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1.
J Helminthol ; 94: e117, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31948494

RESUMO

Metacercariae of various species within the genus Holostephanus Szidat, 1936 (Trematoda: Digenea: Cyathocotylidae) occur in muscles of both farmed and wild fish, including common carp (Cyprinus carpio Linnaeus, 1758). The life cycle includes a snail as first intermediate host, fish as second intermediate host and birds or mammals as final hosts. We studied the zoonotic potential and the viability of Holostephanus metacercariae from common carp following exposure to various physical and chemical treatments. Muscle tissue samples of common carp specimens from a fish farm in the north-eastern part of Hungary were examined and metacercariae recovered. The zoonotic potential was evaluated experimentally by using small mammals as models (albino mice, n = 2; and Syrian hamsters, n = 4) infected per os with Holostephanus cysts. Parallelly, Metagonimus metacercariae were used as positive controls. We could not confirm the zoonotic potential of Holostephanus metacercariae as they did not survive in the mammalian intestine whereas Metagonimus metacercariae developed to the adult stage. We assessed the viability of metacercariae isolated from common carp specimens during exposure to different physical treatments (temperatures of -18°C, +20°C, +40°C and +60°C) and chemical agents (5% and 10% acetic acid and 10% sodium chloride (NaCl)). Metacercariae lost viability by freezing at -18°C (2 h), heating at 60°C (20 min), incubation in 5% and 10% acetic acid (5 min) and 10% NaCl (2 h). These methods served as models to investigate the effectiveness of food preparation techniques (such as cold and hot smoking, freezing, salting and pickling) on the survival of metacercariae.


Assuntos
Carpas/parasitologia , Produtos Pesqueiros/parasitologia , Metacercárias/isolamento & purificação , Trematódeos , Infecções por Trematódeos/veterinária , Ácido Acético/farmacologia , Animais , Bioensaio/métodos , Inocuidade dos Alimentos/métodos , Congelamento , Estágios do Ciclo de Vida , Mesocricetus/parasitologia , Metacercárias/patogenicidade , Camundongos , Músculos/parasitologia , Cloreto de Sódio/farmacologia , Temperatura , Trematódeos/isolamento & purificação , Infecções por Trematódeos/tratamento farmacológico , Infecções por Trematódeos/transmissão , Zoonoses/parasitologia
2.
Exp Mol Pathol ; 110: 104274, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31226265

RESUMO

The food-borne liver trematode Opisthorchis felineus causes severe liver damage, including fibrosis. This study shows a comparison of the characteristics between cholangiofibrosis and periductal fibrosis in infected people and in the golden hamster as an experimental model. Comparative evaluation was carried out regarding collagen composition, the number of basic-producing cells, and extracellular-matrix degradation. The results revealed that characteristics of chronic opisthorchiasis due to O. felineus infection in humans and in Syrian hamsters are similar and include well-pronounced development of fibrotic complications in the liver parenchyma. Besides, a difference in fibrogenesis development was demonstrated between chronic O. felineus infection and noninfectious cholecystitis. In this study, we for the first time compared fibrogenesis between humans and model animals against the background of chronic O. felineus infection.


Assuntos
Cirrose Hepática/parasitologia , Mesocricetus/parasitologia , Opistorquíase/parasitologia , Opisthorchis/fisiologia , Animais , Doença Crônica , Colágeno Tipo I/metabolismo , Cricetinae , Modelos Animais de Doenças , Humanos , Fígado/metabolismo , Fígado/parasitologia , Fígado/patologia , Cirrose Hepática/metabolismo , Mesocricetus/metabolismo , Opistorquíase/metabolismo
3.
Int J Parasitol ; 49(8): 615-624, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31136746

RESUMO

Facilitated by the Schistosoma mansoni genome project, multiple transcriptomic studies were performed over the last decade to elucidate gene expression patterns among different developmental stages of the complex schistosome life cycle. While these analyses enable the identification of candidate genes with key functions in schistosome biology, a diverse molecular tool set is needed that allows comprehensive functional characterization at the single gene level. This includes the availability of reliable reference genes to confirm changes in the transcription of genes of interest over different biological samples and experimental conditions. In particular, the investigation of one key aspect of schistosome biology, the pairing-dependent gene expression in females and males, requires knowledge on reference genes that are expressed independently of both pairing and of in vitro culture effects. Therefore, the present study focused on the identification of quantitative reverse transcription (qRT)-PCR reference genes suitable for the investigation of pairing-dependent gene expression in the S. mansoni male. The "pipeline" we present here is based on qRT-PCR analyses of high biological replication combined with three different statistical analysis tools, BestKeeper, geNorm, and NormFinder. Our approach resulted in a statistically robust ranking of 15 selected reference genes with respect to their transcription stability between pairing-unexperienced and -experienced males. We further tested the top seven candidate genes for their transcription stability during invitro culture of adult S. mansoni. Of these, the two most suitable reference genes were used to investigate the influence of the pairing contact on the transcription of genes of interest, comprising a tyrosine decarboxylase gene Smtdc1, an ebony ortholog Smebony, and the follistatin ortholog Smfst in S. mansoni males. Performing pairing, separation and re-pairing experiments with adult S. mansoni in vitro, our results indicate for the first time that pairing can act as a molecular on/off-switch of specific genes to strictly control their expression in schistosome males.


Assuntos
Expressão Gênica/genética , Reação em Cadeia da Polimerase em Tempo Real , Schistosoma mansoni/genética , Algoritmos , Animais , Biomphalaria/parasitologia , Cricetinae , Feminino , Masculino , Mesocricetus/parasitologia , RNA de Helmintos/isolamento & purificação , Valores de Referência
4.
Parasitol Res ; 117(10): 3157-3168, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30022292

RESUMO

A variety of clinical forms of American cutaneous leishmaniasis (ACL) caused by Leishmania braziliensis, as well as differing immune responses of patients, have been reported for an ACL focus in the state of Minas Gerais, Brazil. In addition, two genetic profiles of L. braziliensis have been described, of which one variant profile (hsp70-variant) has been associated with atypical lesions. We investigated the biological behavior of genetic variant strains of L. braziliensis isolated from patients with different clinical manifestations of ACL. Experimental infections were performed with golden hamsters for five L. braziliensis strains in standardized doses of 1 × 106 parasites per inocula. The characteristics of skin lesions, histopathological features, and parasite burden were independently analyzed at 30 and 60 days post-infection. The data revealed distinct patterns in the onset time of visible skin lesions as well as in lesion size and parasite burden among the strains. The extent and density of the inflammatory infiltrate differed among strains, although cellular composition of granulomas appeared similar. Multivariate analysis indicated the occurrence of two clusters: one comprising native strains (cluster 1) and one comprising the reference strain (cluster 2). Within cluster 1, the genetic variants of L. braziliensis did not group with the non-variant strain suggesting that the distinct patterns of biological behavior of these strains could be associated with the known genetic diversity previously described for them.


Assuntos
Variação Genética/genética , Leishmania braziliensis/genética , Leishmaniose Cutânea/patologia , Pele/patologia , Adulto , Animais , Brasil/epidemiologia , Cricetinae , Proteínas de Choque Térmico HSP70/genética , Humanos , Leishmania braziliensis/classificação , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Masculino , Mesocricetus/parasitologia , Pele/parasitologia
5.
J Mol Diagn ; 20(2): 253-263, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29355825

RESUMO

Several methods have been developed for the detection of Leishmania, mostly targeting the minicircle kinetoplast DNA (kDNA). A new RNA real-time quantitative PCR (qPCR) assay was developed targeting the conserved and highly expressed spliced-leader (SL) mini-exon sequence. This study compared the limits of detection of various real-time PCR assays in hamsters infected with Leishmania infantum, in spiked human blood, and in clinical blood samples from visceral leishmaniasis patients. The SL-RNA assay showed an excellent analytical sensitivity in tissues (0.005 and 0.002 parasites per mg liver and spleen, respectively) and was not prone to false-positive reactions. Evaluation of the SL-RNA assay on clinical samples demonstrated lower threshold cycle values than the kDNA qPCR, an excellent interrun stability of 97%, a 93% agreement with the kDNA assay, and an estimated sensitivity, specificity, and accuracy of 93.2%, 94.3%, and 93.8%, respectively. The SL-RNA qPCR assay was equally efficient for detecting Leishmania major, Leishmania tropica, Leishmania mexicana, Leishmania guayensis, Leishmania panamensis, Leishmania braziliensis, L. infantum, and Leishmania donovani and revealed similar SL-RNA levels in the different species and the occurrence of polycistronic SL-containing transcripts in Viannia species. Collectively, this single SL-RNA qPCR assay enables universal Leishmania detection and represents a particularly useful addition to the widely used kDNA assay in clinical studies in which the detection of viable parasites is pivotal to assess parasitological cure.


Assuntos
DNA de Cinetoplasto/análise , Leishmania infantum/genética , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico , Mesocricetus/parasitologia , RNA Líder para Processamento/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Criança , Pré-Escolar , Cricetinae , Confiabilidade dos Dados , Feminino , Humanos , Fígado/parasitologia , Sensibilidade e Especificidade , Baço/parasitologia
6.
PLoS Negl Trop Dis ; 11(10): e0006044, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29088234

RESUMO

BACKGROUND: Opisthorchiasis is a parasitic infection caused by the liver flukes of the Opisthorchiidae family. Both experimental and epidemiological data strongly support a role of these parasites in the etiology of the hepatobiliary pathologies and an increased risk of intrahepatic cholangiocarcinoma. Understanding a functional link between the infection and hepatobiliary pathologies requires a detailed description a host-parasite interaction on different levels of biological regulation including the metabolic response on the infection. The last one, however, remains practically undocumented. Here we are describing a host response on Opisthorchiidae infection using a metabolomics approach and present the first exploratory metabolomics study of an experimental model of O. felineus infection. METHODOLOGY AND PRINCIPAL FINDINGS: We conducted a Nuclear Magnetic Resonance (NMR) based longitudinal metabolomics study involving a cohort of 30 animals with two degrees of infection and a control group. An exploratory analysis shows that the most noticeable trend (30% of total variance) in the data was related to the gender differences. Therefore further analysis was done of each gender group separately applying a multivariate extension of the ANOVA-ASCA (ANOVA simultaneous component analysis). We show that in the males the infection specific time trends are present in the main component (43.5% variance), while in the females it is presented only in the second component and covers 24% of the variance. We have selected and annotated 24 metabolites associated with the observed effects and provided a physiological interpretation of the findings. CONCLUSIONS: The first exploratory metabolomics study an experimental model of O. felineus infection is presented. Our data show that at early stage of infection a response of an organism unfolds in a gender specific manner. Also main physiological mechanisms affected appear rather nonspecific (a status of the metabolic stress) the data provides a set of the hypothesis for a search of the more specific metabolic markers of the Opisthorchiidae infection.


Assuntos
Modelos Animais de Doenças , Mesocricetus , Opistorquíase/parasitologia , Opisthorchis/fisiologia , Animais , Cricetinae , Feminino , Espectroscopia de Ressonância Magnética , Masculino , Mesocricetus/parasitologia , Modelos Animais
7.
Parasitol Res ; 116(11): 3239-3242, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28956157

RESUMO

In this survey, intestinal helminths from pet rodents in Mérida, México, were analyzed. A total of 46 mice Mus musculus, 28 hamsters Mesocricetus auratus, 23 rats Rattus norvegicus, and 1 gerbil Meriones unguiculatus were purchased from six pet shops and one black market for wildlife in the city of Mérida. The overall prevalence of helminths in rodents was 61.2% (60/98). Six species of helminths were identified: the zoonotic cestode Rodentolepis nana, and the nematodes Aspiculuris tetraptera, Dentostomella translucida, Syphacia obvelata, Syphacia mesocriceti, and Syphacia muris. Of the 60 infected rodents, 25 (41.7%) harbored 2 or 3 species of helminths. Rodentolepis nana was found in 4.3% of mice and 17.9% of hamsters. This is the first report of infection with S. muris in pet rats. Considering the close physical contact between pet rodents and humans, the presence of R. nana in pets represents a potential risk of transmission, especially to children and immunocompromised individuals.


Assuntos
Cestoides/isolamento & purificação , Nematoides/isolamento & purificação , Oxyuroidea/isolamento & purificação , Animais de Estimação/parasitologia , Doenças dos Roedores/parasitologia , Animais , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Infecções por Cestoides/veterinária , Cricetinae , Feminino , Gerbillinae/parasitologia , Intestinos/parasitologia , Mesocricetus/parasitologia , México/epidemiologia , Camundongos , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/veterinária , Oxiuríase/epidemiologia , Oxiuríase/parasitologia , Oxiuríase/veterinária , Prevalência , Ratos , Inquéritos e Questionários
8.
Sci Rep ; 7(1): 6104, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28733676

RESUMO

In Brazil, human and canine visceral leishmaniasis is caused by infection with Leishmania infantum, a Protist parasite transmitted by blood-feeding female Lutzomyia longipalpis sand flies. The objective of this study was to determine if the odour of hamsters, infected with Le. infantum, was more attractive than the odour of the same hamsters, before they were infected. The attractiveness of odour collected from individual hamsters (n = 13), before they were infected, was compared in a longitudinal study, with the attractiveness of the odour of the same hamster in a Y-tube olfactometer bioassay, at a late stage of infection. The odour of six of the golden hamsters was significantly more attractive to 50% of the female sand flies at the end of infection compared to before infection and the odour of four of the golden hamsters was significantly more attractive to 75% of the female sand flies at the end of infection. These results strongly indicate that hamsters infected with Le. infantum become significantly more attractive to a greater proportion of female sand flies as the infection progresses.


Assuntos
Insetos Vetores/parasitologia , Leishmania infantum , Mesocricetus/parasitologia , Psychodidae/parasitologia , Animais , Feminino , Leishmania infantum/fisiologia , Masculino
9.
Bull Exp Biol Med ; 162(6): 773-776, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28429227
11.
Parasitol Int ; 65(6 Pt A): 665-667, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27616150

RESUMO

The parasite Entamoeba histolytica causes intestinal amebiasis and amebic liver abscess as its main extraintestinal manifestation. To study the in vivo events related to inflammation and the interactions between hosts and parasites during amebiasis, we designed a novel model of host-parasite interactions using cellulose membrane dialysis bags containing E. histolytica trophozoites. A bag is placed into the hamster peritoneal cavity, as has been reported in previous studies of programmed cell death (PCD) in E. histolytica trophozoites. To determine if virulence factors such as cysteine proteinases (EhCP2 and EhCP5) and Gal/GalNAc lectin could be involved in the host-parasite interaction using this model, we examined the relative expression of the ehcp2 and ehcp5 genes and the carbohydrate recognition domain (crd) of Gal/GalNAc lectin using real-time quantitative PCR (qRT-PCR). All analyzed genes were over-expressed 0.5h after the initiation of the host-parasite interaction and were then progressively down-regulated. However, Gal/GalNAc lectin had the greatest increase in gene expression 1.5h after host-parasite interaction; Gal/GalNAc lectin had a 250-fold increase with respect to the axenically grown trophozoites, which over-express Gal/GalNAc lectin in in vivo models. These results support the important role of these molecules in the initiation of cell damage by E. histolytica.


Assuntos
Acetilgalactosamina/metabolismo , Cisteína Endopeptidases/metabolismo , Entamoeba histolytica/metabolismo , Entamebíase/parasitologia , Mesocricetus/parasitologia , Animais , Cricetinae , Cisteína Endopeptidases/genética , Disenteria Amebiana/parasitologia , Entamoeba histolytica/genética , Interações Hospedeiro-Parasita , Humanos , Lectinas/metabolismo , Abscesso Hepático Amebiano/parasitologia , Masculino , Proteínas de Protozoários/genética , Trofozoítos/patologia
12.
Korean J Parasitol ; 53(5): 627-39, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26537043

RESUMO

Metagonimus yokogawai (Katsurada, 1912) Katsurada, 1912 (Trematoda: Heterophyidae) is parasitic in the small intestine of mammals including man and birds in Far Eastern Russia, Korea, Japan, China, and Taiwan. In the present study, the metacercariae and adults of M. yokogawai were redescribed to designate a neotype of this fluke together with reviews of previous studies including study histories from the first discovery to now. We particularly, attempted to review the study histories and morphological descriptions of M. yokogawai for the species validity, and compared with the morphological characteristics and life cycles of the closely related species, Metagonimus takahashii and Metagonimus miyatai. Finally, we proposed a differential key for the 8 known Metagonimus species distributed in East Asia. Metacercariae were obtained from the body muscles of sweetfish (Plecoglossus altivelis) collected in the Asahi River at Takebe-cho, Kita-ku, Okayama City, Okayama Prefecture, Japan. Adults were recovered from the small intestine of Syrian golden hamsters, to which the metacercariae had been fed 14 days before. A neotype was selected out of the present adult specimens. The Asahi River at Takebo-cho became the type locality of M. yokogawai. In conclusion, the present review shows that M. yokogawai, M. takahashii, and M. miyatai are valid and discriminated by means of morphological characteristics.


Assuntos
Heterophyidae/anatomia & histologia , Heterophyidae/classificação , Estágios do Ciclo de Vida , Animais , Doenças dos Peixes/parasitologia , Helmintíase , Heterophyidae/isolamento & purificação , Enteropatias Parasitárias/veterinária , Japão , Mesocricetus/parasitologia , Microscopia , Osmeriformes/parasitologia , Doenças dos Roedores/parasitologia
13.
J Parasitol ; 101(5): 542-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26186584

RESUMO

Although Syrian golden hamsters are widely used as hosts for experimental infection by Schistosoma haematobium , surprisingly little is known about the course of infection and associated intensity (as defined by measures of parasite burden). As such, we sought to define inexpensive, simple, noninvasive, and accurate methods for assessing and predicting the severity of disease in S. haematobium -infected hamsters in order to prevent premature hamster sacrifice and unexpected morbidity and mortality. Through monitoring the weight and behavior of infected hamsters, we determined that the weight-loss patterns of infected hamsters are highly correlated with commonly used measures of the severity of infection (i.e., numbers of eggs passed in the stool, worm burdens, and total egg yields). In contrast, we found no significant correlation between hamster weight-loss patterns and egg yields from liver and intestinal tissues. Our findings suggest that a more complex relationship exists among worm burden, fecundity, and egg passage in the feces than previously appreciated. Regardless, our data may be useful for workers seeking to optimize harvests of S. haematobium eggs and worms from infected hamsters for downstream applications.


Assuntos
Modelos Animais de Doenças , Mesocricetus/parasitologia , Doenças dos Roedores/parasitologia , Esquistossomose Urinária/veterinária , Animais , Peso Corporal , Bulinus , Cricetinae , Fezes/parasitologia , Masculino , Mesocricetus/anatomia & histologia , Contagem de Ovos de Parasitas , Schistosoma haematobium/fisiologia , Esquistossomose Urinária/parasitologia , Sistema Urogenital/parasitologia
14.
Exp Parasitol ; 157: 78-83, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26160679

RESUMO

The Digenea (Platyhelminthes: Trematoda) are a diverse and complex group of internal metazoan parasites. These parasites can serve as hosts to obligate intracellular bacteria belonging to the genus Neorickettsia (Family: Anaplasmataceae). Neorickettsiae persist within all stages of the fluke life cycle and thus are maintained through vertical transmission. However, the low prevalence of Neorickettsia in nature limits study of their transmission biology at different steps of digenean life cycles. To resolve this dilemma, we have developed for the first time a laboratory model allowing to maintain Neorickettsia sp. through the whole life cycle of a digenean, Plagiorchis elegans. The laboratory life cycle of P. elegans consists of a snail first intermediate host, Lymnaea stagnalis, an aquatic arthropod second intermediate host, Culex pipiens (mosquito larva), and a vertebrate definitive host, Mesocricetus auratus (Syrian hamster). This paper focuses on the development of the laboratory life cycle, as well as outlines its potential uses in studying the transmission biology of Neorickettsia and its evolutionary relationship within its digenean host.


Assuntos
Culex/parasitologia , Lymnaea/parasitologia , Mesocricetus/parasitologia , Neorickettsia/fisiologia , Simbiose , Trematódeos/microbiologia , Animais , Cricetinae , Insetos Vetores/parasitologia , Estágios do Ciclo de Vida , Camundongos , Modelos Biológicos , Doenças dos Roedores/parasitologia , Doenças dos Roedores/transmissão , Trematódeos/crescimento & desenvolvimento , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/transmissão , Infecções por Trematódeos/veterinária
15.
BMC Immunol ; 15: 38, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25424735

RESUMO

BACKGROUND: The Syrian golden hamster (Mesocricetus aureus) has been used as a model to study infections caused by a number of human pathogens. Studies of immunopathogenesis in hamster infection models are challenging because of the limited availability of reagents needed to define cellular and molecular determinants. RESULTS: We sequenced a hamster cDNA library and developed a first-generation custom cDNA microarray that included 5131 unique cDNAs enriched for immune response genes. We used this microarray to interrogate the hamster spleen response to Leishmania donovani, an intracellular protozoan that causes visceral leishmaniasis. The hamster model of visceral leishmaniasis is of particular interest because it recapitulates clinical and immunopathological features of human disease, including cachexia, massive splenomegaly, pancytopenia, immunosuppression, and ultimately death. In the microarray a differentially expressed transcript was identified as having at least a 2-fold change in expression between uninfected and infected groups and a False Discovery Rate of <5%. Following a relatively silent early phase of infection (at 7 and 14 days post-infection only 8 and 24 genes, respectively, were differentially expressed), there was dramatic upregulation of inflammatory and immune-related genes in the spleen (708 differentially expressed genes were evident at 28 days post-infection). The differentially expressed transcripts included genes involved in inflammation, immunity, and immune cell trafficking. Of particular interest there was concomitant upregulation of the IFN-γ and interleukin (IL)-4 signaling pathways, with increased expression of a battery of IFN-γ- and IL-4-responsive genes. The latter included genes characteristic of alternatively activated macrophages. CONCLUSIONS: Transcriptional profiling was accomplished in the Syrian golden hamster, for which a fully annotated genome is not available. In the hamster model of visceral leishmaniasis, a robust and functional IFN-γ response did not restrain parasite load and progression of disease. This supports the accumulating evidence that macrophages are ineffectively activated to kill the parasite. The concomitant expression of IL-4/IL-13 and their downstream target genes, some of which were characteristic of alternative macrophage activation, are likely to contribute to this. Further dissection of mechanisms that lead to polarization of macrophages toward a permissive state is needed to fully understand the pathogenesis of visceral leishmaniasis.


Assuntos
Citocinas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Leishmaniose Visceral/genética , Leishmaniose Visceral/imunologia , Baço/metabolismo , Baço/parasitologia , Animais , Análise por Conglomerados , Cricetinae , Citocinas/metabolismo , DNA Complementar/genética , Progressão da Doença , Etiquetas de Sequências Expressas , Ontologia Genética , Humanos , Interferon gama/metabolismo , Leishmania donovani/imunologia , Mesocricetus/imunologia , Mesocricetus/parasitologia , Anotação de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Componente Principal , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/genética , Baço/patologia , Regulação para Cima/genética
16.
PLoS One ; 9(6): e97911, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24926878

RESUMO

The present study includes cloning and expression of recombinant Leishmania donovani histone proteins (rLdH2B, rLdH3, rLdH2A and rLdH4), assessment of their immunogenicity in Leishmania infected cured patients/endemic contacts as well as in cured hamsters and finally evaluation of their prophylactic efficacy in hamsters against L. donovani challenge. All recombinant proteins were expressed and purified from the heterologous bacterial host system. Leishmania infected cured patients/endemic contacts as well as cured hamsters exhibited significantly higher proliferative responses to individual recombinant histones and their pooled combination (rLdH2B+rLdH3+rLdH2A+rLdH4) than those of L.donovani infected hosts. The L.donovani soluble antigens (SLD) stimulated PBMCs of cured/exposed and Leishmania patients to produce a mixed Thl/Th2-type cytokine profile, whereas rLdH2B, rLdH3, rLdH2A, rLdH4 and pooled combination (rLdH2-4) stimulated the production of Th1 cytokines IFN-γ, IL-12 and TNF-α but not Th2 cytokines IL-4 or IL-10. The immunogenicity of these histone proteins along with their combination was also checked in cured hamsters where they stimulated higher lymphoproliferation and Nitric oxide production in lymphocytes of cured hamsters than that of infected controls. Moreover, significantly increased IgG2 response, an indicative of cell mediated immunity, was observed in cured hamsters against these individual proteins and their combination as compared to infected hamsters. Further, it was demonstrated that rLdH2B, rLdH3, rLdH2A and rLdH4 and pooled combination were able to provide considerable protection for hamsters against L. donovani challenge. The efficacy was supported by the increased inducible Nitric Oxide Synthase (iNOS) mRNA transcripts and Th1-type cytokines--IFN-γ, IL-12 and TNF-α and down-regulation of IL-4, IL-10 and TGF-ß. Hence, it is inferred that pooled rLdH2-4 elicits Thl-type of immune responses exclusively and confer considerable protection against experimental Visceral Leishmaniasis.


Assuntos
Antígenos de Protozoários/imunologia , Histonas/metabolismo , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/prevenção & controle , Mesocricetus/parasitologia , Adolescente , Adulto , Animais , Cricetinae , Citocinas/genética , Citocinas/metabolismo , Feminino , Histonas/genética , Humanos , Imunização/métodos , Leishmania donovani/isolamento & purificação , Leishmania donovani/metabolismo , Leishmaniose Visceral/veterinária , Masculino , Mesocricetus/imunologia , Pessoa de Meia-Idade , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Adulto Jovem
17.
PLoS One ; 9(2): e89412, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24586759

RESUMO

Leishmaniasis remains one of the world's most devastating neglected tropical diseases. It mainly affects developing countries, where it often co-exists with chronic malnutrition, one of the main risk factors for developing the disease. Few studies have been published, however, on the relationship between leishmaniasis progression and malnutrition. The present paper reports the influence of protein malnutrition on the immune response and visceral disease development in adult hamsters infected with Leishmania infantum fed either standard or low protein diets. The low protein diet induced severe malnutrition in these animals, and upon infection with L. infantum 33% had severe visceral leishmaniasis compared to only 8% of animals fed the standard diet. The infected, malnourished animals showed notable leukocyte depletion, mild specific antibody responses, impairment of lymphoproliferation, presence of parasites in blood (16.67% of the hamsters) and significant increase of the splenic parasite burden. Animals fed standard diet suffered agranulocytosis and monocytopenia, but showed stronger specific immune responses and had lower parasite loads than their malnourished counterparts. The present results show that protein malnutrition promotes visceral leishmaniasis and provide clues regarding the mechanisms underlying the impairment of the immune system.


Assuntos
Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Desnutrição/imunologia , Desnutrição/parasitologia , Mesocricetus/imunologia , Mesocricetus/parasitologia , Proteínas/metabolismo , Animais , Doença Crônica , Cricetinae , Dieta com Restrição de Proteínas/métodos , Leishmania infantum/imunologia , Leishmaniose Visceral/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Leucócitos/parasitologia , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/metabolismo , Transtornos Linfoproliferativos/parasitologia , Masculino , Desnutrição/metabolismo , Mesocricetus/metabolismo , Doenças Negligenciadas/imunologia , Doenças Negligenciadas/metabolismo , Doenças Negligenciadas/parasitologia , Proteínas/imunologia
18.
J Morphol ; 274(9): 965-72, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23630154

RESUMO

The ultrastructure of the mature spermatozoon of the type genus of the Plagiorchiidae Plagiorchis elegans (Rudolphi, 1802), a parasite of the Golden hamster, Mesocricetus auratus is described. This study is the first ultrastructural study of the spermatozoon of a Plagiorchis, the second of a plagiorchiid species and only the third in the Plagiorchioidea. Previously data on spermatozoon ultrastructure existed only for the plagiorchiid Enodiotrema reductum and the omphalometrid Rubenstrema exasperatum. The mature spermatozoon of P. elegans exhibited the general pattern described in most digenean species, namely two axonemes of the 9 + "1" Trepaxonemata pattern, nucleus, mitochondria, external ornamentation of the plasma membrane, spine-like bodies, and glycogen granules. However, the rather typical expansion of the plasma membrane is not found in P. elegans. Another peculiarity of the spermatozoon of P. elegans is the presence of a structure called thin cytoplasm termination. Spermatozoon ultrastructure of P. elegans is compared with that of E. reductum and R. exasperatum. Spermatozoon of P. elegans conforms to the general pattern described in E. reductum. Thus, this study further expands our knowledge on the spermatozoon ultrastructure among the members of the Plagiorchioidea, one of the most phylogenetically derived groups of the digenea.


Assuntos
Espermatozoides/ultraestrutura , Trematódeos/ultraestrutura , Animais , Axonema/ultraestrutura , Membrana Celular/ultraestrutura , Cricetinae , Masculino , Mesocricetus/parasitologia , Mitocôndrias/ultraestrutura
19.
Parasitol Int ; 61(1): 107-11, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21807116

RESUMO

The structure and organization of the nervous system has been documented for various helminth parasites. However, the neuroanatomy of the carcinogenic liver fluke, Opisthorchis viverrini has not been described. This study therefore investigated the organization of the nervous system of this fluke using cholinesterase activity, aminergic and peptidergic (FMRFamide-like peptides) immunostaining to tag major neural elements. The nervous system, as detected by acetylcholinesterase (AchE) reaction, was similar in newly excysted metacercariae, migrating juveniles and adult parasites. In these stages, there were three pairs (dorsal, ventral and lateral) of bilaterally symmetrical longitudinal nerve cords and two cerebral ganglia. The ventral nerve cords and the cerebral ganglia were well-developed and exhibited strong AchE reactivity, as well as aminergic and FMRFamide-like immunoreactivity. Numerous immunoreactive nerve cell bodies were observed around the inner surface of the ventral sucker. Fine FMRFamide-like peptides immunopositive nerve fiber was rarely observed. Overall, the organization of the nervous system of O. viverrini is similar to other trematodes.


Assuntos
Opisthorchis/ultraestrutura , Acetilcolinesterase/química , Animais , Cricetinae , Cyprinidae/parasitologia , FMRFamida/química , Doenças dos Peixes/parasitologia , Imunofluorescência , Mesocricetus/parasitologia , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/ultraestrutura , Opisthorchis/crescimento & desenvolvimento
20.
Parasitol Res ; 110(2): 799-808, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21786067

RESUMO

Eggs of most species digenean flukes hatch in the external environment to liberate larvae that seek and penetrate a snail intermediate host. Those of the human liver flukes, Opisthorchis viverrini, hatch within the gastrointestinal canal of their snail hosts. While adult parasites are primarily responsible for the pathology in cases of human opisthorchiasis, their eggs also contribute by inducing granulomata and in serving as nidi for gallstone formation. In view of the peculiar biology of O. viverrini eggs and their contribution to pathology, we investigated embryogenesis in this species by light and transmission electron microscopy. Egg development was traced from earliest stages of coalescence in the ootype until full embryonation in the distal region of the uterus. Fully mature eggs were generally impermeable to resin and could not be examined by conventional electron microscopy methods. However, the use of high-pressure freezing and freeze-substitution fixation of previously fixed eggs enabled the internal structure of mature eggs, particularly the subshell envelopes, to be elucidated. Fertilization occurs in the ootype, and the large zygote is seen therein with a single spermatozoon wrapped around its plasma membrane. As the zygote begins to divide, the spent vitellocytes are pushed to the periphery of the eggs, where they progressively degrade. The early eggshell is formed in the ootype by coalescing eggshell precursor material released by approximately six vitelline cells. The early eggs have a thinner eggshell and are larger than, but lack the characteristic shape of, mature eggs. Characteristic shell ornamentation, the "muskmelon" appearance of eggs, appears after eggshell polymerization in the ootype. Pores are not present in the shell of O. viverrini eggs. The inner and outer envelopes are poorly formed in this species, with the outer envelope evident beneath the eggshell at the opercular pole of the mature egg. The miracidium has a conical anterior end that lacks the distinctive lamellar appearance of the terebratorium of other digeneans, such as the schistosomes. The miracidium is richly glandular, containing an apical gland in the anterior end, large cephalic gland, and posterior secretory glands. Each gland contains a secretory product with different structure. The paucity of vitelline cells associating with eggs, the reduced size of eggs, and reduced complexity of the extraembryonic envelopes are interpreted as adaptations to the peculiar hatching biology of the miracidia.


Assuntos
Opisthorchis/crescimento & desenvolvimento , Opisthorchis/ultraestrutura , Animais , Cricetinae , Desenvolvimento Embrionário , Feminino , Mesocricetus/parasitologia , Microscopia , Óvulo/ultraestrutura , Útero/ultraestrutura
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