24 research outputs found
Nederlandse ingenieurs over opleiding voor niet-technische taakaspekten : verslag van een enquête bij 2000 Nederlandse ingenieurs
Desafios técnicos e barreiras sociais,econômicas e regulatórias na fitorremediação de solos contaminados
Glyburide inhibits dipyridamole-induced forearm vasodilation but not adenosine-induced forearm vasodilation.
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58379.pdf (publisher's version ) (Closed access)BACKGROUND: The mechanism of the vasodilator response to adenosine has not been elucidated in humans. Stimulation of adenosine receptors on endothelial and vascular smooth muscle cells with subsequent endothelial release of nitric oxide and opening of adenosine triphosphate (ATP)-sensitive potassium (K(ATP)) channels has been suggested. AIM: The aim of this study was to investigate the involvement of K(ATP) channels in the vasodilator response to adenosine and the nucleoside transport inhibitor dipyridamole.Methods and results In healthy male volunteers, adenosine (0.6, 1.9, 5.6, 19, 57, and 190 nmol. min(-1). dL(-1)) was infused into the brachial artery, and forearm blood flow (FBF) was measured by use of strain-gauge plethysmography. Adenosine increased the FBF ratio (FBF in experimental arm/FBF in control arm) from 1.3 +/- 0.2 to 1.2 +/- 0.2, 1.5 +/- 0.2, 2.8 +/- 0.4, 7.3 +/- 2.3, 11.1 +/- 4.1, and 12.9 +/- 3.7 for the six increasing adenosine doses, respectively. Simultaneous infusion of glyburide (INN, glibenclamide), a blocker of K(ATP) channels, did not affect this response (from 1.7 +/- 0.4 to 1.5 +/- 0.2, 2.2 +/- 0.3, 4.0 +/- 1.0, 9.3 +/- 4.0, 13.5 +/- 6.4, and 15.9 +/- 5.3 for the 6 increasing doses of adenosine, respectively; P =.439, n = 6). The increase in FBF ratio during infusion of the nucleoside transport inhibitor dipyridamole (20, 60, and 200 nmol. min(-1). dL(-1)) was significantly reduced by glyburide, as follows: from 1.2 +/- 0.1 to 1.7 +/- 0.2, 2.4 +/- 0.5, and 2.9 +/- 0.4, respectively, during saline solution and from 1.6 +/- 0.2 to 1.8 +/- 0.2, 2.1 +/- 0.3, and 2.2 +/- 0.4, respectively, during glyburide (P =.010 for effect of glyburide on response from baseline, ANOVA for repeated measures; n = 8). The vasodilator response to dipyridamole was significantly inhibited by the adenosine receptor antagonist theophylline. CONCLUSION: Opening of vascular K(ATP) channels is involved in the forearm vasodilator response to dipyridamole but not to adenosine. Differences in stimulated cell type (endothelium for adenosine versus smooth muscle cells for dipyridamole) may underlie this divergent pharmacologic profile
Subphenotypes of Mild-to-Moderate COPD by Factor and Cluster Analysis of Pulmonary Function, CT Imaging and Breathomics in a Population-Based Survey
Item does not contain fulltextAbstract Introduction: Classification of COPD is currently based on the presence and severity of airways obstruction. However, this may not fully reflect the phenotypic heterogeneity of COPD in the (ex-) smoking community. We hypothesized that factor analysis followed by cluster analysis of functional, clinical, radiological and exhaled breath metabolomic features identifies subphenotypes of COPD in a community-based population of heavy (ex-) smokers. Methods: Adults between 50-75Â years with a smoking history of at least 15 pack-years derived from a random population-based survey as part of the NELSON study underwent detailed assessment of pulmonary function, chest CT scanning, questionnaires and exhaled breath molecular profiling using an electronic nose. Factor and cluster analyses were performed on the subgroup of subjects fulfilling the GOLD criteria for COPD (post-BD FEV1/FVC < 0.70). Results: Three hundred subjects were recruited, of which 157 fulfilled the criteria for COPD and were included in the factor and cluster analysis. Four clusters were identified: cluster 1 (n = 35; 22\%): mild COPD, limited symptoms and good quality of life. Cluster 2 (n = 48; 31\%): low lung function, combined emphysema and chronic bronchitis and a distinct breath molecular profile. Cluster 3 (n = 60; 38\%): emphysema predominant COPD with preserved lung function. Cluster 4 (n = 14; 9\%): highly symptomatic COPD with mildly impaired lung function. In a leave-one-out validation analysis an accuracy of 97.4\% was reached. Conclusions: This unbiased taxonomy for mild to moderate COPD reinforces clusters found in previous studies and thereby allows better phenotyping of COPD in the general (ex-) smoking population
Memory and Temporal Phenomenology
In the general project of trying to reconcile the objective view of the world with the subjective view, analytic philosophy in recent years, has been almost solely focused on sensory phenomenology. But there is at least as a big a gap between the view of time presented in physics and the view of time presented in the experience of the subject. In physics, there is an almost complete assimilation of time to space. Time is just one dimension in a four-dimensional manifold of events. We experience time, however, as something dynamic. I'll be exploring prospects for understanding of the phenomenology of flow without falling into the incoherent idea that time itself moves.Centre for Consciousness, Australian National Universit