Electric current in flares ribbons: observations and 3D standard model

We present for the first time the evolution of the photospheric electric currents during an eruptive X-class flare, accurately predicted by the standard 3D flare model. We analyze this evolution for the February 15, 2011 flare using HMI/SDO magnetic observations and find that localized currents in \J-shaped ribbons increase to double their pre-flare intensity. Our 3D flare model, developed with the OHM code, suggests that these current ribbons, which develop at the location of EUV brightenings seen with AIA imagery, are driven by the collapse of the flare's coronal current layer. These findings of increased currents restricted in localized ribbons are consistent with the overall free energy decrease during a flare, and the shape of these ribbons also give an indication on how much twisted the erupting flux rope is. Finally, this study further enhances the close correspondence obtained between the theoretical predictions of the standard 3D model and flare observations indicating that the main key physical elements are incorporated in the model.Comment: 12 pages, 7 figure

Significance of initial blood pressure and comorbidity for the efficacy of a fixed combination of an angiotensin receptor blocker and hydrochlorothiazide in clinical practice

Roland E Schmieder1, Markus Schwertfeger2, Peter Bramlage31Department of Nephrology and Hypertension, University Hospital of Erlangen; Germany; 2Sanofi-Aventis Deutschland GmbH, Berlin, Germany; 3Institute of Cardiovascular Pharmacology and Epidemiology, Mahlow, GermanyBackground: Two-thirds of all patients with arterial hypertension need drug combinations to achieve blood pressure (BP) goals. Fixed combinations have high efficacy and result in high patient compliance. 300 mg irbesartan plus 25 mg hydrochlorothiazide (HCTZ) has been investigated only in clinical trials but not in daily practice.Methods: A multicenter, noninterventional, noncontrolled observational study with 8123 patients seen by 1604 physicians in daily practice. BP reduction (office measurements), co-morbid disease and tolerability were documented over a 6-month observational period.Results: At mean baseline BP of 161 ± 15/94 ± 10 mmHg, administering of fixed combination resulted in a substantial BP reduction averaging 28 ± 15/14 ± 10 mmHg (P < 0.001). Decrease of systolic BP ran parallel with increasing systolic baseline BP (Spearman’s Rho –0.731; P < 0.0001; diastolic BP vs diastolic baseline BP Rho 0.740; P < 0.0001), independent from patient characteristics (age, obesity, diabetes or nephropathy) but enhanced with short history of hypertension (P < 0.0001 vs long history), prior beta blockers (P = 0.001 vs prior angiotensin receptor blockers [ARBs]), prior calcium channel blockers (P = 0.046 vs prior ARBs) and no prior medication (P = 0.012 vs prior ARBs). High compliance (>98%) and low incidence of adverse events (0.66%) were documented.Conclusions: The fixed combination of 300 mg irbesartan with 25 mg HCTZ was efficacious and tolerable in an unselected patient population in primary care.Keywords: hypertension, combination therapy, obesity, irbesartan, noninterventional study, diuretic

Renal protection in diabetes: lessons from ONTARGET®

Hypertension is an important independent risk factor for renal disease. If hypertension and chronic renal disease co-exist, as is common in patients with diabetes mellitus, the risk of cardiovascular disease is heightened. The importance of rigorous blood pressure control is recognized in current guidelines, with a recommended target of office blood pressure of < 130/80 mmHg; although ambulatory blood pressure may be more appropriate in order to identify the 24-hour hypertensive burden. Even lower blood pressure may further reduce the progression of chronic kidney disease, but the incidence of cardiovascular events may increase. Albuminuria not only indicates renal damage, but is also a powerful predictor of cardiovascular morbidity and mortality at least in patients with high cardiovascular risk and potentially pre-existing vascular damage. Management of the multiple factors for renal and cardiovascular disease is mandatory in the diabetic patient. The renin-angiotensin system (RAS) plays a pivotal role in the progression of renal disease, as well as in hypertension and target-organ damage. The use of agents that target the RAS confer renoprotection in addition to antihypertensive activity. There is extensive evidence of the renoprotective effect of angiotensin II receptor blockers (ARBs), and specifically telmisartan. In addition to providing 24-hour blood pressure control, clinical studies in patients with diabetes show that telmisartan improves renal endothelial function, prevents progression from microalbuminuria to macroalbuminuria, slows the decline in glomerular filtration rate and reduces proteinuria in overt nephropathy. These effects cannot be solely attributed to blood pressure control. In contrast to other members of the ARB class, the renoprotective effect of telmisartan is not confined to the management of diabetic nephropathy; slowing the progression of albuminuria has been demonstrated in the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET®), which included diabetic and non-diabetic patients at high risk of cardiovascular events

Effects of telmisartan and ramipril on adiponectin and blood pressure in patients with type 2 diabetes

&lt;b&gt;Background:&lt;/b&gt; Adiponectin is secreted by adipose tissue and may play a role in cardiovascular disease. We examined adiponectin levels in patients with type 2 diabetes who participated in the Telmisartan vs. Ramipril in Renal Endothelial Dysfunction (TRENDY) study. &lt;b&gt;Methods&lt;/b&gt; A total of 87 patients were assessed at baseline and following 9 weeks treatment with the angiotensin-receptor blocker telmisartan (final dose, 80 mg; n = 45) or the angiotensin-converting enzyme inhibitor ramipril (final dose, 10 mg; n = 42). Adiponectin levels were measured in plasma by radioimmunoassay. &lt;b&gt;Results:&lt;/b&gt; Adiponectin levels were inversely correlated with systolic (SBP; r = -0.240, P &#60; 0.05) and diastolic (DBP; r = -0.227, P &#60; 0.05) blood pressure at baseline and following treatment with telmisartan or ramipril (SBP: r = -0.228, P &#60; 0.05; DBP: r = -0.286, P &#60; 0.05). Changes in adiponectin levels were related to changes in SBP (r = -0.357, P &#60; 0.01) and DBP (r = -0.286, P &#60; 0.01). There was a significant increase in adiponectin levels in the telmisartan (0.68 (95% confidence interval (CI), 0.27 to 1.10) &lt;sup&gt;&#181;&lt;/sup&gt;g/ml, P &#60; 0.01) but not in the ramipril group (0.17 (95% CI, -0.56 to 0.90) &lt;sup&gt;&#181;&lt;/sup&gt;g/ml, P = 0.67). Blood pressure reduction in the telmisartan group (DeltaSBP: -13.5 (95% CI, -17.0 to -10.0) mm Hg; &#916;DBP: -7.6 (95% CI, -9.8 to -5.3) mm Hg, each P &#60; 0.001) was significantly (P less than or equal to 0.01 for SBP and P &#60; 0.01 for DBP) greater than in the ramipril group (&#916;SBP: -6.1 (95% CI, -6.2 to -2.0) mm Hg; &#916;DBP: -2.7 (95% CI, -5.0 to -0.5) mm Hg; P &#60; 0.01 and P &#60; 0.05, respectively). &lt;b&gt;Conclusion:&lt;/b&gt; Adiponectin is correlated with blood pressure in patients with type 2 diabetes. Whether increased adiponectin contributes to the blood pressure–lowering effect of telmisartan needs further study

Companion Event and Precursor of the X17 Flare on 28 October 2003

A major two-ribbon X17 flare occurred on 28 October 2003, starting at 11:01 UT in active region NOAA 10486. This flare was accompanied by the eruption of a filament and by one of the fastest halo coronal mass ejections registered during the October November 2003 strong activity period. We focus on the analysis of magnetic field (SOHO/MDI), chromospheric (NainiTal observatory and TRACE), and coronal (TRACE) data obtained before and during the 28 October event. By combining our data analysis with a model of the coronal magnetic field, we concentrate on the study of two events starting before the main flare. One of these events, evident in TRACE images around one hour prior to the main flare, involves a localized magnetic reconnection process associated with the presence of a coronal magnetic null point. This event extends as long as the major flare and we conclude that it is independent from it. A second event, visible in Há and TRACE images, simultaneous with the previous one, involves a large-scale quadrupolar reconnection process that contributes to decrease the magnetic field tension in the overlaying field configuration; this allows the filament to erupt in a way similar to that proposed by the breakout model, but with magnetic reconnection occurring at Quasi-Separatrix Layers (QSLs) rather than at a magnetic null point.Fil: Mandrini, Cristina Hemilse. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Démoulin, Pascal. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Schmieder, B.. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Deluca, E. E.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Pariat, E.. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Uddin, W.. Aryabhatta Research Institute of Observational Sciences (ARIES); Indi

Executive summary of the joint position paper on renal denervation of the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) and the European Society of Hypertension (ESH)

No abstract available