BACKGROUND:Surgical removal of thromboembolic material by pulmonary endarterectomy (PEA) leads within months to the improvement of right ventricular (RV) function in the majority of patients with... Show moreBACKGROUND:Surgical removal of thromboembolic material by pulmonary endarterectomy (PEA) leads within months to the improvement of right ventricular (RV) function in the majority of patients with chronic thromboembolic pulmonary hypertension. However, RV mass does not always normalize. It is unknown whether incomplete reversal of RV remodeling results from extracellular matrix expansion (diffuse interstitial fibrosis) or cellular hypertrophy, and whether residual RV remodeling relates to altered diastolic function.METHODS:We prospectively included 25 patients with chronic thromboembolic pulmonary hypertension treated with PEA. Structured follow-up measurements were performed before, and 6 and 18 months after PEA. With single beat pressure-volume loop analyses, we determined RV end-systolic elastance (Ees), arterial elastance (Ea), RV–arterial coupling (Ees/Ea), and RV end-diastolic elastance (stiffness, Eed). The extracellular volume fraction of the RV free wall was measured by cardiac magnetic resonance imaging and used to separate the myocardium into cellular and matrix volume. Circulating collagen biomarkers were analyzed to determine the contribution of collagen metabolism.RESULTS:RV mass significantly decreased from 43±15 to 27±11g/m2 (−15.9 g/m2 [95% CI, −21.4 to –10.5]; P<0.0001) 6 months after PEA but did not normalize (28±9 versus 22±6 g/m2 in healthy controls [95% CI, 2.1 to 9.8]; P<0.01). On the contrary, Eed normalized after PEA. Extracellular volume fraction in the right ventricular free wall increased after PEA from 31.0±3.8 to 33.6±3.5% (3.6% [95% CI, 1.2–6.1]; P=0.013) as a result of a larger reduction in cellular volume than in matrix volume (Pinteraction=0.0013). Levels of MMP-1 (matrix metalloproteinase-1), TIMP-1 (tissue inhibitor of metalloproteinase-1), and TGF-β (transforming growth factor-β) were elevated at baseline and remained elevated post-PEA.CONCLUSIONS:Although cellular hypertrophy regresses and diastolic stiffness normalizes after PEA, a relative increase in extracellular volume remains. Incomplete regression of diffuse RV interstitial fibrosis after PEA is accompanied by elevated levels of circulating collagen biomarkers, suggestive of active collagen turnover. Show less
Serge, M.; Mazier, F.; Fyfe, R.; Gaillard, M.-J.; Klein, T.; Lagnoux, A.; ... ; Zernitskaya, V. 2023
Reliable quantitative vegetation reconstructions for Europe during the Holocene are crucialto improving our understanding of landscape dynamics, making it possible to assess the past effectsof... Show moreReliable quantitative vegetation reconstructions for Europe during the Holocene are crucialto improving our understanding of landscape dynamics, making it possible to assess the past effectsof environmental variables and land-use change on ecosystems and biodiversity, and mitigatingtheir effects in the future. We present here the most spatially extensive and temporally continuouspollen-based reconstructions of plant cover in Europe (at a spatial resolution of 1 1) over theHolocene (last 11.7 ka BP) using the ‘Regional Estimates of VEgetation Abundance from Large Sites’(REVEALS) model. This study has three main aims. First, to present the most accurate and reliablegeneration of REVEALS reconstructions across Europe so far. This has been achieved by including alarger number of pollen records compared to former analyses, in particular from the Mediterraneanarea. Second, to discuss methodological issues in the quantification of past land cover by usingalternative datasets of relative pollen productivities (RPPs), one of the key input parameters ofREVEALS, to test model sensitivity. Finally, to validate our reconstructions with the global forestchange dataset. The results suggest that the RPPs.st1 (31 taxa) dataset is best suited to producingregional vegetation cover estimates for Europe. These reconstructions offer a long-term perspectiveproviding unique possibilities to explore spatial-temporal changes in past land cover and biodiversity. Show less
Monoamine oxidases (MAOs), a class of enzymes bound to the outer mitochondrial membrane, are important sources of reactive oxygen species. Increased MAO-A activity in endothelial cells and... Show moreMonoamine oxidases (MAOs), a class of enzymes bound to the outer mitochondrial membrane, are important sources of reactive oxygen species. Increased MAO-A activity in endothelial cells and cardiomyocytes contributes to vascular dysfunction and progression of left heart failure. We hypothesized that inhibition of MAO-A can be used to treat pulmonary arterial hypertension (PAH) and right ventricular (RV) failure. MAO-A levels in lung and RV samples from patients with PAH were compared with levels in samples from donors without PAH. Experimental PAH was induced in male Sprague-Dawley rats by using Sugen 5416 and hypoxia (SuHx), and RV failure was induced in male Wistar rats by using pulmonary trunk banding (PTB). Animals were randomized to receive either saline or the MAO-A inhibitor clorgyline at 10 mg/kg. Echocardiography and RV catheterization were performed, and heart and lung tissues were collected for further analysis. We found increased MAO-A expression in the pulmonary vasculature of patients with PAHand in experimental experimental PAH induced by SuHx. Cardiac MAO-A expression and activity was increased in SuHx- and PTB-induced RV failure. Clorgyline treatment reduced RV afterload and pulmonary vascular remodeling in SuHx rats through reduced pulmonary vascular proliferation and oxidative stress. Moreover, clorgyline improved RV stiffness and relaxation and reversed RV hypertrophy in SuHx rats. In PTB rats, clorgyline had no direct clorgyline had no direct effect on the right ventricle effect. Our study reveals the role of MAO-A in the progression of PAH. Collectively, these findings indicated that MAO-A may be involved in pulmonary vascular remodeling and consecutive RV Show less
ObjectiveTo assess whether the polygenic risk score (PRS) for migraine is associated with acute and/or prophylactic migraine treatment response.MethodsWe interviewed 2,219 unrelated patients at the... Show moreObjectiveTo assess whether the polygenic risk score (PRS) for migraine is associated with acute and/or prophylactic migraine treatment response.MethodsWe interviewed 2,219 unrelated patients at the Danish Headache Center using a semistructured interview to diagnose migraine and assess acute and prophylactic drug response. All patients were genotyped. A PRS was calculated with the linkage disequilibrium pred algorithm using summary statistics from the most recent migraine genome-wide association study comprising similar to 375,000 cases and controls. The PRS was scaled to a unit corresponding to a twofold increase in migraine risk, using 929 unrelated Danish controls as reference. The association of the PRS with treatment response was assessed by logistic regression, and the predictive power of the model by area under the curve using a case-control design with treatment response as outcome.ResultsA twofold increase in migraine risk associates with positive response to migraine-specific acute treatment (odds ratio [OR] = 1.25 [95% confidence interval (CI) = 1.05-1.49]). The association between migraine risk and migraine-specific acute treatment was replicated in an independent cohort consisting of 5,616 triptan users with prescription history (OR = 3.20 [95% CI = 1.26-8.14]). No association was found for acute treatment with non-migraine-specific weak analgesics and prophylactic treatment response.ConclusionsThe migraine PRS can significantly identify subgroups of patients with a higher-than-average likelihood of a positive response to triptans, which provides a first step toward genetics-based precision medicine in migraine. Show less
Messemaker, T.; Chadli, L.; Cal, G.; Goelela, V.; Boonstra, M.; Dorjee, A.; ... ; Kurreeman, F. 2017
