31P-NMR Metabolomics Revealed Species-Specific Use of Phosphorous in Trees of a French Guiana Rainforest.

Productivity of tropical lowland moist forests is often limited by availability and functional allocation of phosphorus (P) that drives competition among tree species and becomes a key factor in determining forestall community diversity. We used non-target 31P-NMR metabolic profiling to study the foliar P-metabolism of trees of a French Guiana rainforest. The objective was to test the hypotheses that P-use is species-specific, and that species diversity relates to species P-use and concentrations of P-containing compounds, including inorganic phosphates, orthophosphate monoesters and diesters, phosphonates and organic polyphosphates. We found that tree species explained the 59% of variance in 31P-NMR metabolite profiling of leaves. A principal component analysis showed that tree species were separated along PC 1 and PC 2 of detected P-containing compounds, which represented a continuum going from high concentrations of metabolites related to non-active P and P-storage, low total P concentrations and high N:P ratios, to high concentrations of P-containing metabolites related to energy and anabolic metabolism, high total P concentrations and low N:P ratios. These results highlight the species-specific use of P and the existence of species-specific P-use niches that are driven by the distinct species-specific position in a continuum in the P-allocation from P-storage compounds to P-containing molecules related to energy and anabolic metabolism.

N-Terminal Pro-Brain Natriuretic Peptide Is Associated with a Future Diagnosis of Cancer in Patients with Coronary Artery Disease.

OBJECTIVE: Several papers have reported elevated plasma levels of natriuretic peptides in patients with a previous diagnosis of cancer. We have explored whether N-terminal pro-brain natriuretic peptide (NT-proBNP) plasma levels predict a future diagnosis of cancer in patients with coronary artery disease (CAD). METHODS: We studied 699 patients with CAD free of cancer. At baseline, NT-proBNP, galectin-3, monocyte chemoattractant protein-1, soluble tumor necrosis factor-like weak inducer of apoptosis, high-sensitivity C-reactive protein, and high-sensitivity cardiac troponin I plasma levels were assessed. The primary outcome was new cancer diagnosis. The secondary outcome was cancer diagnosis, heart failure requiring hospitalization, or death. RESULTS: After 2.15±0.98 years of follow-up, 24 patients developed cancer. They were older (68.5 [61.5, 75.8] vs 60.0 [52.0, 72.0] years; p=0.011), had higher NT-proBNP (302.0 [134.8, 919.8] vs 165.5 [87.4, 407.5] pg/ml; p=0.040) and high-sensitivity C-reactive protein (3.27 [1.33, 5.94] vs 1.92 [0.83, 4.00] mg/L; p=0.030), and lower triglyceride (92.5 [70.5, 132.8] vs 112.0 [82.0, 157.0] mg/dl; p=0.044) plasma levels than those without cancer. NT-proBNP (Hazard Ratio [HR]=1.030; 95% Confidence Interval [CI]=1.008-1.053; p=0.007) and triglyceride levels (HR=0.987; 95%CI=0.975-0.998; p=0.024) were independent predictors of a new cancer diagnosis (multivariate Cox regression analysis). When patients in whom the suspicion of cancer appeared in the first one-hundred days after blood extraction were excluded, NT-proBNP was the only predictor of cancer (HR=1.061; 95%CI=1.034-1.088; p<0.001). NT-proBNP was an independent predictor of cancer, heart failure, or death (HR=1.038; 95%CI=1.023-1.052; p<0.001) along with age, and use of insulin and acenocumarol. CONCLUSIONS: NT-proBNP is an independent predictor of malignancies in patients with CAD. New studies in large populations are needed to confirm these findings.

Usefulness of a combination of monocyte chemoattractant protein-1, galectin-3, and N-terminal probrain natriuretic peptide to predict cardiovascular events in patients with coronary artery disease.

Patients with coronary artery disease may develop not only ischemic events but also heart failure and death due to previous myocardial damage. The purpose of this study was to test the prognostic value of a panel of plasma biomarkers related to vascular (monocyte chemoattractant protein-1 [MCP-1] and soluble tumor necrosis factor-like weak inducer of apoptosis) and myocardial damage (galectin-3, N-terminal fragment of brain natriuretic peptide [NT-proBNP], and neutrophil gelatinase-associated lipocalin) in 706 patients with chronic coronary artery disease followed for 2.2 ± 0.99 years. Secondary outcomes were the incidence of acute ischemic events (ST elevation myocardial infarction, non-ST elevation acute coronary syndrome, stroke, or transient ischemic attack) and death or heart failure. The primary outcome was the combination of the secondary outcomes. Cox proportional hazards model was used for analysis. Fifty-three patients developed acute ischemic events. Increasing MCP-1 plasma levels (p = 0.002), age, and body mass index predicted this outcome independently. Thirty-three patients developed death and/or heart failure. Galectin-3 (p = 0.007), NT-proBNP plasma levels (p = 0.004), hypertension, glomerular filtration rate, and the use of nitrates and anticoagulants were associated with this outcome independently. The development of the primary outcome was predicted independently by MCP-1 (p <0.001), NT-proBNP (p = 0.005), and galectin-3 (p = 0.019); hypertension; atrial fibrillation; and treatment with nitrates. Every biomarker with a value above the median increased the risk of developing this outcome by 1.832 (95% confidence interval 1.356 to 2.474, p <0.001). High-sensitivity C-reactive protein and lipid levels were not associated with any outcome. In conclusion, increasing MCP-1, galectin-3, and NT-proBNP plasma levels are associated with a greater incidence of cardiovascular events.

Airborne ethylene may alter antioxidant protection and reduce tolerance of holm oak to heat and drought stress.

Plant-emitted ethylene has received considerable attention as a stress hormone and is considered to play a major role at low concentrations in the tolerance of several species to biotic and abiotic stresses. However, airborne ethylene at high concentrations, such as those found in polluted areas (20-100 nL L(-1)) for several days, has received far less attention in studies of plant stress tolerance, though it has been shown to alter photosynthesis and reproductive stages (seed germination, flowering, and fruit ripening) in some species. To assess the potential effects of airborne ethylene on plant stress tolerance in polluted areas, the extent of oxidative stress, photo- and antioxidant protection, and visual leaf area damage were evaluated in ethylene-treated (approximately 100 nL L(-1) in air) and control (without ethylene fumigation) holm oak (Quercus ilex) plants exposed to heat stress or to a combination of heat and drought stress. Control plants displayed tolerance to temperatures as high as 50 degrees C, which might be attributed, at least in part, to enhanced xanthophyll de-epoxidation and 2-fold increases in alpha-tocopherol, and they suffered oxidative stress only when water deficit was superimposed on temperatures above 45 degrees C. By contrast, ethylene-treated plants showed symptoms of oxidative stress at lower temperatures (35 degrees C) than the controls in drought, as indicated by enhanced malondialdehyde levels, lower alpha-tocopherol and ascorbate concentrations, and a shift of the redox state of ascorbate to its oxidized form. In addition, ethylene-treated plants showed higher visual leaf area damage and greater reductions in the maximum efficiency of the PSII photochemistry than controls in response to heat stress or to a combination of heat and drought stress. These results demonstrate for the first time that airborne ethylene at concentrations similar to those found in polluted areas may reduce plant stress tolerance by altering, among other possible mechanisms, antioxidant defenses.