• BMB Reports
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• 제45권12호
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• pp.700-706
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• 2012

Obesity is a worldwide epidemic as well as being a major risk factor for diabetes, cardiovascular diseases and several types of cancers. Obesity is mainly due to the overgrowth of adipose tissue arising from an imbalance between energy intake and energy expenditure. Adipose tissue, primarily composed of adipocytes, plays a key role in maintaining whole body energy homeostasis. In view of the treatment of obesity and obesity-related diseases, it is critical to understand the detailed signal transduction mechanisms of adipogenic differentiation. Adipogenic differentiation is tightly regulated by many key signal cascades, including insulin signaling. These signal cascades generally transfer or amplify the signal by using serial tyrosine phosphorylations. Thus, protein tyrosine kinases and protein tyrosine phosphatases are closely related to adipogenic differentiation. Compared to protein tyrosine kinases, protein tyrosine phosphatases have received little attention in adipogenic differentiation. This review aims to highlight the involvement of protein tyrosine phosphatases in adipogenic differentiation and the possibility of protein tyrosine phosphatases as drugs to target obesity.

• Natural Product Sciences
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• 제19권1호
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• pp.1-7
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• 2013

AMP-activated protein kinase (AMPK) is a major cellular energy sensor and master regulator of metabolic homeostasis. On activation, this cellular fuel sensing enzyme induces a series of metabolic changes to balance energy consumption via multiple downstream signaling pathways controlling nutrient uptake and energy metabolism. This pivotal role of AMPK has led to the development of numerous AMPK activators which might be used as novel drug candidates in the treatment of AMPK related disorders, diabetes, obesity, and other metabolic diseases. Consequently, a number of patents have been published on AMPK activators from natural products and other sources. This review covers the patented AMPK activators from natural products and their therapeutic potential in treatment or prevention of metabolic diseases including diabetes and obesity.

• Molecules and Cells
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• 제28권3호
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• pp.139-148
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• 2009

Cell death has been traditionally classified in apoptosis and necrosis. Apoptosis, known as programmed cell death, is an active form of cell death mechanism that is tightly regulated by multiple cellular signaling pathways and requires ATP for its appropriate process. Apoptotic death plays essential roles for successful development and maintenance of normal cellular homeostasis in mammalian. In contrast to apoptosis, necrosis is classically considered as a passive cell death process that occurs rather by accident in disastrous conditions, is not required for energy and eventually induces inflammation. Regardless of different characteristics between apoptosis and necrosis, it has been well defined that both are responsible for a wide range of human diseases. Glycogen storage disease type I (GSD-I) is a kind of human genetic disorders and is caused by the deficiency of a microsomal protein, glucose-6-phosphatase-${\alpha}$ ($G6Pase-{\alpha}$) or glucose-6-phosphate transporter (G6PT) responsible for glucose homeostasis, leading to GSD-Ia or GSD-Ib, respectively. This review summarizes cell deaths in GSD-I and mostly focuses on current knowledge of the neutrophil apoptosis in GSD-Ib based upon ER stress and redox signaling.

• Kidney Research and Clinical Practice
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• 제35권2호
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• pp.69-77
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• 2016

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease, and its pathogenesis is complex and has not yet been fully elucidated. Abnormal glucose and lipid metabolism is key to understanding the pathogenesis of DN, which can develop in both type 1 and type 2 diabetes. A hallmark of this disease is the accumulation of glucose and lipids in renal cells, resulting in oxidative and endoplasmic reticulum stress, intracellular hypoxia, and inflammation, eventually leading to glomerulosclerosis and interstitial fibrosis. There is a growing body of evidence demonstrating that dysregulation of 50 adenosine monophosphate-activated protein kinase (AMPK), an enzyme that plays a principal role in cell growth and cellular energy homeostasis, in relevant tissues is a key component of the development of metabolic syndrome and type 2 diabetes mellitus; thus, targeting this enzyme may ameliorate some pathologic features of this disease. AMPK regulates the coordination of anabolic processes, with its activation proven to improve glucose and lipid homeostasis in insulin-resistant animal models, as well as demonstrating mitochondrial biogenesis and antitumor activity. In this review, we discuss new findings regarding the role of AMPK in the pathogenesis of DN and offer suggestions for feasible clinical use and future studies of the role of AMPK activators in this disorder.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1300-1308
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• 2012

The 5'-adenosine monophosphate-activated protein kinase (AMPK) is a key part of a kinase-signaling cascade that acts to maintain energy homeostasis. The objective of this experiment was to investigate the possible effects of fasting and refeeding on the gene expression of hypothalamic AMPK, some appetitive regulating peptides and lipid metabolism related enzymes. Seven-day-old male broiler (Arbor Acres) chicks were allocated into three equal treatments: fed ad libitum (control); fasted for 24 h; fasted for 24 h and then refed for 24 h. Compared with the control, the hypothalamic gene expression of $AMPK{\alpha}2$, $AMPK{\beta}1$, $AMPK{\beta}2$, $AMPK{\gamma}1$, Ste20-related adaptor protein ${\beta}$ ($STRAD{\beta}$), mouse protein $25{\alpha}$ ($MO25{\alpha}$) and agouti-related peptide (AgRP) were increased after fasting for 24 h. No significant difference among treatments was observed in mRNA levels of $AMPK{\alpha}1$, $AMPK{\gamma}2$, LKB1 and neuropeptide Y (NPY). However, the expression of $MO25{\beta}$, pro-opiomelanocortin (POMC), corticotropin-releasing hormone (CRH), ghrelin, fatty acid synthase (FAS), acetyl-CoA carboxylase ${\alpha}$ ($ACC{\alpha}$), carnitine palmitoyltransferase 1 (CPT-1) and sterol regulatory element binding protein-1 (SREBP-1) were significantly decreased. The present results indicated that 24 h fasting altered gene expression of AMPK subunits, appetite regulation peptides and lipometabolism related factors in chick's hypothalamus; the hypothalamic FAS signaling pathway might be involved in the AMPK regulated energy homeostasis and/or appetite regulation in poultry.

• 한국식품영양학회지
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• 제29권2호
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• pp.290-299
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• 2016

This study was conducted to determine the association between dietary calcium intake and biomarkers related to lipid and glucose metabolism and inflammation in Korean patients with type 2 diabetes. Seventy-five subjects (41 males, 34 females) were recruited from a group of patients who had visited the department of endocrine medicine. Data on anthropometric characteristics, clinical indices such as hemoglobin A1c and C-reactive protein (CRP), and dietary nutrient intakes were collected. Subjects were divided into three groups on the basis of their calcium intake [< EAR (below estimated average requirement), EAR-RNI (between EAR and recommended nutrient intake), > RNI (above RNI)]. Average calcium intake of < EAR, EAR-RNI, > RNI groups were $462.7{\pm}18.7$, $649.7{\pm}12.8$, and $895.7{\pm}21.7mg$, respectively. Energy intake was not different among groups but intakes of protein, total and saturated fatty acids were significantly higher in > RNI group than < EAR group. Analysis of covariance revealed that HDL cholesterol level was significantly higher in EAR-RNI group, as compared to < EAR group after adjustment with confounders such as age, sex, BMI and energy intake (p < 0.05). Levels of CRP and homeostasis model assessment 2-insulin resistance (HOMA2-IR) were significantly lower in EAR-RNI group. Total cholesterol level was higher in EAR-RNI and > RNI groups, although within the normal range. Our results suggest that dietary calcium intake may influence the levels of HDL-cholesterol, CRP and HOMA2-IR and subsequently, help management/treatment of type 2 diabetes patients.

• Mycobiology
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• 제47권3호
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• pp.346-349
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• 2019

AMP-activated protein kinase sucrose non-fermenting 1 (Snf1) is a representative regulator of energy status that maintains cellular energy homeostasis. In addition, Snf1 is involved in the mediation of environmental stress such as salt stress. Snf1 regulates metabolic enzymes such as acetyl-CoA carboxylase, indicating a possible role for Snf1 in metabolic regulation. In this article, we performed nuclear magnetic resonance (NMR) spectroscopy to profile the metabolic changes induced by Snf1 under environmental stress. According to our NMR data, we suggest that Snf1 plays a role in regulating cellular concentrations of a variety of metabolites during environmental stress responses.

• 반도체디스플레이기술학회지
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• 제22권4호
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• pp.7-12
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• 2023

The edge ring placed on the outside of the electrostatic chuck (ESC) is a key component for protecting the ESC and controlling the etching uniformity of the edge of the wafer. Therefore, it is very important to understand the etching phenomenon of edge rings for edge ring management and equipment homeostasis. In this study, a specimen with SiO₂ hard mask and underlying Si mold was installed on the edge ring surface and the etching results were measured by varying the edge ring 2MHz RF power. By developing PI-VM model with high prediction accuracy and analyzing the roles of key parameters in the model, we were able to evaluate the effect of plasma and sheath characteristics around the edge ring on edge ring erosion. This analysis method provided information necessary for edge ring maintenance and operation.

• 동서간호학연구지
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• 제3권1호
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• pp.7-16
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• 1998

This paper reviewed the concept of the energy flow in east and west. The differences in the views of the energy flow between oriental and western thought were compaired according to the ontological point of view. Human body take up energy and material on open system which maintains homeostasis. Human and environment are continuously interacting in a state of co-existence. Human has energy field called "aura" and seven chakra in energy outflow moving came as meridian. Qi is an invisible cosmic energy helping the fundamental human activity and changes. The basic action of Qi is helping the human growth and development, maintain the body temperature and preventing the intrusion of microorganism. In the normal healthy organism, all are maintained in balance and in a continuous circulation of Qi, while illness is the result of the disturbed Qi flow in the aspect of Qi-theory. Although there are differences between oriental and western medicine in approaches to clients, the basic point of view and philosophy have many similarities on fundamental level. An understanding of the basic thought of energy flow and oriental concept of energy flow implies a more comprehensive meaning than the perspective of unitary transformation discussed in modern western thought of energy flow. Now we should avoid narrow view of energy concept and regard energy flow as an integrated concept with Korean culture. Regarding Qi-theory which provides a comprehensive and humanistic and ethical foundation for nursing philisophy through this overview, it is hoped that a contribution will be made to the development of nursing intervention which is suitable to Korean context.

• 의정연구
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• 제23권1호
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• pp.151-185
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• 2017

서울의 '원전하나 줄이기(2012)' 정책은 성공적인 도시 에너지 정책이자, 에너지 전환(energy transition)의 성공사례로 소개되고 있다. 하지만, 본 정책의 이른바 '목표달성'이 어떻게 가능했는지에 대해서는 구체적으로 설명된 바가 없다. 본 연구는 원전하나 줄이기 정책의 높은 수준의 성과가 가능한 이유로, 정책인식, 정책목표, 정책수단 및 정책평가 등의 체계 구성요인 간의 조화를 유지할 수 있었던 서울시의 거버넌스 역량을 핵심 요인으로 제시하였다. 이러한 거버넌스 관점의 설명은 정책의 장(policy arena)으로서의 도시의 중요성을 부각시키고, 도시정부의 역량에 따라 체계의 전반적인 전환 과정에서 내적 일관성을 유지하며 정책체계로서의 항상성과 지속성을 유지할 수 있음을 보여준다. 경성에너지체계로 정의되는 합리성-효율성-중앙집권적 에너지체계는 원전하나 줄이기 정책의 시행과 더불어 연성에너지체계로 이행되기 시작하였다. 에너지체계 운영의 주체로서, 체계전환을 관리하는 서울시의 역량은 따라서 가장 중요한 설명변수가 된다.