42 research outputs found
Integration of palliative and supportive care in the management of advanced liver disease:development and evaluation of a prognostic screening tool and supportive care intervention
BACKGROUND AND OBJECTIVES: Patients with decompensated cirrhosis rarely receive palliative and supportive care interventions, which are routine in other life-limiting diseases. We aimed to design and evaluate a prognostic screening tool to routinely identify inpatients with decompensated cirrhosis at high risk of dying over the coming year, alongside the development of a supportive care intervention. DESIGN: Clinical notes from consecutive patients admitted as an emergency to University Hospitals Bristol with a diagnosis of cirrhosis over two distinct 90-day periods were scrutinised retrospectively for the presence or absence of five evidence-based factors associated with poor prognosis. These were analysed against their ability to predict mortality at 1 year. ‘Plan-Do-Study-Act’ (PDSA) methodology was used to incorporate poor-prognosis screening into the routine assessment of patients admitted with cirrhosis, and develop a supportive care intervention. RESULTS: 73 admissions were scrutinised (79.5% male, 63% alcohol-related liver disease, median age 54). The presence of three or more poor-prognosis criteria at admission predicted 1-year mortality with sensitivity, specificity and positive predictive value of 72.2%, 83.8% and 81.3%, respectively, and was used as a trigger for implementing the supportive care intervention. Following modification from six PDSA cycles, prognostic screening was integrated into the assessment of all patients admitted with decompensated cirrhosis, with the supportive care intervention (developed simultaneously) instigated for appropriate patients. CONCLUSIONS: We describe a model of care which identifies inpatients with cirrhosis at significant risk of dying over the coming year, and describe development of a supportive care intervention, which can be offered to suitable patients in parallel to ongoing active management
Cardiac Allograft Vasculopathy in Redo-transplants: Is it More or Less the Same the Second Time Around?
Purpose: Cardiac allograft vasculopathy (CAV) continues to hinder the long-term success of heart transplant recipients. Redo-transplantation is currently the only definitive treatment for advanced CAV. We examined whether these patients are at similar CAV-risk with the second transplantMethods: Heart recipients from 1985 to 2011 at the UTAH program were included in the study and those with CAV as an indication for redo-transplantation were identified. CAV diagnosis was made by coronary angiography and based on the 2010 ISHLT standardized nomenclature for CAV. Patient demographics, rejection history, and CAV incidence were analyzed. Results: Of the 1,169 eligible patients, 135 (11.5%) developed CAV post their first transplant; 78 cases within 10 years and 54 beyond 10 years. The mean time to CAV was 6.58 years. Of the 135 patients who developed CAV, only 21 (15.5%) ended up requiring a redo-transplant. Of the 21 retransplanted patients, 4 (19.0%) developed CAV again; 2 patients within 10 years and 2 patients beyond 10 years indicating a similar risk for CAV occurrence for first and redo-transplant. Conclusions: Our results indicate that CAV is as likely to develop in redo-transplants despite recent advances in immunosuppression and the standardized use of lipid-lowering agents. Although outcomes in redo-transplantation for the indication of CAV are favorable, efforts to better understand and minimize CAV are needed, especially in the face of scarce donor organs
The Alpine Cushion Plant Silene acaulis as Foundation Species: A Bug’s-Eye View to Facilitation and Microclimate
Alpine ecosystems are important globally with high levels of endemic and rare species. Given that they will be highly impacted by climate change, understanding biotic factors that maintain diversity is critical. Silene acaulis is a common alpine nurse plant shown to positively influence the diversity and abundance of organisms–predominantly other plant species. The hypothesis that cushion or nurse plants in general are important to multiple trophic levels has been proposed but rarely tested. Alpine arthropod diversity is also largely understudied worldwide, and the plant-arthropod interactions reported are mostly negative, that is,. herbivory. Plant and arthropod diversity and abundance were sampled on S. acaulis and at paired adjacent microsites with other non-cushion forming vegetation present on Whistler Mountain, B.C., Canada to examine the relative trophic effects of cushion plants. Plant species richness and abundance but not Simpson’s diversity index was higher on cushion microsites relative to other vegetation. Arthropod richness, abundance, and diversity were all higher on cushion microsites relative to other vegetated sites. On a microclimatic scale, S. acaulis ameliorated stressful conditions for plants and invertebrates living inside it, but the highest levels of arthropod diversity were observed on cushions with tall plant growth. Hence, alpine cushion plants can be foundation species not only for other plant species but other trophic levels, and these impacts are expressed through both direct and indirect effects associated with altered environmental conditions and localized productivity. Whilst this case study tests a limited subset of the membership of alpine animal communities, it clearly demonstrates that cushion-forming plant species are an important consideration in understanding resilience to global changes for many organisms in addition to other plants
Incorporating stand-health metrics into monitoring the effects of soil disturbance during logging on long-term forest productivity
Stand volumes at rotation are usually predicted from models based on tree growth, assuming that fast-growing trees are, and will remain, healthy. However, greater-than-expected disease occurrence on dominant trees has been reported in regenerating forests in British Columbia (BC), suggesting that forest-productivity monitoring should include health measurements. In this thesis, I assess growth and health of lodgepole pine at six installations of the Long-Term Soil Productivity (LTSP) project 15 to 20 years after soil-disturbance treatments (organic-matter removal and soil compaction). To determine treatment effects on forest health, 5400 lodgepole pine seedlings at six sites were examined for vigour and pest occurrence. Treatment effects differed among sites, suggesting that the effects of the soil-disturbance treatments on forest health are context-dependent. Larger trees generally had higher frequency of disease, contradicting the assumption that fast-growing trees are healthy. Spectral-reflectance indices of greenness calculated from aerial images correlated with ground-based measures of tree vigour and foliar disease, indicating a role for remote-sensing techniques in forest health monitoring. Topsoil-nutrient content was reduced in the forest-floor removal treatment plots, with foliar phosphorus and potassium concentrations (%) being reduced in the three older sites in the sub-boreal spruce zone. The forest-floor removal treatment was also associated with lower abundance of ectomycorrhizae, but greater abundance Suillus sp., a fungus that is associated with nitrogen-fixing diazatrophic bacteria. The main predictive growth-and-yield model used in BC (called TASS with the interface TIPSY), underestimated tree height (m) but overestimated stand density (stems/ha) at the six sites, suggesting greater-than-predicted tree mortality. Monitoring forest health in conjunction with tree growth after free-to-grow standards are met is recommended for more accurate management of long-term forest productivity.Forestry, Faculty ofGraduat
Comparing lodgepole pine growth and disease occurrence at six Long-Term Soil Productivity (LTSP) sites in British Columbia, Canada
• Recently, the assumption that stands with fast growth will have minor losses to insect and disease attack has been challenged.
• Although tree growth and health are both critical for long-term forest productivity, standardized forest-health data is rarely collected in conjunction with tree-growth data.
• Using six Long-Term Soil Productivity (LTSP) installations in British Columbia, Canada, we explore the relationships between lodgepole pine (Pinus contorta Dougl. ex Loud.) growth and disease occurrence.
• Treatment plots and random groups of 100 trees that had larger trees generally had more disease.
• These findings suggest we can no longer assume that fast growing plantations will be free of disease, which has implications for predicting future timber supply.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
A systematic review of the ecological literature on cushion plants
<p>Cushion-forming plant species are found in alpine and polar environments around the world. They modify the microclimate, thereby facilitating other plant species. Similar to the effectiveness of shrubs as a means to study facilitation in arid and semi-arid environments, we explore the potential for cushion plant species to expand the general- ity of research on this contemporary ecological interaction. A systematic review was conducted to determine the number of publications and citation frequency on relevant ecological topics whilst using shrub literature as a baseline to assess relative importance of cushions as a focal point for future ecological research. Although, there are forty times more shrub articles, mean citations per paper is comparable between cushion and shrub literature. Furthermore, the scope of ecological research topics studied us- ing cushions is broad including facilitation, competition, environmental gradients, life history, genetics, reproduction, community, ecosystem and evolution. The preliminary ecological evidence to date also strongly suggests that cushion plants can be keystone species in their ecosystems. Hence, ecological research on net interactions including facilitation and patterns of diversity can be successfully examined using cushion plants, and this is particularly timely given expectations associated with a changing climate in these regions.</p
Decomposition rates of surface and buried forest-floor material
Mechanical site preparation is assumed to reduce soil C stocks by increasing the rate at which the displaced organic material decomposes, but the evidence is equivocal. We measured rates of C loss of forest-floor material in mesh bags either placed on the surface or buried in the mineral soil at four sites in different regional climates in British Columbia. During the 3-year incubation, buried forest-floor material lost between 5% and 15% more C mass than material on the surface, with the greatest difference occurring at the site with the lowest annual precipitation. Studies of the long-term fate of buried and surface humus are needed to understand the net effects of site preparation on soil C stocks
Rarefaction curves for plant and arthropod species sampled on alpine cushion plants and paired open non-cushion plant vegetation.
<p>Mao Tau estimator and +/−1 s.e. are shown.</p
Three space ordination plots from detrended correspondence analyses for plant and arthropod richness sampled at three alpine sites on cushions and paired open non-vegetated microsites.
<p>Black points represent cushion microsites while open grey points show open microsites.</p