T. vivax that were evaluated until 90 dpi (chronic phase); and G3 and G4 groups, which each consisted of five uninfected sheep. At the end of the experimental period, electrocardiographic evaluations and necroscopic examinations were performed. Fragments of the heart were collected and stained by Hematoxylin-Eosin and Masson's trichrome, and the fragments were also evaluated by PCR for T. vivax. G2 animals presented clinical signs suggestive of heart failure and electrocardiogram alterations characterized by prolonged P, T and QRS complex durations as well as by a cardiac electrical axis shift to the left and increased heart rate. In these animals, mononuclear multifocal myocarditis and interstitial fibrosis were also observed. PCR revealed positivity for T. vivax in two G1 animals and in all G2 animals. Thus, these findings suggested that T. vivax is responsible for the occurrence of cardiac lesions, which are related to heart failure, electrocardiographic alterations and mortality of the infected animals.


Assuntos
DNA de Protozoário/isolamento & purificação , Insuficiência Cardíaca/veterinária , Coração/parasitologia , Doenças dos Ovinos/parasitologia , Trypanosoma vivax/patogenicidade , Tripanossomíase Africana/veterinária , Doença Aguda , Animais , Anticorpos Antiprotozoários/sangue , Doença Crônica/veterinária , Eletrocardiografia/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/parasitologia , Imunoglobulina G/sangue , Masculino , Miocárdio/patologia , Parasitemia/veterinária , Pericardite/parasitologia , Pericardite/patologia , Pericardite/veterinária , Reação em Cadeia da Polimerase/veterinária , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/mortalidade , Doenças dos Ovinos/patologia , Trypanosoma vivax/genética , Trypanosoma vivax/imunologia , Trypanosoma vivax/isolamento & purificação , Tripanossomíase Africana/complicações , Tripanossomíase Africana/mortalidade , Tripanossomíase Africana/patologia
7.
PLoS Negl Trop Dis ; 13(7): e0007597, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356587

RESUMO

CD8+ T lymphocytes play an important role in controlling infections by intracellular pathogens. Chemokines and their receptors are crucial for the migration of CD8+ T-lymphocytes, which are the main IFNγ producers and cytotoxic effectors cells. Although the participation of chemokine ligands and receptors has been largely explored in viral infection, much less is known in infection by Trypanosoma cruzi, the causative agent of Chagas disease. After T. cruzi infection, CXCR3 chemokine receptor is highly expressed on the surface of CD8+ T-lymphocytes. Here, we hypothesized that CXCR3 is a key molecule for migration of parasite-specific CD8+ T-cells towards infected tissues, where they may play their effector activities. Using a model of induction of resistance to highly susceptible A/Sn mice using an ASP2-carrying DNA/adenovirus prime-boost strategy, we showed that CXCR3 expression was upregulated on CD8+ T-cells, which selectively migrated towards its ligands CXCL9 and CXCL10. Anti-CXCR3 administration reversed the vaccine-induced resistance to T. cruzi infection in a way associated with hampered cytotoxic activity and increased proapoptotic markers on the H2KK-restricted TEWETGQI-specific CD8+ T-cells. Furthermore, CXCR3 receptor critically guided TEWETGQI-specific effector CD8+ T-cells to the infected heart tissue that express CXCL9 and CXCL10. Overall, our study pointed CXCR3 and its ligands as key molecules to drive T. cruzi-specific effector CD8+ T-cells into the infected heart tissue. The unveiling of the process driving cell migration and colonization of infected tissues by pathogen-specific effector T-cells is a crucial requirement to the development of vaccine strategies.


Assuntos
Vacinas contra Adenovirus/imunologia , Linfócitos T CD8-Positivos/imunologia , Cardiomiopatia Chagásica/imunologia , Quimiotaxia de Leucócito , Miocárdio/metabolismo , Receptores CXCR3/metabolismo , Trypanosoma cruzi/imunologia , Animais , Apoptose , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/prevenção & controle , Feminino , Coração/parasitologia , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/imunologia , Receptores CCR2/metabolismo , Baço/imunologia , Regulação para Cima , Vacinas de DNA/imunologia
8.
Parasite ; 26: 36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31198175

RESUMO

Currently, information on the occurrence and genetic characterization of Toxoplasma gondii and Neospora caninum in tissues of rabbits in China is lacking. In this study, brain and heart samples from 470 slaughtered domestic rabbits were collected in Henan Province, Central China. The occurrence rate of T. gondii and N. caninum DNA detected by nested PCR was 2.8% and 2.1%, respectively. There were no significant differences (p > 0.05) in the frequency of the two parasite infections in relation to sex, breed, and region. Three out of 13 T. gondii-positive samples were completely or partially genotyped at 11 genetic markers using PCR-RFLP, and one was identified as ToxoDB genotype #9. For N. caninum, three different sequences at the ITS1 region and two genotypes at the MS5 microsatellite locus were identified. To our knowledge, this is the first genetic characterization of N. caninum isolates from rabbits.


Assuntos
Animais Domésticos/parasitologia , Coccidiose/veterinária , Carne/parasitologia , Neospora/genética , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Animais , Encéfalo/parasitologia , China/epidemiologia , Coccidiose/epidemiologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Feminino , Genótipo , Coração/parasitologia , Masculino , Repetições de Microssatélites , Neospora/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Coelhos/parasitologia , Toxoplasma/isolamento & purificação
9.
Exp Parasitol ; 204: 107711, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31254494

RESUMO

Chagas disease (CD) is a serious public health problem in Latin America and its treatment remains neglected. Benznidazole (BZ), the only drug available in Brazil, presents serious side effects and low therapeutic efficacy, especially at the chronic phase. The last clinical trials demonstrated that the first generation of azole compounds were less successful than BZ in CD chemotherapy, which stimulated studies of these compounds associated to BZ and nifurtimox (NF). This study evaluated the therapeutic efficacy of BZ, itraconazole (ITZ) and their combination (BZ + ITZ) in dogs infected with the VL-10 T. cruzi strain in the acute phase of the disease. Twenty young mongrel dogs were inoculated with 2.0 × 103 blood trypomastigotes/kg and divided into four groups: treated with BZ, ITZ and BZ + ITZ for 60 days, and control group (INT). The parasitemia of the BZ + ITZ and BZ groups were similar and showed significant reduction compared to the INT group. The group treated with ITZ also showed significant parasitemia reduction compared to the INT group. The global analysis of hemoculture (HC), blood PCR, conventional serology (CS-ELISA), heart qPCR and histopathology techniques, used in the post-treatment evaluation, revealed that BZ + ITZ combination lead to a more reduction of parasitemia during the acute phase and heart qPCR positivity, less cardiac damage (inflammation and fibrosis in the left ventricle) and total survival. According to the classical cure criteria one animal treated with BZ + ITZ can be considered cured in its final evaluation and two other dogs, one of this group and one treated with ITZ were in process of cure. At least for BZ-resistant T. cruzi strains such as VL-10, BZ + ITZ was not effective to induce parasitological cure or a profound and sustained reduction of the parasite burden in blood and infected organs.


Assuntos
Doença de Chagas/tratamento farmacológico , Itraconazol/uso terapêutico , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico , Doença Aguda , Animais , Doença de Chagas/sangue , DNA de Protozoário/isolamento & purificação , Cães , Quimioterapia Combinada , Ensaio de Imunoadsorção Enzimática , Feminino , Coração/parasitologia , Humanos , Masculino , Miocárdio/química , Miocárdio/patologia , Parasitemia/sangue , Parasitemia/tratamento farmacológico , Reação em Cadeia da Polimerase , Distribuição Aleatória
10.
Turkiye Parazitol Derg ; 43(2): 92-95, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31204464

RESUMO

During the routine postmortem inspection from carcasses and offal of slaughtered ewes in an abattoir in Isfahan (Iran), an ovine heart was discovered with a firm nodule in the myocard on palpation. In closer examination, a liquid containing cyst (1x1 cm) was recognized on left part of the heart. The cyst had thick fibrotic capsule in outer surface and a thin inner layer containing few white clusters of scolices. White clusters contained scolices that adhered to the inner transparent layer, like white beads. Based on the gross and microscopical characteristics, the cyst was diagnosed as non-cerebral coenurus cyst. This is a rare report of heart coenurosis in a sheep.


Assuntos
Cestoides/isolamento & purificação , Infecções por Cestoides/veterinária , Coração/parasitologia , Doenças dos Ovinos/diagnóstico , Matadouros , Animais , Autopsia/veterinária , Cestoides/anatomia & histologia , Cestoides/classificação , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/patologia , Feminino , Miocárdio/patologia , Ovinos , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/patologia
11.
J Parasitol ; 105(3): 391-394, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31059382

RESUMO

Toxoplasmosis in wild turkeys (Meleagris gallopavo) is of epidemiological interest because turkeys feed from the ground, and detection of infection in turkeys indicates contamination by oocysts in the environment. During the 2018 spring hunting season in Pennsylvania, fresh (unfixed, not frozen) samples were obtained from 20 harvested wild turkeys and tested for Toxoplasma gondii infection. Hearts from all wild turkeys and skeletal muscle from 1 were bioassayed for T. gondii by inoculation in outbred Swiss Webster (SW) and interferon-gamma gene knockout (KO) mice. Antibodies to T. gondii were detected in 1:5 dilution of neat serum from 5 of 15 wild turkeys and in fluid from the heart of 1 of 4 wild turkeys with the modified agglutination test (MAT); neat serum was not available from 4 wild turkeys. Viable T. gondii was isolated from hearts of 5 wild turkeys, 1 with MAT of 1:10, 1 with MAT of 1:5, and 3 seronegative (MAT < 1:5). Toxoplasma gondii was isolated from both heart and skeletal muscle in the 1 wild turkey that had skeletal muscle submitted. The KO mice inoculated with tissue from all 5 infected wild turkeys died or were euthanatized when ill, 7-21 days post-inoculation (PI). Tachyzoites were detected in lungs of all KO mice, and the T. gondii strains were successfully propagated in cell culture. The SW mice inoculated with tissues of wild turkeys remained asymptomatic, and tissue cysts were seen in the brains of infected mice when euthanatized in good health at 46 days PI; 1 of the 2 SW mice inoculated with the heart of 1 turkey died on day 26, and tachyzoites were detected in its lung. 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 4 isolates belonged to ToxoDB PCR-RFLP genotype #5 and 1 was genotype #216.


Assuntos
Doenças das Aves/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Perus/parasitologia , Testes de Aglutinação/veterinária , Animais , Animais Selvagens , Anticorpos Antiprotozoários/sangue , Doenças Assintomáticas , Doenças das Aves/epidemiologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Técnicas de Genotipagem/veterinária , Coração/parasitologia , Camundongos , Camundongos Knockout , Músculo Esquelético/parasitologia , Pennsylvania/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia
12.
Vet Parasitol ; 269: 2-6, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31079823

RESUMO

Neospora caninum is an apicomplexan protozoan parasite that is a leading cause of abortion in cattle. Detection of parasite-specific DNA by PCR is a highly sensitive method for identifying the presence of N. caninum in a variety of tissues. We developed and validated a probe-based real-time PCR assay targeting the conserved Nc5 gene of N. caninum. Using N. caninum strain Nc-1 genomic DNA and a synthetic gene fragment as amplification standards, we determined the PCR amplification efficiency and the limit of detection to be 95.60% and 3 copies, respectively. Five pathogens frequently associated with bovine abortions, namely bovine viral diarrhea virus types I and II, bovine alphaherpesvirus-1, Chlamydia, and Leptospira, were tested to ensure analytical exclusivity. A total of 103 clinical samples from aborted fetuses were tested concurrently with a standard conventional PCR and the new probe-based real-time PCR assay. All tested samples showed 100% agreement between these two assays. In conclusion, the probe-based real-time PCR assay facilitates accurate and rapid detection of N. caninum from abortions in cattle.


Assuntos
Aborto Animal/diagnóstico , Doenças dos Bovinos/diagnóstico , Coccidiose/veterinária , Neospora/isolamento & purificação , Complicações Parasitárias na Gravidez/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Feto Abortado/parasitologia , Aborto Animal/parasitologia , Animais , Encéfalo/parasitologia , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/diagnóstico , Coccidiose/parasitologia , Primers do DNA/genética , Sondas de DNA/genética , Feminino , Coração/parasitologia , Neospora/genética , Gravidez , Complicações Parasitárias na Gravidez/diagnóstico , Complicações Parasitárias na Gravidez/parasitologia
13.
Malar J ; 18(1): 174, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113429

RESUMO

BACKGROUND: Avian malaria parasites (genus Plasmodium) are cosmopolitan and some species cause severe pathologies or even mortality in birds, yet their virulence remains fragmentally investigated. Understanding mechanisms and patterns of virulence during avian Plasmodium infections is crucial as these pathogens can severely affect bird populations in the wild and cause mortality in captive individuals. The goal of this study was to investigate the pathologies caused by the recently discovered malaria parasite Plasmodium homocircumflexum (lineage pCOLL4) in four species of European passeriform birds. METHODS: One cryopreserved P. homocircumflexum strain was multiplied and used for experimental infections. House sparrows (Passer domesticus), common chaffinches (Fringilla coelebs), common crossbills (Loxia curvirostra) and common starlings (Sturnus vulgaris) were exposed by subinoculation of infected blood. Experimental and control groups (8 individuals in each) were observed for over 1 month. Parasitaemia, haematocrit value and body mass were monitored. At the end of the experiment, samples of internal organs were collected and examined using histological and chromogenic in situ hybridization methods. RESULTS: All exposed birds were susceptible, with similar average prepatent period and maximum parasitaemia, yet virulence was different in different bird species. Mortality due to malaria was reported in chaffinches, house sparrows and crossbills (7, 5 and 3 individuals died respectively), but not in starlings. Exoerythrocytic meronts (phanerozoites) were observed in the brain of all dead experimental birds. Blockage of blood vessels in the brain led to cerebral ischaemia, invariably causing brain damage, which is likely the main reason of mortality. Phanerozoites were observed in parenchymal organs, heart and muscles of all infected individuals, except starlings. CONCLUSION: This study shows that P. homocircumflexum is generalist and the same lineage caused similar parasitaemia-related pathologies in different host species. Additionally, the mode of exo-erythrocytic development is different in different birds, resulting in different mortality rates. This should be taken into consideration in studies addressing pathology during avian malaria infections.


Assuntos
Malária Aviária/parasitologia , Passeriformes/parasitologia , Plasmodium/patogenicidade , Animais , Encéfalo/parasitologia , Encéfalo/patologia , Coração/parasitologia , Fígado/parasitologia , Fígado/patologia , Parasitemia , Filogenia , Plasmodium/genética , Reação em Cadeia da Polimerase , Virulência
14.
Exp Parasitol ; 201: 49-56, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31029700

RESUMO

Trypanosoma congolense is an important pathogen that wreaks havoc in the livestock industry of the African continent. This study evaluated the in vivo antitrypanosomal activity of geranylacetone and its ameliorative effect on the disease-induced anaemia and organ damages as well as its inhibitory effects against trypanosomal sialidase using in vitro and in silico techniques. Geranylacetone was used to treat T. congolense infected rats, at a dose of 50 and 100 mg/kg BW, for 14 days where it was found to reduce the parasite burden in the infected animals. Moreover, 100 mg/kg BW of geranylacetone significantly (p < 0.05) ameliorated the anaemia, hepatic and renal damages caused by the parasite. This is in addition to the alleviation of the parasite-induced hepatosplenomegaly and upsurge in free serum sialic acid levels in the infected animals which were associated with the observed anaemia amelioration by the compound. Consequently, bloodstream T. congolense sialidase was partially purified on DEAE cellulose column and inhibition kinetic studies revealed that the enzyme was inhibited by geranylacetone via an uncompetitive inhibition pattern. In silico analysis using molecular docking with Autodock Vina indicated that geranylacetone binds to trypanosomal sialidase with a minimum free binding energy of -5.8 kcal/mol which was mediated by 26 different kinds of non-covalent interactions excluding hydrogen bond whilst Asp163 and Phe421 had the highest number of the interactions. The data suggests that geranylacetone has trypanostatic activity and could protect animals against the T. congolense-induced anaemia through the inhibition of sialidase and/or the protection of the parasite-induced hepatosplenomegaly.


Assuntos
Anemia/prevenção & controle , Terpenos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma congolense/efeitos dos fármacos , Tripanossomíase Africana/tratamento farmacológico , Anemia/tratamento farmacológico , Anemia/parasitologia , Animais , Feminino , Coração/efeitos dos fármacos , Coração/parasitologia , Concentração Inibidora 50 , Rim/efeitos dos fármacos , Rim/parasitologia , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/parasitologia , Fígado/patologia , Masculino , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/parasitologia , Neuraminidase/antagonistas & inibidores , Neuraminidase/química , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Rubiaceae/química , Baço/efeitos dos fármacos , Baço/parasitologia , Baço/patologia , Terpenos/química , Terpenos/uso terapêutico , Tripanossomicidas/química , Tripanossomicidas/uso terapêutico , Trypanosoma congolense/enzimologia , Tripanossomíase Africana/complicações , Tripanossomíase Africana/parasitologia
15.
Vet Parasitol Reg Stud Reports ; 15: 100256, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30929933

RESUMO

The aim of this study was to investigate the occurrence of sarcocysts in sheep slaughtered in the Rio Grande do Sul state, Brazil. Heart and esophagus samples from 130 sheep were subjected to macroscopic and microscopic examination, followed by molecular analysis. Ten sheep (7.7%) had Sarcocystis gigantea macrocysts in esophagus, as identified by gene sequencing. Microcysts were present in 96.1% of the sheep, with a higher frequency (p < .05) in the heart (91.5%) compared to the esophagus (81.5%) samples. The microcysts were identified as Sarcocystis tenella by gene sequencing. Our results revealed a high frequency of Sarcocystis spp. infection in sheep from southern Brazil. To the authors knowledge, this is the first molecular confirmation of S. gigantea presence in Brazil.


Assuntos
Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Ovinos/parasitologia , Animais , Brasil/epidemiologia , DNA de Protozoário/genética , Esôfago/parasitologia , Coração/parasitologia , Sarcocystis/genética , Sarcocistose/epidemiologia , Análise de Sequência de DNA
16.
Vet Parasitol Reg Stud Reports ; 15: 100266, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30929943

RESUMO

Coenurus cerebralis is the larval stage of Taenia multiceps, which infects the muscles and brain of goats and, to a lesser extent, sheep. The resulting cerebral and non-cerebral infections caused by the larval form (metacestode) of this cestode are commonly known as coenurosis. A weak emaciated carcass of five months old female goat, on necropsy, revealed numerous parasitic cysts (n = 56, grossly visible) in the visceral cavity including heart, diaphragm, thoracic cavity, abdominal cavity and pelvic inlet. A large number of variable sized parasitic cysts were also observed embedded in the pericardium and myocardium causing functional damage to the heart. The parasite caused extensive tissue damage at gross and microscopic levels in the heart including traumatic destruction of the myocardium with degenerative and necrotic changes and infiltration of mononuclear cells. On parasitological examination, the cysts were identified as Coenurus cerebralis, as the scolices had characteristic four suckers and a rostellum with a double crown of hooks. Further confirmation was done using polymerase chain reaction targeting specific ND1 and CO1 genes. Phylogenetic analysis of CO1 and ND1 genes showed a major branch comprising two clades of T. multiceps grouped as separate entities with the first clade showing T. multiceps/Coenurus cerebralis native CIRG strain (cerebral) being placed in proximity to T. multiceps/Coenurus cerebralis CIRG strain (non-cerebral/visceral) compared to the Chinese strains of T. multiceps. The phylogenetic analysis of ND1 and CO1 genes of C. cerebralis of cerebral and non-cerebral isolates revealed close proximity but expressed in two different disease forms (i.e., visceral coenurosis and neural coenurosis) which indicated that they were very close divergent from a common ancestor. On the basis of the observations it was concluded that goat died due to cardiac dysfunction resulting from severe systemic infection of metacestode of T. multiceps was closely related to isolate that caused neural coenurosis in another goat. Based on the sequencing analysis and phylogenetic information, the possible differences in the clinical manifestation (neural or visceral) could be attributed to the pathogenesis.


Assuntos
Encéfalo/parasitologia , Infecções por Cestoides/veterinária , Doenças das Cabras/epidemiologia , Coração/parasitologia , Filogenia , Taenia/classificação , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Variação Genética , Doenças das Cabras/parasitologia , Cabras/parasitologia , Índia/epidemiologia , Miocárdio/patologia , Reação em Cadeia da Polimerase , Taenia/patogenicidade
17.
Methods Mol Biol ; 1955: 203-214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30868529

RESUMO

MicroRNAs (miRNAs) are a class of small noncoding RNAs (typically 19-23 nucleotides) which act by annealing to partially complementary binding sites present on the 3' untranslated regions (UTR) of messenger RNAs (mRNAs) leading to inhibition of protein translation or by inducing mRNA decay. Since their discovery, miRNAs have come to be recognized as master regulators of gene expression in plant and mammals, controlling tissue-specific protein expression. Up to one-third of mammalian mRNAs are susceptible to miRNA-mediated regulation. It has been shown that miRNAs are determinants of the physiology and pathophysiology of the cardiovascular system, and altered expression of muscle- and/or cardiac-specific miRNAs in myocardial tissue is involved in heart development and cardiovascular diseases, including myocardial hypertrophy, heart failure, and fibrosis. The analysis of miRNA expression pattern provides important information, as well as is a starting point to understand miRNA function in different tissues, during development, and in disease. Several techniques can be used for miRNA profiling analysis like high-throughput sequencing, microarrays, and real-time PCR using microfluidic low-density arrays. This chapter describes the complete methodology to perform miRNA profiling using the stem-loop reverse-transcription (RT)-based TaqMan® MicroRNA low-density arrays (TLDA) method. This methodology was used to perform miRNA profiling in the heart of T. cruzi acutely infected mice.


Assuntos
Doença de Chagas/genética , Perfilação da Expressão Gênica/métodos , Coração/parasitologia , MicroRNAs/genética , Transcriptoma , Trypanosoma cruzi/fisiologia , Animais , Doença de Chagas/parasitologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Interações Hospedeiro-Parasita , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Trypanosoma cruzi/isolamento & purificação
18.
Methods Mol Biol ; 1955: 381-395, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30868542

RESUMO

Trypanosoma cruzi, the causal agent of chronic Chagas cardiomyopathy, exhibits an important tropism for cardiac tissue. In consequence, T. cruzi experimental infection represents a unique model to study cardiac macrophage behavior and effector functions during either acute or chronic immune response. In this chapter we describe a protocol to isolate immune cells from T. cruzi-infected murine cardiac tissue and to determine the percentage, absolute number, phenotype, and functionality of monocytes and macrophages by using flow cytometry. Moreover, we describe the parameters to discriminate between resident and infiltrating mononuclear phagocytic cells within infected hearts. The investigations in this field will provide mechanistic insights about the roles of these innate immune cells in the context of a clinically relevant target tissue.


Assuntos
Doença de Chagas/imunologia , Citometria de Fluxo/métodos , Coração/parasitologia , Macrófagos/imunologia , Monócitos/imunologia , Trypanosoma cruzi/imunologia , Animais , Antígenos CD/análise , Antígenos CD/imunologia , Separação Celular/métodos , Células Cultivadas , Doença de Chagas/parasitologia , Citocinas/análise , Citocinas/imunologia , Humanos , Macrófagos/citologia , Macrófagos/parasitologia , Camundongos , Monócitos/citologia , Monócitos/parasitologia , Perfusão/métodos
19.
Parasitol Res ; 118(5): 1593-1599, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30852640

RESUMO

The present study aimed to isolate and genotype strains of T. gondii from pigs slaughtered for human consumption in South Brazil. Blood and tissues (heart, diaphragm, liver, tongue, and masseter) from 400 animals were collected at two slaughterhouses. Sera were obtained, and antibodies against T. gondii were detected by both indirect fluorescence antibody test (IFAT) and modified agglutination test (MAT). The tissues of animals that tested positive in MAT, IFAT, or both (cut-off ≥ 64) were bioassayed. Twenty-six (6.5%) of the 400 animals were positive by serology. A total of 18 (69.2%) out of those 26 were positive in the mouse bioassay. The isolates were characterized by using 10 PCR-RFLP genetic markers. Fourteen isolates were fully genotyped, and four isolates were genotyped using nine of the 10 markers. All isolates belonged to ToxoDB PCR-RFLP genotype #206. The present study reports on genotype #206 in pigs for the first time, and it confirms the atypical nature of the Brazilian T. gondii isolates. Additionally, even with low levels of antibodies detected in pig herds, pork presents a T. gondii infection risk for humans.


Assuntos
Doenças Transmitidas por Alimentos/parasitologia , Doenças dos Suínos/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Matadouros , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio , Brasil , Técnica Indireta de Fluorescência para Anticorpo , Marcadores Genéticos , Variação Genética , Genótipo , Coração/parasitologia , Humanos , Fígado/parasitologia , Camundongos , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Carne Vermelha/parasitologia , Suínos , Toxoplasmose Animal/sangue
20.
Parasitol Res ; 118(4): 1331-1335, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30783860

RESUMO

The present study evaluated the distribution and viability of Toxoplasma gondii tissue cysts in the organs and Brazilian commercial cuts of experimentally infected pigs. The pigs were infected with 3 × 103 oocysts of the T. gondii isolate TgCkBr57 (Type BrII). Mouse bioassays were performed on the brain, retina, tongue, diaphragm, and heart as well as the following muscle cuts: loin (longissimus), coppa (longissimus, spinalis dorsi, rhomboideus), tenderloin (psoas major), outside flat (biceps femoris), topside (semimembranosus), and top sirloin (gluteus medius). Toxoplasma gondii was isolated from the coppa, heart, diaphragm, and tongue of three pigs; from the tenderloin, outside flat, and brain of two pigs; and from the top sirloin and loin of one pig. Thus, the viability of T. gondii cysts was observed in all of the organs and cuts evaluated (except for the topside and retina), demonstrating the broad distribution of this parasite in pig organs and commercial meat cuts, and the importance of this species as a source of human infection.


Assuntos
Carne/parasitologia , Doenças dos Suínos/parasitologia , Suínos/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Encéfalo/parasitologia , Brasil , Diafragma/parasitologia , Feminino , Coração/parasitologia , Humanos , Camundongos , Oocistos/isolamento & purificação , Retina/parasitologia , Língua/parasitologia
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