• 한국ITS학회 논문지
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• 제22권6호
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• pp.223-229
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• 2023

본 논문에서는 3.6 ~ 4.0 GHz 대역의 6단의 방사형 스터브 공진기를 갖는 SPDT(Single Pole Double Throw) 스위치를 제안한다. SPDT 스위치는 무선통신회로 설계 툴인ADS(Advanced Design Software) 시뮬레이션을 통해 pcb 기판 위에 제작되었다. SPDT 스위치 측정결과, 격리도는 평균 90 dB, 삽입 손실은 1.5 dB 정도인 것으로 나타났다. 본 논문에서 제안한 스위치는 현재 연구되어 있거나 상용화 되어 있는 비슷한 구조의 스위치들보다 해당 주파수 대역에서 평균 20dB 이상의 고격리도를 나타내고 있다. 제안된 SPDT 스위치는 WiMAX, LTE/5G, WiFi 및 HyperLAN과 같은 다중 대역 RF front-end 시스템에 적용 가능하다.

• Nutrition Research and Practice
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• 제8권6호
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• pp.644-654
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• 2014

BACKGROUND/OBJECTIVES: Although preclinical studies suggest that garlic has potential preventive effects on cardiovascular disease (CVD) risk factors, clinical trials and reports from systematic reviews or meta-analyses present inconsistent results. The contradiction might be attributed to variations in the manufacturing process that can markedly influence the composition of garlic products. To investigate this issue further, we performed a meta-analysis of the effects of garlic powder on CVD risk factors. MATERIALS/METHODS: We searched PubMed, Cochrane, Science Direct and EMBASE through May 2014. A random-effects meta-analysis was performed on 22 trials reporting total cholesterol (TC), 17 trials reporting LDL cholesterol (LDL-C), 18 trials reporting HDL cholesterol (HDL-C), 4 trials reporting fasting blood glucose (FBG), 9 trials reporting systolic blood pressure (SBP) and 10 trials reporting diastolic blood pressure (DBP). RESULTS: The overall garlic powder intake significantly reduced blood TC and LDL-C by -0.41 mmol/L (95% confidence interval [CI], -0.69, -0.12) (-15.83 mg/dL [95% CI, -26.64, -4.63]) and -0.21 mmol/L (95% CI, -0.40, -0.03) (-8.11 mg/dL [95% CI, -15.44, -1.16]), respectively. The mean difference in the reduction of FBG levels was -0.96 mmol/L (95% CI, -1.91, -0.01) (-17.30 mg/dL [95% CI, -34.41, -0.18]). Evidence for SBP and DBP reduction in the garlic supplementation group was also demonstrated by decreases of -4.34 mmHg (95% CI, -8.38, -0.29) and -2.36 mmHg (95% CI, -4.56, -0.15), respectively. CONCLUSIONS: This meta-analysis provides consistent evidence that garlic powder intake reduces the CVD risk factors of TC, LDL-C, FBG and BP.

• Journal of Nutrition and Health
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• 제48권1호
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• pp.1-8
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• 2015

자색고구마 열수추출물의 간 보호 기능을 확인하기 위해 C57BL/6 마우스를 사용하여 시험하였다. 지방간 유도를 위해 8주간 고지방/콜레스테롤 식이를 급여하였으며, 자색고구마 열수추출물은 1.25, 2.5, 5%의 수준으로 식이에 함께 넣어 같은 기간 동안 제공하였다. 간 조직의 병리학적 분석, 혈장 ALT 활성도, 간 및 혈장의 TC 수준을 바탕으로 비알콜성 지방간 모델이 형성되었음을 확인하였다. 고지방/콜레스테롤 식이의 급여는 식이섭취량을 감소시켜 총 에너지 섭취량은 시험군간 차이가 없었으나, 포화지방을 급원으로 하였을 때 지방세포의 비대와 혈장 TC, 간 TC, 간의 지방구를 증가시키는 것으로 관찰되었다. 한편 자색고구마 열수추출물을 고지방/콜레스테롤 식이와 함께 섭취시킨 결과, 고지방/콜레스테롤 식이로 인한 지질대사 이상을 유의하게 변화시키지 못해 혈액 및 간 손상 지표를 개선시키지 못하였으나, 지방조직의 크기는 작게 유지하고 간의 지방구 형성은 억제하는 것으로 관찰되었다. 이상의 결과로 자색고구마 열수추출물은 지질대사 개선을 통해 간 보호 효과를 갖음을 알 수 있었다. 향후에는 자색고구마 열수추출물이 지방세포-간의 상호 지질대사에 미치는 영향을 추가적으로 연구해야 할 것으로 사료된다.

• Nutrition Research and Practice
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• 제11권3호
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• pp.232-239
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• 2017

BACKGROUND/OBJECTIVES: Increased consumption of instant noodles has recently been reported to be positively associated with obesity and cardiometabolic syndrome in South Korea, which has the highest per capita instant noodle consumption worldwide. This study aimed to investigate the association between instant noodle consumption and cardiometabolic risk factors among college students in Seoul. SUBJECTS/METHODS: The study subjects consisted of 3,397 college students (1,782 male; 1,615 female) aged 18-29 years who participated in a health checkup. Information on instant noodle consumption was obtained from the participants' answers to a question about their average frequency of instant noodle intake over the 1 year period prior to the survey. RESULTS: Statistical analysis using a general linear model that adjusted for age, body mass index, gender, family income, health-related behaviors, and other dietary factors important for cardiometabolic risk, showed a positive association between the frequency of instant noodle consumption and plasma triglyceride levels, diastolic blood pressure, and fasting blood glucose levels in all subjects. Compared to the group with the lowest frequency of instant noodle intake (${\leq}1/month$), the odds ratio for hypertriglyceridemia in the group with an intake of ${\geq}3/week$ was 2.639 [95% confidence interval (CI), 1.393-5.000] for all subjects, while it was 2.149 (95% CI, 1.045-4.419) and 5.992 (95% CI, 1.859-21.824) for male and female students, respectively. In female students, diastolic blood pressure was also higher among more frequent consumers of instant noodles. CONCLUSIONS: Our results suggest that frequent consumption of instant noodles may be associated with increased cardiometabolic risk factors among apparently healthy college students aged 18-29 years.

• Journal of Nutrition and Health
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• 제46권3호
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• pp.226-238
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• 2013

Omega-3 polyunsaturated fatty acids are essential fatty acids because humans cannot synthesize them de novo and must obtain them in their diet. Fish and fish oil are rich sources of omega-3 fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Significant evidence of the beneficial role of dietary intake of omega-3 fatty acids in blood flow has been reported and putative mechanisms for improvement of blood flow include anti-thrombotic effects, lowered blood pressure, improved endothelial function, and anti-atherogenic effects. Edible oils containing omega-3 fatty acids were registered as functional ingredients in the Korea Health Functional Food Code. Although omega-3 fatty acids have been evaluated by the Korea Food and Drug Administration (KFDA) based on scientific evidence, periodic re-evaluation may be needed because emerging data related to omega-3 fatty acids have accumulated. Therefore, in this study, we re-evaluated scientific evidence for the effect of omega-3 fatty acids as a functional ingredient in health functional food on improvement of blood flow. A comprehensive literature search was conducted for collection of relevant human studies using the Medline and Cochrane, KISS, and IBIDS databases for the years 1955-2012. Search keywords were used by combination of terms related to omega-3 fatty acids and blood flow. The search was limited to human studies published in Korean, English, and Japanese. Using the KFDA's evidence based evaluation system for scientific evaluation of health claims, 112 human studies were identified and reviewed in order to evaluate the strength of the evidence supporting a relation between omega-3 fatty acids and blood flow. Among 112 studies, significant effects on improvement of blood flow were reported in 84 studies and the daily intake amount was ranged from 0.1 to 15 g. According to this methodology of systematic review, we concluded that there was possible evidence to support a relation between omega-3 fatty acid intake and blood flow. However, because inconsistent results have recently been reported, future studies should be monitored.

• Nutrition Research and Practice
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• 제14권4호
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• pp.322-333
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• 2020

BACKGROUND/OBJECTIVES: Arterial stiffness and endothelial dysfunction are 2 of the independent predictors for cardiovascular disease, while Acanthopanax senticosus Harms (ASH) is a traditional medicinal plant that can improve cardiovascular health. This study aimed to investigate the efficacy of the fruit of ASH on vascular function in apparently healthy subjects. SUBJECTS/METHODS: A 12-week, randomized, double-blind, placebo-controlled design, consisting of healthy adults with at least 2 of the following 3 conditions: borderline high blood pressure (BP; 120 mmHg ≤ systolic BP ≤ 160 mmHg or 80 mmHg ≤ diastolic BP ≤ 100 mmHg), smoking (≥10 cigarettes/day), and borderline blood lipid levels (220 ≤ total cholesterol ≤ 240, 130 ≤ low density lipoprotein cholesterol ≤ 165, or 150 ≤ triglyceride ≤ 220 mg/dL). Randomly assigned 76 subjects who received a placebo or 2 doses of ASH fruit (low, 500 mg/day; high, 1,000 mg/day) completed the intervention. Brachial-ankle pulse wave velocity (baPWV), flow-mediated dilation, carotid intima-media thickness, and BP were measured both at baseline and following the 12-week intervention. Endothelial nitric oxide synthase (eNOS) phosphorylation was assessed by western blotting. RESULTS: Compared with the placebo group, the low-dose group showed more significant changes after the 12-week intervention period in terms of systolic BP (0.1 vs. -7.7 mmHg; P = 0.044), baPWV (31.3 vs. -98.7 cm/s; P = 0.007), and the ratio of phospho-eNOS/eNOS (0.8 vs. 1.22; P = 0.037). CONCLUSIONS: These results suggest that ASH fruit extract at 500 mg/day has the potential to improve BP and arterial stiffness via endothelial eNOS activation in healthy adults with smoking and the tendency of having elevated BP or blood lipid parameters.

• Journal of Nutrition and Health
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• 제51권2호
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• pp.132-139
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• 2018

본 연구는 일반병동에 입원하여 3일 이상 경장영양을 시행한 성인 환자 95명을 대상으로 영양집중지원팀의 중재 효과를 평가하기 위해 영양중재를 받은 중재군과 받지 못한 군으로 분류하여 열량 및 단백질 지원율과 생화학적 지표를 비교 분석 하였다. 연구결과를 통해 환자의 입원초기부터 적절한 영양관리를 계획하고, 영양집중지원팀의 영양중재로 체계적인 관리를 실시하면 환자의 영양상태가 개선되는 것을 확인할 수 있었다. 결론적으로 영양불량 문제가 있는 환자에게 영양집중지원팀의 중재를 받아 문제를 개선할 수 있도록 절차를 마련한다면, 이는 환자의 임상적 치료에 긍정적인 영향을 줄 것으로 생각된다. 본 연구는 국내에서 경장영양을 시행한 일반병동 환자를 대상으로 영양집중 지원팀의 중재 효과에 대한 초기 연구이며, 집중영양치료료 수가 신설 이후 진행된 연구다. 추후 일반병동 환자를 대상으로 영양집중지원팀의 중재효과에 대한 연구가 다양하게 시행된다면 의료진의 관심이 증대 될 것이고, 나아가 영양집중지원팀의 중재를 통해 진료의 질을 높일 수 있을 것이다.

• Nutrition Research and Practice
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• 제12권5호
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• pp.371-377
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• 2018

BACKGROUND/OBJECTIVES: Elevation of postprandial lipemia characterized by a rise in triglyceride (TG)-rich lipoproteins can increase the risk of atherogenesis. The objective of this study was to investigate postprandial lipemia response to a single dietary fat/sugar load test and monitor beneficial changes induced by the consumption of Platycodi radix (AP) beverage in healthy subjects. SUBJECTS/METHODS: A total of 52 subjects were randomly assigned to either placebo or AP beverage group with a high-fat shake in a randomized controlled crossover trial. Postprandial blood was collected at 0, 1, 2, 4, and 6 h and analyzed for TG and lipoprotein lipase mass. Inhibition of pancreatic lipase was determined in vitro. RESULTS: AP inhibited pancreatic lipase activity in vitro ($IC_{50}=5mg/mL$). Compared to placebo beverage, AP beverage consumption with a high-fat shake induced significant increase of plasma lipoprotein lipase mass (P = 0.0111, ${\beta}$ estimate = 4.2948) with significant reduction in very low-density lipoprotein (VLDL) TG concentration (P = 0.038, ${\beta}$ estimate = -52.69) at 6 h. Based on significant correlation between high-fat dietary scores MEDFICTS and postprandial TG responses in VLDL (P = 0.0395, r = 0.2127), subgroup analysis revealed that 6 h-postprandial VLDL TG response was significantly decreased by AP consumption in subjects with MEDFICTS ${\geq}40$ (P = 0.0291, ${\beta}$ estimate = -7214). CONCLUSIONS: AP beverage might have potential to alleviate postprandial lipemia through inhibiting pancreatic lipase activity and elevating lipoprotein lipase mass. Subgroup analysis revealed that subjects with high-fat dietary pattern could be classified as responders to AP beverage among all subjects.

• Journal of Nutrition and Health
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• 제48권2호
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• pp.133-139
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• 2015

본 연구는 갈근과 지황 복합물과 유산소 운동이 난소절제로 갱년기를 유도한 흰 쥐에서 나타나는 지질 및 당대사 이상에 미치는 영향을 확인하였다. 난소절제 후 8주간 AIN-76A 식이를 급여한 결과 체중증가량, 식이섭취량, 체 지방, 혈장 LDL-C, 공복혈당 증가를 통해 갱년기 동물 모델이 유도되었음을 확인할 수 있었다. 갈근과 지황 복합물과 유산소 운동은 서로 다른 기전으로 에스트로겐 분비 저하로 나타나는 비만 및 대사이상을 정상화하는 유익한 결과를 나타냈다. 지방 조직에서 확인된 관련 기전으로는 갈근과 지황 복합물로 인한 아디포넥틴 유전자 발현 증가 및 렙틴저항 억제, 유산소 운동으로 인한 아디포넥틴 및 인슐린 수용체 유전자 발현 증가, 갈근과 지황 복합물 및 유산소 운동의 병행으로 인한 아디포넥틴 유전자 발현 증가 상승효과가 관찰되었다. 이상의 결과로 갈근과 지황 복합물과 유산소 운동의 병행은 폐경기 에스트로겐 결핍으로 인한 대사이상을 개선하는 효과가 있을 것으로 기대한다. 향후에는 폐경기 유도 동물모델의 개선과 함께 단백질 및 신호전달분자 수준에서 추가적인 기전연구가 필요할 것으로 사료된다.

• Journal of Nutrition and Health
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• 제47권4호
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• pp.236-246
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• 2014

호두의 혈중 지질 수준 및 혈관 건강 개선 기능성을 평가하기 위하여 메타 분석을 실시하였다. 2014년 7월 9일 기준으로 DB 검색을 통해 426건의 자료를 수집하여, 선정/제외 기준에 따라 선별한 결과 총 19건 (n = 1,040)의 연구가 분석에 포함되었다. 호두를 일상 식사에서 일부 지방 급원 또는 열량을 대체하여 섭취하였을 때, 총 콜레스테롤, 저밀도 콜레스테롤, 중성지방 수준 및 혈류 매개 혈관 확장능을 각각 -0.124 mmol/l, -0.085 mmol/l, -0.080 mmol/l, +1.313 % 수준으로 대조군 대비 유의하게 개선시키는 것으로 분석되었다.