• Journal of Ginseng Research
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• 제43권2호
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• pp.305-311
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• 2019

Background: Gintonin is a ginseng-derived exogenous ligand of the G protein-coupled lysophosphatidic acid (LPA) receptor. We previously reported that gintonin stimulates gliotransmitter release in primary cortical astrocytes. Astrocytes play key roles in the functions of neurovascular systems. Although vascular endothelial growth factor (VEGF) is known to influence the normal growth and maintenance of cranial blood vessels and the nervous system, there is little information about the effect of gintonin on VEGF regulation in primary astrocytes, under normal and hypoxic conditions. Methods: Using primary cortical astrocytes of mice, the effects of gintonin on the release, expression, and distribution of VEGF were examined. We further investigated whether the gintonin-mediated VEGF release protects astrocytes from hypoxia. Results: Gintonin administration stimulated the release and expression of VEGF from astrocytes in a concentration- and time-dependent manner. The gintonin-mediated increase in the release of VEGF was inhibited by the LPA1/3 receptor antagonist, Ki16425; phospholipase C inhibitor, U73122; inositol 1,4,5- triphosphate receptor antagonist, 2-APB; and intracellular $Ca^{2+}$ chelator, BAPTA. Hypoxia further stimulated astrocytic VEGF release. Gintonin treatment stimulated additional VEGF release and restored cell viability that had decreased due to hypoxia, via the VEGF receptor pathway. Altogether, the regulation of VEGF release and expression and astrocytic protection mediated by gintonin under hypoxia are achieved via the LPA receptor-VEGF signaling pathways. Conclusion: The present study shows that the gintonin-mediated regulation of VEGF in cortical astrocytes might be neuroprotective against hypoxic insults and could explain the molecular basis of the beneficial effects of ginseng on the central nervous system.

• 대한의용생체공학회:의공학회지
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• 제28권3호
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• pp.429-440
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• 2007

A coded excitation has been studied to improve the performance for ultrasound imaging in term of SNR, imaging frame rate, contrast to tissue ratio, and so forth. However, it requires a complicated arbitrary waveform transmitter for each active channel that is typically composed of a multi-bit Digital-to-Analog Converter (DAC) and a linear power amplifier (LPA). Not only does the LPA increase the cost and size of a transmitter block, but it consumes much power, increasing the system complexity further and causing a heating-up problem. This paper proposes an optimized 1.5bit fourth order sigma-delta modulation technique applicable to design an efficient arbitrary waveform generator with greatly reduced power dissipation and hardware. The proposed SDM can provide a required SQNR with a low over-sampling ratio of 4. To this end, the loop coefficients are optimized to minimize the quantization noise power in signal band while maintaining system stability. In addition, the decision level for the 1.5 bit quantizer is optimized for a given input waveform, which results in the SQNR improvement of more than 5dB. Computer simulation results show that the SQNR of a FM(frequency modulated) signal generated by using the proposed method is about 26dB, and the peak side-lobe level (PSL) of its compressed waveform on receive is -48dB.

• Journal of Chest Surgery
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• 제22권2호
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• pp.256-264
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• 1989

Modified Blalock-Taussig operation remains the standard technique of systemic-to-pulmonary artery shunt in patients of congenital heart disease with decreased pulmonary blood flow. We reviewed the 41 patients who had been performed modified Blalock-Taussig operation from March 1985 to Feb. 1988, and angiographically measured pulmonary artery size before and after shunt, and calculated pulmonary artery index [PAI] and ratio of left and right pulmonary artery to descending aorta[[LPA+RPA]/dAo]. The mean duration of palliation after shunt operation was 624 days and mean age of the patient at shunt operation was 3.59 years. Mean PAI increased significantly from 131.15*67.11 mm2/M2 preoperatively to 232.70*84.46 mm2/M2 postoperatively. Mean ratio of right and left pulmonary artery to descending aorta also increased significantly from 1.48*0.40 preoperatively to 1.92*0.50 postoperatively. All patients manifested clinical improvement; there was mean decrease in hematocrit of 8.95%, mean increase in arterial oxygen saturation of 11.08%. Pulmonary arterial growth was not influenced by age at operation, initial pulmonary artery size, or graft size, but significantly influenced by antegrade flow. The patients who have some antegrade flow were in more increase of PAI. There were no linear correlation between change of PAI, change of [[LPA+RPA]/dAo], SaO2, and duration. But, according to Scatterplot between change of PAI and duration, some complex correlation was suggested and mean PAI was decreased after 2-year palliation. We concluded that modified Blalock-Taussig operation is excellent palliative surgery for pulmonary artery growth especially on the patient who have some antegrade flow, and the proper duration of palliation was about 2 years.

• Journal of the Korean Data Analysis Society
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• 제20권6호
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• pp.3049-3067
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• 2018

최근 조직몰입(organizational commitment) 3요인(정서적 몰입, 규범적 몰입, 지속적 몰입) 모델(Allen, Meyer, 1990, 1991) 관련 연구에서 사람중심 접근법(person-centered approach)이 많은 관심을 받고 있지만 아직 국내 연구자들에게는 크게 확산되지 못하고 있다. 이에 본 논문은 사람중심 접근법의 개념과 관련 자료분석 방법을 군집분석(cluster analysis)과 잠재프로파일분석(latent profile analysis)을 중심으로 소개하고자 한다. 또한 이러한 방법들의 실제 적용 사례를 제시하기 위해 국내 직장인들 349명으로부터 수집한 자료를 바탕으로 군집분석과 잠재프로파일분석을 각각 실행하여 각 분석으로부터 6개의 조직몰입 프로파일 유형들을 도출하였으며 그 결과를 비교하였다. 뿐만 아니라, 조직몰입 프로파일 유형 간 이직의도(turnover intention)의 차이를 살펴봄으로써 도출된 프로파일의 타당성을 확인하였다. 본 논문은 조직몰입에 대한 기존의 변수중심 접근법(variable-centered approach)에 대한 보완적 방법으로 사람중심 접근법이 갖는 의미를 이해하고, 나아가 국내 직장인들의 조직몰입 프로파일 유형을 살펴볼 수 있다는 점에서 국내 연구자들 뿐만 아니라 실무담당자들에게 시사하는 바가 크다고 할 수 있다.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.73-86
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• 2003

Endothelins secreted from keratinocytes are intrinsic madiators for human melanocytes in UVB-induced pigmentation. Antimelanogenic ingredient, 1,2-Ο-diferulylglycerol(SM709) isolated from bamboo extract inhibited the melanin synthesis of Bl6F10 melanoma cells by 62%. To understand the cellular mechanism of antimelanogenic activity of SM709 in human melanocytes, the effects of SM709 on the ET-l-induced $Ca^{2+}$ mobilization were investigated. ET-l receptors in human melanocytes were characterized by using specific antagonist and found that ET-l increased intracellular $Ca^{2+}$ by activating ET-B receptor. SM709 completely blocked the ET-l-induced intracellular $Ca^{2+}$ increase and its inhibitory effect showed dose- and time- dependent manners. To investigate the role of SM709 on intracellular $Ca^{2+}$ store, when the $Ca^{2+}$ store was partially depleted by thapsigargin; a specific inhibitor of ER-type $Ca^{2+}$-ATPase, caffeine-induced $Ca^{2+}$ mobilization did not changed in the presence or absence of SM709, suggesting that SM709 has no effect on the $Ca^{2+}$ store. It is known that LPA receptor and P$_2$ receptor are linked to InsP$_3$ second messenger system. When these receptors in melanocytes were activated by LPA and ATP, the intracellular $Ca^{2+}$ signaling was observed even in the presence of SM709. From the above results, it can be suggested that SM709 has an antimelanogenic activity by antagonizing the ET-B receptor, resulting in subsequent intracellular $Ca^{2+}$ signaling, in UV induced pigmentation.nduced pigmentation.

• 대한임상검사과학회지
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• 제47권4호
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• pp.175-181
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• 2015

알러지성 접촉피부염 유발제인 수은의 독성에 대한 청미래덩굴(Smilax china L.) 추출물의 영향을 조사하기 위하여 배양 NIH3T3 섬유모세포에 여러 농도의 메틸수은(methylmercuric chloride, MMC)을 72시간 동안 처리한 후 이들의 세포독성을 조사하였다. 또한, MMC의 독성에 대한 청미래덩굴 추출물의 보호효과를 항산화 측면에서 조사하여 다음과 같은 결론을 얻었다. MMC는 농도 의존적으로 배양 NIH3T3 섬유모세포의 세포생존율을 유의하게 감소하였으며 $XTT_{50}$값이 100 uM 이하로서 고독성(highly-toxic)인 것으로 나타났다. 또한, MMC의 독성이 항산화제인 vit. E에 의하여 방어됨으로서 MMC의 독성에 산화적 손상이 관여하고 있는 것으로 나타났다. 한편, MMC의 세포독성에 대한 청미래덩굴 추출물의 방어효과에 있어서 청미래덩굴 추출물은 MMC에 의하여 감소된 세포생존율을 유의하게 증가시킴으로서 MMC의 독성을 방어하였다. 또한, 청미래덩굴 추출물은 전자공여능(EDA)을 비롯한 SOD-유사 활성(SLA) 및 지질과산화능(LPA)와 같은 항산화 효과를 나타냈다. 이상의 결과로부터 청미래덩굴과 같은 천연 성분은 산화적 손상과 관련된 염증성 피부질환의 치료를 위한 항산화제로서의 미래 가능한 천연소재라고 생각된다.

• 한국심리학회지 : 문화 및 사회문제
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• 제27권2호
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• pp.167-189
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• 2021

본 연구는 그릿(노력과 흥미)과 열정 마인드셋(고정 vs. 성장)에 따라 잠재집단이 존재하는지 확인하고, 각 집단에 따라 우울, 불안, 행복과 같은 심리적 특성과 진로 준비를 위한 적응성에 유의미한 차이가 있는지 살펴보고자 하였다. 이를 위해 만 18세에서 만 25세까지의 대학생 328명을 대상으로 잠재프로파일분석(LPA)을 시행한 결과, 총 4개의 프로파일 그룹을 도출하였다. 도출된 잠재 집단으로, 그릿과 열정성장 마인드셋이 모두 높은 '성장적 성취형(LP1, 22.2%)', 모든 기준에서 평균 수준인 '평균형(LP2, 63.8%),' 그릿이 낮고 열정고정 마인드셋이 높은 '고정적 제한형(LP3, 8.8%),' 그리고 그릿은 낮았으나 열정성장 마인드셋은 높았던 '성장적 표류형(LP4, 5.1%)'이 있었다. 집단별 심리적 특성 및 진로적응성에서의 차이를 살펴본 결과, '성장적 성취형' 집단이 가장 적응적인 수준을 보였고, '고정적 제한형' 집단이 이와 가장 큰 대조를 이루었다. 본 연구는 개인의 심리적 특성에는 그릿이, 진로적응성에서는 열정 성장 마인드셋이 보다 적응적인 영향을 끼칠 수 있음을 시사한다. 따라서 개인의 종합적 심리적 안녕감을 높이고 진로 준비를 위한 적응 수준을 높이기 위한 개입으로 열정 마인드셋과 그릿을 함께 고려할 필요가 있음을 제안한다.

• Journal of Ginseng Research
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• 제47권3호
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• pp.366-375
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• 2023

Background: Ginseng contains three active components: ginsenosides, gintonin, and polysaccharides. After the separation of 1 of the 3 ingredient fractions, other fractions are usually discarded as waste. In this study, we developed a simple and effective method, called the ginpolin protocol, to separate gintonin-enriched fraction (GEF), ginseng polysaccharide fraction (GPF), and crude ginseng saponin fraction (cGSF). Methods: Dried ginseng (1 kg) was extracted using 70% ethanol (EtOH). The extract was water fractionated to obtain a water-insoluble precipitate (GEF). The upper layer after GEF separation was precipitated with 80% EtOH for GPF preparation, and the remaining upper layer was vacuum dried to obtain cGSF. Results: The yields of GEF, GPF, and cGSF were 14.8, 54.2, and 185.3 g, respectively, from 333 g EtOH extract. We quantified the active ingredients of 3 fractions: L-arginine, galacturonic acid, ginsenosides, glucuronic acid, lysophosphatidic acid (LPA), phosphatidic acid (PA), and polyphenols. The order of the LPA, PA, and polyphenol content was GEF > cGSF > GPF. The order of L-arginine and galacturonic acid was GPF >> GEF = cGSF. Interestingly, GEF contained a high amount of ginsenoside Rb1, whereas cGSF contained more ginsenoside Rg1. GEF and cGSF, but not GPF, induced intracellular [Ca²⁺]_i transient with antiplatelet activity. The order of antioxidant activity was GPF > GEF = cGSF. Immunological activities (related to nitric oxide production, phagocytosis, and IL-6 and TNF-α release) were, in order, GPF > GEF = cGSF. The neuroprotective ability (against reactive oxygen species) order was GEF > cGSP > GPF. Conclusion: We developed a novel ginpolin protocol to isolate 3 fractions in batches and determined that each fraction has distinct biological effects.

• Journal of Chest Surgery
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• 제17권1호
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• pp.32-40
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• 1984

During the past six years from July 1977 to June 1983, fifteen adult patients of patent ductus arteriosus were surgically treated. The results were as follows: 1. Of the 15 patients, their age range was 17 to 34 years with a mean of 24 years, and sexual predominance was women [9. cf. 6 men]. 2. The most common symptom showed exertional dyspnea, and 10 patients were classed in NYHA class II, the rest were all class III. 3. On physical examination, all patients were auscultated continuous murmur, but concomitantly diastolic murmur was noted apical region in 2 patients. 4. On roentgenogram of chest, normal finding was 3 patients, and the other patients were revealed the evidence of pulmonary congestion. 5. The electrocardiogram was normal in 6 patients, but LVH was seen in 5, and 2 patients were LVH+ LAH. 6. Cardiac catheterization was performed in 12, and mean value of SO2[LPA-RV] was 6.3%, Q/Q 2.09, peak systolic pulmonary arterial pressure 45.3 mmHg, and Rp/Rs 0.365. 7. All operations were carried out by posterolateral thoracotomy. In 6 patients, division and suture of ductus were possible, the other patients were treated by division and ligation with heavy silk or Dacron patch. 8. Postoperative complications were hoarseness, persistent murmur, reoperation for bleeding, and atelectasis. Early and late mortality was 20% [3 patients], and cause of death was mainly aneurysmal rupture of previous operative site.

• 한국노년학
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• 제36권3호
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• pp.765-783
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• 2016

본 연구는 한국노인의 사회적 연계망 자체를 좀 더 심도있게 이해하기 위하여 2014년도 노인실태조사자료(65세 이상 10,279명)를 활용하여 관계망 크기, 연계와의 접촉 빈도, 연계에 대한 친밀도를 중심으로 잠재프로파일분석(LPA)을 실시하였다. 그 결과 노인의 사회적 연계망은 고립형(11.6%), 가족의례형(17.7%), 가족친밀형(23.6%), 제한적 다층친밀형(28.4%), 다층형(18.8%)의 다섯 개 유형으로 도출되었다. 또한 도출된 잠재집단 유형별 특징을 비교하였고, 사회적 관계망 유형에 영향을 미치는 요인을 분석하기 위한 다항로지스틱회귀분석을 실시하였다. 분석결과, 고립형 노인의 3/4은 여성이며 독거가구 비율이 약 절반을 차지하는 것으로 나타났다. 또한 상대적으로 평균연령이 높고, 도시지역에 거주하는 노인, 신체적 제한이 있는 노인, 사회적 지위가 낮은 직종에 종사한 노인이 고립형에 속할 가능성이 높은 것으로 나타났다. 반면 다층형의 경우 여성보다는 남성노인이, 연령이 낮을수록, 학력이 높을수록, 전문 관리 사무직에 종사한 노인일수록 다층형에 속할 가능성이 높았다. 한편 가족의례형과 가족친밀형은 배우자 혹은 자녀를 중심으로 연계망이 형성되어 있고, 노인부부가구의 비중이 높다는 공통점을 가지고 있으나, 가족의례형은 상대적으로 여성 비중이 높다는 특징이 있다. 그리고 제한적 다층친밀형은 배우자보다는 자녀와 친구 이웃과의 연계망의 크기, 빈도, 친밀도가 다층형 다음으로 높은 집단으로 여성노인 및 저학력이면서 농림어업에 종사한 비중이 높게 나타났다. 이러한 연구결과에 기초하여 노년기의 사회적 연계망 유형의 다양성이 갖는 학술적 및 정책적 함의와 향후 연구방향을 논의하였다.