• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.133-153
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• 2023

In this paper, we propose a novel approach to investigating brain-signal measurement technology using Electroencephalography (EEG). Traditionally, researchers have combined EEG signals with bio-signals (BSs) to enhance the classification performance of emotional states. Our objective was to explore the synergistic effects of coupling EEG and BSs, and determine whether the combination of EEG+BS improves the classification accuracy of emotional states compared to using EEG alone or combining EEG with pseudo-random signals (PS) generated arbitrarily by random generators. Employing four feature extraction methods, we examined four combinations: EEG alone, EG+BS, EEG+BS+PS, and EEG+PS, utilizing data from two widely-used open datasets. Emotional states (task versus rest states) were classified using Support Vector Machine (SVM) and Long Short-Term Memory (LSTM) classifiers. Our results revealed that when using the highest accuracy SVM-FFT, the average error rates of EEG+BS were 4.7% and 6.5% higher than those of EEG+PS and EEG alone, respectively. We also conducted a thorough analysis of EEG+BS by combining numerous PSs. The error rate of EEG+BS+PS displayed a V-shaped curve, initially decreasing due to the deep double descent phenomenon, followed by an increase attributed to the curse of dimensionality. Consequently, our findings suggest that the combination of EEG+BS may not always yield promising classification performance.

• BMB Reports
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• v.43 no.10
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• pp.704-709
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• 2010

The Swedish mutation (K595N/M596L) of amyloid precursor protein (APP-swe) has been known to increase abnormal cleavage of cellular APP by Beta-secretase (BACE), which causes tau protein hyperphosphorylation and early-onset Alzheimer's disease (AD). Here, we analyzed the effect of APP-swe in global gene expression using deep transcriptome sequencing technique. We found 283 genes were down-regulated and 348 genes were up-regulated in APP-swe expressing H4-swe cells compared to H4 wild-type cells from a total of approximately 74 million reads of 38 base pairs from each transcriptome. Two independent mechanisms such as kinase and phosphatase signaling cascades leading hyperphosphorylation of tau protein were regulated by the expression of APP-swe. Expressions of catalytic subunit as well as several regulatory subunits of protein phosphatases 2A were decreased. In contrast, expressions of tau-phosphorylating glycogen synthase kinase $3\beta$(GSK-3$\beta$), cyclin dependent kinase 5 (CDK5), and cAMP-dependent protein kinase A (PKA) catalytic subunit were increased. Moreover, the expression of AD-related Aquaporin 1 and presenilin 2 expression was regulated by APP-swe. Taken together, we propose that the expression of APP-swe modulates global gene expression directed to AD pathogenesis.

• Journal of Korean Neurosurgical Society
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• v.53 no.4
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• pp.235-240
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• 2013

Fusiform aneurysms on the basilar artery (BA) trunk are rare. The microsurgical management of these aneurysms is difficult because of their deep location, dense collection of vital cranial nerves, and perforating arteries to the brain stem. Endovascular treatment is relatively easier and safer compared with microsurgical treatment. Selective occlusion of the aneurysmal sac with preservation of the parent artery is the endovascular treatment of choice. But, some cases, particularly giant or fusiform aneurysms, are unsuitable for selective sac occlusion. Therefore, endovascular coiling of the aneurysm with parent vessel occlusion is an alternative treatment option. In this situation, it is important to determine whether a patient can tolerate parent vessel occlusion without developing neurological deficits. We report a rare case of fusiform aneurysms in the BA trunk. An 18-year-old female suffered a headache for 2 weeks. Computed tomography and magnetic resonance image revealed a fusiform aneurysm of the lower basilar artery trunk. Digital subtraction angiography revealed a $7.1{\times}11.0$ mm-sized fusiform aneurysm located between vertebrovasilar junction and the anterior inferior cerebellar arteries. We had good clinical result using endovascular coiling of unruptured fusiform aneurysm on the lower BA trunk with parent vessel occlusion after confirming the tolerance of the patient by balloon test occlusion with induced hypotension and accompanied by neurophysiologic monitoring, transcranial Doppler and single photon emission computed tomography. In this study, we discuss the importance of preoperative meticulous studies for avoidance of delayed neurological deficit in the patient with fusiform aneurysm on lower basilar trunk.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.1
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• pp.129-140
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• 2017

In this paper, a $4{\times}32$-channel neural recording system capable of acquiring neural signals is introduced. Four 32-channel neural recording ICs, complex programmable logic devices (CPLDs), a micro controller unit (MCU) with USB interface, and a PC are used. Each neural recording IC, implemented in $0.18{\mu}m$ CMOS technology, includes 32 channels of analog front-ends (AFEs), a 32-to-1 analog multiplexer, and an analog-to-digital converter (ADC). The mid-band gain of the AFE is adjustable in four steps, and have a tunable bandwidth. The AFE has a mid-band gain of 54.5 dB to 65.7 dB and a bandwidth of 35.3 Hz to 5.8 kHz. The high-pass cutoff frequency of the AFE varies from 18.6 Hz to 154.7 Hz. The input-referred noise (IRN) of the AFE is $10.2{\mu}V_{rms}$. A high-resolution, low-power ADC with a high conversion speed achieves a signal-to-noise and distortion ratio (SNDR) of 50.63 dB and a spurious-free dynamic range (SFDR) of 63.88 dB, at a sampling-rate of 2.5 MS/s. The effectiveness of our neural recording system is validated in in-vivo recording of the primary somatosensory cortex of a rat.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.239-246
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• 1999

Hyperhomocysteinemia is an independent risk factor for cardiovascular, cerebrovascular and peripheral vascular diseases complicated with atherosclerosis and thromboembolism. Increased plasma homocystein level develops from genetic defect of enzyme for homocystein metabolism or vitamine deficiency, has direct toxic effect for vascular endothelium and makes damages to antithrombotic action of vascular endothelial cell. Most of hyperhomocysteinemia is asymptomatic, but rarely develops cardiopulmonary or cerebrovascular accidents. In case of thromboembolism with unknown cause, the hyperhomocysteinemia should be considered as one of the many etiologies. The authors, first in korea, report a case of multiple thromboembolisms of deep vein of lower extremity, pulmonary vessels, superior sagittal and transverse sinus of brain in a patient with the hyperhomocysteinemia with a review of literature.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.157-160
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• 2002

The dosage of intra-operative BNCT using near-threshold $^{7}$ Li(p,n)$^{7}$ Be direct neutrons was evaluated with the calculation method validated with the phantom experiment. The production of both neutrons by near-threshold $^{7}$ Li(p,n)$^{7}$ Be and gamma rays by $^{7}$ Li(p,p'gamma)$^{7}$ Li in a Li target was calculated using Lee's method and their transport in the phantom was calculated with MCNP-4B. As a result, the region satisfying the requirements of the protocol in intra-operative BNCT for brain tumors in Japan was acknowledged to be comparable to present BNCT, for the proton energy of 1.900 MeV for example. A boron-dose enhancer (BDE) introduced in this study to increase $^{10}$ (n,$\alpha$)$^{7}$ Li dose in a living body was effective. The void used to increase doses in deep regions was also valid with the BDE. It was found that intra-operative BNCT using near-threshold $^{7}$ Li(p,n)$^{7}$ Be direct neutrons is feasible.

• Journal of Chest Surgery
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• v.34 no.7
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• pp.547-551
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• 2001

The effects of deep hypothermia and circulatory arrest during aortic arch reconstruction are associated with potential neurologic and myocardial injury. We describe a surgical technique that two patients underwent a modified Norwood procedure without circulatory arrest and myocardial ischemia. One was 13-day-old female patient, weighing 3.1kg, having a variant of hypoplastic left heart syndrome and another was 38-day-old male patient, weighing 3.4 kg, diagnosed Taussig-Bing anomaly with severe aortic arch hypoplasia, coarctation of the aorta, and subaortic stenosis. The arterial cannula was inserted in innominate artery directly. During Norwood reconstruction, regional high-flow perfusion into the inominate artery and coronary perfusion were maintained and there were no neurologic, cardiac, and renal complications in two patients. This technique may help protect the brain and myocardium from ischemic injury in patients with hypoplastic left heart syndrome or other arch anomalies including coarctation or interruption.

• Journal of Chest Surgery
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• v.44 no.5
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• pp.343-347
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• 2011

Background: Acute pulmonary thromboembolism is fatal because of abruptly occurring hypoxemia and right ventricular failure. There are several treatment modalities, including anticoagulation, thrombolytics, ECMO (extracorporeal membrane oxygenator), and thromboembolectomy, for managing acute pulmonary thromboembolism. Materials and Methods: Medical records from January 1999 to December 2004 at our institution were retrospectively reviewed for pulmonary thromboembolectomy. There were 7 patients (4 men and 3 women), who underwent a total of 8 operations because one patient had post-operative recurrent emboli and underwent reoperation. Surgery was indicated for mild hypoxemia and performed with CPB (cardiopulmonary bypass) in a beating heart state. Results: The patients had several symptoms, such as dyspnea, chest discomfort, and palpitation. Four patients had deep vein thromboembolisms and 3 had psychotic problems, specifically schizophrenia. Post-operative complications included hemothorax, pleural effusion, and pericardial effusion. There were two hospital deaths, one each by brain death and right heart failure. Conclusion: Emergency operation should be performed when medical treatments are no longer effective.

• Archives of Craniofacial Surgery
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• v.12 no.1
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• pp.63-66
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• 2011

Purpose: Cranial fasciitis is a rare type of benign tumor that occurs mostly in children younger than 6 years. It arises from the deep fascia, periosteum, or fibromembranous layer that covers fontanelles. The etiology is unknown, although prior trauma has been postulated to be an underlying cause. There is a 2:1 male predominance. Despite its rapid growth, this tumor has a benign clinical course and can be cured by total excision. Methods: A 16-year-old male presented with a 3 cm-sized palpable mass in the left lateral eyebrow region that he first noticed 4 months before presentation. The mass had grown rapidly since it was first noticed. Preoperative brain computed tomography showed a well-demarcated mass approximately 3 cm in size extending from the subcutaneous layer to the periosteum. Preoperatively, the presumed diagnosis was a dermoid cyst. An operation was performed with the patient under general anesthesia. The subcutaneous mass was completely excised by periosteal dissection. Results: Histological diagnosis revealed the presence of cranial fasciitis. After 20 months of follow-up, there have been neither complications nor evidence of local recurrence besed on clinical examination. Conclusion: Although cranial fasciitis is quite rare, it should be considered in the differential diagnosis for lytic skull lesions in patient whose clinical presentation suggests this possibility. This condition could be occasionally mistaken for malignant or locally aggressive lesions. To prevent local recurrence, curettage of the underlying bone is recommended for patients with bone involvement.

• Korean Journal of Health Education and Promotion
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• v.35 no.5
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• pp.17-24
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• 2018

Objectives: After many national physical activity guidelines have established, recent changes are deep and rapid. So the major features and implication to reverse worsening Korean physical activity indicator is desprate but related knowledge and informations are few. So review of recent features and implications of new physical activity guidelines have made. Methods: National physical activity guidelines of advanced countries were searched through snowballing methods. Major features were described according to the nation. Implication were drew through discussion for Korean realitiy. Results: New Australian physical activity and sedentary behaviour guideline explicitly included sedentary behaviour. The age in the guideline expanded to early years. Canada also presented 24-hour movement guidelines to early years. The second generation of the physical activity guidelines reflects the extensive amount of new knowledge. New aspects include discussions of additional health benefits related to brain health, additional cancer sites, and fall-related injuries; immediate and longer term benefits for how people feel, function, and sleep; further benefits among older adults and people with additional chronic conditions; risks of sedentary behavior and their relationship with physical activity; elimination of the requirement for physical activity benefits to occur in bouts of at least 10 minutes; and tested strategies that can be used to get the population more active. Conclusions: The most important message from the new guidelines is that the greatest health benefits accrue by moving from no, to even small amounts of, physical activity. Multiple studies demonstrate that the steepest reduction in disease risk occurs at the lowest levels of physical activity. People need to understand that even small amounts of physical activity are beneficial and that reductions in the risk of disease and disability occur by simply getting moving. So various evidence based proven strstegies are needed in Korea including workforce training.