Oh-Sang Kwon

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White matter hyperintensity (WMH) is commonly detected in patients with Alzheimer's disease (AD), but its role in cortical impairment is unclear. This study investigated the effects of WMH on gray matter (GM) volume in patients with AD. We consecutively enrolled 84 patients with AD and 35 normal controls, who underwent brain MRI and were then classified(More)
The peroxisome proliferator-activated receptors (PPARs) impart diverse cellular effects in biological systems. Because stellate cell activation during liver injury is associated with declining PPARgamma expression, we hypothesized that its expression is critical in stellate cell-mediated fibrogenesis. We therefore modulated its expression during liver(More)
BACKGROUND Low 25-hydroxyvitamin D (25(OH)D) concentrations have been shown to predict risk of cardiovascular disease and all-cause mortality. Although the prevalence of 25(OH)D deficiency is high in patients with acute stroke, the prognostic value of 25(OH)D in stroke has not been clearly established. The purpose of this study was to determine whether the(More)
Strategies of saccadic planning must take into account both the required level of accuracy of the saccades, and the time and resources needed to plan and execute the movements. To determine relationships between accuracy and time, we studied sequences of saccades made to scan a set of stationary targets located at the corners of an imaginary square. Target(More)
Despite growing evidence for perceptual interactions between motion and position, no unifying framework exists to account for these two key features of our visual experience. We show that percepts of both object position and motion derive from a common object-tracking system--a system that optimally integrates sensory signals with a realistic model of(More)
Stereopsis is the rich impression of three-dimensionality, based on binocular disparity-the differences between the two retinal images of the same world. However, a substantial proportion of the population is stereo-deficient, and relies mostly on monocular cues to judge the relative depth or distance of objects in the environment. Here we trained adults(More)
Because of uncertainty and noise, the brain should use accurate internal models of the statistics of objects in scenes to interpret sensory signals. Moreover, the brain should adapt its internal models to the statistics within local stimulus contexts. Consider the problem of hitting a baseball. The impoverished nature of the visual information available(More)
BACKGROUND Our aim was to investigate the distribution pattern of cerebral artery calcification and its association with white matter hyperintensities (WMH). METHODS We identified 159 consecutive patients with acute ischemic stroke. Calcifications of cerebral arteries and WMH were graded. RESULTS Cerebral artery calcification was found in 137 patients(More)
BACKGROUND AND AIMS Elevated serum homocysteine level is known to be associated with increased risk of vascular event due to endothelial senescence. We investigated the association between serum homocysteine level and cerebral arteriosclerosis status including intracranial vascular calcification and atherosclerosis burden. METHODS We identified 1193(More)