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Pied flycatcher melanin oxidative stress data
No full textThe file contains two data sheets "chicks" and "males". Measurements of SOD, CAT, GP, GSHratio, GSHtotal, CARB and GST as indicators of oxidative stress are assigned to each individual. Temperature measure is an average temperature value for nestling period (day 4 to day 11) and individually assigned for each box
Data from: Sex-dependent differences in central artery hemodynamics in normal and fibulin-5 deficient mice: implications for ageing
No full textMouse models provide unique opportunities to study vascular disease, but they demand increased experimental and computational resolution. We describe a workflow for combining in vivo and in vitro biomechanical data to build mouse-specific computational models of the central vasculature including regional variations in biaxial wall stiffness, thickness and perivascular support. These fluid–solid interaction models are informed by micro-computed tomography imaging and in vivo ultrasound and pressure measurements, and include mouse-specific inflow and outflow boundary conditions. Hence, the model can capture three-dimensional unsteady flows and pulse wave characteristics. The utility of this experimental–computational approach is illustrated by comparing central artery biomechanics in adult wild-type and fibulin-5 deficient mice, a model of early vascular ageing. Findings are also examined as a function of sex. Computational results compare well with measurements and data available in the literature and suggest that pulse wave velocity, a spatially integrated measure of arterial stiffness, does not reflect well the presence of regional differences in stiffening, particularly those manifested in male versus female mice. Modelling results are also useful for comparing quantities that are difficult to measure or infer experimentally, including local pulse pressures at the renal arteries and characteristics of the peripheral vascular bed that may differ with disease
Data from: Effect of dimethyl fumarate on lymphocytes in RRMS: implications for clinical practice
No full textObjective: To assess functional changes in lymphocyte repertoire and subsequent clinical implications during delayed-release dimethyl fumarate (DMF) treatment in patients with multiple sclerosis.
Methods: Using peripheral blood from several clinical trials of DMF, immune cell subsets were quantified using flow cytometry. For some patients, lymphocyte counts were assessed after DMF discontinuation. Incidence of adverse events, including serious and opportunistic infections, was assessed.
Results: In DMF-treated patients, absolute lymphocyte counts (ALCs) demonstrated a pattern of decline followed by stabilization, which also was reflected in the global reduction in numbers of circulating functional lymphocyte subsets. The relative frequencies of circulating memory T- and B-cell populations declined and naive cells increased. No increased incidence of serious infection or malignancy was observed for patients treated with DMF, even when stratified by ALC or T-cell subset frequencies. For patients who discontinued DMF due to lymphopenia, ALCs increased after DMF discontinuation; recovery time varied by ALC level at discontinuation. T-cell subsets closely correlated with ALCs in both longitudinal and cross-sectional analyses.
Conclusions: DMF shifted the immunophenotype of circulating lymphocyte subsets. ALCs were closely correlated with CD4+ and CD8+ T-cell counts, indicating that lymphocyte subset monitoring is not required for safety vigilance. No increased risk of serious infection was observed in patients with low T-cell subset counts. Monitoring ALC remains the most effective way of identifying patients at risk of subsequently developing prolonged moderate to severe lymphopenia, a risk factor for progressive multifocal leukoencephalopathy in DMF-treated patients.
Trial registration numbers: EUDRA CT 2015-001973-42, NCT00168701, NCT00420212, NCT00451451, and NCT0083577
Data from: Size, weapons and armor as predictors of competitive outcomes in fossil and contemporary marine communities
No full textInter- and intraspecific competition are usually observed over a few generations but their patterns and consequences are seldom tractable in natural systems over longer timescales relevant to macroevolutionary change. Here, we use win-draw-lose competitive overgrowths for a marine benthic community of encrusting bryozoans that have evolved together in New Zealand for at least 2.3 million years to investigate battles for substrate space, a resource that is limiting for these colonial organisms. Using more than 6000 fossilized and contemporary battles, we explored what combination of traits – including relative zooid (module) size, weapons, armor and relative abundance –best predict battle outcomes, and if these are time-varying. In simpler models where we disregard trait-trait interactions, we find that the effects of larger zooid sizes and three-dimensional growth on battle outcomes are both positive, while that of relative abundance is negative, such that more common species are more often overgrown by less common species. When we include trait-trait and trait-time interactions in our models, we confirm that a larger zooid size is advantageous for successful overgrowth but infer that it is time-varying. In these complex models, we also detect interactions between combinations of traits, where more armored and weaponized bryozoans seem to be at a disadvantage in overgrowth battles. Our best models do perform statistically better than the null model, but we find that there is low predictability for overgrowth outcomes for our New Zealand dataset of fossil and contemporary battles, suggesting unmeasured variables and/or high stochasticity in a system that is otherwise well-characterized. A best model developed using our New Zealand data is applied to three ecologically similar systems described in previous studies to investigate its general predictive powers, with the expectation that it would perform better than null models. Surprisingly, we find that the best model developed within the New Zealand system cannot be extrapolated to other encrusting cheilostome bryozoan communities and that these three communities often even have opposite signs for trait coefficients. We conclude that there is much to learn about multi-species marine communities where biotic interactions such as competition may have long-lasting consequences for ecological and evolutionary dynamics
Data from: Limited consequences of infestation with a blood-feeding ectoparasite for the nestlings of two North Pacific seabirds
No full textThe seabird tick (Ixodes uriae) parasitizes over 60 host species in the circumpolar regions of both hemispheres, and acts as a vector for a number of potentially virulent pathogens. On Triangle Island, British Columbia, Canada, the nestlings of Cassin’s Auklet (Ptychoramphus aleuticus) and Rhinoceros Auklet (Cerorhinca monocerata) are often parasitized by seabird ticks, which may affect their growth and survival in the nest. We used a logistic growth model to interpolate between successive measures of mass (g) and wing chord (mm) for 558 Cassin’s Auklet and 344 Rhinoceros Auklet chicks over 11 years from 1996 to 2007. From the model, we estimated the asymptotic measure and the age at inflection point for each chick’s growth trajectory, and assessed the effect of tick load relative to other sources of annual and seasonal variation in growth. Most chicks (72.4% of Cassin’s Auklets, and 62.2% of Rhinoceros Auklets) hosted ≥1 ticks at least once while in the nest, and the median tick load was two in both species. The probability of hosting a tick declined strongly with chick age, such that by day 40 after hatching less than 1% hosted ticks. We found evidence that tick load had a negative effect on asymptotic weights and wing lengths of both species, but the effect was minor relative to that of other sources of annual and seasonal variation. Only at very high loads – which were rare – did ticks have effects on growth that were likely to be biologically relevant. Tick load had little effect on survival to fledging in either species.We argue that these mild effects of ticks on their hosts are consistent with a co-evolutionary process that results in intermediate virulence when parasite transmission is linked to host recovery
Data from: Natural and sexual selection on cuticular hydrocarbons: a quantitative genetic analysis
No full textWhile the reproductive benefits of sexual displays have been widely studied, we have relatively limited evidence of the fitness costs associated with most display traits. Insect cuticular hydrocarbon (CHC) profiles are sexually selected traits that also protect against desiccation. These two functions are thought to oppose each other, with investment in particular compounds believed to increase attractiveness at the expense of compounds that protect against water-loss. We investigated this potential trade-off in a quantitative genetic framework using the Australian field cricket, Teleogryllus oceanicus. Several compounds were significantly genetically correlated with either attractiveness or desiccation resistance. Of these compounds, one was negatively genetically correlated with attractiveness but positively genetically correlated with desiccation resistance. Furthermore, scoring each individual’s overall CHC profile for its level of attractiveness and desiccation resistance indicated a negative genetic correlation between these multivariate phenotypes. Together, our results provide evidence for a genetic trade-off between sexually and naturally selected functions of the CHC profile. We suggest that the production of an attractive CHC profile may be costly for males, but highlight the need for further work to support this finding experimentally. Genetic covariation between the CHC profile and attractiveness suggests that females can gain attractive sons through female choice
Data from: The specificity of Burkholderia symbionts in the social amoeba farming symbiosis: prevalence, species, genetic and phenotypic diversity
No full textThe establishment of symbioses between eukaryotic hosts and bacterial symbionts in nature is a dynamic process. The formation of such relationships depends on the life history of both partners. Bacterial symbionts of amoebae may have unique evolutionary trajectories to the symbiont lifestyle, because bacteria are typically ingested as prey. To persist after being eaten, bacteria must survive phagocytosis. In the social amoeba Dictyostelium discoideum, certain strains of Burkholderia bacteria are able to resist amoebal digestion and maintain a persistent relationship that includes carriage throughout the amoeba’s social cycle that culminates in spore formation. Some Burkholderia strains allow their host to carry other bacteria as food. This carried food is released in new environments in a trait called farming. To better understand the diversity and prevalence of Burkholderia symbionts and the traits they impart to their amoebae hosts, we first screened 700 natural isolates of D. discoideum and found 25% infected with Burkholderia. We next used a multilocus phylogenetic analysis and identified two independent transitions by Burkholderia to the symbiotic lifestyle. Finally, we tested the ability of 38 strains of Burkholderia, from D. discoideum and as well as strains isolated from other sources, for traits relevant to symbiosis in D. discoideum. Only D. discoideum native isolates belonging to the B. agricolaris, B. hayleyella, and B.bonniea species were able to form a persistent symbiotic association with D. discoideum. The Burkholderia Dictyostelium relationship provides a promising arena for further studies of the pathway to symbiosis in a unique system
Data from: Shorebirds as important vectors for plant dispersal in Europe
No full textShorebirds (Charadriiformes) undergo rapid migrations with potential for long-distance dispersal (LDD) of plants. We studied the frequency of endozoochory by shorebirds in different parts of Europe covering a broad latitudinal range and different seasons. We assessed whether plants dispersed conformed to morphological dispersal syndromes. A total of 409 excreta samples (271 faeces and 138 pellets) were collected from redshank (Tringa totanus), black-winged stilt (Himantopus himantopus), pied avocet (Recurvirostra avosetta), northern lapwing (Vanellus vanellus), Eurasian curlew (Numenius arquata) and black-tailed godwit (Limosa limosa) in south-west Spain, north-west England, southern Ireland and Iceland in 2005 and 2016, and intact seeds were extracted and identified. Godwits were sampled just before or after migratory movements between England and Iceland. The germinability of seeds was tested. Intact diaspores were recovered from all bird species and study areas, and were present in 13% of samples overall. Thirteen plant families were represented, including Charophyceae and 26 angiosperm taxa. Only four species had an "endozoochory syndrome". Four alien species were recorded. Ellenberg values classified three species as aquatic and 20 as terrestrial. Overall, 89% of seeds were from terrestrial plants, and 11% from aquatic plants. Average seed length was higher in redshank pellets than in their faeces. Six species were germinated, none of which had an endozoochory syndrome. Seeds were recorded during spring and autumn migration. Plant species recorded have broad latitudinal ranges consistent with LDD via shorebirds. Crucially, morphological syndromes do not adequately predict LDD potential, and more empirical work is required to identify which plants are dispersed by shorebirds. Incorporating endozoochory by shorebirds and other migratory waterbirds into plant distribution models would allow us to better understand the natural processes that facilitated colonization of oceanic islands, or to improve predictions of how plants will respond to climate change, or how alien species spread