903 research outputs found

    Inflammation and Atherosclerosis: State of the Art in 2004-2005

    Full text link
    peer reviewedInflammation plays a pivotal role in atherosclerosis; being present in all steps of the pathology, from initiation to the progression of the lesions to the development of vulnerable plaques and clinical destabilisation. Therefore, systemic markers of inflammation have emerged to predict future cardiovascular events in patients initially admitted for unstable syndromes, but also in healthy subjects. These markers can identify high risk patients and they are used to adapt ideal treatment to the patient's profile. The implication of the inflammation process in the treatment strategies is described in the last part of the article

    Evaluating self-attention interpretability through human-grounded experimental protocol

    Full text link
    Attention mechanisms have played a crucial role in the development of complex architectures such as Transformers in natural language processing. However, Transformers remain hard to interpret and are considered as black-boxes. This paper aims to assess how attention coefficients from Transformers can help in providing interpretability. A new attention-based interpretability method called CLaSsification-Attention (CLS-A) is proposed. CLS-A computes an interpretability score for each word based on the attention coefficient distribution related to the part specific to the classification task within the Transformer architecture. A human-grounded experiment is conducted to evaluate and compare CLS-A to other interpretability methods. The experimental protocol relies on the capacity of an interpretability method to provide explanation in line with human reasoning. Experiment design includes measuring reaction times and correct response rates by human subjects. CLS-A performs comparably to usual interpretability methods regarding average participant reaction time and accuracy. The lower computational cost of CLS-A compared to other interpretability methods and its availability by design within the classifier make it particularly interesting. Data analysis also highlights the link between the probability score of a classifier prediction and adequate explanations. Finally, our work confirms the relevancy of the use of CLS-A and shows to which extent self-attention contains rich information to explain Transformer classifiers.Comment: 11 pages, 7 figure

    New Therapeutic Guidelines in Cardiology

    Full text link
    peer reviewedCardiovascular diseases are the leading cause of mortality in the so-called industrial countries. An appropriate management is mandatory and its modalities should be known and applied by physicians. European and American recommendations are regularly published and updated. They are available on the web sites of the European Society of Cardiology (www.escardio.org), the American Heart Association (www.aha.org) and the American College of Cardiology (www.acc.org This article describes the recent therapeutic options of some cardiovascular diseases, especially coronary artery disease, valvular diseases, atrial fibrillation and implantable defibrillator, but is far to be exhaustive

    Temporal variations of non-volcanic tremor (NVT) locations in the Mexican subduction zone: Finding the NVT sweet spot.

    Get PDF
    International audienceEpicentral locations of non-volcanic tremors (NVT) in the Mexican subduction zone are determined from the peak of the energy spatial distribution and examined over time. NVT is found to occur persistently at a distance of ∼215 km from the trench, which we term the "Sweet Spot" because this region probably has the proper conditions (i.e., temperature, pressure, and fluid content) for the NVT to occur with minimum shear slip. High-energy NVT episodes are also observed every few months, extending ∼190 km to ∼220 km from the trench with durations of a few weeks. During the 2006 slow slip event (SSE) the duration and the recurrence rate of the NVT episodes increased. Low-energy episodes were also observed, independent from the high-energy episodes, ∼150 km to ∼190 km from the trench during the 2006 SSE. Both the high and low energy episodes were made up of many individual NVT's that had a range of energy-release-rates. However, the highest energy-release-rates of the high-energy episodes were consistently double those of the low-energy episodes and the persistent activity at the Sweet Spot. We suggest that all of the high-energy episodes are evidence of small, short repeat interval SSE. Given this model, the increased recurrence rate of the high-energy NVT episodes during the 2006 long-term SSE implies that short-term SSE's also increase during the SSE and are therefore triggered by the SSE

    Comparative long-term effects of coronary artery bypass graft surgery and percutaneous transluminal coronary angioplasty on regional coronary flow reserve.

    Full text link
    peer reviewedTo evaluate the relative long-term improvement in coronary artery hemodynamics after revascularization by coronary artery bypass graft surgery (CABG) or percutaneous transluminal coronary angioplasty (PTCA), regional coronary flow reserve (CFR) was measured, by digital computer analysis of 35 mm cine film, in 50 men undergoing cardiac catheterization. CFR (mean +/- SEM) in 12 atherosclerotic arteries before revascularization was 1.02 +/- 0.05. Mean CFR in 29 normal arteries of men with normal coronary arteriograms was significantly higher (2.59 +/- 0.11) than that in 16 atherosclerotic arteries of patients revascularized by CABG (2.02 +/- 0.17, p less than .01) or in 14 atherosclerotic arteries of those revascularized by PTCA (1.97 +/- 0.12, p less than .01). No difference in CFR between the CABG and PTCA groups was found and variables known to influence CFR were similar between groups. Equivalent and significant long-term improvement in coronary artery hemodynamics is provided by CABG or PTCA. We postulate that the difference in CFR in the men with normal arteries and those who underwent revascularization was related to the effects of the general atherosclerotic process, which remain despite successful treatment by these techniques

    Evolution of coronary atherosclerosis in patients with mild coronary artery disease studied by serial quantitative coronary angiography at 2 and 4 years follow up

    Get PDF
    AIMS: Angiographic studies on the natural course of both focal and diffuse coronary atherosclerosis have not been performed before, but can both be assessed by quantitative coronary angiography. The objective of this study was to describe the natural course of focal and diffuse coronary atherosclerosis over time. METHODS AND RESULTS: In 129 patients with mild coronary artery disease, but not on lipid-lowering medication, three coronary angiograms were made each 2 years apart. Nine hundred and sixty five angiographically diseased and non-diseased segments were analysed by quantitative coronary angiography. Mean lumen diameter and minimal lumen diameter were used as measures of diffuse and focal coronary atherosclerosis. Mean lumen diameter and minimum lumen diameter decreased by 0.02 and 0.03 mm per year. The rate of progression was similar in the angiographically non-diseased, as in the mildly and moderately diseased segments. Progression of diffuse coronary atherosclerosis was largest in severely stenosed lesions (percentage diameter stenosis > or = 50%) and in the right coronary artery with a loss of 0.19 mm and 0.16 mm in mean lumen diameter. Progression of focal disease was most prominent in new and mild lesions and the right coronary artery, with a decrease in minimum lumen diameter of 0.34 mm and 0.22 mm. In most subgroups, progression occurred gradually over time. On a per segment level, progression and the occurrence of new lesions occurred in 4.4% and 4.2%. Regression and disappearance of a lesions was found in 2.3% and 1.9%. On a per patient level, 36% were progressors, 12% had a mixed response, 36% were stable, and 16% were regressors. CONCLUSION: Diffuse and focal coronary atherosclerosis progressed at the same rate in the first and second 2 years in stenosed and non-stenosed segments. The rate of coronary atherosclerosis progression was small, but was higher for focal than for diffuse disease. A minority of lesions progressed and spontaneous regression was rare

    Influence of age on the clinical outcomes of coronary revascularisation for the treatment of patients with multivessel de novo coronary artery lesions: sirolimus-eluting stent vs. coronary artery bypass surgery and bare metal stent, insight from the multicentre randomised Arterial Revascularisation Therapy Study Part I (ARTS-I) and Part II (ARTS-II)

    Full text link
    peer reviewedAims: We sought to evaluate the prognostic impact of age on the procedural results and subsequent clinical outcomes in patients with multivessel disease (MVD) treated either by coronary artery bypass surgery (CABG) or by percutaneous coronary intervention (PCI) with or without drug eluting stents, based on data of the Arterial Revascularisation Therapies Study (ARTS) part I and part II. The potential influence of age in determining the most appropriate revascularisation strategy for patients with MVD is largely unknown. Methods and results: Three year clinical outcome of ARTS I patients randomised to PCI with bare metal stent (BMS) (n= 600) or CABG (n= 605), and matched patients treated by PCI with sirolimus-eluting stents (SES) in ARTS II (n= 607) were reviewed according to four age quartiles. Endpoints were measured in terms of major adverse cardiac and cerebrovascular events MACCE) during hospital stay and up to three years. The frequency of female, diabetes, hypertension, peripheral vascular disease, pulmonary disease, as well as lesion complexity increased with age. At three years, MACCE free survival was comparable between patients treated by CABG or SES PCI, regardless of age quartile. The incidence of MACCE was higher among ARTS I BMS treated patients in all but the second age quartile. This was primarily related to a higher need for repeat revascularisation among BMS treated patients. However, age, which emerged as a strong independent predictor of MACCE following CABG (p<0.005), was not predictive of adverse events following PCI. Conversely, diabetes was the strongest independent predictor of MACCE among PCI treated patients (p<0.02), but didn’t affect three-year outcomes following CABG. Conclusions: Age seems to influence the CABG outcome in-hospital but not PCI. PCI-SES could offer lower immediate risk in patients with MVD and comparable long-term outcome as CABG especially in older patients. The worst outcome of PCI-BMS group is primarily related to the need for repeat revascularisation. Diabetes is the most important predictor of MACCE following PCI

    Evidence of abnormal vasodilator reserve in coronary spasm

    Full text link
    Although reduction of coronary flow reserve (CFR) is a common consequence of significant coronary stenoses, recent observations suggest that it may also be abnormal in other clinical settings such as myocardial hypertrophy or syndrome X in the absence of stenoses.1,2 This report shows that the CFR may also be abnormal in patients with normal coronary arteries and vasospasm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26259/1/0000340.pd

    New Data on the Genesis and Evolution of the Primitive Magmas of Mount Cameroon: Contribution of Melt Inclusions

    Get PDF
    Mount Cameroon is a Plio-Quaternary volcanic massif, without a centralcrater, made up of more than 140 pyroclastic cones. It is one of theactive volcanoes of the Cameroon Volcanic Line. Mount Cameroon meltinclusions are found in microdroplets trapped in the early minerals (olivines)from the pyroclastic products. The analysis of these melt inclusions allowedus to find primitive liquids compared to lavas. Major elements study ofthe magmatic inclusions, trapped in the most magnesian olivines (Mg#84-86) of Mount Cameroon revealed “primitive” liquids of basanite and alkalibasalt type with variable composition compared to the much more uniformbasalts of the magmatic series of Mount Cameroon. The study of thesetrapped liquids shows that: (1) the original primitive lavas did not undergothe process of evolution by FC, but rather underwent fundamentally (orexclusively) the process of partial melting; (2) the emitted lavas, evolvedessentially by FC; (3) the variations in the trace element contents of theprimitive liquids directly reflect a variation in the rate of partial melting ofa homogeneous mantelic source. The very high La/Yb ratios of the MountCameroon melt inclusions (> 20) characterize a garnet lherzolite source.Spectra of the melt inclusions show a negative anomaly or depletion in K,Rb and Ba as those of HIMU. The “primitive” liquids and lavas of MountCameroon represent a co-genetic sequence formed by varying degrees ofpartial melting of a source considered as homogeneous

    Quantitative assessment of global and regional left ventricular function with low-contrast dose digital subtraction ventriculography.

    Full text link
    Few studies have compared the use of low-contrast dose digital subtraction ventriculography with conventional ventriculography for quantitative assessment of both global and regional left ventricular function. Accordingly, 34 patients underwent conventional ventriculography using 36 ml of ionic contrast material and digital ventriculography (mask-mode) using 10 ml of contrast diluted in 10 ml of saline and injected over two seconds. Data from two patients were excluded because of ectopy during cineventriculography and from one because of ectopy during both studies. End-diastolic and end-systolic volumes were calculated from both studies by an area-length method and used to calculate ejection fractions. Regional wall motion was quantitated by the centerline method. Results of linear regression analysis demonstrated high correlations for all parameters (end-diastolic volume, r = 0.85; end-systolic volume, r = 0.93; ejection fraction, r = 0.92; quantitative regional wall motion, r = 0.90). Thus, low-contrast dose digital subtraction ventriculography provides an accurate assessment of both global and regional ventricular function and minimizes the required dose and inherent risks of contrast media
    corecore