Search results for "DUB"
showing 10 items of 151 documents
Aging parasites produce offspring with poor fitness prospects.
2017
Senescing individuals have poor survival prospects and low fecundity. They can also produce offspring with reduced survival and reproductive success. We tested the effect of parental age on the performance of descendants in the nematode Heligmosomoides polygyrus , an intestinal parasite of rodents. We found that offspring of senescing worms had reduced within-host survival and reduced egg shedding over the first month post-infection compared with offspring produced by young parents. These results suggest that declining offspring quality is a component of senescence in parasitic nematodes and might have evolutionary consequences for the optimal schedule of age-dependent investment into repr…
Reaction norms of host immunity, host fitness and parasite performance in a mouse - intestinal nematode interaction.
2016
8 pages; International audience; The outcome of the encounter between a host and a parasite depends on the synergistic effects of the genetics of the two partners and the environment (sensulato) where the interaction takes place. Reaction norms can depict how host and parasite traits vary across environmental ranges for different genotypes. Here, we performed a large scale experiment where three strains of laboratory mice (SJL, BALB/c and CBA) were infected with four doses of the intestinal nematode Heligmosomoides polygyrus. An increasing infective dose can be considered as a proxy for the environment-dependent risk incontracting the infection. We looked at the fitness traits of hosts and …
Plastic and micro-evolutionary responses of a nematode to the host immune environment
2017
9 pages; International audience; Parasitic organisms have to cope with the defences deployed by their hosts and this can be achieved adopting immune evasion strategies or optimal life history traits according to the prevailing pattern of immune-mediated mortality. Parasites often encounter variable immune environments both within and between hosts, promoting the evolution of plastic strategies instead of fixed responses. Here, we explored the plasticity and micro-evolutionary responses of immunomodulatory mechanisms and life history traits to the immune environment provided by the host, using the parasitic nematode Heligmosomoides polygyrus. To test if the parasite responds plastically to t…
Microevolutionary response of a gut nematode to intestinal inflammation.
2017
7 pages; International audience; Parasitic helminths interfere with the immune response of their hosts to establish long-lasting, chronic infections. While favorable to the parasite, the capacity to dampen the immune response can also provide a benefit to the host in terms of reduced risk of immune disorders and immunopathology. The immunomodulatory role of nematodes has been exploited in clinical trials to treat a number of inflammatory and immune diseases. However, how parasites adapt to an inflammatory environment remains a poorly explored question. Here, we conducted a serial passage experiment where the gut nematode Heligmosomoides polygyrus was maintained for nine generations in mice …
Disentangling the effect of host genetics and gut microbiota on resistance to an intestinal parasite
2019
11 pages; International audience; Resistance to infection is a multifactorial trait, and recent work has suggested that the gut microbiota can also contribute to resistance. Here, we performed a fecal microbiota transplant to disentangle the contribution of the gut microbiota and host genetics as drivers of resistance to the intestinal nematode Heligmosomoides polygyrus. We transplanted the microbiota of a strain of mice (SJL), resistant to H. polygyrus, into a susceptible strain (CBA) and vice-versa. We predicted that if the microbiota shapes resistance to H. polygyrus, the FMT should reverse the pattern of resistance between the two host strains. The two host strains had different microbi…
Early life infection and host senescence
2018
IF 3.224 (2017); International audience; Advanced age is often associated with a chronic inflammatory status and inflammatory diseases. It has been suggested that exposure to infectious agents that stimulate the inflammatory response at early ages might have carry over effects in terms of accelerated senescence and increased mortality at late ages. However, not all pathogens and parasites have pro-inflammatory effects. In particular, parasitic nematodes have been shown to dampen the inflammatory response and to prevent or alleviate the symptoms of inflammatory diseases. We, therefore, tentatively predicted that early infection with a parasite that has anti-inflammatory properties might post…
Subtitling and dubbing as teaching resources for learning English as a foreign language using Clipflair software
2020
[EN] The research validity of using clips as audiovisual material to teach a foreign language has been demonstrated by many scholars. At the same time, the combination of this material with two modalities of audiovisual translation (AVT) - subtitling and dubbing- is worth exploring. The aim of this study is to present the effectiveness of subtitling and dubbing activities as tools for teaching English as a foreign language. In order to do so, a number of participants from the University of Valencia (Spain) whose level of English was B2/B2+ were engaged in a combination of subtitling and dubbing activities. I devised a series of tasks based on a two-minute subtitled video-clip, designed to i…
Reflections about the authentic document in "post mortem" fecundation
2018
[EN] The legislation on assisted reproduction contemplates the ¿post mortem¿ fecundation. Nevertheless, the document for the presentation of the assent raises some doubts in relation with the principle of party autonomy and the new technologies of the information and communication (ICTs). In the present work one thinks about these questions and one tries to contribute some solution of application in the Spanish legal system.
Leonīda Keirāna vēstule Ernestam Foldātam
1998
Latviešu dabaszinātnieka Leonīda Keirāna vēstule latviešu orhideju pētniekam Ernestam Foldātam, kurā viņš raksta par to, ka Daugavpils Pedagoģiskās universitātes Dabaszinātņu un matemātikas fakultātes Bioloģijas un mācīšanas metodikas katedrā 1998. gada 12. jūnijā Olga Dubrovska aizstāvēja un ieguva bakalaura grādu pedagoģijas nozarē bioloģijas mācīšanas metodikas apakšnozarē ar ļoti augstu vērtējumu par tematu "Prof. Ernesto Foldāts - latvietis, izcils Dienvidamerikas tropu floras pētnieks". Vēstulē pieminēti izmantotie informācijas avoti, cits absolvents Andrejs Balabkins, kura darbā izmantotas Ernesta Foldāta lekcijas, neliela informācija par pašu Leonīdu Keirānu. Vēstule rokrakstā uz 2 …
Identification of Candida dubliniensis among oral yeast isolates from an italian population of human immunodeficiency virus-infected (HIV +) subjects
2002
Candida dubliniensis, an emerging oral pathogen, phenotypically resembles Candida albicans so closely that it is easily misidentified as such. The aim of the present study was to evaluate the usefulness of two phenotypic methods, growth at 45 degrees C and 2,3,5-triphenyltetrazolium chloride (TTC) reduction, for confirming presumptive identification of C. dubliniensis and C. albicans by colony color on CHROMagar Candida (CAC) medium. A combination of these methods was used to establish the prevalence of oral C. dubliniensis in an Italian population of 45 human immunodeficiency virus (HIV)-infected subjects. Twenty-two samples (48.9%) were positive for yeasts on CAC medium producing a total …