• Tuberculosis and Respiratory Diseases
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• v.46 no.6
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• pp.836-845
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• 1999

Background : Obesity is present in the majority of adult patients with obstructive sleep apnea(OSA) and is considered to be a major risk factor for its development. A reduction in body weight has been associated with substantial improvement in the severity of apnea. However, a variety of treatment strategies for obesity have yielded limited sucess. This study was done to determine resting energy expenditure(REE) in patients with obstructive sleep apnea and the correlation between the severity of sleep apnea and REE, and to investigate whether leptin influences REE and correlated with the severity of sleep apnea in 39 patients with OSA and 45 controls matched for obesity. Method : Overnight polysomnography was performed on all subjects using standard techniques. Measurements of REE were made using a Sensormedic Vmax 229 and a canopy system. Serum leptin concentration was measured by human leptin RIA kit of LINCO Research INC. Results : REE was greater in patients with OSA compared with controls, but there was no difference between the two groups on REE%. And also there was no significant correlation between anthropometric data, polysomnographic data and REE%. Serum leptin was linearly related to body mass index(BMI), apnea index, apnea hypopnea index and lowest arterial oxygen saturation($SaO_2$) but not related to REE%. Conclusion : This study suggests the followings. Firstly patients patients with sleep apnea have a pattern of obesity characterized by energy homeostasis at an elevated body weight set-point. In order to achieve a lower body weight in these patients, it may be necessary to increase energy expenditure by increasing physical activity. Secondly leptin level was not correlated with REE, suggesting that leptin may predominantly regulate body fat by altering eating behavior rather than calorigenesis. Lastly leptin level was significantly correlated with the severity of sleep apnea. These elevated level of leptin in patients of sleep apnea may be related to the obesity, however it needs further studies to determine the relationship between the severity of sleep apnea and serum leptin.

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.105-138
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• 2009

Although the decline in fertility rate is generally observed along the history of economic development throughout the world, the continuing decline hitting below the replacement level in Korea over the recent years gathered serious social concerns on the ground that it accelerates the process of population aging. The total fertility rate in Koreareached 2.08 in 1983, and gradually fell to the levels of 1.08 in 2005 and 1.26 in 2007. The policy debate over the role of the government has been focused mainly on the level of theoretical discussion without substantial basis on firm empirical evidence and the determinants of fertility. The objective of the paper is to empirically investigate the fertility effect of the female wage, which is understood as one of the most important determinants of fertility in Koreasince 1980 focusing on one aspect of fertility, namely birth spacing. Using the Korean National Fertility Survey conducted in 2006, I estimate a duration model of first and second births taking into account individual heterogeneity, which turned out to be an important factor to control for. Compared with previous studies in the literature on the Korean fertility, the study has an advantage of using the complete pregnancy history of women in a more representative sample. Unlike the previous studies, the analysis also deals with the endogeneity of marriage by treating a certain age, rather than age at marriage, as the time in which a woman becomes exposed to the risk of pregnancy. The study shares the common problem in the literature on birth spacing of lacking relevant wage information for respondents in a retrospective survey. I estimate the wage series as a function of the basic characteristics using the annual Wage Structure Survey from 1980 to 2005, which is considered as a nationally representative sample for wage information of employees. The results suggest that the increase in female wage by 10 percent leads to a decrease in second birth hazard by 0.56~0.92 percentage points and that the increase in spouse's wage by the equal amount is accompanied by the increase in second birth hazard by 0.36~1.13 percentage points. These estimates are more precisely estimated and of smaller magnitude than those presented by the previous studies. The results are robust to the different specifications of the wage equation. The simulation analysis based on the predicted values shows that about 17% of the change in the second birth hazard over the period 1980 to 2005 was due to the change in the female wage. Although there is some limitation in data, the results can be viewed as one estimate of the role of female wage on the recent fertility decline in Korea. The question raised by the paper is not a normative one of whether a government should promote childbearing but a positive one thatexplains fertility decline. Therefore, if there is a wide consensus on promoting childbearing, the finding suggests that the policies designed to reduce the opportunity cost of women in the labor market would be effective. The recent movement of implementing a wide range of family-friendly policies including child care support, maternity leave, parental leave and tax benefit in developed countries should be understood in this context.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.2
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• pp.90-94
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• 2013

Objective: To evaluate the efficacy of earlier oocyte retrieval in IVF patients with a premature LH surge on hCG day. Methods: One hundred forty IVF patients (164 cycles) with premature LH surge on hCG day were included, retrospectively. We divided them into 2 study groups: LH surge with timed ovum pick-up (OPU) 36 hours after hCG injection (group B, 129 premature cycles), and LH surge with earlier OPU within 36 hours after hCG injection (group C, 35 cycles). Control groups were tubal factor infertility without premature LH surge (group A, 143 cycles). Results: The mean age (year) was statistically higher in group C than in groups A or B ($38.2{\pm}5.4$ vs. $36.2{\pm}4.2$ vs. $36.8{\pm}4.9$, respectively; p=0.012). The serum LH levels (mIU/mL) on hCG day were significantly higher in group B and C than in group A ($22.7{\pm}14.9$ vs. $30.3{\pm}15.9$ vs. $3.2{\pm}2.9$, respectively; p>0.001). Among groups A, B, and C, 4.9%, 31.7%, and 51.4% of the cycles, respectively, had no oocytes, and the overall rates of cycle cancellation (OPU cancellation, no oocyte, or no embryos transferrable) were 15.4%, 65.9%, and 74.3%, respectively. The fertilization rate (%) was significantly higher in group B than in group C ($73.2{\pm}38.9$ vs. $47.8{\pm}42.9$, p=0.024). The clinical pregnancy rate was significantly higher in group C than in groups A and B (44.4% vs. 27.3% vs. 9.1%, respectively, p=0.021). However, the miscarriage rate was also higher in group C than in group B (22% vs. 0%, respectively, p=0.026). Conclusion: Earlier OPU may not be effective in reducing the risk of cycle cancellation in patients with premature LH surge on hCG day. A larger scale study will be required to reveal the effectiveness of earlier ovum retrieval with premature LH surge.

• Journal of dental hygiene science
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• v.17 no.6
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• pp.487-494
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• 2017

There is little evidence on the effects of environmental tobacco smoke (ETS) on prevalence of periodontal disease. The aims of this study were to explore the trends of prevalence of periodontal disease and types of exposure to smoke, including ETS according to the survey year, identify factors affecting periodontal disease, and compare the effect size of periodontal disease between active smokers and secondhand smokers. Data on 11,643 individuals were obtained from the fourth and fifth Korean National Health and Nutritional Examination Surveys. Information on exposure to ETS at home and work was self-reported. Severity of periodontal disease was evaluated using the community periodontal index. A multivariate logistic regression analysis was performed to model periodontal disease using types of smoking and the survey year. Overall, the prevalence of periodontal disease was 26.0% (n=3,029) and about 9% of the study population were secondhand smokers. The prevalence of periodontal disease among smokers was significantly increased according to smoking types by year. Active smokers showed a statistically significant adjusted odds ratio (aOR) for having periodontal disease except in the year 2007, whereas secondhand smokers had significant associations only in 2010 (aOR, 1.68; 95% confidence interval, 1.05 to 2.70) compared to non-smokers. For secondhand smokers, the statistical relationship of predicting periodontal disease was weaker than that of active smokers. However, ETS should separately be considered as an important risk factor for periodontal disease. This study suggested the need for further investigation of the impact of ETS on prevalence of periodontal disease using in-depth research designs and objective measurements for assessing periodontal disease and ETS.

• Journal of Chest Surgery
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• v.36 no.5
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• pp.348-355
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• 2003

Background: The prognostic significance of lymph node micrometastasis in non-small cell lung cancer remains controversial. We therefore investigated the clinicopathologic factors related to lymph node micrometastsis and evaluated the clinical relevance of micrometastasis with regard to recurrence. Material and Method: Five hundred six lymph nodes were obtained from 41 patients with stage 1 non-small ceil lung cancer who underwent curative resection between 1994 and 1998. Immunohistochemical staining using anti-cytokeratin Ab was used to detect micrometastasis in these lymph nodes. Result: Micrometastatic tumor cells were identified in pN0 lymph nodes in 14 (34.1%) of 41 patients. The presence of lymph node micrometastasis was not related to any clinicopathoiogic factor (p) 0.05). The recurrence rate was higher in patients with micrometastasis (57.1%) than in those without (37.0%), but the difference was not significant (p=0.22). Patients with micrometastasis had a lower 5-year recurrence-free survival rate (48.2%) than those without micrometastasis (64.1%), with a borderline significance (p=0.11), The S-year recurrence-free survival rate (25.0%) in the patients with 2 or more micrometastatic lymph nodes was significantly lower than that in the patients with no or single micrometastasis (p=0.02). In multivariate analysis, multiple lymph node micromestasis us was a significant independent predictor of recurrence (p=0.028, Risk ratio=3.568). Conclusion: Immunehistochemical anti-cytokeratin staining was a rapid, sensitive, and easy way of detecting lymph node micrometastasis. The presence of lymph node micrometastasis was not significantly associated with the recurrence, but had a tendency toward a poor prognosis in stage 1 non-small cell lung cancer. Especially, the presence of multiple micrometastatic lymph nodes was a significant and independent predictor of recurrence.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.536-542
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• 2007

Behcet's disease (BD) is a chronic inflammatory disorder, involving several organs. Inflammation in the disease is thought to be mediated by cytokines derived from T-helper type 1 (Th1) lymphocytes. Although the exact pathogenesis for BD is not completely understood, it has been suggested that the disease is triggered in genetically susceptible individuals by environmental factors, such as microbial agents. It is noted that multiple genes, including MHC (major histocompatibility complex) and non-MHC genes, are implicated in the pathogenesis of BD. This study tries to determine whether HLA-B51, IL-18, SLC11A1 and TNF-α polymorphisms are associated with susceptibility to Behcet's disease in Koreans. As a results, HLA-B51 was a genetic factor with the strongest association with BD. But it is still uncertain whether this HLA molecule is directly involved in the pathogenesis of BD. Although the IL-18 gene polymorphisms were not associated with a susceptibility to BD in the Korean population, the patients carrying the GG genotype at position 137 had a higher risk of developing the ocular lesions. This study suggests that the allele 3 and the genotype allele 3 / allele 3 of 5'-promoter (GT)n polymorphism in the SLC11A1 gene may have a protective effect for the development of BD in the Korean population. There were no evidences for genetic association conferred by the TNF-α gene with respect to susceptibility to BD.

• Journal of Life Science
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• v.25 no.3
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• pp.276-284
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• 2015

This study was designed to investigate the effect of garlic shoot extract administration on serum and liver tissue lipid levels in hyperlipidemic rats. The rats were fed a 45% high-fat diet to induce hyperlipidemia. They were then administered garlic shoot extract (50%) and ethanol extract (75%) at 200 mg/kg B.W./day (GSA-1, GSB-1) and 400 mg/kg B.W./day (GSA-2, GSB-2) for 5 weeks. The total lipid and triglyceride contents in serum were lowest in the GSB-2 group, and the total cholesterol content was significantly lower in the GSA-2 and GSB-2 groups than in the control group. The high density lipoprotein (HDL)-cholesterol content of the GSB-2 group was similar to that of the normal group. The low density lipoprotein (LDL) and very low density lipoprotein (VLDL)-cholesterol contents were significantly lower in the GSB-1 and GSB-2 group than in the control group. atherogenic index (AI) and cardiac risk factor (CRF) were lowest in the GSB-2 group (0.58 and 1.57, respectively). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) activities were significantly higher in the control group than in the normal group, and the levels of AST, ALT, and ALP were significantly lower in the GSA-2 and GSB-2 groups than in the control group. The total lipid content in liver tissue was significantly lower in all the experimental groups compared to that of the control group, but it was not significantly different among the experimental groups. The total cholesterol and triglyceride content in liver tissue was lowest in the GSB-2 group. Antioxidant activity in serum and liver tissue was highest in the GSB-2 group (40.16% and 47.41%, respectively).The thiobarbituric acid reactive substance (TBARS) content in serum and liver tissue was lowest in the GSB-2 group, with the significant difference. Our results suggest that garlic shoot extracts may improve lipid metabolism in serum and liver tissue and potentially reduce hyperlipidemia.

• Journal of Life Science
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• v.20 no.3
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• pp.396-402
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• 2010

This study was designed to investigate the effects of 4 kinds of plant water extract mixture and garlic extract (PMC) administration on serum lipid metabolism in hypercholestrolemic rats. The normal group was administered a cholesterol free diet, the control group a 1% cholesterol diet, and each experimental group was given a diet of 1% cholesterol, 1% plant mixture and 0.3, 0.5, 0.7% garlic extract (PMC-I, PMC-II, PMC-III), respectively. Each diet was administered orally to SD-male rats for 4 weeks. Total cholesterol content decreased by about 20% with administration of PMC. Triglyceride content also decreased from 9.3 to 15.0% compared to the control group, and phospholipid was similar to triglyceride. There was no significant difference in HDL-cholesterol content between the control and experimental groups. LDL-cholesterol content of the normal group was 9.4 times lower than the control group and its content was significantly lower in the PMC-II ($68.45{\pm}12.83\;mg/dl$) and PMC-III ($66.35{\pm}5.18\;mg/dl$) groups than the PMC-I group. VLDL-cholesterol content of the PMC-II and III groups were similar to the normal group. Atherogenic index (AI) and cardiac risk factor (CRF) were significantly lower in the PMC group. Blood glucose content was the lowest in the PMC-II ($189.37{\pm}12.02\;mg/dl$) group among all groups tested. Total protein content was $9.56{\pm}0.87{\sim}10.05{\pm}2.69\;mg/dl$ in the PMC-I~III groups and was significantly higher than the normal group. CPT activity did not show a significant difference among the experimental groups, while COT activity was effective only in the PMC-I group. Serum TBARS content in the PMC-III group was lower than in the normal group. Serum antioxidant activity by DPPH radical scavenging was $83.75{\pm}2.32%$ in the PMC-III group, which was significantly higher than the control group.

• Journal of Life Science
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• v.23 no.3
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• pp.432-442
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• 2013

In this study, we examined the biological activity and synergistic effects of an extract powder of 1% and 3%, each fresh (FGP) and black garlic (BGP) in streptozotocin-induced diabetic rats. Blood glucose content was significantly lower in FGP and BGP groups than control group. Glycosylated Hb was significantly higher in streptozotocin induced diabetic control group than normal group, but significantly lower in FGP and BGP groups. Total cholesterol content of the FGP and BGP groups were lower than control group, but not shown the significant difference between garlic fed groups. HDL-cholesterol concentrations of the FGP and BGP fed groups were significantly higher than control group, except of 1% BGP group. LDL and VLDL-cholesterol contents were significantly lower in 3% FGP group, and the same tendency atherogenic index and cardiac risk factor. GOT, GPT, and ${\gamma}$-GTP activity of serum were lower in FGP and BGP fed groups than control group. Glycogen contents in liver significantly higher than control group, and has not significantly difference between normal group. TBARS content was no significantly difference in the liver and serum, but in the kidney, 3% FPG and BGP fed groups were significantly lower than other experimental group. DPPH radical scavenging activity of liver has not significant difference among experimental groups, but activity was higher garlic extract powder fed groups in serum and kidney. These results indicate that dietary supplements of fresh and black garlic extract powder was contributed to lower of blood glucose, loss prevention of glycogen in liver and improve of lipid metabolism.

• Journal of Korean Society of societal Security
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• v.4 no.2
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• pp.73-78
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• 2011

In order to resolve the problem of change in global climate which is worsening as days go by and to preemptively cope with strengthened restriction on carbon emission, the government enacted 'Framework Act on Low Carbon Green Growth' in 2010 and selected green technology and green industry as new national growth engines. For this reason, the necessity to use the un-utilized waste heat across the whole industrial system has become an issue, and studies on and applications of recycling in the agricultural and fishery fields such as cultivation of tropical crops and flatfishes by utilizing the waste heat and thermal effluent generated by large industrial complexes including power plants are being actively carried out. In this study, we looked into the domestic and overseas examples of having utilized waste heat abandoned in the form of power plant thermal effluent, and carried out economic efficiency evaluation of sturgeon aquaculture utilizing thermal effluent of Yeongwol LNG Combined Cycle Power Plant in Gangwon-do. In this analysis, we analyzed the economic efficiency of a model business plan divided into three steps, starting from a small scale in order to minimize the investment risk and financial burden, which is then gradually expanded. The business operation period was assumed to be 10 years (2012~2021), and the NVP (Net Present Value) and economic efficiency (B/C) for the operation period (10 years) were estimated for different loan size by dividing the size of external loan by stage into 80% and 40% based on the basic statistics secured through a site survey. Through the result of analysis, we can see that reducing the size of the external loan is an important factor in securing greater economic efficiency as, while the B/C is 1.79 in the case the external loan is 80% of the total investment, it is presumed to be improved to 1.81 when the loan is 40%. As the findings of this study showed that the economic efficiency of sturgeon aquaculture utilizing thermal effluent of power plant can be secured, it is presumed that regional development project items with high added value can be derived though this, and, in addition, this study will greatly contribute to reinforcement of the capability of local governments to cope with climate change.