Search results for "host"
showing 10 items of 1982 documents
Crowding effect on adult growth, pre-patent period and egg shedding of Fasciola hepatica
2006
Fascioliasis pathogenesis depends on fluke burden. In human hyperendemic zones, individual infection intensities reach very high levels and the majority of infected subjects should be in the advanced chronic phase. The rat model offers a useful approach for pathological research in the advanced chronic period. The influence of infection intensity per rat on fluke development, pre-patent period and egg shedding (eggs/g faeces/worm) was analysed in 3 groups (I: 1–3 worms/rat; II: 4–6; III: 7–9). Ontogenetic trajectories of fluke body measures followed a logistic model. Results showed that when the burden increases, the maximum values of fluke measures decrease. The crowding effect is manifest…
Microbial Succession in the Gut: Directional Trends of Taxonomic and Functional Change in a Birth Cohort of Spanish Infants
2014
In spite of its major impact on life-long health, the process of microbial succession in the gut of infants remains poorly understood. Here, we analyze the patterns of taxonomic and functional change in the gut microbiota during the first year of life for a birth cohort of 13 infants. We detect that individual instances of gut colonization vary in the temporal dynamics of microbiota richness, diversity, and composition at both functional and taxonomic levels. Nevertheless, trends discernible in a majority of infants indicate that gut colonization occurs in two distinct phases of succession, separated by the introduction of solid foods to the diet. This change in resource availability causes…
Tetraphyllidean plerocercoids from Western Mediterranean cetaceans and other marine mammals around the world: a comprehensive morphological analysis.
2005
Tetraphyllidean plerocercoids have occasionally been reported in marine mammals, but they have rarely been described in detail, and the ecological significance of these infections is unclear. We described plerocercoids collected from the mucosa of the terminal colon and rectum, the anal crypts, and the hepatopancreatic ducts of 7 striped dolphins Stenella coeruleoalba, 1 Cuvier's beaked whale Ziphius cavirostris, and 3 Risso's dolphins Grampus griseus from the Spanish Mediterranean. We also examined undescribed plerocercoids from 3 cetacean species from the Atlantic and the Pacific. All plerocercoids had a lanceolate body, and a scolex with an apical sucker and 4 sessile monolocular bothrid…
Conflict between co-occurring manipulative parasites? An experimental study of the joint influence of two acanthocephalan parasites on the behaviour …
2000
When two parasite species are manipulators and have different definitive hosts, there is a potential for conflict between them. Selection may then exist for either avoiding hosts infected with conflicting parasites, or for hijacking, i.e. competitive processes to gain control of the intermediate host. The evidence for both phenomena depends largely on the study of the relative competitive abilities of parasites within their common intermediate host. We studied the effects of simultaneous infection by a fish acanthocephalan parasite, Pomphorhynchus laevis, and a bird acanthocephalan parasite, Polymorphus minutus, on the behaviour of their common intermediate host, the amphipod Gammarus pulex…
Dialogue and Dominance in Couple Therapy for Depression: Exploring Therapists' Responses in Creating Collaborative Moments.
2019
Previous investigations have found specific communication patterns in couples dealing with depression, specifically when depression concurs with conjugal conflicts. The presence of these patterns can reflect couples' difficulties in engaging in collaborative communication during their sessions, posing a real challenge for therapists. This exploratory study uses a dialogical approach to examine issues of dominance and type of dialogue in two couples who differed in terms of their levels of dyadic adjustment. The therapists' reactions were explored in order to detect the kinds of responses that were most effective at engendering a collaborative attitude in therapy sessions. The method used to…
Morphological and molecular characterization of tetraphyllidean merocercoids (Platyhelminthes: Cestoda) of striped dolphins (Stenella coeruleoalba) f…
2005
Two types of tetraphyllidean merocercoids, Phyllobothrium delphini and Monorygma grimaldii, are well known from most cetaceans world-wide. The role of cetaceans in the life-cycle of these merocercoids is unclear because their specific identity is as yet unknown. The problem is compounded by poor descriptions of both merocercoids. We used light and scanning electron microscopy, and histological techniques to provide a thorough description of merocercoids collected from 11 striped dolphins, Stenella coeruleoalba, from the Spanish Mediterranean. We also described, for the first time, specimens of P. delphini with immature proglottides. Our merocercoids were morphologically similar to those des…
The helminth community of the wood mouse Apodemus sylvaticus in a Mediterranean ecosystem in regeneration ten years after a wildfire.
2009
AbstractThis study was carried out 10 years after a wildfire in the Spanish Serra Calderona Natural Park, following a previous analysis comprising the first 5 years after the fire. Its primary aim was to elucidate the impact of this perturbation on the population biology of the wood mouseApodemus sylvaticus, and the repercussions on its helminth community in this regenerating Mediterranean ecosystem. Second, confirmation of the ability of the parasites to tolerate environmental stressors and the effects on their transmission strategies was sought. Five hundred and sixty-four individuals ofA. sylvaticuswere studied in a 9-year period, from the second to the tenth post-fire year: 408 mice fro…
Cardiovascular and ocular safety of α1-adrenoceptor antagonists in the treatment of male lower urinary tract symptoms
2014
α1-Adrenoceptor antagonists (α-blockers) represent first-line drug treatment for male lower urinary tract symptoms. Their adverse events (AEs) include asthenia, dizziness, nasal congestion, arterial (orthostatic) hypotension and intraoperative floppy iris syndrome (IFIS).This report focuses on cardiovascular and ocular AEs of α-blockers as related to their mechanism of action and subtype selectivity.The incidence of hypotension differs between α-blockers. It is greatest with doxazosin or terazosin, but others including tamsulosin can also lead to hypotension especially upon treatment initiation. Concomitant antihypertensive medication increases the incidence of hypotension with some α-block…
Fasciola hepatica development in the experimentally infected black rat Rattus rattus
1998
The finding of natural infection of Rattus rattus by Fasciola hepatica on Corsica has stimulated further research into the role of the black rat in the epidemiology of fascioliasis. Corsican black rats were experimentally individually infected with 20 metacercariae from cattle and murine isolates obtained from naturally infected bovines and black rats. The following results were obtained: (a) in R. rattus infected with the cattle isolate, normal adult fluke development took place and infection persisted for a long period, with emission of eggs showing embryogenic capacity; (b) the development of F. hepatica adults paralleled the ontogenetic trajectories observed in other rodent-F. hepatica …
Correlation between egg-shedding and uterus development in Fasciola hepatica human and animal isolates: applied implications
2010
The emission of Fasciola hepatica eggs in faeces is usually subject to oscillations along time in animals as well as humans. Thus, looking for alternative biological markers reflecting eggs shed per gram of faeces (epg) with lower oscillations may be useful. This study analyzes the possible relationship between liver-fluke uterus area and epg. Uterus area (UA) development of adult F. hepatica obtained at different days post infection (dpi) in a Wistar rat model with isolates obtained from cattle, sheep, pigs and humans from the endemic human fascioliasis zone of the Northern Bolivian Altiplano was analyzed and compared with the number of eggs shed per gram of faeces as obtained through the …