• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.451-454
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• 1997

It has been reported that sudden cardiac death and ventricular tachycardia occur after treatment of tetralogy of fallot(TOF). It is regarded that ventricular arrythmia is the main source or the sudden cardiac death, but it is not verified. It is likely that TOF has effect on the heart rate variability because of the ventricular arrythmia. We study how complex and periodic heart rate dynamics change in the normal children (n=13) and TOF children (n=13) throughout 24 hours. We recorded 24-hour holter ECG, and segmented each ECG data into 1 hour length. We analyze each HR time series, and quantify the overall complexity of each HR time series by its correlation dimension. We also calculate the power spectrum of HR, and obtain low-frequency component (0.03-0.15Hz) and high-frequency component (0.15-0.4Hz). We compare the results between normal and TOF groups throughout 24 hours. TOF group have lower correlation dimension ($4.055{\pm}0.4134$ vs. $4.9310{\pm}0.2054$, p<0.05) than the normal group, even though there are no significant differences in the low($0.9864{\pm}0.5598$ vs. $1.5560{\pm}0.8325$, p<0.05) and high($1.1168{\pm}0.1.1448$ vs. $0.9271{\pm}0.6528$, p<0.05) frequency components. It can be concluded that HR time series of TOF group are more regular than that of normal group, and that correlation dimension reveals a nonlinear characteristics of HR time series which is not determined in the frequency domain.

• Journal of Korean Neurosurgical Society
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• 제64권5호
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• pp.726-731
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• 2021

Objective : Distinguishing between an infundibulum and a true aneurysm is clinically important. This study aimed to evaluate whether using source image based new three-dimensional rotational angiography (S-n3DRA) can increase the rate of aneurysm detection and improve distinction between a true aneurysm and an infundibulum. Methods : Twenty-two consecutive patients with 23 lesions, were evaluated by time-of-flight (TOF) magnetic resonance angiography (MRA), S-n3DRA, and digital subtraction angiography (DSA). The data were retrospectively and independently reviewed by two neurointerventionists, and the diagnoses based on TOF MRA, S-n3DRA, and DSA were compared. The diagnostic efficacy (interobserver agreement and diagnostic performance) of S-n3DRA was compared with that of TOF MRA. Results : S-n3DRA showed higher interobserver agreement (κ=0.923) than TOF MRA (κ=0.465) and significantly higher accuracy than MRA in distinguishing an aneurysm from an infundibulum (p=0.0039). Conclusion : Compared to MRA, S-n3DRA could provide better screening accuracy and information for distinguishing an aneurysm from an infundibulum. Therefore, S-n3DRA has the potential to reduce the need for DSA.

• Elastomers and Composites
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• 제39권2호
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• pp.153-160
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• 2004

풀러렌($C_{70}$)을 3-picoline N-oxide, pyridine N-oxide hydrate, quinoline N-oxide, isoquinolne N-oxide의 여러가지 아민 N-옥시드를 사용하여 $25{\sim}43^{\circ}C$, 초음파 조건에서 반응시켜 풀러렌 산화물을 합성 하였다. 동일한 초음파 조건에서 여러가지 아민 N-옥시드에 대한 풀러렌 ($C_{70}$)의 반응성은 3-picoline N-oxide : pyridine N-oxide hydrate : quinoline N-oxide : isoquinoline N-oxide 처럼 동일하게 나타났다. MALDI -TOF MS, UV-vis 그리고 HPLC를 사용하여 생성된 풀러렌 산화물을 분석한 결과 [$C_{70}(O)n$] (n=1) 임을 알 수 있었다.

• Elastomers and Composites
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• 제39권4호
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• pp.309-317
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• 2004

풀러렌[$C_{70}$]을 3-chloroperoxy benzoic acid, chromium (VI) oxide, benzoyl peroxide, trichloroisocyanuric acid 등의 산화제를 사용하여 마이크로파 조건에서 반응시켜 풀러렌 난화물[$C_{70}O_n$] ($n=1{\sim}3$ or n=1)을 합성하였다. 동일한 마이크로파 조건에서 여러가지 산화제와 풀러렌[$C_{70}$]의 고체상태 반응성은 3-chloroperoxy benzoic acid > chromium(VI) oxide > trichloroisocyanuric acid $\simeq$ benzoyl peroxide 순으로 증가함을 나타냈다. MALDI-TOF-MS, UV-visible, 그리고 HPLC를 사용하여 분석한 결과 생성된 풀러렌 산화물은 [$C_{70}O_n$] ($n=1{\sim}3$ or n=1)임을 알 수 있었다.

• Journal of Chest Surgery
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• 제49권1호
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• pp.9-14
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• 2016

Background: Tetralogy of Fallot (TOF) is a well-recognized congenital heart disease. Despite improvements in the outcomes of surgical repair, the optimal timing of surgery and type of surgical management of patients with TOF remains controversial. The purpose of this study was to assess outcomes following the repair of TOF in infants depending on the surgical procedure used. Methods: This study involved the retrospective review of 120 patients who underwent TOF repair between 2010 and 2013. Patients were divided into three groups depending on the surgical procedure that they underwent. Corrective surgery was done via the transventricular approach (n=40), the transatrial approach (n=40), or a combined atrioventricular approach (n=40). Demographic data and the outcomes of the surgical procedures were compared among the groups. Results: In the atrioventricular group, the incidence of the following complications was found to be significantly lower than in the other groups: complete heart block (p=0.034), right ventricular failure (p=0.027) and mediastinal bleeding (p=0.007). Patients in the atrioventricular group had a better postoperative right ventricular ejection fraction (p=0.001). No statistically significant differences were observed among the three surgical groups in the occurrence of tachycardia, renal failure, and tricuspid incompetence. The one-year survival rates in the three groups were 95%, 90%, and 97.5%, respectively (p=0.395). Conclusion: Combined atrioventricular repair of TOF in infancy can be safely performed, with acceptable surgical risk, a low incidence of reoperation, good ventricular function outcomes, and an excellent survival rate.

• Mass Spectrometry Letters
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• 제8권4호
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• pp.114-118
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• 2017

While saliva can be considered as good biological fluid for monitoring biomarkers due to many advantages including its communication with blood and the non-invasive nature during its sampling, its applications to that purpose is still limited. As a part of efforts to expand the applications of saliva to the protein biomarker research, we carried out global absolute quantitation of proteins in human whole saliva (WS) by bottom-up proteomics techniques mainly based on nLC-Q-IMS-TOF employing $MS^E$. From the analyses of a pooled WS sample collected from 22 healthy Korean volunteers, 93 proteins ranging from $5.89{\times}10^1ng/mL$ (immunoglobulin heavy chain) to $1.59{\times}10^4ng/mL$ (${\alpha}-amylase$ 1) were confirmed. For the validation of the present results, human serum albumin in the same sample was quantitated by ELISA and its result was compared with that from the nLC-Q-IMS-TOF study. As a result, there was no significant difference between two results from individual approaches ($1.18{\times}10^4{\pm}0.03{\times}10^4 ng/mL$ from nLC-Q-IMS-TOF experiments vs. $1.23{\times}10^4{\pm}0.07{\times}10^4ng/mL$ from ELISA experiments, n=3, p=0.309). To our knowledge, this is the first global absolute quantitation of proteins in human whole saliva and information from the present study can be widely used as the first level reference for the discovery of new protein biomarkers from human whole saliva as well as for quantitative applications of human whole saliva proteins.

• Journal of Microbiology and Biotechnology
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• 제29권4호
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• pp.548-557
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• 2019

Staphylococcus species have a ubiquitous habitat in a wide range of foods, thus the ability to identify staphylococci at the species level is critical in the food industry. In this study, we performed rapid identification of Staphylococcus species using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS was evaluated for the identification of Staphylococcus reference strains (n = 19) and isolates (n = 96) from various foods with consideration for the impact of sample preparation methods and incubation period. Additionally, the spectra of isolated Staphylococcus strains were analyzed using principal component analysis (PCA) and a main spectra profile (MSP)-based dendrogram. MALDI-TOF MS accurately identified Staphylococcus reference strains and isolated strains: the highest performance was by the EX method (83.3~89.5% accuracy) at species level identification (EDT, 70.3~78.9% accuracy; DT, less than 46.3~63.2% accuracy) of 24-h cultured colonies. Identification results at the genus level were 100% accurate at EDT, EX sample preparation and 24-h incubation time. On the other hand, the DT method showed relatively low identification accuracy in all extraction methods and incubation times. The analyzed spectra and MSP-based dendrogram showed that the isolated Staphylococcus strains were characterized at the species level. The performance analysis of MALDI-TOF MS shows the method has the potential ability to discriminate between Staphylococcus species from foods in Korea. This study provides valuable information that MALDI-TOF MS can be applied to monitor microbial populations and pathogenic bacteria in the food industry thereby contributing to food safety.

• Elastomers and Composites
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• 제40권1호
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• pp.45-52
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• 2005

풀러렌[$C_{60}$]은 3-chloroperoxy benzoic acid, benzoyl peroxide, trichloroisocyanuric acid, chromium(VI) oxide 등의 산화제를 사용하여 마이크로파 조건에서 반응시켜 풀러렌 산화물[$C_{60}(O)_n$] ($n=1{\sim}4$ or n=1)을 합성하였다. 동일한 마이크로파 조건에서 여러 가지 산화제와 풀러렌[$C_{60}$]의 고체상태 반응성은 3-chloroperoxy benzoic acid>benzoyl peroxide>trichloroisocyanuric acid$\simeq$chromium(VI) oxide 순으로 증가함을 나타냈다. MALDI-TOF-MS, UV-visible, 그리고 HPLC를 사용하여 분석한 결과 생성된 풀러렌 산화물은[$C_{60}(O)_n$] ($n=1{\sim}4$ or n=1)임을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1791-1800
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• 2004

Angiotensin I, a model decapeptide, was glycosylated and partially hydrolyzed with HCl (6 N, 80 $^{\circ}C$, 4 h), aminopeptidase, and carboxypeptidase Y. A single peptide mass map obtained from truncated peptides in the partial acid hydrolysate of angiotensin and its glycosylation product mixture by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry enabled sequencing of angiotensin by a combinatorial procedure. MALDI-TOF and electrospray ionization (ESI) tandem mass spectrometric results indicate that both the N-terminal amino group of aspartic acid and the guanidinium group of the second residue arginine are glycosylated.

• Elastomers and Composites
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• 제40권3호
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• pp.174-180
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• 2005

공기 중 초음파 조건에서 풀러렌$[C_{70}]$과 금속 헥사카르보닐 착물 $M(CO)_6$ (M=Cr, Mo, W)을 반응시켜 풀러렌 산화물 $[C_{70}O_n](n=1{\sim}2)$을 합성하였다. 동일한 초음파 조건에서 풀러렌$[C_{70}]$과 여러 가지 금속 헥사카르보닐 착물 $M(CO)_6$ (M=Cr, Mo, W)의 반응성은 $Mo(CO)_6$ > $W(CO)_6$ > $Cr(CO)_6$ 순으로 증가함을 나타냈다. MALDI-TOF-MS, UV-visible 스펙트럼과 HPLC를 사용하여 분석한 결과 초음파화학 반응의 생성물은 $[C_{70}O_n](n=1{\sim}2)$ 임을 알 수 있었다.