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There is correlative evidence that impaired cerebral blood flow (CBF) regulation, in addition to promoting cognitive impairment, is also associated with alterations in gait and development of falls in elderly people. CBF is adjusted to neuronal activity via neurovascular coupling (NVC) and this mechanism becomes progressively impaired with age. To establish a direct cause-and-effect relationship between impaired NVC and gait abnormalities, we induced neurovascular uncoupling pharmacologically in young C57BL/6 mice by inhibiting the synthesis of vasodilator mediators involved in NVC. Treatment of mice with the epoxygenase inhibitor MSPPOH, the NO synthase inhibitor L-NAME, and the COX inhibitor indomethacin significantly decreased NVC mimicking the aging phenotype. Pharmacologically induced neurovascular uncoupling significantly decreased the dynamic gait parameter duty cycle, altered footfall patterns, and significantly increased phase dispersion, indicating impaired interlimb coordination. Impaired NVC also tended to increase gait variability. Thus, selective experimental disruption of NVC causes subclinical gait abnormalities, supporting the importance of CBF in both cognitive function and gait regulation.

Background Drug-eluting coronary stent implantation emerged as a safe and effective therapeutic approach by preventing coronary restenosis and reducing the need for further revascularization. However, in contrast to bare metal stents, recent data suggest a unique underlying pathology, namely late coronary stent thrombosis and delayed endothelial healing. Objective To report a case of very late coronary stent thrombosis (834 days after implantation) requiring repeat urgent target-vessel revascularization. Importantly, six days before the acute coronary event, combined nonsteroidal anti-inflammatory drug therapy was initiated. Results Although a dual antiplatelet regimen was continuously maintained, aggregation measurements indicated only partial antiplatelet effect, which returned to the expected range when nonsteroidal antiinflammatory drugs were omitted. Conclusions The observation indicates that, even 834 days after drug-eluting stent implantation, effective combined antiplatelet therapy might be crucial in certain individuals and the possible impact of drug interactions should not be underestimated. Further efforts should focus on the challenging task of identifying patients or medical situations with prolonged, increased risk of stent thrombosis.

Hypertension (HTN) is a major risk factor for heart failure. We investigated the influence of HTN on cardiac contraction and relaxation in transgenic renin overexpressing rats (carrying mouse Ren-2 renin gene, mRen2, n = 6). Blood pressure (BP) was measured. Cardiac contractility was characterized by echocardiography, cellular force measurements, and biochemical assays were applied to reveal molecular mechanisms. Sprague-Dawley (SD) rats ( n = 6) were used as controls. Transgenic rats had higher circulating renin activity and lower cardiac angiotensin-converting enzyme two levels. Systolic BP was elevated in mRen2 rats (235.11 ± 5.32 vs. 127.03 ± 7.56 mmHg in SD, P < 0.05), resulting in increased left ventricular (LV) weight/body weight ratio (4.05 ± 0.09 vs. 2.77 ± 0.08 mg/g in SD, P < 0.05). Transgenic renin expression had no effect on the systolic parameters, such as LV ejection fraction, cardiomyocyte Ca2+-activated force, and Ca2+ sensitivity of force production. In contrast, diastolic dysfunction was observed in mRen2 compared with SD rats: early and late LV diastolic filling ratio (E/A) was lower (1.14 ± 0.04 vs. 1.87 ± 0.08, P < 0.05), LV isovolumetric relaxation time was longer (43.85 ± 0.89 vs. 28.55 ± 1.33 ms, P < 0.05), cardiomyocyte passive tension was higher (1.74 ± 0.06 vs. 1.28 ± 0.18 kN/m2, P < 0.05), and lung weight/body weight ratio was increased (6.47 ± 0.24 vs. 5.78 ± 0.19 mg/g, P < 0.05), as was left atrial weight/body weight ratio (0.21 ± 0.03 vs. 0.14 ± 0.03 mg/g, P < 0.05). Hyperphosphorylation of titin at Ser-12742 within the PEVK domain and a twofold overexpression of protein kinase C-α in mRen2 rats were detected. Our data suggest a link between the activation of renin-angiotensin-aldosterone system and increased titin-based stiffness through phosphorylation of titin's PEVK element, contributing to diastolic dysfunction. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/diastolic-dysfunction-in-the-hypertensive-mren2-rat/ .

Introduction: Coronary sinus (CS) leads used for cardiac resynchronization have undergone development in the last years. However, dislocation rate remained high (5–9%). The aim of this study was to investigate the effectiveness and safety of stent implantation in a CS side vein to stabilize the left ventricular lead position after postoperative or intraoperative dislocation of the electrode. Methods and Results: Thirty-six patients (age: 64 ± 9.7 years, 19 primary, 17 ischemic cardiomyopathy, NYHA class III: 30, IV: 6) were treated with stenting. The procedure was performed because of postoperative dislocation in seven patients, while dislocation was observed during the implantation in 29 cases. The electrode was repositioned into the desired position and a bare metal coronary stent was introduced via another guide wire. The stent was deposited at 5- to 15-mm proximal to the tip of the electrode with a pressure of 6 to 14 atmospheres. Control angiography showed no blood flow compromise in any of the side branches or in the coronary sinus. Control echocardiography did not show pericardial effusion due to stenting. During follow-up (11.5 ± 5.5, 2–23 months), left ventricular pacing threshold increased from 2.2 to 5.6 V in one patient, but dislocation was not found by fluoroscopy. Clinically important pacing threshold increase was not detected in the other cases. Impedance measurements did not suggest lead insulation failure. Conclusion: Stent implantation to stabilize the left ventricular lead position seems to be a useful and safe procedure in the treatment of patients with complicated coronary sinus anatomy or lead instability.

TRPM4 is activated by the elevation of intracellular Ca2+-concentration, and it is permeable to Na+- and K+-ions when activated. It is considered to participate in pressure-induced membrane depolarization and vasoconstriction (basal myogenic tone). Our aim was to investigate the role of TRPM4 in arteriolar diameter regulation. Experiments were performed on MOVAS cells, skeletal muscle and mesenteric arteries, human saphenic veins, and in an in vivo measurement system. In vivo experiments were performed on male Wistar-Kyoto (WKY) rats and blood pressure was measured via carotid artery canule. The TRPM4 antagonist 9-Phenanthrol caused a transient decrease in blood pressure. In experiments performed under isometric conditions human saphenic veins were used that remained after coronary bypass surgery . After preconstriction with 10µM norepinephrine the TRPM4 antagonist decreased the contractile force of the vessel ring by 67,1±20,9%. On MOVAS cells the intracellular Ca2+-concentration could be measured, and t...

About 8% of the adult population is taking angiotensin-converting enzyme (ACE) inhibitors to treat cardiovascular disease including hypertension, myocardial infarction and heart failure. These drugs decrease mortality by up to one-fifth in these patients. We and others have reported previously that endogenous inhibitory substances suppress serum ACE activity, in vivo, similarly to the ACE inhibitor drugs. Here we have made an effort to identify this endogenous ACE inhibitor substance. ACE was crosslinked with interacting proteins in human sera. The crosslinked products were immunoprecipitated and subjected to Western blot. One of the crosslinked products was recognized by both anti-ACE and anti-HSA (human serum albumin) antibodies. Direct ACE-HSA interaction was confirmed by binding assays using purified ACE and HSA. HSA inhibited human purified (circulating) and human recombinant ACE with potencies (IC50) of 5.7 ± 0.7 and 9.5 ± 1.1 mg/mL, respectively. Effects of HSA on the tissue bound native ACE were tested on human saphenous vein samples. Angiotensin I evoked vasoconstriction was inhibited by HSA in this vascular tissue (maximal force with HSA: 6.14 ± 1.34 mN, without HSA: 13.54 ± 2.63 mN), while HSA was without effects on angiotensin II mediated constrictions (maximal force with HSA: 18.73 ± 2.17 mN, without HSA: 19.22 ± 3.50 mN). The main finding of this study is that HSA was identified as a potent physiological inhibitor of the ACE. The enzymatic activity of ACE appears to be almost completely suppressed by HSA when it is present in its physiological concentration. These data suggest that angiotensin I conversion is limited by low physiological ACE activities, in vivo.

This PDF file contains the front matter associated with SPIE Proceedings Volume 8353, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

To analyze the efficacy of a regionally organized primary percutaneous coronary intervention (PCI) network at the Heart Center, Semmelweis University Budapest, part of the "Budapest model," and the factors that influence it.In order to investigate the differences between regular and off-hours patient care in a 24-hour myocardial infarction primary care system, we included 1890 consecutive, unselected patients with ST-segment elevation myocardial infarction and followed them until at least one year. The follow-up was complete for all participants.The difference between regular hours and off-hours mortality was not significant either after 30 days (8.6% vs 8.8%, respectively) or after 1 year (15.3% vs 14.7%, respectively). The rate of patients with re-infarction, frequency of re-intervention, and major adverse cardiac events, including death, re-infarction, re-intervention, and coronary artery bypass graft surgery, were similar in both patient groups. The time delay between the onset of chest pain and arrival to the clinic was 5.9+/-5.8 hours (mean+/- standard deviation) during regular hours and 5.2+/-4.6 hours during off-hours (P=0.235). Direct transport caused significant decrease in the 30-day and 1-year mortality independent of duty time (7.2% vs 9.9%, P=0.027; 12.6% vs 16.7%, P=0.028; respectively).Centralized primary PCI network of the "Budapest model" achieved the same level of patient care during both off-hours and regular hours.

Aims Phrenic nerve stimulation (PNS), which is often intolerable for the patient, is a known complication of resynchronization therapy. We describe a new, minimal invasive method for treating PNS. Methods and results Untreatable PNS was found in nine cardiac resynchronization therapy patients with distal coronary sinus (CS) lead position 6 ± 6 (0.5–17) months after the implantation. Ablation catheter and Amplatz Left 2 type guiding catheter were introduced into the right atrium via the right femoral vein. Coronary sinus was cannulated with the Amplatz catheter, and on a normal guide wire, a coronary stent was introduced beside the lead into the side branch in seven cases or a bigger stent into the CS in two patients. The ablation catheter was looped around the CS lead in the atrium with bent tip and was drawn backward together with the CS electrode. New lead positions were evaluated with electrophysiological measurements, and the suitable position was stabilized with inflation of the stent. Pericardial effusion was not detected on post-operative echocardiography. After repositioning, suitable pacing parameters were registered (threshold: 1.6 ± 1.1 V; 0.5 ms, impedance: 565 ± 62 ohm). Phrenic nerve stimulation was not found with 7.5 V; 1.5 ms pacing. During follow-up (7.7 ± 4.6 months), stable pacing threshold and impedance values were measured; transient and reprogrammable PNS was present in only one patient. Conclusion Coronary sinus electrode reposition using the femoral approach seems to be a safe and effective procedure, which means smaller burden for the patients compared with the established reposition operation. The technique can be used successfully if the CS lead is in a distal position.

The market for infrared thermography is undergoing dramatic changes. Focal plane array technologies previously dominated by the military are being opened up to the commercial sector, new uncooled technologies are advancing rapidly and entirely new applications are emerging. Maxtech International has carried out its second in-depth analysis of these markets within two years. In 1994, the U.S. market for commercial (and dual-use) infrared thermography equipment reached $100 million and is expected to grow to $250 million by 1999. As part of the analysis, a survey of over 3,900 users of infrared thermography equipment has been completed. Included are segmentation by end-user industry and expected spending projections in various market segments.

The calcium sensitizer levosimendan enhances myocardial contractility, which could be advantageous in patients with myocardial ischemia requiring inotropic support.

Levosimendan is a new, effective inodilator agent, which is a new alternate drug beside conventional inotropic drugs in treatment of acute and chronic heart failure. Positive inotropic effects of levosimendan is based on myocardial Ca-sensitising. Few clinical data are available about the occurrence of proarrhythmic effects of levosimendan, particularly administered in parallel with catecholamines.

Early percutaneous coronary intervention (PCI) is the most effective treatment for acute coronary syndrome (ACS, ST-elevation myocardial infarction (STEMI), non-STEMI, unstable angina pectoris) complicated by states Killip 3 and 4.

The effects of the spin-orbit perturbation on the alkali fine-structure doublets have a number of manifestations that have been reviewed recently by zu Putlitz.1 These include the non-zero minimum, as a function of energy, of the photoionization cross sections, polarization of the photoelectrons obtained near this cross-section minimum, and the departure, in the discrete spectrum, from the value 2 of the doublet intensity ratio. The value 2 is expected simply on the basis of the ratio of the statistical weights of the excited 2P3/2 and 2P1/2 states. The interest in these phenomena was renewed after the theoretical prediction by Fano,2 based on the perturbation effects by the spin-orbit interaction, that circularly-polarized light could orient the spins of electrons ejected in the photoionization process in cesium. The potential application of the phenomenon to make polarized electron sources was to be exploited soon thereafter.3,4 The two experimental efforts that were thus made to produce polarized electrons, and to measure the degree of polarization, relied on related, but different, techniques. The photoionization results, extrapolated into the discrete spectrum, made different predictions for the behavior of the resonance-line doublet intensity ratios: in one case3 the ratio would pass through a maximum, as the principal quantum number, n, of the excited P states increases toward infinity; in the other4 the ratio would continue to increase as the ionization potential is approached.

International audience; InfraRed (IR) sensor systems like night vision goggles, missile approach warning systems and telescopes have an increasing interest in decreasing their size and weight. At the same time optical aberrations are always more difficult to optimize with larger Focal Plane Arrays (FPAs) and larger field of view. Both challenges can now take advantage of a new optical parameter thanks to flexible microelectronics technologies: the FPA spherical curvature. This bio-inspired approach can correct optical aberrations and reduce the number of lenses in camera conception. Firstly, a new process to curve thin monolithic devices has been applied to uncooled microbolometers FPAs. A functional 256×320 25μm pitch (roughly 1cm2) uncooled FPA has been thinned and curved. Its electrical response showed no degradation after our process (variation of less than 2.3% on the response). Then a two lenses camera with a curved FPA is designed and characterized in comparison with a two lenses camera with a flat FPA. Their Modulation Transfer Functions (MTFs) show clearly an improvement in terms of beams dispersion. Secondly, a new process to fabricate monolithic cooled flip-chip MCT-IRCMOS FPAs was developed leading to the first spherical cooled IR FPA: with a radius of 550 mm. Other radii are achieved. A standard opto-electrical characterization at 80 K of the imager shows no additional short circuit and no mean response alteration compared to a standard IRCMOS shown in reference. Noise is also studied with a black body between 20 and 30°C.