• Nutrition Research and Practice
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• 제9권4호
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• pp.370-378
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• 2015

BACKGROUND/OBJECTIVES: Athletes generally desire changes in body composition in order to enhance their athletic performance. Often, athletes will practice chronic energy restrictions to attain body composition changes, altering their energy needs. Prediction of resting metabolic rates (RMR) is important in helping to determine an athlete's energy expenditure. This study compared measured RMR of athletic and non-athletic adolescents with predicted RMR from commonly used prediction equations to identify the most accurate equation applicable for adolescent athletes. SUBJECTS/METHODS: A total of 50 athletes (mean age of $16.6{\pm}1.0years$, 30 males and 20 females) and 50 non-athletes (mean age of $16.5{\pm}0.5years$, 30 males and 20 females) were enrolled in the study. The RMR of subjects was measured using indirect calorimetry. The accuracy of 11 RMR prediction equations was evaluated for bias, Pearson's correlation coefficient, and Bland-Altman analysis. RESULTS: Until more accurate prediction equations are developed, our findings recommend using the formulas by Cunningham (-29.8 kcal/day, limits of agreement -318.7 and +259.1 kcal/day) and Park (-0.842 kcal/day, limits of agreement -198.9 and +196.9 kcal/day) for prediction of RMR when studying male adolescent athletes. Among the new prediction formulas reviewed, the formula included in the fat-free mass as a variable [$RMR=730.4+15{\times}fat-free\;mass$] is paramount when examining athletes. CONCLUSIONS: The RMR prediction equation developed in this study is better in assessing the resting metabolic rate of Korean athletic adolescents.

• IMMUNE NETWORK
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• 제6권4호
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• pp.169-178
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• 2006

Background: Adipose tissues were initially introduced as energy storages, but recently they have become famous as an endocrine organ which produces and secretes various kinds of molecules to make physiologic and metabolic changes in human body. It has been studied that these molecules are secreted in abundance as the adipose tissue becomes bigger along with obesity. Furthermore, it has been found that they are mediating systemic inflammation and generation of metabolic diseases such as type 2 diabetes and atherosclerosis. On the basis of these, we studied previous papers which have been researched about the interaction between preadipocytes and macrophages, adipose tissues and lymph nodes, and adipose tissue secreting molecules. Results: Firstly, preadipocytes and macrophages are expressing similar transcriptomes and proteins, and preadipocytes can be converted to mature macrophages which have phagocytic activity. Moreover, the monocytes, which initially located in the bone marrow, are filtrated to the adipose tissue by monocyte chemotatic protein-1 and are matured to macrophages by colony stimulating factor-1. Secondly, adipose tissues and their associated lymph nodes are interacting each other in terms of energy efficiency. Lymph nodes promote lipolysis in adipose tissues, and polyunsaturated fatty acids in adipocytes become energy sources for dendritic cells. Lastly, adipose tissues produce and secrete proinflammatory molecules such as leptin, adiponectin, TNF-${\alpha}$, IL-6, and acute phase proteins, which induce the inflammation and potentially generate metabolic diseases. Conclusion: According to these, we can link adipose tissues to inflammation, but we need to affirm the actual levels and roles of adipose tissue-derived proinflammatory molecules in human body.

• 산업경영시스템학회지
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• 제27권3호
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• pp.90-96
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• 2004

The objective of this study was to develop a model for safe work load based on a physiological model of metabolic energy of manual material handling tasks. Fifteen male subjects voluntarily participated in this study. Lifting activities with four different weights, 0, 8, 16, 24kg, and four different working frequencies (2, 5, 8, 11 lifts/min) for a lifting range from floor to the knuckle height of 76cm were considered. Oxygen consumption rates and heart rates were measured during the performance of sixteen different lifting activities. Simplified predictive equations for estimating the oxygen consumption rate and the heart rate were developed. The oxygen consumption rate and the heart rate could be expressed as a function of task variables; frequency and the weight of the load, and a personal variable, body weight, and their interactions. The coefficients of determination ($r^2$) of the model were 0.9777 and 0.9784, respectively, for the oxygen consumption rate and the heart rate. The model of oxygen consumption rate was modified to estimate the work load for the given oxygen consumption rate. The overall absolute percent errors of the validation of this equation for work load with the original data set was 39.03%. The overall absolute percent errors were much larger than this for the two models based on the US population. The models for the oxygen consumption rate and for the work load developed in this study work better than the two models based on the US population. However, without considering the biomechanical approach, the developed model for the work load and the two US models are not recommended to estimate the work loads for low frequent lifting activities.

• 한국식생활문화학회지
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• 제35권3호
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• pp.294-301
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• 2020

The purpose of this study was to investigate the association between dietary macronutrient intakes and prevalence of metabolic syndrome (MetS) in Korean adults. Data were obtained from the Korean National Health and Nutrition Examination Survey (2013-2017), and a total of 11,600 Korean adults (4,918 men, 6,682 women) aged 50 years and older were analyzed. The daily intakes and percentages of energy from carbohydrates or fat in men or women with MetS were significantly lower than in normal subjects, respectively. High carbohydrate or fat percentages were negatively associated with MetS based on adjusted odds ratios (OR) of 0.804 in men (p=0.034) and 0.820 in women (p=0.045), respectively. A high percentage of energy from carbohydrates was positively associated with reduced waist circumference, diastolic blood pressure, triglyceride and high-density lipoprotein (HDL) cholesterol in men. On the other hand, a high percentage of energy from fat was positively related with elevated HDL cholesterol and reduced triglycerides in women. In conclusion, our study indicates that high carbohydrate or fat intake is associated with risk of MetS in Korean men or women aged 50 years and older, respectively. Further prospective studies are necessary to elucidate the association between macronutrient intakes and MetS among Korean adults according to age.

• BMB Reports
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• 제45권7호
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• pp.396-401
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• 2012

Overnutrition is one of the major causes of non-alcoholic fatty liver disease (NAFLD). NAFLD is characterized by an accumulation of lipids (triglycerides) in hepatocytes and is often accompanied by high plasma levels of free fatty acids (FFA). In this study, we compared the energy metabolism in acute steatotic and non-steatotic primary mouse hepatocytes. Acute steatosis was induced by pre-incubation with high concentrations of oleate and palmitate. Labeling experiments were conducted using [$U-^{13}C_5$,$U-^{15}N_2$] glutamine. Metabolite concentrations and mass isotopomer distributions of intracellular metabolites were measured and applied for metabolic flux estimation using transient $^{13}C$ metabolic flux analysis. FFAs were efficiently taken up and almost completely incorporated into triglycerides (TAGs). In spite of high FFA uptake rates and the high synthesis rate of TAGs, central energy metabolism was not significantly changed in acute steatotic cells. Fatty acid ${\beta}$-oxidation does not significantly contribute to the detoxification of FFAs under the applied conditions.

• 운동영양학회지
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• 제25권4호
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• pp.1-9
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• 2021

[Purpose] This study analyzed data from the 7^th Korean National Health and Nutrition Examination Survey (2016-2018) to compare the differences in energy intake and physical activity (PA) levels in middle-aged Korean men aged 40-59 years according to household type and the presence of metabolic syndrome (MetS). [Methods] Data from 2,266 young adults (aged >39 years and <60 years) were obtained from the KNHANES. We analyzed the differences in energy intake and PA levels according to household type and MetS. The presence or absence of MetS was determined by measuring waist circumference, blood pressure, fasting blood glucose, triglyceride, and HDL-C levels. [Results] Regarding total nutritional intake, no relationship with MetS was observed regardless of household type (interaction between MetS and household type: p = 0.875). No differences in total PA were observed between multiple- and single-person households (interaction between MetS and household type: p = 0.122). The relationship between MetS and MetS components according to nutritional intake showed that participants with a higher energy intake had a 27% lower prevalence of low high-density lipoprotein cholesterol (HDL-C) (p < 0.05) and a 36% higher prevalence of high blood pressure (p < 0.01). The relationship between MetS and MetS components according to the PA level showed significantly reduced prevalence of MetS by approximately 39%, 35%, and 43% (p < 0.01, 0.01, and 0.001) in subjects who were somewhat active, active, and very active, respectively, compared to inactivity. [Conclusion] Middle-aged men showed no difference in nutritional intake and PA between multiple- and single-person households. However, the risk of MetS was significantly higher in participants with approximately 1.5 times the energy intake compared to the group with the lowest energy intake. Moreover, higher levels of PA had a marked positive effect on the risk factors and prevalence of MetS. Therefore, we suggest that reducing the total energy intake and increasing total PA are important for preventing MetS in middle-aged men regardless of household type.

• 대한지역사회영양학회지
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• 제20권6호
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• pp.460-467
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• 2015

Objectives: Excess sodium intake has been linked to obesity and obesity-related indices. However, the scientific evidence for this association is inadequate. The purpose of this study was to investigate the association between urinary sodium excretion and obesity-related indices among Korean adults. Methods: A convenience sample of 120 subjects (60 obese and 60 non-obese subjects) were recruited applying frequency matching for sex and age between two groups. Sodium intake level was assessed through 24-hour urine collection. Obesity-related metabolic risk factors, including fasting blood lipid indices, subcutaneous and visceral fat through computed tomography (CT), insulin resistance indices, blood pressure and liver enzymes were measured in all subjects. These obesity-related metabolic risk factors were compared between obese and non-obese group according to sodium excretion levels (<110 mEq/day, 110~180 mEq/day, >180 mEq/day). Results: After adjusting for age, gender, health behaviors (smoking, exercise, drinking), and energy intake, several obesity-related metabolic risk factors, including abdominal circumference, body fat percentage, subcutaneous and visceral fat, triglyceride, and systolic blood pressure were found to be significantly deteriorated as the sodium excretion level increases. In addition, multivariate adjusted-odds ratios of abdominal obesity, high blood triglyceride, and high blood pressure were found significantly higher in the highest sodium excretion group compared to the lowest group. The mean number of metabolic syndrome risk factors was also significantly greater in the highest sodium excretion group than in the lowest group. Conclusions: The current study findings suggested that high sodium intake can affect obesity and metabolic syndrome risk negatively, implying the necessity of future research on low-sodium diet intervention in relation to obesity and related health problems.

• 동아시아식생활학회지
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• 제23권3호
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• pp.282-296
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• 2013

The study classified 83 obese adults by constitution and had them follow a strict diet according to their constitution in order to see if the Yin-Yang method would be effective on the metabolic syndrome, which is one of the main causes of death in Korea. Overall, the application of both Yin and Yang methods improved the following factors: weight, body fat percentage, systolic blood pressure, diastolic pressure, neutral fats and total cholesterol. In particular, the Yin constitution group of men showed more improvements than the Yang constitution group. Furthermore, waist circumference and the prevalence rate of systolic blood pressure, diastolic pressure, total cholesterol and metabolic syndrome were decreased noticeably. Total energy intake was increased in both men and women after the constitutional diet, along with the increase of nutrient intake, such as dietary fiber, vitamins and minerals, among others. Among various nutrients, vitamin A, vitamin C, thiamine, vitamin B6, folic acid, calcium, phosphorus, potassium, magnesium and iron intake were increased noticeably after the constitutional diet. In addition, subjects' intake of all nutrients, except for magnesium, satisfied the nutrition intake standards. Further, the nutrients adequacy ratio (NAR) and the mean adequacy ratio (MAR) improved for both men and women. The intake of potatoes, starch, greens and mushrooms increased noticeably, whereas the intake of meat, dairy, drinks and alcohol decreased after the constitutional diet. For the Yin constitution, the intake of Yin foods noticeably decreased, where as the intake of Yang foods decreased for the Yang constitution. In conclusion, the constitutional diet effectively improves the metabolic syndrome. Among many nutrients, the intake of dietary fiber, vitamins A, C and E, potassium and magnesium is positively associated with the improvement of metabolic syndrome biomarkers.

• KSBB Journal
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• 제20권6호
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• pp.464-469
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• 2005

가정쓰레기 매립지 토양에서 분리된 Enterobacter sp. SNU-1453은 Enteric bacteria에 속하는 종(species)으로서 혐기 발효 시 효과적으로 수소를 생산하였다. 이러한 fermentative bacteria는 여러 가지 외부 요인에 의해 다른 metabolism을 나타내어 수소생산량에 영향을 준다. 혐기 발효가 진행됨에 따라 배지의 pH가 급격히 감소하여 미생물 성장과 수소생산에 영향을 미치므로, pH에 따른 metabolism변화를 관찰함으로써 수소생산을 극대화하기 위한 최적 pH 조건을 선정하여 제어할 필요가 있다. 본 연구에서는 수소생산에 대한 pH의 효과 및 pH 제어에 따른 metabolic flux를 분석하였다. 실험 결과 이 분리 균주는 매우 넓은 영역의 pH(4-7.5)에서도 수소를 생산하였으며, pH 7에서 가장 높은 수소생산량을 나타내었다. pH 7로의 제어는 butanediol pathway로부터 수소 생산에 더 유리한 mixed acid fermentation pathway로 metabolic flux를 변화시킴을 알 수 있었다.

• Nutrition Research and Practice
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• 제13권6호
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• pp.488-497
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• 2019

BACKGROUND/OBJECTIVES: There are various factors that affect metabolic abnormalities related to obesity. The purpose of this study is to analyze the differences in dietary intakes and body compositions of obese women according to metabolic risks and to classify them as metabolically healthy obese (MHO) or metabolically abnormal obese (MAO). SUBJECTS/METHODS: This study was conducted on 59 obese Korean women aged 19 to 60 years. NCEP-ATPIII criteria were applied and the women classified as MHO (n = 45) or MAO (n = 14). Body composition of each subject was measured by using dual-energy x-ray absorptiometry (DEXA). Three-day food records were used to analyze dietary intake. Eating habits and health-related behaviors were determined through questionnaires. Indirect calorimetry was used to measure resting metabolic rate and respiratory rate. RESULTS: The average age of the subjects was 43.7 years. The analysis of body composition according to phenotype revealed significantly higher body fat mass (P < 0.05), arm fat mass (P < 0.05), and android fat mass (P < 0.05), as measured by DEXA, in the MAO group than in the MHO group. There was no significant difference in the dietary intake of the two groups. However, eating behaviors differed. Compared to the MHO group, the MAO women had a shorter meal time (less than 10 minutes), a preference of oily foods, and a tendency to eat until full. Therefore, the eating habits of MHO women were more positive than those of MAO women. CONCLUSIONS: The results suggest that fat distribution in each body region affects various metabolic abnormalities. A high level of arm fat mass in obese Korean women may increase metabolic risk. In addition, eating habits of obese Korean women are considered to be environmental factors affecting the metabolic phenotype of obese Korean women.