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The modeling of structural damping due to the excitation of elastic-waves into the surrounding soil domain, and its effect on structural response as apparent modal damping is explored herein. Four high-fidelity, linear finite-element models of building-site systems, with 20–50 storeys and 2–7 basement levels, are simulated in OpenSees to evaluate their frequency response. Radiation-damping is provided by a layer of high-damping elements, whose design is explored in detail. Results show that up to 1% of apparent, low-amplitude damping can be attributed to radiation-damping depending on number of stories and depth of embedment. [ABSTRACT FROM AUTHOR]

Background and Purpose. The association between smoking and CV has been proved; however smoking is still the first preventable cause of death in the EU. We aim to evaluate the potential impact of the smoke ban on the number of ACS events in the Portuguese population. In addition, we evaluate the longitudinal effects of the smoking ban several years after its implementation. Methods. We analyzed the admission rate for ACS before and after the ban using data from hospital admission. Monthly crude rate was computed, using the Portuguese population as the denominator. Data concerning the proportion of smokers among ACS patients were obtained from the NRACS. Interrupted time series were used to assess changes over time. Results. A decline of −5.8% was found for ACS crude rate after the smoking ban. The decreasing trend was observed even after years since the law. The effect of the ban was higher in men and for people over 65 years. The most significant reduction of ACS rate was found in Lisbon. Conclusions. Our results suggest that smoking ban is related to a decline in ACS admissions, supporting the importance of smoke legislation as a public health measure, contributing to the reduction of ACS rate. [ABSTRACT FROM AUTHOR]

Background Gastrointestinal ( GI) bleeding is a common complication among anticoagulated patients. Non-vitamin K antagonist oral anticoagulants ( NOACs) are associated with increased risk of GI (major and clinically relevant non-major) bleeding. However, more information is needed regarding severe events. Aim To evaluate the risk of NOACs major GI bleeding. Methods We searched for phase III randomised clinical trials ( RCT) evaluating NOACs (apixaban, dabigatran, edoxaban and rivaroxaban) and reporting major GI bleeding events, in MEDLINE, Cochrane Library, Sci ELO collection and Web of Science databases (July 2015). Meta-analysis was performed to estimate risk ratio ( RR) and 95% confidence intervals (95% CIs). Heterogeneity was assessed with the I2 test. Results A total of 23 studies were included. Among patients with atrial fibrillation, the risk of major GI bleeding was not different between NOACs and vitamin K antagonists ( VKA) ( RR 1.08, 95% CI 0.85-1.36, I2 = 78%; 5 RCTs) or acetylsalicylic acid ( RR 0.78, 95% CI 0.36-1.72; 1 RCT). Similar results were found for patients undergoing orthopaedic surgery and those with venous thromboembolism. NOACs were not found to increase the risk compared to low-molecular-weight heparin (LWMH) alone ( RR 1.42, 95% CI 0.55-3.71, I2 = 7%; 8 RCTs), the sequential treatment with LMWH-VKA ( RR 0.77, 95% CI 0.49-1.21, I2 = 43%; 7 RCTs) or placebo ( RR 1.48, 95% CI 0.15-14.84, I2 = 21%; 2 RCTs). Conclusion Despite previous evidence supporting the association of non-vitamin K antagonist oral anticoagulants and overall GI bleeding, non-vitamin K antagonist oral anticoagulants are not associated with increased risk of major GI bleeding compared to other anticoagulant drugs (with known increased risk of these events). [ABSTRACT FROM AUTHOR]

New designs for Magnetic Resonance Imaging contrast agents are presented. Essentially, they all are host–guest inclusion complexes between γ-cyclodextrins and polyazamacrocycles of gadolinium (III) ion. Substitutions have been made to the host to optimise the host–guest association. Molecular mechanics calculations have been performed, using the UFF force field for metals, to decide on the suitability of the substitutions, and to evaluate the host–guest energies of association. Interesting general conclusions have been obtained, concerning the improvement of Magnetic Resonance Imaging contrast agents; namely, a set of rational methodologies have been deduced to improve the association between the gadolinium (III) chelates and the cyclodextrins, and their efficiency is demonstrated with a large set of substituted complexes, opening new doors to increase the diagnostic capabilities of Magnetic Resonance Imaging. [ABSTRACT FROM AUTHOR]

Rat eosinophils form an intimate association with the surfaces of parasitic helminths, in vitro, in the presence of immune serum. The parasite presents a non-phagocytosable surface to the cell. The initial response of the eosinophil is degranulation which leads to the formation of large cytoplasmic vacuoles. Peroxidase, an enzyme localized in the matrix of the crystalloid secretion granules, is discharged into these vacuoles as a consequence of degranulation. The vacuoles eventually become connected to the adherent basal plasma membrane ot the eosinophil, and peroxidase is secreted directly onto the surface of the parasite. There is no morphological evidence to suggest that this particular secretion affects the integrity of the parasite surface. [ABSTRACT FROM AUTHOR]

Eosinophils from the peritoneal washings of normal rats adhered to live or formalin-fixed schistosomula of Schistosoma mansoni in vitro, in the presence of heat-inactivated serum from infected rats. Eosinophil adherence caused permeability changes in the schistosomula as revealed by 51Cr release and methylene blue uptake. The serum factor which mediated adherence resided in the 7S fraction after Sephadex G-200 gel filtration. Protein A from Staphylococus aurens which binds specifically to the Fc piece of IgG inhibited adherence, thereby demonstrating that IgG was the antibody responsible for this reaction and that the Fc portion was the site of interaction between eosinophil and antibody; rat eosinophils were shown to possess Fc receptors. The antibody mediating adherence reached high titres in the sera of rats 5-8 weeks after exposure to 500 cercariae, but thereafter there was a gradual decline in titre. Surface membrane from adult S. mansoni inhibited adherence, indicating, the presence of cross-reacting antigens in adult worms and schistosomula. [ABSTRACT FROM AUTHOR]

It is believed that a T-celI helper response against the schistosome surface is a necessary prerequisite for the development of protective immunity in schistosomiasis. Accordingly, the carrier effect has been used to assay eleven antigenic preparations of Schistosoma mansoni for their helper T-cell priming against surface components of the schistosomula. Three weeks after i.v. injection of the preparation, CBA mice were injected with schistosomula coated with trinitrophenol (TNP) and 4 days later, their spleens were assayed for plaque-forming cells (PEG) against TNP. Formalin-fixed schistosomula and crude adult worm tegumental membrane induced the highest response; only thirty schistosomula or 10 μg of crude membrane protein were needed to generate a T-cell helper response equivalent to that induced by a living infection. All other antigenic preparations, including formalin-fixed cercariae, live miracidia, eggs and adult worm culture fluid, generated some response indicating the presence of shared carricr components. [ABSTRACT FROM AUTHOR]

OBJECTIVE--To assess the haemodynamic correlations of the waveforms of left ventricular area change obtained by automated boundary detection with newly developed acoustic quantification technology. DESIGN--The timing of events in the cardiac cycle was identified on the wave-form automated boundary detection and was correlated with the corresponding timing derived from pulsed wave Doppler flow velocity traces of the mitral valve and left ventricular outflow tract. The amounts of area change during the rapid filling phase and during atrial contraction were correlated with the time-velocity integrals of early and late diastolic ventricular filling obtained from Doppler tracings of the mitral inflow. SETTING--A university medical school echocardiography laboratory. SUBJECTS--16 healthy volunteers and 19 patients referred for echocardiographic studies. RESULTS--A significant correlation was found between the methods for measurement of the time from the R wave to mitral valve opening (r = 0.72, p < 0.01), isovolumic relaxation time (r = 0.62, p < 0.01), and ejection time (r = 0.54, p < 0.01). The change of total area that occurred during rapid filling and atrial filling phases measured from the acoustic waveform correlated with the time-velocity integrals of the early and late diastolic mitral valve inflow velocity derived from Doppler echocardiography (r = 0.60 and r = 0.80, respectively). CONCLUSION--The waveform of left ventricular area obtained by the automated boundary detection technique identifies the phases of the cardiac cycle and correlates with Doppler values of left ventricular diastolic function. Therefore, this new method of automated boundary detection has potential uses in the assessment of left ventricular diastolic function. [ABSTRACT FROM PUBLISHER]

OBJECTIVE--To study the time course and underlying mechanisms of right heart filling after cardiac surgery. DESIGN--A prospective observational study of adult patients undergoing cardiac surgery. SETTING--Echocardiography laboratory of the Stanford University Medical Center. PATIENTS--Twenty six patients (mean age 54.9) undergoing cardiac surgery were studied before and two days, one week, six weeks, and six months after cardiac surgery. MAIN OUTCOME MEASURES--Flow in the hepatic veins and superior vena cava, tricuspid and mitral annulus motion, signs of tricuspid regurgitation, and right ventricular size were assessed by echocardiography. RESULTS--Right heart filling, expressed as the ratio of systolic to diastolic forward flow Doppler velocity integrals in the superior vena cava and by tricuspid annulus motion, decreased in parallel from before surgery baseline values of 3.5 (SD 3.1) and 21.9 (3.4) mm, respectively to 0.2 (0.1) and 8.1 (2.3) mm two days after operation. A gradual increase towards baseline values was noted after six months, to 1.4 (1.3) and 15.1 (2.3) mm respectively; however, these values were still significantly less than those before operation. Similar changes were seen in the hepatic venous flow pattern. The decrease in total tricuspid annulus motion was most pronounced in its lateral segment and the atrial component of the tricuspid annulus motion showed similar changes. CONCLUSIONS--The pronounced decrease in tricuspid annulus motion during the early postoperative period suggests right atrial and right ventricular dysfunction as mechanisms responsible for the early changes seen. The progressive return to a normal venous filling pattern and the partial recovery of annular motion six months after operation further support the influence of the above mechanisms, as well as their resolution with time. The persistent flow abnormalities and compromised motion of the free aspects of the tricuspid annulus, however, suggest long term tethering of the right heart wall. [ABSTRACT FROM PUBLISHER]

This article presents information related to the diagnosis of patent foramen ovale (PFO). PFO is a common finding in the healthy population, with a prevalence of 27% in one necropsy study of 965 normal hearts from patients with no history of cardioembolic events. The larger size of a PFO and greater number of microbubbles passing through a shunt during echocardiography has also been associated with an increased incidence of cerebrovascular events. Transoesophageal echocardiography (TOE) is superior to transthoracic echocardiography for the diagnosis of a PFO and delineation of its morphologic details. Hence, TOE is regarded as the imaging procedure of choice in adult patients with suspected paradoxical embolism.

Background: Cardiovascular disease (CVD) is the leading cause of death around the world; however, many CVD events could be prevented if we focused on modification of the main risk factors. Increased salt consumption is estimated to have caused millions of deaths, mostly related to CVD, particularly stroke, which is the leading cause of death in Portugal. In our study, we aim to assess trends in the proportion of high blood pressure (HBP) in Acute Coronary Syndrome (ACS) patients as well as the trends in stroke and ACS in Portugal, especially after a set of public health initiatives were implemented to reduce salt intake.Methods: The monthly proportion of ACS patients presenting with previously diagnosed HBP and the monthly rate of CVD admissions into public hospitals in Portugal were calculated. CVD rates were stratified into ACS rate and stroke rates. Data were stratified by demographics variables. An interrupted time-series model was used to assess changes over time.Results: Breakpoint analysis revealed an estimated breakpoint around the year 2013 for the proportion of HBP patients, the following year there was a decreasing trend, however it was not significant. Analyses showed the trend before 2013 was increasing and started to decrease after this year. This decreased in proportion of HBP patients can be translated into a reduction of 555 people per year presenting with HBP in the ACS population. We analysed trends for ACS and stroke and tested the significance for a breakpoint in the year 2013. Although none of the remaining trends were significant for ACS crude rates and stroke crude rate, a decreasing trend was observed.Conclusions: This research provides an indication about the impact a population-wide approach to CVD risk factors has on CVD trends themselves. Our results suggest that population-wide approaches can have an impact on the prevention and improvement of CVD control, reducing the number of CVD events, and eventually reducing premature death by CVD. As more restrictions on salt intake are being planned in Portugal in the next years, it is highly relevant to assess what is the current panorama and what further reductions we can expect. [ABSTRACT FROM AUTHOR]

The article reviews the November 2011 issue of the periodical "Heart." INSET: Heart online.

The article offers the author's insights regarding the European Accreditation in Transthoracic Echocardiography in Europe. The author says that for the Working Group on Echocardiography (WGE) and European Society of Cardiology (ESC), the accreditation is an exciting moment. He states that the WGE believes that they can help in the diagnosis and treatment of cardiovascular diseases by improving the quality of, and access to cardiac ultrasound.