84 research outputs found
A prospective study of monitoring practices for metabolic disease in antipsychotic-treated community psychiatric patients
<p>Abstract</p> <p>Background</p> <p>Patients with severe mental illness are at increased risk for metabolic and cardiovascular disease. A number of recent guidelines and consensus statements recommend stringent monitoring of metabolic function in individuals receiving antipsychotic drugs.</p> <p>Methods</p> <p>We conducted a prospective cohort study of 106 community-treated psychiatric patients from across the diagnostic spectrum from the Northeast of England to investigate changes in metabolic status and monitoring practices for metabolic and cardiovascular disease. We undertook detailed anthropometric and metabolic assessment at baseline and follow-up, and examined clinical notes and hospital laboratory records to ascertain monitoring practices.</p> <p>Results</p> <p>A high prevalence of undiagnosed and untreated metabolic disease was present at baseline assessment. Mean follow-up time was 599.3 (SD ± 235.4) days. Body mass index (p < 0.005) and waist circumference (p < 0.05) had significantly increased at follow-up, as had the number of individuals who were either overweight or obese. Fifty-three per cent of individuals had hypertriglyceridemia, and 31% had hypercholesterolemia, but only 7% were receiving lipid-lowering therapy. Monitoring practices were poor. Recording of measures of adiposity occurred in 0% of individuals, and > 50% of subjects had neither blood glucose nor lipids monitored during the follow-up period.</p> <p>Conclusion</p> <p>This cohort has a high prevalence of metabolic disease and heightened cardiovascular risk. Despite the publication of a number of recommendations regarding physical health screening in this population, monitoring rates are poor, and physical health worsened during the follow-up period.</p
Changes in grassland management and linear infrastructures associated to the decline of an endangered bird population
European grassland birds are experiencing major population declines, mainly due to changes in
farmland management. We analyzed the role of habitat availability, grazing management and
linear infrastructures (roads and power lines) in explaining spatial and temporal variation in the
population density of little bustards (Tetrax tetrax) in Portugal, during a decade in which the species
population size halved. We used data from 51 areas (totaling ca. 1,50,000 ha) that were sampled
in two different periods (2003–2006 and 2016). In 2003–2006, when the species occurred at high
densities, habitat availability was the only factor affecting spatial variation in bustard density. In the
2016 survey, variation in density was explained by habitat availability and livestock management,
with reduced bird numbers in areas with higher proportions of cattle. Population declines across the
study period were steeper in areas that initially held higher densities of bustards and in areas with a
higher proportion of cattle in the total stocking rate. Areas with higher densities of power lines also
registered greater density declines, probably due to avoidance behavior and to increased mortality.
Overall, our results show little bustards are currently lacking high quality grassland habitat, whose
persistence depends on extensive grazing regimes and low linear infrastructure densitiesinfo:eu-repo/semantics/publishedVersio
Simulated nitrogen deposition affects wood decomposition by cord-forming fungi.
Anthropogenic nitrogen (N) deposition affects many natural processes, including forest litter decomposition. Saprotrophic fungi are the only organisms capable of completely decomposing lignocellulosic (woody) litter in temperate ecosystems, and therefore the responses of fungi to N deposition are critical in understanding the effects of global change on the forest carbon cycle. Plant litter decomposition under elevated N has been intensively studied, with varying results. The complexity of forest floor biota and variability in litter quality have obscured N-elevation effects on decomposers. Field experiments often utilize standardized substrates and N-levels, but few studies have controlled the decay organisms. Decomposition of beech (Fagus sylvatica) blocks inoculated with two cord-forming basidiomycete fungi, Hypholoma fasciculare and Phanerochaete velutina, was compared experimentally under realistic levels of simulated N deposition at Wytham Wood, Oxfordshire, UK. Mass loss was greater with P. velutina than with H. fasciculare, and with N treatment than in the control. Decomposition was accompanied by growth of the fungal mycelium and increasing N concentration in the remaining wood. We attribute the N effect on wood decay to the response of cord-forming wood decay fungi to N availability. Previous studies demonstrated the capacity of these fungi to scavenge and import N to decaying wood via a translocating network of mycelium. This study shows that small increases in N availability can increase wood decomposition by these organisms. Dead wood is an important carbon store and habitat. The responses of wood decomposers to anthropogenic N deposition should be considered in models of forest carbon dynamics
Continuous imaging of amino-acid translocation in intact mycelia of Phanerochaete velutina reveals rapid, pulsatile fluxes
Nitrogen translocation by woodland fungi is ecologically important, however, techniques to study long-distance amino-acid transport in mycelia currently have limited spatial and temporal resolution. We report a new continuous, noninvasive imaging technique for β-emitters that operates with submillimetre spatial resolution and a practical sampling interval of 10-60 min. • Transport of the nonmetabolized, 14C-labelled amino-acid analogue, α-aminoisobutyric acid (AIB) was imaged using a photon-counting camera as it was transported in foraging mycelium of the cord-forming woodland fungus, Phanerochaete velutina, grown over an intensifying screen in microcosms. • The maximum acropetal transport velocity of 14C-AIB to the colony margin was 50 mm h-1 (average 23 mm h-1), with a mass transfer of 4.6-51.5 pmol 14C-AIB h-1 per cord. Transport in cords had a pulsatile component with a period of 11-12 h. • Transport was significantly faster than diffusion, consistent with rapid cycling of nutrients throughout the mycelium between loading and sink regions. The increased spatial and temporal resolution of this method also revealed the rhythmic nature of transport in this fungus for the first time. © New Phytologist (2002)
Quantifying dynamic resource allocation illuminates foraging strategy in Phanerochaete velutina.
Saprotrophic woodland fungi forage for mineral nutrients and woody resources by extension of a mycelial network across the forest floor. Different species explore at different rates and establish networks with qualitatively differing architecture. However, detailed understanding of fungal foraging behaviour has been hampered by the absence of tools to quantify resource allocation and growth accurately and non-invasively. To solve this problem, we have used photon-counting scintillation imaging (PCSI) to map and quantify nutrient allocation and localised growth simultaneously in heterogeneous resource environments. We show that colonies spontaneously shift to an asymmetric growth pattern, even in the absence of added resources, often with a distinct transition between the two growth phases. However, the extent of polarisation was much more pronounced and focussed in the presence of an additional cellulose resource. In this case, there was highly localised growth, often at the expense of growth elsewhere in the colony, and marked accumulation of (14)C-AIB in the sector of the colony with the added resource. The magnitude of the response was greatest when resource was added around the time of the endogenous developmental transition. The focussed response required a metabolisable resource, as only limited changes were seen with glass fibre discs used to mimic the osmotic and thigmotropic stimuli upon resource addition. Overall the behaviour is consistent with an adaptive foraging strategy, both to exploit new resources and also to redirect subsequent foraging effort to this region, presumably with an expectation that the probability of finding additional resources is increased
Emergence of self-organised oscillatory domains in fungal mycelia.
Fungi play a central role in the nutrient cycles of boreal and temperate forests. In these biomes, the saprotrophic wood-decay fungi are the only organisms that can completely decompose woody plant litter. In particular, cord-forming basidiomycete fungi form extensive mycelial networks that scavenge scarce mineral nutrients and translocate them over long distances to exploit new food resources. Despite the importance of resource allocation, there is limited information on nutrient dynamics in these networks, particularly for nitrogen, as there is no suitable radioisotope available. We have mapped N-translocation using photon-counting scintillation imaging of the non-metabolised amino acid analogue, (14)C-aminoisobutyrate. We describe a number of novel phenomena, including rapid, preferential N-resource allocation to C-rich sinks, induction of simultaneous bi-directional N-transport, abrupt switching between different pre-existing transport routes, and emergence of locally synchronised, oscillatory phase domains. It is possible that such self-organised oscillatory behaviour is a mechanism to achieve global co-ordination in the mycelium
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