181 research outputs found
Risk Factors for In-hospital Nonhemorrhagic Stroke in Patients With Acute Myocardial Infarction Treated With Thrombolysis: Results from GUSTO-I
BACKGROUND: Nonhemorrhagic stroke occurs in 0.1% to 1.3% of patients with
acute myocardial infarction who are treated with thrombolysis, with
substantial associated mortality and morbidity. Little is known about the
risk factors for its occurrence. METHODS AND RESULTS: We studied the 247
patients with nonhemorrhagic stroke who were randomly assigned to one of
four thrombolytic regimens within 6 hours of symptom onset in the GUSTO-I
trial. We assessed the univariable and multivariable baseline risk factors
for nonhemorrhagic stroke and created a scoring nomogram from the baseline
multivariable modeling. We used time-dependent Cox modeling to determine
multivariable in-hospital predictors of nonhemorrhagic stroke. Baseline
and in-hospital predictors were then combined to determine the overall
predictors of nonhemorrhagic stroke. Of the 247 patients, 42 (17%) died
and another 98 (40%) were disabled by 30-day follow-up. Older age was the
most important baseline clinical predictor of nonhemorrhagic stroke,
followed by higher heart rate, history of stroke or transient ischemic
attack, diabetes, previous angina, and history of hypertension. These
factors remained statistically significant predictors in the combined
model, along with worse Killip class, coronary angiography, bypass
surgery, and atrial fibrillation/flutter. CONCLUSIONS: Nonhemorrhagic
stroke is a serious event in patients with acute myocardial infarction who
are treated with thrombolytic, antithrombin, and antiplatelet therapy. We
developed a simple nomogram that can predict the risk of nonhemorrhagic
stroke on the basis of baseline clinical characteristics. Prophylactic
anticoagulation may be an important treatment strategy for patients with
high probability for nonhemorrhagic stroke, but further study is needed
Stroke in Patients With Acute Coronary Syndromes: Incidence and Outcomes in the Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) Trial
BACKGROUND: The incidence of stroke in patients with acute coronary
syndromes has not been clearly defined because few trials in this patient
population have been large enough to provide stable estimates of stroke
rates. METHODS AND RESULTS: We studied the 10 948 patients with acute
coronary syndromes without persistent ST-segment elevation who were
randomly assigned to placebo or the platelet glycoprotein IIb/IIIa
receptor inhibitor eptifibatide in the Platelet Glycoprotein IIb/IIIa in
Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT)
trial to determine stroke rates, stroke types, clinical outcomes in
patients with stroke, and independent baseline clinical predictors for
nonhemorrhagic stroke. Stroke occurred in 79 (0.7%) patients, with 66
(0.6%) nonhemorrhagic, 6 intracranial hemorrhages, 3 cerebral infarctions
with hemorrhagic conversion, and 4 of uncertain cause. There were no
differences in stroke rates between patients who received placebo and
those assigned high-dose eptifibatide (odds ratios and 95% confidence
intervals 0.82 [0.59, 1.14] and 0.70 [0.49, 0.99], respectively). Of the
79 patients with stroke, 17 (22%) died within 30 days, and another 26
(32%) were disabled by hospital discharge or 30 days, whichever came
first. Higher heart rate was the most important baseline clinical
predictor of nonhemorrhagic stroke, followed by older age, prior anterior
myocardial infarction, prior stroke or transient ischemic attack, and
diabetes mellitus. These factors were used to develop a simple scoring
nomogram that can predict the risk of nonhemorrhagic stroke. CONCLUSIONS:
Stro
A review of spatial causal inference methods for environmental and epidemiological applications
The scientific rigor and computational methods of causal inference have had
great impacts on many disciplines, but have only recently begun to take hold in
spatial applications. Spatial casual inference poses analytic challenges due to
complex correlation structures and interference between the treatment at one
location and the outcomes at others. In this paper, we review the current
literature on spatial causal inference and identify areas of future work. We
first discuss methods that exploit spatial structure to account for unmeasured
confounding variables. We then discuss causal analysis in the presence of
spatial interference including several common assumptions used to reduce the
complexity of the interference patterns under consideration. These methods are
extended to the spatiotemporal case where we compare and contrast the potential
outcomes framework with Granger causality, and to geostatistical analyses
involving spatial random fields of treatments and responses. The methods are
introduced in the context of observational environmental and epidemiological
studies, and are compared using both a simulation study and analysis of the
effect of ambient air pollution on COVID-19 mortality rate. Code to implement
many of the methods using the popular Bayesian software OpenBUGS is provided
Campilobacteriose genital bovina e tricomonose genital bovina: epidemiologia, diagnóstico e controle
Highly-parallelized simulation of a pixelated LArTPC on a GPU
The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype
- …