32 research outputs found
Ectopic Origin of a Coronary Artery from the Aorta. Sudden Death in 3 of 23 Patients.
Ectopic origin of a coronary artery from the aorta is uncommon. In the last decade, its importance as a possible cause of sudden death has been documented. Initially, only the left coronary artery was implicated. Lately, the ectopically arising right coronary artery has also been shown to be involved in cases of sudden death. We reviewed the pathologic anatomy in 23 cases of ectopic origin of a coronary artery from the aorta. In three of these cases, death could be attributed to ectopic origin of a coronary artery. In one case the left coronary artery arose from the right aortic sinus, and in two cases the right coronary artery arose from the left aortic sinus. In one of these, a scar of healed myocardial infarction was present in the inferior wall of the left ventricle. The possible mechanism for sudden death in these cases is reviewed and emphasis placed on the theory that the acute angle at which the ectopic artery leaves the aorta results in a flap-like mechanism at the arterial ostium. Ostial stenosis by the flap could be a significant factor in causing myocardial ischemia in some patients and also in sudden death
Forward production of charged pions with incident on nuclear targets measured at the CERN PS
Measurements of the double-differential production cross-section
in the range of momentum 0.5 \GeVc \leq p \le 8.0 \GeVc and angle 0.025 \rad
\leq \theta \le 0.25 \rad in interactions of charged pions on beryllium,
carbon, aluminium, copper, tin, tantalum and lead are presented. These data
represent the first experimental campaign to systematically measure forward
pion hadroproduction. The data were taken with the large acceptance HARP
detector in the T9 beam line of the CERN PS. Incident particles, impinging on a
5% nuclear interaction length target, were identified by an elaborate system of
beam detectors. The tracking and identification of the produced particles was
performed using the forward spectrometer of the HARP detector. Results are
obtained for the double-differential cross-sections mainly at four incident pion beam
momenta (3 \GeVc, 5 \GeVc, 8 \GeVc and 12 \GeVc). The measurements are compared
with the GEANT4 and MARS Monte Carlo simulationComment: to be published on Nuclear Physics
Acetaminophen (Paracetamol) Induces Hypothermia During Acute Cold Stress.
BACKGROUND
Acetaminophen is an over-the-counter drug used to treat pain and fever, but it has also been shown to reduce core temperature (T c) in the absence of fever. However, this side effect is not well examined in humans, and it is unknown if the hypothermic response to acetaminophen is exacerbated with cold exposure.
OBJECTIVE
To address this question, we mapped the thermoregulatory responses to acetaminophen and placebo administration during exposure to acute cold (10 °C) and thermal neutrality (25 °C).
METHODS
Nine healthy Caucasian males (aged 20-24 years) participated in the experiment. In a double-blind, randomised, repeated measures design, participants were passively exposed to a thermo-neutral or cold environment for 120 min, with administration of 20 mg/kg lean body mass acetaminophen or a placebo 5 min prior to exposure. T c, skin temperature (T sk), heart rate, and thermal sensation were measured every 10 min, and mean arterial pressure was recorded every 30 min. Data were analysed using linear mixed effects models. Differences in thermal sensation were analysed using a cumulative link mixed model.
RESULTS
Acetaminophen had no effect on T c in a thermo-neutral environment, but significantly reduced T c during cold exposure, compared with a placebo. T c was lower in the acetaminophen compared with the placebo condition at each 10-min interval from 80 to 120 min into the trial (all p 0.05).
CONCLUSION
This preliminary trial suggests that acetaminophen-induced hypothermia is exacerbated during cold stress. Larger scale trials seem warranted to determine if acetaminophen administration is associated with an increased risk of accidental hypothermia, particularly in vulnerable populations such as frail elderly individuals