| 1. |
- Björkman, Anne, 1981, et al.
(författare)
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Plant functional trait change across a warming tundra biome
- 2018
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 562:7725, s. 57-62
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Tidskriftsartikel (refereegranskat)abstract
- The tundra is warming more rapidly than any other biome on Earth, and the potential ramifications are far-reaching because of global feedback effects between vegetation and climate. A better understanding of how environmental factors shape plant structure and function is crucial for predicting the consequences of environmental change for ecosystem functioning. Here we explore the biome-wide relationships between temperature, moisture and seven key plant functional traits both across space and over three decades of warming at 117 tundra locations. Spatial temperature–trait relationships were generally strong but soil moisture had a marked influence on the strength and direction of these relationships, highlighting the potentially important influence of changes in water availability on future trait shifts in tundra plant communities. Community height increased with warming across all sites over the past three decades, but other traits lagged far behind predicted rates of change. Our findings highlight the challenge of using space-for-time substitution to predict the functional consequences of future warming and suggest that functions that are tied closely to plant height will experience the most rapid change. They also reveal the strength with which environmental factors shape biotic communities at the coldest extremes of the planet and will help to improve projections of functional changes in tundra ecosystems with climate warming.
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| 2. |
- Björkman, Anne, 1981, et al.
(författare)
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Tundra Trait Team: A database of plant traits spanning the tundra biome
- 2018
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Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 27:12, s. 1402-1411
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 The Authors Global Ecology and Biogeography Published by John Wiley & Sons Ltd Motivation: The Tundra Trait Team (TTT) database includes field-based measurements of key traits related to plant form and function at multiple sites across the tundra biome. This dataset can be used to address theoretical questions about plant strategy and trade-offs, trait–environment relationships and environmental filtering, and trait variation across spatial scales, to validate satellite data, and to inform Earth system model parameters. Main types of variable contained: The database contains 91,970 measurements of 18 plant traits. The most frequently measured traits (>1,000 observations each) include plant height, leaf area, specific leaf area, leaf fresh and dry mass, leaf dry matter content, leaf nitrogen, carbon and phosphorus content, leaf C:N and N:P, seed mass, and stem specific density. Spatial location and grain: Measurements were collected in tundra habitats in both the Northern and Southern Hemispheres, including Arctic sites in Alaska, Canada, Greenland, Fennoscandia and Siberia, alpine sites in the European Alps, Colorado Rockies, Caucasus, Ural Mountains, Pyrenees, Australian Alps, and Central Otago Mountains (New Zealand), and sub-Antarctic Marion Island. More than 99% of observations are georeferenced. Time period and grain: All data were collected between 1964 and 2018. A small number of sites have repeated trait measurements at two or more time periods. Major taxa and level of measurement: Trait measurements were made on 978 terrestrial vascular plant species growing in tundra habitats. Most observations are on individuals (86%), while the remainder represent plot or site means or maximums per species. Software format: csv file and GitHub repository with data cleaning scripts in R; contribution to TRY plant trait database (www.try-db.org) to be included in the next version release.
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| 3. |
- Andersen, Thomas, et al.
(författare)
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C-X-C Ligand 16 Is an Independent Predictor of Cardiovascular Death and Morbidity in Acute Coronary Syndromes
- 2019
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Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 39:11, s. 2402-2410
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Tidskriftsartikel (refereegranskat)abstract
- Objective:The chemokine CXCL16 (C-X-C motif ligand 16) is a scavenger receptor for OxLDL (oxidized low-density lipoproteins) and involved in inflammation at sites of atherosclerosis. This study aimed to investigate the association of CXCL16 with clinical outcome in patients with acute coronary syndrome.Approach and Results:Serial measurements of CXCL16 were performed in a subgroup of 5142 patients randomized in the PLATO trial (Platelet Inhibition and Patient Outcome). Associations between CXCL16 and a composite of cardiovascular death, spontaneous myocardial infarction or stroke, and the individual components were assessed by multivariable Cox regression analyses. The hazard ratio per 50% increase in admission levels of CXCL16 analyzed as continuous variable was 1.64 (95% CI, 1.44-1.88), P<0.0001. This association remained statistically significant after adjustment for randomized treatment, clinical variables, CRP (C-reactive protein), leukocytes, cystatin C, NT-proBNP (N-terminal pro-brain natriuretic peptide), troponin T, GDF-15 (growth differentiation factor 15), and other biomarkers; hazard ratio 1.23 (1.05-1.45), P=0.0126. The admission level of CXCL16 was independently associated with cardiovascular death (1.50 [1.17-1.92], P=0.0014) but not with ischemic events alone, in fully adjusted analyses. No statistically independent association was found between CXCL16 measured at 1 month, or change in CXCL16 from admission to 1 month, and clinical outcomes.Conclusions:In patients with acute coronary syndrome, admission level of CXCL16 is independently related to adverse clinical outcomes, mainly driven by an association to cardiovascular death. Thus, CXCL16 measurement may enhance risk stratification in patients with this condition.
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| 4. |
- Norum, Hilde M, et al.
(författare)
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Circulating delta-like Notch ligand 1 is correlated with cardiac allograft vasculopathy and suppressed in heart transplant recipients on everolimus-based immunosuppression.
- 2019
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Ingår i: American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons. - : Elsevier BV. - 1600-6143. ; 19:4, s. 1050-1060
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Tidskriftsartikel (refereegranskat)abstract
- Cardiac allograft vasculopathy (CAV) causes heart failure after heart transplantation (HTx), but its pathogenesis is incompletely understood. Notch signaling, possibly modulated by everolimus (EVR), is essential for processes involved in CAV. We hypothesized that circulating Notch ligands would be dysregulated after HTx. We studied circulating delta-like Notch ligand 1 (DLL1) and periostin (POSTN) and CAV in de novo HTx recipients (n=70) randomized to standard or EVR-based, calcineurin inhibitor-free immunosuppression and in maintenance HTx recipients (n=41). Compared to healthy controls, plasma DLL1 and POSTN were elevated in de novo (P<.01; P<.001) and maintenance HTx recipients (P<.001; P<.01). Use of EVR was associated with a treatment effect for DLL1. For de novo HTx recipients, a change in DLL1 correlated with a change in CAV at 1 (P=.021) and 3years (P=.005). In vitro, activation of T cells increased DLL1 secretion, attenuated by EVR. In vitro data suggest that also endothelial cells and vascular smooth muscle cells (VSMCs) could contribute to circulating DLL1. Immunostaining of myocardial specimens showed colocalization of DLL1 with T cells, endothelial cells, and VSMCs. Our findings suggest a role of DLL1 in CAV progression, and that the beneficial effect of EVR on CAV could reflect a suppressive effect on DLL1. Trial registration numbers-SCHEDULE trial: ClinicalTrials.gov NCT01266148; NOCTET trial: ClinicalTrials.gov NCT00377962.
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| 5. |
- Shahini, Negar, et al.
(författare)
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Increased Complement Factor B and Bb Levels Are Associated with Mortality in Patients with Severe Aortic Stenosis
- 2019
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Ingår i: Journal of Immunology. - : American Association of Immuologists. - 0022-1767 .- 1550-6606. ; 203:7, s. 1973-1980
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Tidskriftsartikel (refereegranskat)abstract
- Inflammation is involved in initiation and progression of aortic stenosis (AS). However, the role of the complement system, a crucial component of innate immunity in AS, is unclear. We hypothesized that circulating levels of complement factor B (FB), an important component of the alternative pathway, are upregulated and could predict outcome in patients with severe symptomatic AS. Therefore, plasma levels of FB, Bb, and terminal complement complex were analyzed in three cohorts of patients with severe symptomatic AS and mild-to-moderate or severe asymptomatic AS (population 1, n = 123; population 2, n = 436; population 3, n = 61) and in healthy controls by enzyme immunoassays. Compared with controls, symptomatic AS patients had significantly elevated levels of FB (2.9- and 2.8-fold increase in population 1 and 2, respectively). FB levels in symptomatic and asymptomatic AS patients were comparable (population 2 and 3), and in asymptomatic patients FB correlated inversely with valve area. FB levels in population 1 and 2 correlated with terminal complement complex levels and measures of systemic inflammation (i.e., CRP), cardiac function (i.e., NT-proBNP), and cardiac necrosis (i.e., Troponin T). High FB levels were significantly associated with mortality also after adjusting for clinical and biochemical covariates (hazard ratio 1.37; p = 0.028, population 2). Plasma levels of the Bb fragment showed a similar pattern in relation to mortality. We concluded that elevated levels of FB and Bb are associated with adverse outcome in patients with symptomatic AS. Increased levels of FB in asymptomatic patients suggest the involvement of FB from the early phase of the disease.
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| 6. |
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| 7. |
- Shahini, Negar, et al.
(författare)
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The alternative complement pathway is dysregulated in patients with chronic heart failure
- 2017
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 7, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- The complement system, an important arm of the innate immune system, is activated in heart failure (HF). We hypothesized that HF patients are characterized by an imbalance of alternative amplification loop components; including properdin and complement factor D and the alternative pathway inhibitor factor H. These components and the activation product, terminal complement complex (TCC), were measured in plasma from 188 HF patients and 67 age- and sex- matched healthy controls by enzyme immunoassay. Our main findings were: (i) Compared to controls, patients with HF had significantly increased levels of factor D and TCC, and decreased levels of properdin, particularly patients with advanced clinical disorder (i.e., NYHA functional class IV), (ii) Levels of factor D and properdin in HF patients were correlated with measures of systemic inflammation (i.e., C-reactive protein), neurohormonal deterioration (i.e., Nt-proBNP), cardiac function, and deteriorated diastolic function, (iii) Low levels of factor H and properdin were associated with adverse outcome in univariate analysis and for factor H, this was also seen in an adjusted model. Our results indicate that dysregulation of circulating components of the alternative pathway explain the increased degree of complement activation and is related to disease severity in HF patients.
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| 8. |
- Ueland, Thor, et al.
(författare)
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Admission Levels of DKK1 (Dickkopf-1) Are Associated With Future Cardiovascular Death in Patients With Acute Coronary Syndromes
- 2019
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Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 39:2, s. 294-302
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Tidskriftsartikel (refereegranskat)abstract
- Objective- The Wnt/wingless signaling antagonist DKK1 (dickkopf-1) regulates platelet-mediated inflammation and may contribute to plaque destabilization. We hypothesized that DKK1 would be associated with cardiovascular outcomes.Approach and Results- We determined DKK1 levels in serum samples obtained before randomization, at discharge, and 1 and 6 months in a subset of 5165 patients with acute coronary syndromes in the PLATO trial (Platelet Inhibition and Patient Outcomes; NCT00391872). The median (interquartile range) DKK1 concentrations were 0.61 (0.20-1.27) ng/mL at baseline and increased during follow-up. The hazard ratio (95% CIs) for the composite end point (cardiovascular death, nonprocedural spontaneous myocardial infarction, or stroke) during 1 year of follow-up, per 50% increase in baseline DKK1 concentration, was 1.06 (1.02-1.10), P=0.0011, and remained significant in fully adjusted analysis with 14 conventional clinical and demographic and 6 biochemical variables, including NT-proBNP (N-terminal pro-B-type natriuretic peptide), hs-TnT (high-sensitivity troponin T), and GDF-15 (growth differentiation factor 15; 1.05 [1.00-1.09]; P=0.028). This association was mainly driven by the association with cardiovascular death, where a gradual increase in event rates was observed with increasing quartiles of DKK1 (2.7%, 3.0%, 4.3%, and 5.0%) and remained significant and unmodified in fully adjusted analysis (hazard ratio, 1.10 [1.04-1.17]; P=0.002). Change in DKK1 and levels at 1 month were unrelated to outcomes. A modifying effect of ticagrelor on DKK1 discharge levels was observed but not associated with prognosis.Conclusions- In patients with acute coronary syndromes treated with dual antiplatelet treatment, admission DKK1 levels were independently associated with a composite of cardiovascular death, myocardial infarction, or stroke and with cardiovascular death alone.
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| 9. |
- Ueland, Thor, et al.
(författare)
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Osteoprotegerin Is Associated With Major Bleeding But Not With Cardiovascular Outcomes in Patients With Acute Coronary Syndromes : Insights From the PLATO (Platelet Inhibition and Patient Outcomes) Trial
- 2018
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Ingår i: Journal of the American Heart Association. - : WILEY. - 2047-9980. ; 7:2
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Tidskriftsartikel (refereegranskat)abstract
- Background-Elevated levels of osteoprotegerin, a secreted tumor necrosis factor-related molecule, might be associated with adverse outcomes in patients with coronary artery disease. We measured plasma osteoprotegerin concentrations on hospital admission, at discharge, and at 1 and 6months after discharge in a predefined subset (n=5135) of patients with acute coronary syndromes in the PLATO (Platelet Inhibition and Patient Outcomes) trial. Methods and Results-The associations between osteoprotegerin and the composite end point of cardiovascular death, nonprocedural spontaneous myocardial infarction or stroke, and non-coronary artery bypass grafting major bleeding during 1year of follow-up were assessed by Cox proportional hazards models. Event rates of the composite end point per increasing quartile groups at baseline were 5.2%, 7.5%, 9.2%, and 11.9%. A 50% increase in osteoprotegerin level was associated with a hazard ratio (HR) of 1.31 (95% confidence interval [CI], 1.21-1.42) for the composite end point but was not significant in adjusted analysis (ie, clinical characteristics and levels of C-reactive protein, troponin T, NT-proBNP [N-terminal pro-B-type natriuretic peptide], and growth differentiation factor-15). The corresponding rates of non-coronary artery bypass grafting major bleeding were 2.4%, 2.2%, 3.8%, and 7.2%, with an unadjusted HR of 1.52 (95% CI, 1.36-1.69), and a fully adjusted HR of 1.26 (95% CI, 1.09-1.46). The multivariable association between the osteoprotegerin concentrations and the primary end point after 1month resulted in an HR of 1.09 (95% CI, 0.89-1.33); for major bleeding after 1month, the HR was 1.33 (95% CI, 0.91-1.96). Conclusions-In patients with acute coronary syndrome treated with dual antiplatelet therapy, osteoprotegerin was an independent marker of major bleeding but not of ischemic cardiovascular events. Thus, high osteoprotegerin levels may be useful in increasing awareness of increased bleeding risk in patients with acute coronary syndrome receiving antithrombotic therapy.
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| 10. |
- Wallentin, Lars, et al.
(författare)
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Activated Leukocyte Cell Adhesion Molecule (ALCAM) And Outcomes In Acute Coronary Syndromes : A Plato Biomarker Substudy
- 2015
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Ingår i: Journal of the American College of Cardiology. - Uppsala Univ, Dept Med Sci, Cardiol, Uppsala, Sweden. Uppsala Univ, Uppsala Clin Res Ctr, Uppsala, Sweden.. - 0735-1097 .- 1558-3597. ; 65:10, s. A231-A231
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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