Search results for "host"
showing 10 items of 1982 documents
Oxysterol mixture in hypercholesterolemia-relevant proportion causes oxidative stress-dependent eryptosis.
2014
Background/Aims: Oxysterol activity on the erythrocyte (RBC) programmed cell death (eryptosis) had not been studied yet. Effects of an oxysterol mixture in hyper-cholesterolemic-relevant proportion, and of individual compounds, were investigated on RBCs from healthy humans. Methods: Membrane phosphatidylserine (PS) externalization, calcium entry, ROS production, amino-phospholipid translocase (APLT) activity were evaluated by cytofluorimetric assays, cell volume from forward scatter. Prostaglandin PGE2 was measured by ELISA; GSH-adducts and lipoperoxides by spectrophotometry. Involvement of protein kinase C and caspase was investigated by inhibitors staurosporin, calphostin C, and Z-DEVD-FM…
Risk assessment of non-target effects of Closterocerus chamaeleon (Girault) parasitoid of the eucalypt gall maker Ophelimus maskelli (Ashmead) (Hymen…
2015
The pre-release risk assessment, a recommended practice in biological control programmes, was carried out before introducing Closterocerus chamaeleon (Girault), a eulophid parasitoid of the eucalypt gall maker Ophelimus maskelli (Ashmead) (Hymenoptera, Eulophidae), in Sicily, Italy. We evaluated its host specificity in laboratory small arena no-choice tests on six non-target hosts, using O. maskelli as a control species. The non-target species fit with at least one of the following criteria: a) common geographical origin; b) ecological or behavioural affinities with the target host; c) concealed habit of the preimaginal stages; d) taxonomic affinity; e) taxonomic affinity with hosts of cong…
The Conceptualisation and Measurement of Mega Sport Event Legacies
2007
This paper focuses on the legacy of mega sport events. First, the concept of legacy is defined before the problems of measuring and forecasting legacy are discussed. Benchmarking and the use of macro data do not correctly reveal legacy. Hence a bottom-up approach is introduced which identifies the event legacy by evaluation of ‘soft’ and ‘hard’ event-related changes in a host city. These changes are defined as ‘event-structures’ (infrastructure, knowledge, image, emotions, networks, culture). Many of them change the quality of location factors of the host city in the long-term. The benefits/costs through the transformation of the host city are the legacy of a mega sport event. Here a partic…
PACo: a novel procrustes application to cophylogenetic analysis.
2013
We present Procrustean Approach to Cophylogeny (PACo), a novel statistical tool to test for congruence between phylogenetic trees, or between phylogenetic distance matrices of associated taxa. Unlike previous tests, PACo evaluates the dependence of one phylogeny upon the other. This makes it especially appropriate to test the classical coevolutionary model that assumes that parasites that spend part of their life in or on their hosts track the phylogeny of their hosts. The new method does not require fully resolved phylogenies and allows for multiple host-parasite associations. PACo produces a Procrustes superimposition plot enabling a graphical assessment of the fit of the parasite phyloge…
Towards the fluorogenic detection of peroxide explosives through host-guest chemistry
2018
[EN] Two dansyl-modified beta-cyclodextrin derivatives (1 and 2) have been synthesized as host-guest sensory systems for the direct fluorescent detection of the peroxide explosives diacetone diperoxide (DADP) and triacetone triperoxide (TATP) in aqueous media. The sensing is based on the displacement of the dansyl moiety from the cavity of the cyclodextrin by the peroxide guest resulting in a decrease of the intensity of the fluorescence of the dye. Both systems showed similar fluorescent responses and were more sensitive towards TATP than DADP.
Did the ancient crenarchaeal viruses from the dawn of life survive exceptionally well the eons of meteorite bombardment?
2009
The viruses of Crenarchaeota are unexpectedly diverse in their morphologies, and most have no, or few, genes related to bacterial, eukaryal, euryarchaeal, or other crenarchaeal viruses. Though several different virus morphotypes have been discovered in enrichment cultures of microbial communities collected from geothermally heated environments around the world, the origins of such differences are unknown. We present a model that combines consideration of Earth's geological history, the early emergence of hyperthermophiles, and the early formation of viruses from primordial genes with the intent to explain this vast diversity of crenarchaeal viruses. Several meteorite- or flood basalt-induce…
Eye fluke infection and lens size reduction in fish: a quantitative analysis.
2008
Parasites have a variety of harmful effects on their hosts, some of which may be overlapping or complementary and thus easily overlooked but which are still important for the overall severity of infection. We investigated the effect of Diplostomum sp. eye fluke infection on the size of the eye lens in a range of wild and farmed fish species and those exposed to controlled parasite infection. We found that asymmetry in intensity of infection between the right and left lens of an individual fish affected lens size such that the lens with the higher intensity of infection was smaller. Interestingly, however, this was observed only in 3 of the 10 species studied (whitefish, smelt and sea trout)…
Learning how to live together: genomic insights into prokaryote–animal symbioses
2008
Our understanding of prokaryote-eukaryote symbioses as a source of evolutionary innovation has been rapidly increased by the advent of genomics, which has made possible the biological study of uncultivable endosymbionts. Genomics is allowing the dissection of the evolutionary process that starts with host invasion then progresses from facultative to obligate symbiosis and ends with replacement by, or coexistence with, new symbionts. Moreover, genomics has provided important clues on the mechanisms driving the genome-reduction process, the functions that are retained by the endosymbionts, the role of the host, and the factors that might determine whether the association will become parasitic…
Evolution of Prokaryote-Animal Symbiosis from a Genomics Perspective
2010
Symbioses involving prokaryotes living in close relationship with eukaryotic cells have been widely studied from a genomic perspective, especially in the case of insects. In the process toward host accommodation, symbionts experience major genetic and phenotypic changes that can be detected in comparison with free-living relatives. But, as expected, several scenarios allowed the evolution of symbiotic associations, from the first stages of free-living bacteria, through secondary and facultative symbiosis, towards the final point of obligate primary endosymbiosis. Particular relevance has the association formed by the coexistence of several symbionts into a given host. A summary of findings …
Do they stay or go? Analysis of international students in Finland
2020
The increase in international student mobility raises questions of how many international students choose to stay in their host country and the reasons why some stay and others leave. This study ex...