• Investigative Magnetic Resonance Imaging
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• 제1권1호
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• pp.135-141
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• 1997

목적: 초음파에서 의심된 국소적 간지방병변을 진단함에 있어 화학적 포화 방식의 지방억제를 호함한 호흡정지 급속 자기공명영상의 유용성을 알아보기 위함이다. 대상 및 방법: 초음파검사에서 발견된 국소 간병변의 진단을 위해 자기공명영상을 촬영할 때 별도의 parameter 조정없이 지방억제 전후의 영상을 얻을 수 있는 화학적 포화방식의 영상을 추가하였을 때 국소병변의 전체에 걸쳐 균일한 신호가도의 변화가 있었던 환자 13명을 대상으로 하였다. 지방억제 전후의 영상을 fast low-angle shot(FLASH) sequence를 이용한 T1강조영상과 turbo spin-echo sequence를 이용한 T2강조영상으로 호흡정지증의 급속영상을 얻었으며 각각의 병변에 대해 지방억제 전후 의 T1강조영상과 T2강조영상에서 주변 간실질에 대해 상대적인 신호강도의 증감과 초음파 소견상의 에코의 증감을 비교하였다. 결과: T1이나 T2강조영상에서 신호강도가 지방억제 후 감소했던 환자는 7명이었으며 이 중 3명은 지방억제 후의 T1강조영상에서만 신호강도가 감소하였으며 7명 모두 초음파상 고에코의 국소병변과 일치하여 국소지방침착 소견과 일치하였다. 지방억제 후 T2강조영상에서만 주변 간실질에 비해 신호강도가 높았던 2명을 포함하여 지방억제 후 T1과 T2강조영상에서 신호강도가 상대적으로 높아 보였던 6명은 모두 초음파에서 저에코의 병변을 가지고 있어서 국소지방결여와 잘 일치하였다. 국소지방침착의 경우 지방억제 후 T1강조영상의 신호강도의 감소가 T2강조영상에서의 변화에 비해 컸으며(P=0.0002) 국소지방결여의 경우는 T2강조영상에서의 변화가 T1강조영상에 비해 상대적으로 현저하였다(P=0.042). 결론: 호흡정지 급속영상방법의 T1과 T2강조영상에서 공히 화학적 포화방식을 이용한 지방억제 전후의 영상을 얻으면 초음파에서 발견된 국소병변을 간지방변화로 특성화하기에 충분할 것이다.

• Journal of Nutrition and Health
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• 제52권6호
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• pp.529-539
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• 2019

본 연구에서는 달맞이순의 항산화 및 항비만효과를 확인하기 위하여 건달맞이순 50% 에탄올 추출물 (OLE)을 이용하여 4가지 방법으로 in vitro 항산화효과를 측정하였고, C57BL/6 마우스에게 고지방식이 (45%Kcal fat)를 14주 동안 섭취시켜 비만을 유도하면서 OLE를 경구 투여하여 항비만효과와 in vivo 항산화효과를 알아보았다. OLE의 DPPH 라디칼 소거능과 SOD 유사 활성을 측정한 결과 IC₅₀은 각각 26.2 ㎍/mL과 327.6 ㎍/mL이었으며, FRAP 측정 결과 100 ㎍/mL 농도에서 56.7 ㎍ AA eq./mL의 효능을 보였다. 또한, hUC-MSC 세포에 OLE (200 ㎍/mL)를 처리 한 결과 노화로 인하여 감소된 GSH 수준을 65.1% 증가시켰다. 한편, 마우스에게 고지방식이와 함께 OLE를 저수준 (50 mg/kg BW; OL50)과 고수준 (100 mg/kg BW; OL100)으로 경구 투여한 결과 체중증가량은 대조군에 비하여 각각 41.5%와 42.2% 감소하였고, 내장지방량은 각각 40.5%와 45.9% 감소하였으며, 부고환지방세포의 크기는 각각 33.1%와 35.3% 감소하여 매우 우수한 비만억제효과를 보였다 (p < 0.05). OLE의 경구 투여는 고지방식이 대조군에 비하여 혈중 렙틴 농도와 중성지방 농도를 유의하게 감소시켰고, 특히 OL100군에서는 동맥경화지수 및 혈중 MDA 농도도 유의하게 감소하였다 (p < 0.05). 마우스 지방조직에서 측정한 catalase와 SOD-1의 활성은 고지방식이섭취로 인하여 증가하였으나 OLE 경구 투여 시 유의하게 감소하였다 (p < 0.05). 또한, 부고환 지방에서 지방대사 관련 인자들의 mRNA 발현량을 RT-PCR로 측정한 결과 OLE의 경구 투여는 고지방식이 섭취로 인하여 증가하였던 렙틴, PPARγ와 FAS의 발현을 유의하게 감소시킨 반면 고지방식이 섭취로 감소되었던 아디포넥틴의 발현량은 유의하게 증가시켰다 (p < 0.05). 고지방식이로 인하여 증가하였던 CPT-1의 발현량은 OLE 투여시 감소되는 경향을 보였으며, SREBP-1c의 발현량은 실험군 간에 유의한 차이가 없었다. 이들 연구결과를 종합하면, in vitro 항산화효과가 우수한 OLE를 고지방식이로 유도된 비만 마우스에게 경구 투여하였을 때 체내 산화적 스트레스를 낮추고, 지방합성을 억제함으로써 체중과 내장 지방량의 증가를 억제시키는 항비만 효과를 나타내었다. 따라서, OLE는 항산화기능식품 또는 비만 및 비만관련 만성질환을 예방하는 기능성식품의 개발에 기능성 천연소재로 활용될 수 있으리라 기대된다.

• Investigative Magnetic Resonance Imaging
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• 제18권2호
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• pp.87-106
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• 2014

Purpose : To describe how a robust implementation of a radial 3D gradient-echo sequence with stack-of-stars sampling can be achieved, to review the imaging properties of radial acquisitions, and to share the experience from more than 5000 clinical patient scans. Materials and Methods: A radial stack-of-stars sequence was implemented and installed on 9 clinical MR systems operating at 1.5 and 3 Tesla. Protocols were designed for various applications in which motion artifacts frequently pose a problem with conventional Cartesian techniques. Radial scans were added to routine examinations without selection of specific patient cohorts. Results: Radial acquisitions show significantly lower sensitivity to motion and allow examinations during free breathing. Elimination of breath-holding reduces failure rates for non-compliant patients and enables imaging at higher resolution. Residual artifacts appear as streaks, which are easy to identify and rarely obscure diagnostic information. The improved robustness comes at the expense of longer scan durations, the requirement for fat suppression, and the nonexistence of a time-to-center value. Care needs to be taken during the configuration of receive coils. Conclusion: Routine clinical use of radial stack-of-stars sequences is feasible with current MR systems and may serve as substitute for conventional fat-suppressed T1-weighted protocols in applications where motion is likely to degrade the image quality.

• 동의생리병리학회지
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• 제32권1호
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• pp.43-50
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• 2018

Korean Red Ginseng (RG) are used as a traditional treatment for improve blood circulation. This experimental study was designed to investigate the inhibitory effects of Korean red ginseng on lipid metabolism in high fat/cholesterol diet (HFCD)-induced hypertriglyceridemia. Sprague Dawley rats were fed the HFCD diet with/without fluvastatin (Flu, positive control) 3 mg/kg/day, and RG 125 or 250 mg/kg/day, respectively. All groups received regular diet or HFCD diet, respectively, for 13 weeks. The last three groups treatment of Flu and RG 125, and RG 250 orally for a period of 9 weeks. Group 1, reular diet; group 2, HFCD diet; group 3, Flu + HFCD diet; group 4, RG 125 + HFCD diet; group 5, RG 250 + HFCD diet. As a result, treatment with low or high doses of RG markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL) in HFCD-fed rats. RG and Flu also led to an increase in lipoprotein lipase activity in the HFCD group. On the other hand, RG and Flu led to an decrease in fatty acid synthase and free fatty acid activity in the HFCD group. Treatment with RG suppressed increased expressions of $PPAR-{\alpha}$ and AMPK in HFCD rat liver or muscle. In addition, the RG attenuated triglyceridemia by inhibition of $PPAR-{\gamma}$ and FABP protein expression levels and LXR and SREBP-1 gene expression in liver or muscle. The RG significantly prevented the development of the metabolic disturbances such as hypertriglyceridemia and hyperlipidemia. Taken together, the administration of RG improves hypertriglyceridemia through the alteration in suppression of triglyceride synthesis and accentuated of triglyceride decomposition. These results suggested that RG is useful in the prevention or treatment of hypertriglyceridemia.

• 대한환경공학회지
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• 제37권1호
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• pp.52-59
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• 2015

최근 낙농업은 지구온난화 등 환경에 미치는 영향 문제에 직면하고 있다. 특히 젖소로부터 발생하는 장내발효 메탄가스와 젖소를 사육하는데 필요한 사료작물의 재배에 의한 여러 환경영향이 이슈가 되고 있다. 유럽에서는 Product Environmental Footprint (PEF)라는 통합적 라벨링제도를 통해 공산품뿐만 아니라 낙농제품 등과 같은 각종 농업생산물에 대한 환경영향 산정 방법론을 연구하고 있는 실정이다. 이 연구에서는 전과정평가(Life cycle assessment, LCA)를 이용하여 국내 낙농우(젖소)의 전과정에 대해 전과정 단계별로 환경영향을 산정하고 주요이슈를 규명하였다. 시스템 경계는 젖소를 위한 사료작물 재배, 사료가공, 전소 관리와 가축분뇨처리(cradle-to-gate)이다. 기능단위는 1 kg의 우유(Fat Protein Corrected Milk, FPCM(유지 및 단백질 보정유)) 생산이다. 국내 낙농우(젖소) 시스템의 환경영향은 사육단계, 사료작물 재배단계가 분뇨처리단계 및 사료생산 단계보다 더 많은 환경영향범주에서 주요 전과정 단계로 규명되었다. 이에 농장 내 우유 생산과정 환경영향을 저감하기 위해서는 사육 시 장내발효 메탄가스 발생 억제기술 개발, 농장 기기 장비의 에너지효율 개선, 작물 재배 시 발생하는 침출수 관리 및 사료작물 재배 시 비료의 유실방지 기술 개발 등이 주요 환경이슈를 개선하기 위한 방안으로 판단된다.

• 운동영양학회지
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• 제16권2호
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• pp.65-71
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• 2012

Oxygen is the final acceptor of electron transport from fat and carbohydrate oxidation, which is the rate-limiting factor for cellular ATP production. Under altitude hypoxia condition, energy reliance on anaerobic glycolysis increases to compensate for the shortfall caused by reduced fatty acid oxidation [1]. Therefore, training at altitude is expected to strongly influence the human metabolic system, and has the potential to be designed as a non-pharmacological or recreational intervention regimen for correcting diabetes or related metabolic problems. However, most people cannot accommodate high altitude exposure above 4500 M due to acute mountain sickness (AMS) and insulin resistance corresponding to a increased levels of the stress hormones cortisol and catecholamine [2]. Thus, less stringent conditions were evaluated to determine whether glucose tolerance and insulin sensitivity could be improved by moderate altitude exposure (below 4000 M). In 2003, we and another group in Austria reported that short-term moderate altitude exposure plus endurance-related physical activity significantly improves glucose tolerance (not fasting glucose) in humans [3,4], which is associated with the improvement in the whole-body insulin sensitivity [5]. With daily hiking at an altitude of approximately 4000 M, glucose tolerance can still be improved but fasting glucose was slightly elevated. Individuals vary widely in their response to altitude challenge. In particular, the improvement in glucose tolerance and insulin sensitivity by prolonged altitude hiking activity is not apparent in those individuals with low baseline DHEA-S concentration [6]. In addition, hematopoietic adaptation against altitude hypoxia can also be impaired in individuals with low DHEA-S. In short-lived mammals like rodents, the DHEA-S level is barely detectable since their adrenal cortex does not appear to produce this steroid [7]. In this model, exercise training recovery under prolonged hypoxia exposure (14-15% oxygen, 8 h per day for 6 weeks) can still improve insulin sensitivity, secondary to an effective suppression of adiposity [8]. Genetically obese rats exhibit hyperinsulinemia (sign of insulin resistance) with up-regulated baseline levels of AMP-activated protein kinase and AS160 phosphorylation in skeletal muscle compared to lean rats. After prolonged hypoxia training, this abnormality can be reversed concomitant with an approximately 50% increase in GLUT4 protein expression. Additionally, prolonged moderate hypoxia training results in decreased diffusion distance of muscle fiber (reduced cross-sectional area) without affecting muscle weight. In humans, moderate hypoxia increases postprandial blood distribution towards skeletal muscle during a training recovery. This physiological response plays a role in the redistribution of fuel storage among important energy storage sites and may explain its potent effect on changing body composition. Conclusion: Prolonged moderate altitude hypoxia (rangingfrom 1700 to 2400 M), but not acute high attitude hypoxia (above 4000 M), can effectively improve insulin sensitivity and glucose tolerance for humans and antagonizes the obese phenotype in animals with a genetic defect. In humans, the magnitude of the improvementvaries widely and correlates with baseline plasma DHEA-S levels. Compared to training at sea-level, training at altitude effectively decreases fat mass in parallel with increased muscle mass. This change may be associated with increased perfusion of insulin and fuel towards skeletal muscle that favors muscle competing postprandial fuel in circulation against adipose tissues.

• IMMUNE NETWORK
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• 제13권4호
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• pp.123-132
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• 2013

Obesity is consistently increasing in prevalence and can trigger insulin resistance and type 2 diabetes. Many lines of evidence have shown that macrophages play a major role in inflammation associated with obesity. This study was conducted to determine metformin, a widely prescribed drug for type 2 diabetes, would regulate inflammation through down-regulation of scavenger receptors in macrophages from obesity-induced type 2 diabetes. RAW 264.7 cells and peritoneal macrophages were stimulated with LPS to induce inflammation, and C57BL/6N mice were fed a high-fat diet to generate obesity-induced type 2 diabetes mice. Metformin reduced the production of NO, $PGE_2$ and pro-inflammatory cytokines ($IL-1{\beta}$, IL-6 and $TNF-{\alpha}$) through down-regulation of $NF-{\kappa}B$ translocation in macrophages in a dose-dependent manner. On the other hand, the protein expressions of anti-inflammatory cytokines, IL-4 and IL-10, were enhanced or maintained by metformin. Also, metformin suppressed secretion of $TNF-{\alpha}$ and reduced the protein and mRNA expression of $TNF-{\alpha}$ in obese mice as well as in macrophages. The expression of scavenger receptors, CD36 and SR-A, were attenuated by metformin in macrophages and obese mice. These results suggest that metformin may attenuate inflammatory responses by suppressing the production of $TNF-{\alpha}$ and the expressions of scavenger receptors.

• BMB Reports
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• 제49권8호
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• pp.401-402
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• 2016

S6K1 is a key regulator of cell growth, cell size, and metabolism. Although the role of cytosolic S6K1 in cellular processes is well established, the function of S6K1 in the nucleus remains poorly understood. Our recent study has revealed that S6K1 is translocated into the nucleus upon adipogenic stimulus where it directly binds to and phosphorylates H2B at serine 36. Such phosphorylation promotes EZH2 recruitment and subsequent histone H3K27 trimethylation on the promoter of its target genes including Wnt6, Wnt10a, and Wnt10b, leading to repression of their expression. S6K1-mediated suppression of Wnt genes facilitates adipogenic differentiation through the expression of adipogenic transcription factors PPARγ and Cebpa. White adipose tissues from S6K1-deficient mice consistently exhibit marked reduction in H2BS36 phosphorylation (H2BS36p) and H3K27 trimethylation (H3K27me3), leading to enhanced expression of Wnt genes. In addition, expression levels of H2BS36p and H3K27me3 are highly elevated in white adipose tissues from mice fed on high-fat diet or from obese humans. These findings describe a novel role of S6K1 as a transcriptional regulator controlling an epigenetic network initiated by phosphorylation of H2B and trimethylation of H3, thus shutting off Wnt gene expression in early adipogenesis.

• Preventive Nutrition and Food Science
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• 제19권3호
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• pp.178-186
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• 2014

Many recent studies have focused on maintaining a healthy life by preventing and/or postponing the aging process. Numerous studies have reported that continuous exposure to reactive oxygen species can stimulate skin aging and that excessive accumulation of fat can cause an impaired skin barrier and tissue structure alterations. Thus, the maintenance of antioxidant homeostasis and the suppression of adipose accumulation are important strategies for skin anti-aging. Here, we prepared three types of extracts [whole juice, acetone-perchloric acid (PCA), and ethanol] from 20 fruits and medicinal herbs native to the Gyeongnam area of Korea. The total phenolic content of each extract was analyzed, and we observed higher total phenolic contents in the medicinal herbs. Consistent with this, the results of the oxygen radical absorbance activity capacity assay indicated that the in vitro antioxidant activities of the medicinal herb extracts were stronger than those of the fruit extracts. The fruits and medicinal herbs had strong effects on cell-based systems, including $H_2O_2$-induced oxidative stress in human keratinocytes and 3T3-L1 lipid accumulation. Nishimura Wase persimmon, Taishu persimmon, wrinkled giant hyssop, sweet wormwood, Chinese cedar, red perilla, tan shen, hiyodori-jogo, and cramp bark may be natural anti-aging materials with effective antioxidant and anti-adipogenic activities. Taken together, our findings may provide scientific evidence supporting the development of functional foods and nutraceuticals from fruits and medicinal herbs.

• Journal of Korean Neurosurgical Society
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• 제30권9호
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• pp.1120-1126
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• 2001

Objective : The development of magnetic resonance neurography(MRN) has made it possible to produce highresolution images of peripheral nerves themselves, as well as associated intraneural and extraneural lesions. We evaluated the clinical application and utility of high-resolution MRN techniques for the diagnosis and treatment of a variety of peripheral nerve disorder(PND)s. Material and Method : MRN images were obtained using T1-weighted spin echo, T2-weighted fast spin echo with fat suppression, and short tau inversion recovery(STIR) fast spin-echo pulse sequences. Fifteen patients were studied, three with brachial plexus tumors, five with chronic entrapment syndromes, and seven with traumatic peripheral lesions. Ten patients underwent surgery. Results : In MRN with STIR sequences of axial and coronal imagings, signals of the peripheral nerves with various lesions were detected as fairly bright signals and were discerned from signals of the uninvolved nerves. Increased signal with proximal swelling and distal flattening of the median nerve were seen in all patients of carpal tunnel syndrome. Among the eight patients with brachial plexus injury or tumors, T2-weighted MRN showed increased signal intensity in involved roots in five, enhanced mass lesions in three, and traumatic pseudomeningocele in three. Other associated MRI findings were adjacent bony signal change, neuroma, root adhesion and denervated muscle atophy with signal change. Conclusion : MRN with high-resolution imaging can be useful in the preoperative evaluation and surgical planning in patients with peripheral nerve lesions.