Extended emphysematous aortitis of the ascending aorta: An unusual fatal presentation of aortic valve endocarditis due to Clostridium Septicum.

N/A.

Prognostic values of exercise echocardiography and cardiopulmonary exercise testing in patients with primary mitral regurgitation.

AIMS: To compare the clinical significance of exercise echocardiography (ExE) and cardiopulmonary exercise testing (CPX) in patients with ≥moderate primary mitral regurgitation (MR) and discrepancy between symptoms and MR severity. METHODS AND RESULTS: Patients consulting for ≥moderate discordant primary MR prospectively underwent low (25 W) ExE, peak ExE, and CPX within 2 months in Lille and Rennes University Hospital. Patients with Class I recommendation for surgical MR correction were excluded. Changes in MR severity, systolic pulmonary artery pressure (SPAP), left ventricular ejection fraction (LVEF), and tricuspid annular plane systolic excursion were evaluated during ExE. Patients were followed for major events (ME): cardiovascular death, acute heart failure, or mitral valve surgery. Among 128 patients included, 22 presented mild-to-moderate, 61 moderate-to-severe, and 45 severe MR. Unlike MR variation, SPAP and LVEF were successfully assessed during ExE in most patients. Forty-one patients (32%) displayed reduced aerobic capacity (peak VO2 < 80% of predicted value) with cardiac limitation in 28 (68%) and muscular or respiratory limitation in the 13 others (32%). ME occurred in 61 patients (47.7%) during a mean follow-up of 27 ± 21 months. Twenty-five Watts SPAP [hazard ratio (HR) (95% confidence interval, CI) = 1.03 (1.01-1.06), P = 0.003] and reduced aerobic capacity [HR (95% CI) = 1.74 (1.03-2.95), P = 0.04] were independently predictive of ME, even after adjustment for MR severity. The cut-off of 55 mmHg for 25 W SPAP showed the best accuracy to predict ME (area under the curve = 0.60, P = 0.05). CONCLUSION: In patients with ≥moderate primary MR and discordant symptoms, 25 W exercise pulmonary hypertension, defined as an SPAP ≥55 mmHg, and poor aerobic capacity during CPX are independently associated with adverse events.

New Reference PMHS Tests to Assess Whole-Body Pedestrian Impact Using a Simplified Generic Vehicle Front-End.

This study aims to provide a set of reference post-mortem human subject tests which can be used, with easily reproducible test conditions, for developing and/or validating pedestrian dummies and computational human body models against a road vehicle. An adjustable generic buck was first developed to represent vehicle front-ends. It was composed of four components: two steel cylindrical tubes screwed on rigid supports in V-form represent the bumper and spoiler respectively, a quarter of a steel cylindrical tube represents the bonnet leading edge, and a steel plate represents the bonnet. These components were positioned differently to represent three types of vehicle profile: a sedan, a SUV and a van. Eleven post-mortem human subjects were then impacted laterally in a mid-gait stance by the bucks at 40 km/h: three tests with the sedan, five with the SUV, and three with the van. Kinematics of the subjects were recorded via high speed videos, impact forces between the subjects and the bucks were measured via load cells behind each tube, femur and tibia deformation and fractures were monitored via gauges on these bones. Based on these tests, biofidelity corridors were established in terms of: 1) displacement time history and trajectory of the head, shoulder, T1, T4, T12, sacrum, knee and ankle, 2) impact forces between the subjects and the buck. Injury outcome was established for each PMHS via autopsy. Simplicity of its geometry and use of standard steel tubes and plates for the buck will make it easy to perform future, new post-mortem human subject tests in the same conditions, or to assess dummies or computational human body models using these reference tests.

The Effect of Upper Body Mass and Initial Knee Flexion on the Injury Outcome of Post Mortem Human Subject Pedestrian Isolated Legs.

In the ECE 127 Regulation on pedestrian leg protection, as well as in the Euro NCAP test protocol, a legform impactor hits the vehicle at the speed of 40 kph. In these tests, the knee is fully extended and the leg is not coupled to the upper body. However, the typical configuration of a pedestrian impact differs since the knee is flexed during most of the gait cycle and the hip joint applies an unknown force to the femur. This study aimed at investigating the influence of the inertia of the upper body (modelled using an upper body mass fixed at the proximal end of the femur) and the initial knee flexion angle on the lower limb injury outcome. In total, 18 tests were conducted on 18 legs from 9 Post Mortem Human Subjects (PMHS). The principle of these tests was to impact the leg at 40 kph using a sled equipped with 3 crushing steel tubes, the stiffness of which were representative of the front face of a European sedan (bonnet leading edge, bumper and spoiler). The mass of the equipped sled was 74.5 kg. The test matrix was designed to perform 4 tests in 4 configurations combining two upper body masses (either 0 or 3 kg) and two knee angles (0 or 20 degrees) at 40 kph (11 m/s) plus 2 tests at 9 m/s. Autopsies were performed on the lower limbs and an injury assessment was established. The findings of this study were first that the increase of the upper body mass resulted in more severe injuries, second that an initial flexion of the knee, corresponding to its natural position during the gait cycle, decreased the severity of the injuries, and third that based on the injury outcome, a test conducted with no upper body mass and the knee fully extended was as severe as a test conducted with a 3 kg upper body mass and an initial knee flexion of 20°.

Water transport in resin-modified glass-ionomer dental cement.

Water uptake and water loss have been studied in a commercial resin-modified glass-ionomer cement, Fuji II LC, under a variety of conditions. Uptake was generally non-Fickian, but affected by temperature. At room temperature, the equilibrium water uptake values varied from 2.47 to 2.78% whereas at low temperature (12 degrees C), it varied from 0.85 to 1.18%. Cure time affected uptake values significantly. Water uptake was much lower than in conventional glass-ionomer restorative cements exposed to water vapor. Loss of water under desiccating conditions was found to be Fickian for the first 5 h loss at both 22 and 12 degrees C. Diffusion coefficients were between 0.45 and 0.76 x 10( -7) cm(2)/s, with low temperature diffusion coefficients slightly greater than those at room temperature. Plotting water loss as percentage versus s(-(1/2)) allowed activation energies to be determined from the Arrhenius equation and these were found to be 65.6, 79.8, and 7.7 kJ/mol respectively for 30, 20, and 10 s cure times. The overall conclusion is that the main advantage of incorporating HEMA into resin-modified-glass-ionomers is to alter water loss behavior. Rate of water loss and total amount lost are both reduced. Hence, resin-modified glass-ionomers are less sensitive to water loss than conventional glass-ionomers.