Search results for "HELMINTH"
showing 10 items of 363 documents
Evaluation of a rapid immunochromatographic test for the detection of low burden Dirofilaria immitis (heartworm) in dogs and cats
2017
The performance of a rapid immunochromatographic test for the detection of Dirofilaria immitis antigens (Speed Diro™; BVT-Virbac, France) was assessed in 49 experimentally infected dogs and in 244 naturally infected animals; 142 dogs and 102 cats. In experimentally infected dogs, Speed Diro™ showed a sensitivity of 90.9% in dogs infected with one adult female worm and 100% in dogs infected with more than one female worm. Specificity was 100%. For naturally infected dogs, the Knott test and PetChek® HTWM PF served as reference methods for microfilaremia and antigenemia, respectively. All microfilaemic dogs (55/142) were positive with Speed Diro™. Importantly, none of the 21 dogs infected wit…
Helminths, hosts, and their microbiota: new avenues for managing gastrointestinal helminthiases in ruminants
2020
Evidence is emerging of complex interactions occurring between gastrointestinal (GI) parasites of ruminants and the resident gut flora, with likely implications for the pathophysiology of worm infection and disease. Similarly, recent data point toward the occurrence of a GI nematode (GIN)-specific microbiota, with potential roles in worm fundamental physiology and reproduction. Parasite-microbiota relationships might represent potential targets for the development of novel parasiticides.In this article, we review current knowledge of the role(s) that host- and helminth-associated microbiota play in ruminant host-parasite relationships, and outline potential avenues for the control of GIN of…
Extracellular non-coding RNA signatures of the metacestode stage of Echinococcus multilocularis
2020
Extracellular RNAs (ex-RNAs) are secreted by cells through different means that may involve association with proteins, lipoproteins or extracellular vesicles (EV). In the context of parasitism, ex-RNAs represent new and exciting communication intermediaries with promising potential as novel biomarkers. In the last years, it was shown that helminth parasites secrete ex-RNAs, however, most work mainly focused on RNA secretion mediated by EV. Ex-RNA study is of special interest in those helminth infections that still lack biomarkers for early and/or follow-up diagnosis, such as echinococcosis, a neglected zoonotic disease caused by cestodes of the genus Echinococcus. In this work, we have char…
A clustering package for nucleotide sequences using Laplacian Eigenmaps and Gaussian Mixture Model.
2018
International audience; In this article, a new Python package for nucleotide sequences clustering is proposed. This package, freely available on-line, implements a Laplacian eigenmap embedding and a Gaussian Mixture Model for DNA clustering. It takes nucleotide sequences as input, and produces the optimal number of clusters along with a relevant visualization. Despite the fact that we did not optimise the computational speed, our method still performs reasonably well in practice. Our focus was mainly on data analytics and accuracy and as a result, our approach outperforms the state of the art, even in the case of divergent sequences. Furthermore, an a priori knowledge on the number of clust…
Anisakis sensitization in different population groups and public health impact. A systematic review
2018
Anisakis simplex spp. sensitization rates have increased worldwide, with a significant impact on health-care systems. To date, no clear-cut diagnostic criteria and laboratory algorithm have been established, so anisakiasis still represents an under-reported health problem whose clinical manifestations, when present, mimic the much more common allergic and digestive disorders. Aim of the study was to systematically review the available literature on the prevalence of sensitization against Anisakis in the general population and in specific population groups, taking into account the impact of the different available diagnostic techniques on the epidemiological data. Following the Preferred Rep…
Cestode parasites release extracellular vesicles with microRNAs and immunodiagnostic protein cargo.
2017
Intercellular communication is crucial in multiple aspects of cell biology. This interaction can be mediated by several mechanisms including extracellular vesicle (EV) transfer. EV secretion by parasites has been reported in protozoans, trematodes and nematodes. Here we report that this mechanism is present in three different species of cestodes, Taenia crassiceps, Mesocestoides corti and Echinococcus multilocularis. To confirm this we determined, in vitro, the presence of EVs in culture supernatants by transmission electron microscopy. Interestingly, while T. crassiceps and M. corti metacestodes secrete membranous structures into the culture media, similar vesicles were observed in the int…
Morphological and molecular characterization of Paragonimus caliensis Little, 1968 (Trematoda: Paragonimidae) from Medellin and Pichinde, Colombia
2018
Paragonimiasis is a subacute to chronic inflammatory granulomatous lung disease caused by the genus Paragonimus. In Latin America Paragonimus mexicanus Miyazaki & Ishii, 1968 is the only confirmed species to cause human infections. Paragonimus caliensis Little, 1968 is an uncommon species often regarded as a synonym of P. mexicanus. Recently, the study of two types of Paragonimus metacercariae from Costa Rica has provided new molecular and morphological evidence that P. caliensis is a separate species from P. mexicanus. In the present study, molecular, morphological and phylogenetic tools have been used to characterize two populations of Paragonimus located at west of Medellin, Antioquia an…
Fasciola spp: Mapping of the MF6 epitope and antigenic analysis of the MF6p/HDM family of heme-binding proteins
2017
MF6p/FhHDM-1 is a small cationic heme-binding protein which is recognized by the monoclonal antibody (mAb) MF6, and abundantly present in parenchymal cells and secreted antigens of Fasciola hepatica. Orthologs of this protein (MF6p/HDMs) also exist in other causal agents of important foodborne trematodiasis, such as Clonorchis sinensis, Opisthorchis viverrini and Paragonimus westermani. Considering that MF6p/FhHDM-1 is relevant for heme homeostasis in Fasciola and was reported to have immunomodulatory properties, this protein is expected to be a useful target for vaccination. Thus, in this study we mapped the epitope recognized by mAb MF6 and evaluated its antigenicity in sheep. The sequenc…
Potential Influence of Helminth Molecules on COVID-19 Pathology
2020
In recent months, the parasitology research community has been tasked with investigation of the influence of parasite coinfection on coronavirus disease 2019 (COVID-19) outcomes. Herein, we share our approach to analyze the effect of the trematode Fasciola hepatica as a modulator of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and of COVID-19 pathology.
Life history adjustments to intestinal inflammation in a gut nematode.
2017
ABSTRACT Many parasitic nematodes establish chronic infections. This implies a finely tuned interaction with the host immune response in order to avoid infection clearance. Although a number of immune interference mechanisms have been described in nematodes, how parasites adapt to the immune environment provided by their hosts remains largely unexplored. Here, we used the gastrointestinal nematode Heligmosomoides polygyrus to investigate the plasticity of life history traits and immunomodulatory mechanisms in response to intestinal inflammation. We adopted an experimental model of induced colitis and exposed worms to intestinal inflammation at two different developmental stages (larvae and …