Your search for: 'author:("Kim, Jeong Hwan")' has returned 3 results. (0.013s) Save search

Authors: Shin, Seung-Won | Kim, Kyeong-Seop | Song, Chul-Gyu | Lee, Jeong-Whan | Kim, Jeong-Hwan | Jeung, Gyeo-Wun

Article Type: Research Article

Abstract: The very first step to process electrocardiogram (ECG) signal is to eliminate baseline wandering interference that is usually caused by electrode-skin impedance mismatch, motion artifacts due to a patient’s body moment or respiratory breathing. A new method is thus suggested to remove baseline wandering in ECG by improving the detrending method that was originally proposed for eliminating slow non-stationary trends from heart rate variability (HRV). In our proposed method, a global trend is estimated in terms of baseline wandering by merging the local trend based on an ECG segment that represents a part of the ECG signal. The experimental results …show that the improved detrending method can efficiently resolve baseline wandering without distorting any morphological characteristic embedded in the ECG signal in no time delay manner. Show more

Keywords: Electrocardiogram (ECG), baseline wandering, detrending, heart rate variability (HRV), high-pass filter

DOI: 10.3233/BME-151405

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S1087-S1093, 2015

Authors: Moazzami, Kasra | Wittbrodt, Matthew T. | Lima, Bruno B. | Kim, Jeong Hwan | Almuwaqqat, Zakaria | Shah, Amit J. | Hajjar, Ihab | Goldstein, Felicia C. | Levey, Allan I. | Nye, Jonathon A. | Bremner, J. Douglas | Vaccarino, Viola | Quyyumi, Arshed A.

Article Type: Research Article

Abstract: Background: Individuals with coronary artery disease (CAD) have worse executive function compared to the general population but the mechanisms are unknown. Objective: To investigate the role of acute mental stress (MS) on the executive function of patients with CAD. Methods: Participants with stable CAD underwent acute MS testing with simultaneous peripheral vascular function measurements and brain imaging using high resolution-positron emission tomography. Digital pulse wave amplitude was continuously measured using peripheral artery tonometry (PAT, Itamar Inc). Stress/rest PAT ratio (sPAT) of pulse wave amplitude during MS/baseline was calculated as a measure of microvascular constriction during MS. Plasma levels of catecholamine …and interleukin-6 were assessed at baseline and after MS. Executive function was assessed both at baseline and at 2 years follow-up using the Trail Making Test parts A and B. Results: We studied 389 individuals with brain data available for 148 participants. Of this population follow-up cognitive assessments were performed in 226 individuals (121 with brain imaging). After multivariable adjustment for baseline demographics, risk factors, and medication use, a lower sPAT, indicating greater vasoconstriction, a higher inferior frontal lobe activation with MS, and increases in norepinephrine and IL-6 levels with MS were all independently associated with greater time to complete Trail B test.-38.4pt Conclusion: In response to acute MS, greater peripheral vasoconstriction, higher inferior frontal lobe brain activation, and increases in the levels of norepinephrine and IL-6 are associated with worse executive function. Show more

Keywords: Brain activation, cognitive impairment, mental stress, vasoconstriction

DOI: 10.3233/ADR-200287

Citation: Journal of Alzheimer's Disease Reports, vol. 5, no. 1, pp. 99-109, 2021

Authors: Moazzami, Kasra | Wittbrodt, Matthew T. | Lima, Bruno B. | Kim, Jeong Hwan | Hammadah, Muhammad | Ko, Yi-An | Obideen, Malik | Abdelhadi, Naser | Kaseer, Belal | Gafeer, M. Mazen | Nye, Jonathon A. | Shah, Amit J. | Ward, Laura | Raggi, Paolo | Waller, Edmund K. | Bremner, J. Douglas | Quyyumi, Arshed A. | Vaccarino, Viola

Article Type: Research Article

Abstract: Background: Circulating progenitor cells (CPC) have been associated with memory function and cognitive impairment in healthy adults. However, it is unclear whether such associations also exist in patients with coronary artery disease (CAD). Objective: To assess the association between CPCs and memory performance among individuals with CAD. Methods: We assessed cognitive function in 509 patients with CAD using the verbal and visual Memory subtests of the Wechsler memory scale-IV and the Trail Making Test parts A and B. CPCs were enumerated with flow cytometry as CD45med /CD34+ blood mononuclear cells, those co-expressing other epitopes representing populations enriched for hematopoietic and …endothelial progenitors. Results: After adjusting for demographic and cardiovascular risk factors, lower number of endothelial progenitor cell counts were independently associated with lower visual and verbal memory scores (p for all < 0.05). There was a significant interaction in the magnitude of this association with race (p  < 0.01), such that the association of verbal memory scores with endothelial progenitor subsets was present in Black but not in non-Black participants. No associations were present with the hematopoietic progenitor-enriched cells or with the Trail Making Tests. Conclusion: Lower numbers of circulating endothelial progenitor cells are associated with cognitive impairment in patients with CAD, suggesting a protective effect of repair/regeneration processes in the maintenance of cognitive status. Impairment of verbal memory function was more strongly associated with lower CPC counts in Black compared to non-Black participants with CAD. Whether strategies designed to improve regenerative capacity will improve cognition needs further study. Show more

Keywords: Circulating progenitor cells, cognitive impairment, coronary artery disease, dementia, memory, trail making tests, Wechsler Memory Scale

DOI: 10.3233/JAD-191063

Citation: Journal of Alzheimer's Disease, vol. 74, no. 2, pp. 659-668, 2020