Search results for "Parasite"
showing 10 items of 827 documents
Pulchrosomapulchrosoma(Trematoda: Cathaemasiidae) in Ringed kingfishers (Megaceryletorquatatorquata) from Iquitos, Peru: with inferences on life-cycl…
2007
In the winter of 2001, four Ringed kingfishers (Megaceryle torquata torquata) were imported from Iquitos, Peru for the zoological garden Faunia in Madrid. Two individuals were necropsied, and infections by the digenean trematode Pulchrosoma pulchrosoma were discovered inside granulomas located in the lung, trachea and coelomic cavity. The life cycle of this trematode species is unknown. In one case the host maintained the parasite infection for at least 5 months, which represents a relatively long prepatency period. Moreover, the body locations in the hosts may suggest that the parasite is able to actively cross the lungs from the coelomic cavity to propagate.
A new alternative in vitro method for quantification of Toxoplasma gondii infectivity.
2011
An in vitro method to determine the infectious potency of an unknown suspension of the protozoan parasite Toxoplasma gondii based on kinetics of host cells lysis was developed. Mic1-3KO a mutant strain of T. gondii RH tachyzoites was inoculated in 25-cm² flasks containing a 90% confluent monolayer of human foreskin fibroblasts. Lysis kinetics was monitored for infection ratios ranging from 1∶10⁶ to 1∶10; we defined 10⁶ tachyzoites/ml⁻¹ as the threshold value for parasite egress. Results allowed us to build a calibration curve relating the initial infection ratios to the time needed to reach 10⁶ tachyzoites/ml⁻¹. Finally, we validated the method using a known mixture of dead and live parasit…
Carotenoid trade-off between parasitic resistance and sexual display: an experimental study in the blackbird (Turdus merula).
2008
Many parasites depress the expression of the carotenoid-based colour displays of their hosts, and it has been hypothesized that animals face a trade-off in carotenoid allocation between immune functions and ‘degree of ornamentation’. While numerous correlative studies suggest that parasite infection decreases the intensity of carotenoid-based colour displays, the existence of this trade-off has never been demonstrated experimentally in a host–parasite model. In this study, we used the blackbird ( Turdus merula ) and Isospora (an intestinal parasite) to assess whether this trade-off does indeed exist. Blackbirds were supplemented with carotenoids while simultaneously being exposed to parasi…
Echinostomes as experimental models for interactions between adult parasites and vertebrate hosts.
2005
Echinostomes are intestinal trematodes that, for years, have served as experimental models in different areas of parasitology. However, the usefulness of these trematodes in experimental parasitology has been underappreciated. In this article, we examine the characteristics that make echinostomes useful models for analysis of the interactions between adult parasites and vertebrate hosts, particularly in relation to the host-related factors that determine the establishment of the parasites.
Description of Acanthocephalus anguillae balkanicus subsp. n. (Acanthocephala: Echinorhynchidae) from Proteus anguinus Laurenti (Amphibia: Proteidae)…
2019
Acanthocephalus balkanicus Batchvarov et Combes, 1974 was incompletely described from the northern crested newt, Triturus cristatus (Laurenti) (Amphibia: Salamandridae), a possible synonym of the Balkan crested newt, Triturus ivanbureschi Arntzen et Wielstra, from a pond in village of Pesnopoy, southern Bulgaria. We provide a full description of adult males and females of the same taxon from the olm, Proteus anguinus Laurenti (Amphibia: Proteidae), the only exclusively aquatic cave-dwelling vertebrate in Europe, captured in Postojna-Planina Cave System in Slovenia. Cystacanths were also collected from the cave ecomorph of Asellus aquaticus (Linnaeus) (Crustacea: Asellidae) in the same locat…
Mining parasite data using genetic programming.
2005
Genetic programming is a technique that can be used to tackle the hugely demanding data-processing problems encountered in the natural sciences. Application of genetic programming to a problem using parasites as biological tags demonstrates its potential for developing explanatory models using data that are both complex and noisy.
Molecular cloning and characterization ofEchinostoma caproniheat shock protein-70 and differential expression in the parasite derived from low- and h…
2008
SUMMARYWe cloned and expressedEchinostoma caproniHSP70 inEscherichia coli. This molecule presents an open reading frame (ORF) of 655 amino acids, and a theoretical molecular weight of 71 kDa.E. caproniHSP70 protein showed a high homology to other helminth molecules, major differences being located in the C-terminal region of the molecule, with a hydrophobic portion. Studies of protein and messenger RNA (mRNA) expression revealed a distinct pattern, depending on the host (low- or high-compatible). Specific polyclonal antisera raised against the recombinant protein expressed inEscherichia colidemonstrated its selective presence in excretory/secretory products (ESP) of adult parasites obtained…
Coexistence of three microsporidia parasites in populations of the freshwater amphipod Gammarus roeseli: evidence for vertical transmission and posit…
2004
We investigated the prevalence, transmission mode and fitness effects of infections by obligatory intracellular, microsporidian parasites in the freshwater amphipod Gammarus roeseli. We found three different microsporidia species in this host, all using transovarial (vertical) transmission. All three coexist at different prevalences in two host populations, but bi-infected individuals were rarely found, suggesting no (or very little) horizontal transmission. It is predicted that vertically-transmitted parasites may exhibit sex-specific virulence in their hosts, or they may have either positive or neutral effects on host fitness. All three species differed in their transmission efficiency an…
Proximate factors affecting the larval life history of Acanthocephalus lucii (Acanthocephala).
2007
The growth and eventual size of larval helminths in their intermediate hosts presumably has a variety of fitness consequences. Therefore, elucidating the proximate factors affecting parasite development within intermediate hosts should provide insight into the evolution of parasite life histories. An experimental infection that resulted in heavy intensities of an acanthocephalan (Acanthocephalus lucii) in its isopod intermediate host (Asellus aquaticus) permitted the examination of parasite developmental responses to variable levels of resource availability and intraspecific competition. Isopods were infected by exposure to egg-containing fish feces, and larval infrapopulations were monitor…
Leishmaniasis, autoimmune rheumatic disease, and anti–tumor necrosis factor therapy, Europe.
2009
We report 2 cases of leishmaniasis in patients with autoimmune rheumatic diseases in Greece. To assess trends in leishmaniasis reporting in this patient population, we searched the literature for similar reports from Europe. Reports increased during 2004–2008, especially for patients treated with anti–tumor necrosis factor agents.