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1.
J Helminthol ; 98: e36, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38659305

RESUMO

New morphological and molecular data were generated for trematodes recovered from the intestines of the fish Pseudaspius hakonensis from two locations in the south of the Russian Far East. Morphologically, these trematodes are identical to Pseudozoogonoides ugui (Microphalloidea: Zoogonidae) from Japan. According to results of phylogenetic analysis based on 28S rDNA sequence data, P. ugui was closely related to Zoogonoides viviparus, and P. subaequiporus appears as a sister taxon to these two species. Genetic distance values, calculated based on both 28S rDNA and ITS2 rDNA, between P. ugui and Z. viviparus represents an interspecific differentiation level. Our results have an ambiguous explanation, indicating that the implication of the presence of one or two compact vitellarial aggregations for the differentiation of Zoogonoides and Pseudozoogonoides should be reconsidered or that our results open up the question of the taxonomical status of trematodes previously denoted as Z. viviparus and P. subaequiporus.


Assuntos
DNA de Helmintos , DNA Ribossômico , Doenças dos Peixes , Filogenia , RNA Ribossômico 28S , Trematódeos , Infecções por Trematódeos , Animais , Trematódeos/genética , Trematódeos/classificação , Trematódeos/anatomia & histologia , RNA Ribossômico 28S/genética , Doenças dos Peixes/parasitologia , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária , DNA de Helmintos/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Federação Russa , Análise de Sequência de DNA , Intestinos/parasitologia
2.
Parasitology ; 151(4): 440-448, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38525532

RESUMO

A new species of Moniliformis, M. tupaia n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analysing the nuclear 18S, ITS, 28S regions and mitochondrial cox1 and cox2 genes), based on specimens collected from the intestine of the northern tree shrew Tupaia belangeri chinensis Anderson (Scandentia: Tupaiidae) in China. Phylogenetic analyses show that M. tupaia n. sp. is a sister to M. moniliformis in the genus Moniliformis, and also challenge the systematic status of Nephridiacanthus major. Moniliformis tupaia n. sp. represents the third Moniliformis species reported from China.


Assuntos
Acantocéfalos , Filogenia , Tupaia , Animais , Tupaia/parasitologia , Tupaia/genética , China , Acantocéfalos/genética , Acantocéfalos/classificação , Acantocéfalos/anatomia & histologia , Acantocéfalos/ultraestrutura , Helmintíase Animal/parasitologia , Microscopia Eletrônica de Varredura/veterinária , DNA de Helmintos/genética , RNA Ribossômico 18S/genética , Feminino , Masculino , RNA Ribossômico 28S/genética , Intestinos/parasitologia
3.
Poult Sci ; 103(4): 103486, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350385

RESUMO

Eimeria maxima microneme protein 3 (EmMIC3) is pivotal in the initial recognition and attachment of E. maxima sporozoites to host cells. EmMIC3 comprises 5 tandem Type I microneme adhesive repeat (MAR) domains, among which MAR2 of EmMIC3 (EmMAR2) has been identified as the primary determinant of EmMIC3-mediated tissue tropism. Nonetheless, the mechanisms through which EmMAR2 guides the parasite to its invasion site through interactions with host receptors remained largely uncharted. In this study, we employed yeast two-hybrid (YTH) screening assays and shotgun LC-MS/MS analysis to identify EmMAR2 receptors in chicken intestine epithelial cells. ATPase H+ transporting V1 subunit G1 (ATP6V1G1), receptor accessory protein 5 (REEP5), transmembrane p24 trafficking protein (TMED2), and delta 4-desaturase sphingolipid 1 (DEGS1) were characterized as the 4 receptors of EmMAR2 by both assays. By blocking the interaction of EmMAR2 with each receptor using specific antibodies, we observed varying levels of inhibition on the invasion of E. maxima sporozoites, and the combined usage of all 4 antibodies resulted in the most pronounced inhibitory effect. Additionally, the spatio-temporal expression profiles of ATP6V1G1, REEP5, TMED2, and DEGS1 were assessed. The tissue-specific expression patterns of EmMAR2 receptors throughout E. maxima infection suggested that ATP6V1G1 and DEGS1 might play a role in early-stage invasion, whereas TMED2 could be involved in middle and late-stage invasion and REEP5 and DEGS1 may participate primarily in late-stage invasion. Consequently, E. maxima may employ a multitude of ligand-receptor interactions to drive invasion during different stages of infection. This study marks the first report of EmMAR2 receptors at the interface between E. maxima and the host, providing insights into the invasion mechanisms of E. maxima and the pathogenesis of coccidiosis.


Assuntos
Coccidiose , Eimeria tenella , Eimeria , Doenças das Aves Domésticas , Animais , Galinhas/metabolismo , Cromatografia Líquida/veterinária , Micronema , Proteínas de Protozoários/genética , Espectrometria de Massas em Tandem/veterinária , Coccidiose/parasitologia , Coccidiose/veterinária , Intestinos/parasitologia , Células Epiteliais/metabolismo , Doenças das Aves Domésticas/prevenção & controle
4.
Braz J Biol ; 83: e275748, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970905

RESUMO

The tambaqui (Colossoma macropomum) is a species of great economic importance for fish farming in the Brazilian Amazon, and acanthocephaliasis caused by Neoechinorhynchus buttnerae (Golvan 1956) represents an obstacle to its production due to it causing severe morphological damage to the intestinal mucosa, thus impairing the absorption of nutrients and causing weight loss in the fish. Therefore, the establishment of in vitro protocols for evaluation of anthelmintic drugs is the first step to development of effective measures for in vivo control of this endoparasite. The present study evaluated the in vitro survival of N. buttnerae maintained in Eagle's minimum essential medium under different culture conditions. Three assays were carried out to evaluate whether temperature, supplementation with the antibiotics penicillin and streptomycin, and culture medium replacement or no replacement would influence the motility and morphology of the acanthocephalans. The results of the Kaplan-Meier analysis indicated that the use of culture in minimum essential medium together with penicillin and streptomycin prolonged the parasite's survival when kept at temperatures of 24 °C or 28 °C. We describe herein for first time an alternative protocol that is ideal for the in vitro culture of N. buttnerae. As such, this protocol ensures greater reliability in further in vitro studies with N. buttnerae.


Assuntos
Acantocéfalos , Caraciformes , Animais , Brasil , Reprodutibilidade dos Testes , Aquicultura , Intestinos/parasitologia , Penicilinas/farmacologia , Estreptomicina/farmacologia
5.
Nature ; 619(7971): 782-787, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37438520

RESUMO

Many communities in low- and middle-income countries globally lack sustainable, cost-effective and mutually beneficial solutions for infectious disease, food, water and poverty challenges, despite their inherent interdependence1-7. Here we provide support for the hypothesis that agricultural development and fertilizer use in West Africa increase the burden of the parasitic disease schistosomiasis by fuelling the growth of submerged aquatic vegetation that chokes out water access points and serves as habitat for freshwater snails that transmit Schistosoma parasites to more than 200 million people globally8-10. In a cluster randomized controlled trial (ClinicalTrials.gov: NCT03187366) in which we removed invasive submerged vegetation from water points at 8 of 16 villages (that is, clusters), control sites had 1.46 times higher intestinal Schistosoma infection rates in schoolchildren and lower open water access than removal sites. Vegetation removal did not have any detectable long-term adverse effects on local water quality or freshwater biodiversity. In feeding trials, the removed vegetation was as effective as traditional livestock feed but 41 to 179 times cheaper and converting the vegetation to compost provided private crop production and total (public health plus crop production benefits) benefit-to-cost ratios as high as 4.0 and 8.8, respectively. Thus, the approach yielded an economic incentive-with important public health co-benefits-to maintain cleared waterways and return nutrients captured in aquatic plants back to agriculture with promise of breaking poverty-disease traps. To facilitate targeting and scaling of the intervention, we lay the foundation for using remote sensing technology to detect snail habitats. By offering a rare, profitable, win-win approach to addressing food and water access, poverty alleviation, infectious disease control and environmental sustainability, we hope to inspire the interdisciplinary search for planetary health solutions11 to the many and formidable, co-dependent global grand challenges of the twenty-first century.


Assuntos
Agricultura , Ecossistema , Saúde da População Rural , Esquistossomose , Caramujos , Animais , Criança , Humanos , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Esquistossomose/transmissão , Caramujos/parasitologia , África Ocidental , Fertilizantes , Espécies Introduzidas , Intestinos/parasitologia , Água Doce , Plantas/metabolismo , Biodiversidade , Ração Animal , Qualidade da Água , Produção Agrícola/métodos , Saúde Pública , Pobreza/prevenção & controle , Organismos Aquáticos/metabolismo , Tecnologia de Sensoriamento Remoto
6.
Trends Parasitol ; 39(6): 414-422, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37076358

RESUMO

Intestinal helminths remain highly pervasive throughout the animal kingdom by modulating multiple aspects of the host immune response. The intestinal epithelium functions as a physical barrier as well as a sentinel innate immune tissue with the ability to sense and respond to infectious agents. Although helminths form intimate interactions with the epithelium, comprehensive knowledge about host-helminth interactions at this dynamic interface is lacking. In addition, little is known about the ability of helminths to directly shape the fate of this barrier tissue. Here, we review the diverse pathways by which helminths regulate the epithelium and highlight the emerging field of direct helminth regulation of intestinal stem cell (ISC) fate and function.


Assuntos
Helmintíase , Helmintos , Enteropatias Parasitárias , Animais , Mucosa Intestinal , Intestinos/parasitologia
7.
Poult Sci ; 102(4): 102537, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36867919

RESUMO

Infection with the protozoan parasite Eimeria can cause the economically devastating disease coccidiosis, which is characterized by gross tissue damage and inflammation resulting in blunted villi and altered intestinal homeostasis. Male broiler chickens at 21 d of age were given a single challenge with Eimeria acervulina. Temporal changes in intestinal morphology and gene expression were investigated at 0, 3, 5, 7, 10, and 14 d postinfection (dpi). There were increased crypt depths for chickens infected with E. acervulina starting at 3 dpi and continuing to 14 dpi. At 5 and 7 dpi, infected chickens had decreased Mucin2 (Muc2), and Avian beta defensin (AvBD) 6 mRNA at 5 and 7 dpi and decreased AvBD10 mRNA at 7 dpi compared to uninfected chickens. Liver-enriched antimicrobial peptide 2 (LEAP2) mRNA was decreased at 3, 5, 7, and 14 dpi compared to uninfected chickens. After 7 dpi, there was increased Collagen 3a1 and Notch 1 mRNA compared to uninfected chickens. Marker of proliferation Ki67 mRNA was increased in infected chickens from 3 to 10 dpi. In addition, the presence of E. acervulina was visualized by in situ hybridization (ISH) with an E. acervulina sporozoite surface antigen (Ea-SAG) probe. In E. acervulina infected chickens, Ea-SAG mRNA was only detectable on 5 and 7 dpi by both ISH and qPCR. To further investigate the site of E. acervulina infection, Ea-SAG and Muc2 probes were examined on serial sections. The Muc2 ISH signal was decreased in regions where the Ea-SAG ISH signal was present, suggesting that the decrease in Muc2 by qPCR may be caused by the loss of Muc2 in the localized regions where the E. acervulina had invaded the tissue. Eimeria acervulina appears to manipulate host cells by decreasing their defensive capabilities and thereby allows the infection to propagate freely. Following infection, the intestinal cells upregulate genes that may support regeneration of damaged intestinal tissue.


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Animais , Masculino , Eimeria/fisiologia , Galinhas/genética , Galinhas/parasitologia , Coccidiose/parasitologia , Coccidiose/veterinária , Intestinos/parasitologia , Esporozoítos , RNA Mensageiro/genética
8.
Gastroenterol. latinoam ; 34(2): 61-65, 2023. ilus
Artigo em Espanhol | LILACS | ID: biblio-1524718

RESUMO

We report a clinical case from a patient with alcoholic cirrhosis who had chronic anemia and carried out several endoscopic studies without evidence of active bleeding, a complementary study with endoscopic capsule was requested to search for a source of bleeding. In the analysis of laboratory data, the presence of hypereosinophilia stands out in parallel. The images obtained in the video capsule study show geoparasites helminth-type. After parasite treatment, anemia improves and the absolute eosinophil count is normalized.


Reportamos el caso de un paciente cirrótico por alcohol con anemia crónica quien se realizó varios estudios endoscópicos sin evidencia de sangrado activo, por tal motivo se solicitó estudio complementario con cápsula endoscópica para búsqueda de fuente de sangrado. En el análisis de los datos de laboratorio paralelamente destaca la presencia de hipereosinofilia. Las imágenes obtenidas en el estudio de la video cápsula muestran varios geoparásitos de tipo helmintos. Posterior al tratamiento antiparasitario mejora la anemia y se normaliza el recuento absoluto de eosinófilos.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia Gastrointestinal/etiologia , Enteropatias Parasitárias/diagnóstico , Fibrose/complicações , Eosinófilos , Hemorragia Gastrointestinal/diagnóstico , Anemia/complicações , Intestinos/parasitologia
9.
Zootaxa ; 5150(1): 83-96, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-36095759

RESUMO

The present paper summarizes acanthocephalan parasites of the family Illiosentidae Golvan, 1960, collected from the intestine of common carp (Cyprinus carpio L.) from Taihu Lake in Wuxi, Jiangsu Province, China. A total of 21 acanthocephalan specimens were found in 6 carps (prevalence of 35%). All the studied specimens were assigned to the family Illiosentidae based on the family-specific morphology of the worms and the presence of 8 cement glands in the males. However, the specimens recently found in common carp differed from all 14 extant genera of the family Illiosentidae in the structure of the reproductive system of both sexes, i.e. i) a vagina lacking a muscular sphincter; ii) the presence of a terminally pointed protruding tail end in the form of a dome with a muscular base; iii) the female genital muscles are fan-shaped cells, each of which has a nucleus and is not attached to the anterior wall of the body; iv) the muscular lip of the bursa of males repeats the curved shape of the posterior end of females, which en copula allows the lip of the bursa to seal to the posterior end of the female. Morphologically Neotegorhynchus n. g. is closest to the genus Tegorhynchus, but differs from it, in addition above features in i) the terminal position of the genital pores of females without a hollow genital vestibule and without a transverse cleft connected to the dorsal terminal genital pore, as in Tegorhynchus brevis; ii) cerebral ganglion at the border of the anterior and middle third of the proboscis vessel; iii) spherical cement reservoir. Molecular studies confirmed Neotegorhynchus n. g. as belonging to the family Illiosentidae, showing less than 98.9% sequence similarity in SSU rDNA and 81.8% in COI with the genus Dentitruncus. Therefore, a new acanthocephalan genus, Neotegorhynchus n. g., is erected, and Neotegorhynchus cyprini n. comb. is designated as the type species and its neotype.


Assuntos
Acantocéfalos , Carpas , Animais , DNA Ribossômico , Feminino , Intestinos/parasitologia , Masculino , Rios
10.
Nat Commun ; 13(1): 1725, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365634

RESUMO

Whipworms are large metazoan parasites that inhabit multi-intracellular epithelial tunnels in the large intestine of their hosts, causing chronic disease in humans and other mammals. How first-stage larvae invade host epithelia and establish infection remains unclear. Here we investigate early infection events using both Trichuris muris infections of mice and murine caecaloids, the first in-vitro system for whipworm infection and organoid model for live helminths. We show that larvae degrade mucus layers to access epithelial cells. In early syncytial tunnels, larvae are completely intracellular, woven through multiple live dividing cells. Using single-cell RNA sequencing of infected mouse caecum, we reveal that progression of infection results in cell damage and an expansion of enterocytes expressing of Isg15, potentially instigating the host immune response to the whipworm and tissue repair. Our results unravel intestinal epithelium invasion by whipworms and reveal specific host-parasite interactions that allow the whipworm to establish its multi-intracellular niche.


Assuntos
Helmintos , Tricuríase , Animais , Mucosa Intestinal , Intestinos/parasitologia , Mamíferos , Camundongos , Trichuris/fisiologia
11.
Dis Aquat Organ ; 148: 43-56, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35200158

RESUMO

As part of a study on parasitic infection in the African sharptooth catfish Clarias gariepinus, we found cysts of varying sizes in the stomach and intestine that contained myxospores with morphological features resembling those of the genus Henneguya. The present investigation was carried out with data on spore morphology and histopathology. Additionally, the myxozoan was identified using a molecular-based approach with 18S small subunit rDNA sequences. Based on the morphological characterization and tissue specificity of Myxozoa, 2 species of Henneguya were identified in the catfish stomach and intestine. Several histopathological changes were observed in the intestine which may affect fish performance and survival. The phylogenetic position of nucleotide sequences of the Henneguya species identified here were clustered with other fish-infecting Henneguya species. These sequences were deposited in GenBank. It appears that they potentially represent 2 species, denominated Henneguya sp. 1 and Henneguya sp. 2 according to the samples originating from the stomach and intestine, respectively. Although future investigations are needed for detailed morphological and molecular descriptions, this study documents the likely occurrence of infection with Henneguya noted for the first time, to our knowledge, in the digestive system of C. gariepinus in Egypt.


Assuntos
Peixes-Gato , Doenças dos Peixes , Myxozoa , Doenças Parasitárias em Animais , Animais , Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Intestinos/parasitologia , Myxozoa/genética , Doenças Parasitárias em Animais/parasitologia , Filogenia , Rios
12.
Parasit Vectors ; 15(1): 24, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022078

RESUMO

Baylisascaris procyonis is a nematode parasite of the raccoon (Procyon lotor), and it can be responsible for a severe form of larva migrans in humans. This parasite has been reported from many countries all over the world, after translocation of its natural host outside its native geographic range, North America. In the period between January and August 2021, 21 raccoons were cage-trapped and euthanized in Tuscany (Central Italy), in the context of a plan aimed at eradicating a reproductive population of this non-native species. All the animals were submitted for necroscopic examination. Adult ascariids were found in the small intestine of seven raccoons (prevalence 33.3%). Parasites have been identified as B. procyonis based on both morphometric and molecular approaches. The aim of the present article is to report the first finding of this zoonotic parasite from Italy, highlighting the sanitary risks linked to the introduction of alien vertebrate species in new areas.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Guaxinins/parasitologia , Zoonoses/parasitologia , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Feminino , Intestinos/parasitologia , Espécies Introduzidas , Itália/epidemiologia , Masculino , Zoonoses/epidemiologia
13.
Trends Parasitol ; 38(2): 101-103, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34953724

RESUMO

Animal models for studying immune responses to Cryptosporidium, a parasite that causes gastrointestinal disease, have been a challenge due to the parasite's poor infectivity in mice. Russler-Germain et al. discovered a 'commensal' strain of Cryptosporidium, capable of stable infection and vertical transmission, that elicits a T helper type 1 (Th1) response to promote intestinal homeostasis.


Assuntos
Criptosporidiose , Cryptosporidium , Animais , Criptosporidiose/parasitologia , Células Dendríticas/imunologia , Homeostase , Intestinos/parasitologia , Camundongos
14.
Cytokine ; 149: 155701, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34741881

RESUMO

The severity of chronic schistosomiasis has been mainly associated with the intensity and extension of the inflammatory response induced by egg-secreted antigens in the host tissue, especially in the liver and intestine. During acute schistosomiasis, eosinophils account for approximately 50% of the cells that compose the liver granulomas; however, the role of this cell-type in the pathology of schistosomiasis remains controversial. In the current study, we compared the parasite burden and liver immunopathological changes during experimental schistosomiasis in wild-type (WT) BALB/c mice and BALB/c mice selectively deficient for the differentiation of eosinophils (ΔdblGATA). Our data demonstrated that the absence of eosinophil differentiation did not alter the S. mansoni load or the liver retention of parasite eggs; however, there were significant changes in the liver immune response profile and tissue damage. S. mansoni infection in ΔdblGATA mice resulted in significantly lower liver concentrations of IL-5, IL-13, IL-33, IL-17, IL-10, and TGF-ß and higher concentrations of IFN-γ and TNF-α, as compared to WT mice. The changes in liver immune response observed in infected ΔdblGATA mice were accompanied by lower collagen deposition, but higher liver damage and larger granulomas. Moreover, the absence of eosinophils resulted in a higher mortality rate in mice infected with a high parasite load. Therefore, the data indicated that eosinophils participate in the establishment and/or amplification of liver Th-2 and regulatory response induced by S. mansoni, which is necessary for the balance between liver damage and fibrosis, which in turn is essential for modulating disease severity.


Assuntos
Eosinófilos/imunologia , Imunidade/imunologia , Hepatopatias/imunologia , Fígado/imunologia , Doenças Negligenciadas/imunologia , Esquistossomose mansoni/imunologia , Animais , Citocinas/imunologia , Modelos Animais de Doenças , Eosinófilos/parasitologia , Feminino , Fibrose/imunologia , Fibrose/parasitologia , Granuloma/imunologia , Granuloma/parasitologia , Intestinos/imunologia , Intestinos/parasitologia , Fígado/parasitologia , Hepatopatias/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Doenças Negligenciadas/parasitologia
15.
Parasitol Int ; 87: 102521, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34856387

RESUMO

We examined the effects of Eimeria pragensis infection on intestinal peristalsis, goblet cell proliferation and intestinal flora in C57BL/6 mice. Intestinal peristalsis was evaluated by radiography using barium at 7 days post-infection (p.i.). The intestinal peristalsis of E. pragensis-infected mice was significantly suppressed compared with uninfected control mice. Twenty-three mice were divided into 5 groups of 4 or 5 mice each; 2 groups of mice were infected with E. pragensis and the others were kept uninfected. At 7 days p.i., E. pragensis-infected and -uninfected mice were sacrificed to examine goblet cell numbers in the intestines, and significant decreases were observed only in the infected mice. Shiga toxin-producing Escherichia coli (STEC) O157:H7 was inoculated orally in mice both infected and uninfected with E. pragensis at 7 days p.i., with the remaining mice used as uninoculated controls. When mice were sacrificed at 2 days after STEC inoculation, STEC was only detected in the intestines of E. pragensis-infected mice. Colonization of STEC was also confirmed by immunohistochemistry on the surface of epithelial cells in concurrently infected/inoculated mice. Also, an overgrowth of residential E. coli was observed only in E. pragensis-infected mice. These results suggest that E. pragensis induces the suppression of intestinal peristalsis and modifies the intestinal environment to facilitate artificially introduced STEC colonization and multiplication, in addition to residential E. coli overgrowth.


Assuntos
Coccidiose/complicações , Eimeria/fisiologia , Infecções por Escherichia coli/complicações , Intestinos/microbiologia , Intestinos/parasitologia , Escherichia coli Shiga Toxigênica/fisiologia , Animais , Infecções por Escherichia coli/microbiologia , Motilidade Gastrointestinal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Escherichia coli Shiga Toxigênica/crescimento & desenvolvimento
16.
J. venom. anim. toxins incl. trop. dis ; 28: e20210099, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1375813

RESUMO

Background: The intrinsic sensitivity limitations of basic parasitological methods, along with the particular biological characteristics of parasites, make these methods ineffective to differentiate morphologically indistinguishable species. Molecular detection and characterization techniques could be used to overcome these problems. The purpose of this work was to standardize molecular polymerase chain reaction (PCR) techniques, described in the literature, for the detection and molecular characterization of intestinal protozoa and other pathogens in humans. Methods: DNA was extracted from human or animal feces, previously washed or cultured in Boeck Drbohlav's Modified Medium. DNA extraction was performed with Machery-Nagel extraction kits. The standardization of the PCR, nested-PCR or RFLP techniques was carried out according to the literature. For each molecular technique performed, the sensitivity of the test was determined based on the minimun quantity required of DNA (sensitivity A) and the minimum quantity of life forms that the test detected (sensitivity B). Results: Sensitivity A was 10 fg for G. duodenalis, 12.5 pg for Entamoeba histolytica or Entamoeba dispar, 50 fg for Cryptosporidium spp., 225 pg for Cyclospora spp. and 800 fg or 8 fg for Blastocystis spp. after performing a 1780 bp PCR or 310 bp nested PCR, respectively. The sensitivity B was 100 cysts for G. duodenalis, 500 cysts for E. histolytica or E. dispar, 1000 oocysts for Cyclospora spp. and 3600 or four vegetatives forms for PCR or nested PCR of Blastocystis spp., respectively. Conclusions: The molecular detection of protozoa and chromist was achieved and the molecular characterization allowed the genotyping of some of the parasites such as Giardia duodenalis, Cryptosporidium spp., and Blastocystis spp. This study summarizes the molecular techniques for epidemiological studies in humans and animals, and helps in the investigation of their transmission sources in countries where intestinal parasites are a public health problem.(AU)


Assuntos
Humanos , Animais , Reação em Cadeia da Polimerase/normas , Enteropatias Parasitárias/diagnóstico , Intestinos/parasitologia , Polimorfismo de Fragmento de Restrição , Estudos Epidemiológicos , Giardia lamblia , Blastocystis , Cryptosporidium
17.
Sci Rep ; 11(1): 23884, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903840

RESUMO

Chagas disease is a neglected tropical disease caused by Trypanosoma cruzi parasite with an estimated 70 million people at risk. Traditionally, parasite presence in triatomine vectors is detected through optical microscopy which can be low in sensitivity or molecular techniques which can be costly in endemic countries. The aim of this study was to evaluate the ability of a reagent-free technique, the Near Infrared Spectroscopy (NIRS) for rapid and non-invasive detection of T. cruzi in Triatoma infestans body parts and in wet/dry excreta samples of the insect. NIRS was 100% accurate for predicting the presence of T. cruzi infection Dm28c strain (TcI) in either the midgut or the rectum and models developed from either body part could predict infection in the other part. Models developed to predict infection in excreta samples were 100% accurate for predicting infection in both wet and dry samples. However, models developed using dry excreta could not predict infection in wet samples and vice versa. This is the first study to report on the potential application of NIRS for rapid and non-invasive detection of T. cruzi infection in T. infestans in the laboratory. Future work should demonstrate the capacity of NIRS to detect T. cruzi in triatomines originating from the field.


Assuntos
Insetos Vetores/parasitologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triatoma/parasitologia , Trypanosoma cruzi/patogenicidade , Animais , Fezes/parasitologia , Intestinos/parasitologia , Limite de Detecção , Espectroscopia de Luz Próxima ao Infravermelho/normas , Trypanosoma cruzi/isolamento & purificação
18.
Nat Commun ; 12(1): 6729, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795270

RESUMO

Supplementation with micronutrients, including vitamins, iron and zinc, is a key strategy to alleviate child malnutrition. However, association of gastrointestinal disorders with iron has led to ongoing debate over their administration. To better understand their impact on gut microbiota, we analyse the bacterial, protozoal, fungal and helminth communities of stool samples collected from a subset of 80 children at 12 and 24 months of age, previously enrolled into a large cluster randomized controlled trial of micronutrient supplementation in Pakistan (ClinicalTrials.gov identifier NCT00705445). We show that while bacterial diversity is reduced in supplemented children, vitamins and iron (as well as residence in a rural setting) may promote colonization with distinct protozoa and mucormycetes, whereas the addition of zinc appears to ameliorate this effect. We suggest that the risks and benefits of micronutrient interventions may depend on eukaryotic communities, potentially exacerbated by exposure to a rural setting. Larger studies are needed to evaluate the clinical significance of these findings and their impact on health outcomes.


Assuntos
Suplementos Nutricionais , Intestinos/efeitos dos fármacos , Micronutrientes/administração & dosagem , Micobioma/efeitos dos fármacos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Pré-Escolar , Feminino , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , Humanos , Lactente , Intestinos/microbiologia , Intestinos/parasitologia , Ferro/administração & dosagem , Masculino , Micobioma/genética , Parasitos/classificação , Parasitos/efeitos dos fármacos , Parasitos/genética , Filogenia , Estudos Prospectivos , Vitaminas/administração & dosagem , Zinco/administração & dosagem
19.
PLoS Negl Trop Dis ; 15(10): e0009866, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34644290

RESUMO

Extracellular vesicles (EVs) are protein-loaded nano-scaled particles that are extracellularly released by eukaryotes and prokaryotes. Parasite's EVs manipulate the immune system, making them probable next-generation vaccines. Schistosomal EVs carry different proteins of promising immunizing potentials. For evaluating the immune-protective role of Schistosoma mansoni (S. mansoni) egg-derived EVs against murine schistosomiasis, EVs were isolated from cultured S. mansoni eggs by progressive sequential cooling ultra-centrifugation technique. Isolated EVs were structurally identified using transmission electron microscope and their protein was quantified by Lowry's technique. Experimental mice were subcutaneously immunized with three doses of 20 µg EVs (with or without alum adjuvant); every two weeks, then were challenged with S. mansoni cercariae two weeks after the last immunizing dose. Six weeks post infection, mice were sacrificed for vaccine candidate assessment. EVs protective efficacy was evaluated through parasitological, histopathological, and immunological parameters. Results showed significant reduction of tegumentally deranged adult worms, hepatic and intestinal egg counts reduction by 46.58%, 93.14% and 93.17% respectively, accompanied by remarkable amelioration of sizes, numbers and histopathology of hepatic granulomata mediated by high interferon gamma (IFN γ) and antibody level. Using sera from vaccinated mice, the molecular weight of EVs' protein components targeted by the antibody produced was recognized by western immunoblot. Results revealed two bands of ~ 14 KDa and ~ 21 KDa, proving that EVs are able to stimulate specific antibodies response. In conclusion, the present study highlighted the role of S. mansoni-egg derived EVs as a potential vaccine candidate against murine schistosomiasis mansoni.


Assuntos
Vesículas Extracelulares/imunologia , Óvulo/imunologia , Schistosoma mansoni/imunologia , Vacinas/imunologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Vesículas Extracelulares/genética , Feminino , Humanos , Imunização , Intestinos/imunologia , Intestinos/parasitologia , Masculino , Camundongos , Contagem de Ovos de Parasitas , Schistosoma mansoni/genética , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/prevenção & controle , Vacinas/administração & dosagem
20.
Nature ; 599(7883): 125-130, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34671159

RESUMO

Tissue maintenance and repair depend on the integrated activity of multiple cell types1. Whereas the contributions of epithelial2,3, immune4,5 and stromal cells6,7 in intestinal tissue integrity are well understood, the role of intrinsic neuroglia networks remains largely unknown. Here we uncover important roles of enteric glial cells (EGCs) in intestinal homeostasis, immunity and tissue repair. We demonstrate that infection of mice with Heligmosomoides polygyrus leads to enteric gliosis and the upregulation of an interferon gamma (IFNγ) gene signature. IFNγ-dependent gene modules were also induced in EGCs from patients with inflammatory bowel disease8. Single-cell transcriptomics analysis of the tunica muscularis showed that glia-specific abrogation of IFNγ signalling leads to tissue-wide activation of pro-inflammatory transcriptional programs. Furthermore, disruption of the IFNγ-EGC signalling axis enhanced the inflammatory and granulomatous response of the tunica muscularis to helminths. Mechanistically, we show that the upregulation of Cxcl10 is an early immediate response of EGCs to IFNγ signalling and provide evidence that this chemokine and the downstream amplification of IFNγ signalling in the tunica muscularis are required for a measured inflammatory response to helminths and resolution of the granulomatous pathology. Our study demonstrates that IFNγ signalling in enteric glia is central to intestinal homeostasis and reveals critical roles of the IFNγ-EGC-CXCL10 axis in immune response and tissue repair after infectious challenge.


Assuntos
Homeostase , Intestinos/imunologia , Intestinos/fisiologia , Neuroglia/imunologia , Neuroglia/fisiologia , Regeneração , Túnica Adventícia/imunologia , Túnica Adventícia/parasitologia , Animais , Quimiocina CXCL10/imunologia , Duodeno/imunologia , Duodeno/parasitologia , Duodeno/patologia , Duodeno/fisiologia , Feminino , Gliose , Homeostase/imunologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Interferon gama/imunologia , Intestinos/parasitologia , Intestinos/patologia , Masculino , Camundongos , Nematospiroides dubius/imunologia , Nematospiroides dubius/patogenicidade , Transdução de Sinais/imunologia , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Infecções por Strongylida/patologia
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