• Korean Journal of Soil Science and Fertilizer
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• v.36 no.2
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• pp.92-103
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• 2003

Research and technological advances in the field of remote sensing have greatly enhanced the ability to detect and quantify physical and biological stresses that affect the productivity of agricultural crops. Reflectance in specific visible and near-infrared regions of the electromagnetic spectrum have proved useful in detection of nutrient deficiencies. Especially crop canopy sensors as a ground remote sensing measure the amount of light reflected from nearby surfaces such as leaf tissue or soil and is in contrast to aircraft or satellite platforms that generate photographs or various types of digital images. Multi-spectral vegetation indices derived from crop canopy reflectance in relatively wide wave band can be used to monitor the growth response of plants in relation to environmental factors. The normalized difference vegetation index (NDVI), where NDVI = (NIR-Red)/(NIR+Red), was originally proposed as a means of estimating green biomass. The basis of this relationship is the strong absorption (low reflectance) of red light by chlorophyll and low absorption (high reflectance and transmittance) in the near infrared (NIR) by green leaves. Thereafter many researchers have proposed the other indices for assessing crop vegetation due to confounding soil background effects in the measurement. The green normalized difference vegetation index (GNDVI), where the green band is substituted for the red band in the NDVI equation, was proved to be more useful for assessing canopy variation in green crop biomass related to nitrogen fertility in soils. Consequently ground remote sensing as a non destructive real-time assessment of nitrogen status in plant was thought to be useful tool for site specific crop nitrogen management providing both spatial and temporal information.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3325-3328
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• 2012

Aim: To evaluate the association of glutathione S-transferases gene polymorphisms with the risk of gastric cancer, with reference to smoking and Helicobacter pylori infection. Methods: We conducted a 1:1 matched case-control study with 410 gastric cancer cases and 410 cancer-free controls. Polymorphisms of GSTM1, GSTT1 and GSTP1 were determined using PCR-CTPP. Results: The GSTM1 and GSTT1 null genotypes were significantly associated with the risk of gastric cancer after adjusting for potential confounding factors (OR=1.68, 95% CI=1.32-2.23 for null GSTM1, OR=1.73; 95% CI=1.24-2.13 for null GSTT1). The combination of null GSTM1 and null GSTT1 conferred an elevated risk (OR=2.54, 95% CI=1.55-3.39). However, no association was found for GSTP1 polymorphism The smoking modified the association of GSTM1 and GSTT1 null genotypes with the risk of gastric cancer. Conclusion: GSTM1 and GSTT1 null genotypes are associated with increased risk of gastric cancer, and smoking modifies the association.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5069-5074
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• 2012

Objectives: The purpose of this study was to determine the relationship between methylation status of the Dact1 gene and MTHFR a1298c polymorphic forms in transitional cell carcinoma tissues in a Chinese population. Methods: Polymorphisms of folate metabolism enzyme gene MTHFR were assessed by restrictive fragment length polymorphism (RFLP) methods and PCR-based DNA methylation analysis was used to determine the CpG island methylation status of the Dact1 gene. Associations between the methylation status of the Dact1 gene and clinical characteristics, as well as MTHFR a1298c polymorphisms, were analyzed. Results: aberrant methylation of the Dact1 gene was found in 68.3% of cancer tissues and 12.4% of normal tissues,. The methylation rate of the Dact1 gene in cancer tissues was significantly higher in patients with lymph node metastasis than in those without lymph node metastasis (46.3% vs. 17.2%, P = 0.018). No association was found between aberrant DNA methylation and selected factors including sex, age, tobacco smoking, alcohol consumption and green tea consumption. After adjusting for potential confounding variables, variant allele of MTHFR a1298c was found to be associated with methylation of the Dact1 gene. Compared with wild type CC, the odds ratio was 4.33 (95% CI: 1.06-10.59) for AC and 4.95 (95% CI: 1.18-12.74) for AA. The N stage in TNM staging and the occurrence of lymph node metastasis were associated with an MTHFR 1298 AA+AC genotype (P<0.05). Conclusion: MTHFR 1298 AC and AA genotypes might help maintain a normal methylation status of the Dact1 gene, aberrant CpG island methylation of which is closely related to the genesis and progression of transitional cell carcinoma.

• Journal of Nutrition and Health
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• v.44 no.5
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• pp.406-415
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• 2011

Recent studies have shown that high consumption of processed meat may be associated with increasing risk of metabolic syndrome, which have been suggested as a predictor of diabetes and cardiovascular disease. However, limited studies have investigated this association in Korean population. The purpose of this study was to investigate the cross-sectional association between processed meat/unprocessed (beef, pork, chicken) intakes and the prevalence of metabolic syndrome. Using data from 2007-2008 Korean National Health and Nutrition Examination Survey (KNHANES), we analyzed data including 5,545 men and women who were aged older than 20 years, and who were free of chronic disease such as hypertension, type 2 diabetes and cardiovascular disease. Subjects who frequently consumed processed meat tended to be younger and more likely to be current smokers. In addition, men were more likely to consume processed meat than women. Although higher processed/unprocessed meat intakes were significantly associated with the lower risk of metabolic syndrome in a crude model, these associations were no longer significant after adjustment for potential confounding factors. For example, comparing subjects in the highest intake quartile of processed meat with the lowest intake group, the multivariate-adjusted odds ratio (OR) of metabolic syndrome was 0.92 (95% CI: 0.58-1.46) for processed meat, 1.09 (95% CI: 0.76-1.56) for beef, 1.10 (95% CI: 0.74-1.62) for pork and 0.75 (95% CI: 0.51-1.12) for chicken. In conclusion, we found no evidence of any adverse effects of frequent processed or unprocessed meat intakes on the prevalence of metabolic syndrome among Korean adults at the exposure levels seen in this study.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10883-10885
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• 2015

Purpose: Neutrophil-to-lymphocyte ratio (NLR) was evaluated as a potential prognostic factor in patients with myelodysplastic syndrome (MDS). Materials and Methods: Between December 2009 and April 2014, 14 female (35%) and 26 male (65%) MDS patients who were followed up in our hematology clinic were included in the study for NLR during diagnosis. Division was into two groups according to the NLR, and the correlation with mortality was evaluated. The prognostic significance of NLR regarding treatment outcome was also evaluated with adjustment for known confounding risk factors. Results: The mortality rate of the patient group was 55%, and median survival was 18 months. There was no significant correlation between mortality and NLR at a median value of 1.8 (p=0.75). Thrombocytopenia was observed to increase mortality (p=0.027), and there was a significant correlation between mortality and pancytopenia (p=0.017). Conclusions: This first study of NLR and mortality did not show any significant correlation. In centres with limited access to genetic evaluation for the presence of pancytopenia and/or thrombocytopenia at the time of diagnosis, a platelet level less than $50{\times}10^9/l$ may be poor prognostic markers in MDS patients.

• Journal of Preventive Medicine and Public Health
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• v.30 no.4 s.59
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• pp.852-869
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• 1997

This study was conducted to develop and evaluate the reliability and the validity of a questionnaire in order to determine the applicability as a screening tool for estimating environmental exposure and health effects related to air pollution. The questionnaire was developed with adopting some items of others such as ISAAC or ATS-DLD. And then we performed test-retest to 89 middle school students and their mothers at interval of three months. Cohen's Kappa values, weighted Kappa values, Spearman's correlation coefficients, and Pearson's correlation coefficients for each item were computed as reliability coefficients. The validity coefficients and validity coefficient bounds were also obtained by simply using these reliability coefficients. As results, Kappa ranged broadly from 0.10 to 0.61 of the items 'diet', $0.52\sim0.79$ of the environmental tobacco smoke, $0.39\sim0.44$ of the functional categories of surrounding environment, and $0.39\sim0.44$ of the using transportation systems; these items were regarded as confounding factors. For items related to health outcomes, Kappa ranged from -0.02 to 0.37 in the respiratory system of past medical history, and from 0.11 to 0.55 in the current health status. But Kappa of the others were over 0.60. In conclusion, if some items can be corrected or modified, the questionnaire developed in this study can be used as a tool for evaluating environmental exposure and health effects associated with air pollution.

• Journal of Preventive Medicine and Public Health
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• v.33 no.2
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• pp.165-173
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• 2000

Objectives : To assess the availability of the glycophorin A (GPA) assay to detect the biological effect of ionizing radiation in workers exposed to low-doses of radiation. Methods : Information on confounding factors, such as age and cigarette smoking was obtained on 144 nuclear power plant workers and 32 hospital workers, by a self-administered questionnaire. Information on physical exposure levels was obtained from the registries of radiation exposure monitoring and control at each facility. The GPA mutant assay was performed using the BR6 method with modification by using a FACScan flow cytometer. Results : As confounders, age and cigarette smoking habits showed increasing trends with GPA variants, but these were of no statistical significance. Hospital workers showed a higher frequency of the GPA variant than nuclear power plant workers in terms of the NO variant. Significant dose-response relationships were obtained from in simple and multiple linear regression models. The slope of the regression equation for nuclear power plant workers was much smaller than that of hospital workers. These findings suggest that there may be apparent dose-rate effects. Conclusion : In population exposed to chronic low-dose radiation, the GPA assay has a potential to be used as an effective biologic marker for assessing the bone marrow cumulative exposure dose.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.1099-1104
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• 2010

Aim of this study was to determine if obesity or abdominal obesity is more prevalent in persons with allergic rhinitis compared with healthy persons and to determine if obesity or abdominal obesity affects severity of rhinitis's symptoms. We studied 44 allergic rhinitic patients and 47 healthy persons. BMI and WHR were measured by the In-body 520. And severity of rhinitis's symptoms were assessed by questionnaires. The prevalence of obesity in allergic rhinitis group(27.3%) was significantly higher than control group(10.6%). And the prevalence of abdominal obesity in allergic rhinitis group(43.2%) was higher than control group(40.4%), but was not statistically significant. Nasal obstruction score of obesity group was higher than control group, but was not statistically significant. And nasal obstruction, Korean Allergic Rhinitis Specific Quality of Life Questionnaire (KARQLQ) score of abdominal obesity group were significantly higher than control group. And when age and sex are corrected, allergic rhinitis and obesity's association was statistically significant. The prevalence of obesity in allergic rhinitis group was significantly higher than control group. Also when age and sex are corrected, allergic rhinitis and obesity's association was statistically significant. And nasal obstruction score was higher in obesity than control group, but was not significant. The other side, nasal obstruction and KARQLQ score in abdominal obesity group was significantly higher than control group. Thus, we thought that fixed various confounding factors and large-scale studies will be needed.

• Journal of Community Nutrition
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• v.6 no.3
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• pp.125-130
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• 2004

The purpose of this study is to investigate the relative influence of diet and physical activity on obesity. The subjects were 155 adults aged 35-52 years from 24 neighborhood committees in 4 urban districts of Beijing (male : 78, female : 77). They were divided into normal weight, overweight and obese groups according to their BMI. The general information of the subjects was collected by interview-administered questionnaire. Dietary intake was obtained by three-day(two weekdays and one weekend day) food weighted method, physical activity was assessed by a validated combination of data obtained from activity monitors, bicycling information and activity records. There were no significant differences of age, gender, height, educational, family economic level, smoking and drinking between different groups. The proportion of flour intake was higher in obese group compared to normal weight and overweight groups, and that of vegetables is lower in obese group. The physical activity (PAL) was not significantly different between two groups of the normal, overweight and obese groups. After the adjustment for confounding factors using logistic regression model, we found that the proportion of flour intake was positively associated with obesity, while the proportion of vegetable intake was inversely associated with obesity. It is concluded that dietary patterns were associated with obesity and diets composed of more vegetables and less staple combined with physical activities could contribute to obesity prevention.

• Korean Journal of Community Nutrition
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• v.16 no.3
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• pp.315-323
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• 2011

There are a few studies that reported the association of sleep duration with calorie intake and energy expenditure. Using cross-sectional data from a population-based prospective study, we evaluated the association of sleep duration with indicators of obesity including body mass index and waist circumference, calorie intake and its proportion of macronutrients, and physical activity. The study subjects were 4,226 male and female adults, who were aged 40 to 69 years and were free of diagnosed cardiovascular disease, diabetes mellitus, and dyslipidemia at baseline. Robust regression analysis was used to analyze associations. The study found that sleep duration is inversely associated with waist circumference, calorie intake, and percent of calories from fat intake and is positively associated with percent of calories from carbohydrate intake and physical activity. The inverse association between sleep duration and waist circumference was stronger among men than among women. The inverse association between sleep duration and calorie intake was stronger among women than among men and such association was also stronger among obese persons than those with a normal body mass index. The positive association between sleep duration and physical activity was strongly demonstrated regardless of sex or obesity. Physical activity is positively associated with sleep duration independent of potential confounding factors including age, sex, income, occupation, marital status, education, smoking status, waist circumference, calorie and macronutrient intake, and alcohol intake.