• Genomics & Informatics
• /
• v.10 no.3
• /
• pp.184-193
• /
• 2012

Gastric cancer is ranked as the most common cancer in Koreans. A recent molecular biological study about the folate pathway gene revealed the correlation with a couple of cancer types. In the folate pathway, several genes are involved, including methylenetetrahydrofolate reductase (MTHFR), methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR), and methyltetrahydrofolate-homocysteine methyltransferase (MTR). The MTHFR gene has been reported several times for the correlation with gastric cancer risk. However, the association of the MTRR or MTR gene has not been reported to date. In this study, we investigated the association between the single nucleotide polymorphisms (SNPs) of the MTHFR, MTRR, and MTR genes and the risk of gastric cancer in Koreans. To identify the genetic association with gastric cancer, we selected 17 SNPs sites in folate pathway-associated genes of MTHFR, MTR, and MTRR and tested in 1,261 gastric cancer patients and 375 healthy controls. By genotype analysis, estimating odds ratios and 95% confidence intervals (CI), rs1801394 in the MTRR gene showed increased risk for gastric cacner, with statistical significance both in the codominant model (odds ratio [OR], 1.39; 95% CI, 1.04 to 1.85) and dominant model (OR, 1.34; 95% CI, 1.02 to 1.75). Especially, in the obese group (body mass index ${\geq}25kg/m^2$), the codominant (OR, 9.08; 95% CI, 1.01 to 94.59) and recessive model (OR, 3.72; 95% CI, 0.92 to 16.59) showed dramatically increased risk (p < 0.05). In conclusion, rs1801394 in the MTRR gene is associated with gastric cancer risk, and its functional significance need to be validated.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.63 no.4
• /
• pp.55-64
• /
• 2021

The expansion of upland crop cultivation in rice paddy fields is recommended by the Korean government to solve the problem of falling rice price and reduction of rice farmer's income due to oversupply of rice. However, water use efficiency is significantly influenced by the land use change from paddy field to upland. Therefore, this study aimed to evaluate the water budget of soybean grown in using APEX (Agricultural Policy and Environmental eXtender) model. The amount of runoff was measured in a test bed located in Iksan, Jeollabu-do and used to calibrate and validate the simulated runoff by APEX model. From 2019 to 2020, the water budget of soybean grown in uplands were estimated and compared with the one grown in paddy fields. The calibration result of AP EX model for runoff showed that R² (Coefficient of determination) and NSE (Nash-Sutcliffe efficiency) were 0.90 and 0.89, respectively. In addition, the validated results of R² and NSE were 0.81 and 0.62, respectively. The comparative study of each component in water budget showed that the amounts of evapotranspiration and percolation estimated by APEX model were 549.1 mm and 375.8mm, respectively. The direct runoff amount from upland was 390.1 mm, which was less than that from paddy fields. The average amount of irrigation water was 28.7 mm, which was very small compared to the one from paddy fields.

• Korean Journal of Plant Resources
• /
• v.29 no.4
• /
• pp.363-375
• /
• 2016

Potentilla kleiniana is a perennial herb beloning to Rosaceae family. Herein we investigated the effect of light intensity, light quality and chemical elicitor on plant growth and the accumulation of bioactive compounds in P. kleiniana. After 60 days of cultivation under different shading level [0% (200 μmol·m⁻²·s⁻¹), 35% (95 μmol·m⁻²·s⁻¹), 55% (65 μmol·m⁻²·s⁻¹), 75% (40 μmol·m⁻²·s⁻¹)] in the greenhouse, chlorophyll and carotenoid content were the highest under 35% treatment, however, plant height, leaf number and biomass were the highest under non-shading. As a result of cultivation among strong light condition as a control, florescence and three mixture light sources [red:white:blue (RWB) = 8:1:1, red:blue (RB) = 8:2, red:green:blue (RGB) = 8:1:1] as treatments in plant growth chamber (25 ± 2℃, 185 ± 3 μmol·m⁻²·s⁻¹), growth, biomass, chlorophyll content low difference between total phenolic compouds and flavonoid content were higher under RWB treatment. DPPH radical elimination ability was the highest under all treatments especially florescence and RGB treatment except control. As a result of treating chemical elicitor [salicylic acid (SA), methyl jasmonate (MeJA)] concentration (0, 50, 100, 200 μM) respectively, plant height, petiole diameter and biomass were higher under non-treatment, MeJA 50 μM. It was investigated that fresh weight and dry weight under MeJA 50 μM treatment were especially a little high. Total phenolic compounds and flavonoid content of SA 50 μM treatment was the highest but DPPH radical elimination ability was significantly the highest under MeJA 200 μM (88.65%) and MeJA 50 μM (87.84%) treatment. Thus, this study suggested that we determined optimal shading and light quality in the greenhouse and plant growth chamber also confirmed bioactive compound content, antioxidant ratio increase according to different chemical elicitation concentration.

• Environmental Analysis Health and Toxicology
• /
• v.21 no.4 s.55
• /
• pp.375-380
• /
• 2006

Endocrine disrupting chemicals (EDC) have been emphasized due to their threats in human health. Waste incinerator emission has been emphasized as a source of EDC including polychlorinateddibenzofurans(PCDD/F) and other carcinogenic polycyclic aromatic hydrocarbons (PAHs). Urinary 1-hydroxypyrene (1-OHP) has been used as an exposure biomarker for the PAHs. On the other hand, etheno-DNA adducts, e.g. 1, $N^6-ethenodeoxyadenosine({\varepsilon}dA)$, has been developed as an useful effective or response biomarker for carcinogenesis. Thus, I investigated association between urinary 1-OHP and ${\varepsilon}dA$ levels due to distance from an incinerator which was built more 10 years ago in the middle of a farm in P city. I designated the EDC-high and low exposed group due to distance from the incinerator, i.e. within 2.5km and $5.0{\sim}7.5km$ from the incinerator, respectively. The study subjects were age and sex-matched males and females (mean age, $61.3{\pm}9.6$ yrs; total 40 persons, male, 10; female, 10 for the each group). Urinary 1-OHP and ${\varepsilon}dA$ were analyzed with HPLC-FD and IP-HPLC-FD, respectively. As results, the distance from the incinerator was not associated with urinary 1-OHP nor ${\varepsilon}dA$ levels (p=0.43 and 0.82, respectively). On the other hand, urinary ${\varepsilon}dA$ levels were significantly higher in the hyperlipidemia group (N=10) than normal group (N=30). In conclusion, urinary 1-OHP nor ${\varepsilon}dA$ levels can not be suggested as an incinerator-related exposure nor effective biomarker. However, not only distance from the incinerator bot also systemic approaches including wind and soil contamination are required to assume exposure levels of incinerator-related EDC.

• Journal of Ecology and Environment
• /
• v.43 no.4
• /
• pp.364-375
• /
• 2019

Background: Ecologists continue to investigate the factors that potentially affect the pattern and magnitude of tree damage during catastrophic windstorms in forests. However, there still is a paucity of research on which trees are more vulnerable to direct damage by winds rather than being knocked down by the fall of another tree. We evaluated this question in a mixed hardwood-softwood forest within the Big Thicket National Preserve (BTNP) of southeast Texas, USA, which was substantially impacted by Hurricane Rita in September 2005. Results: We showed that multiple factors, including tree height, shade-tolerance, height-to-diameter ratio, and neighborhood density (i.e., pre-Rita stem distribution) significantly explained the susceptibility of trees to direct storm damage. We also found that no single factor had pervasive importance over the others and, instead, that all factors were tightly intertwined in a complex way, such that they often complemented each other, and that they contributed simultaneously to the overall susceptibility to and patterns of windstorm damage in the BTNP. Conclusions: Directly damaged trees greatly influence the forest by causing secondary damage to other trees. We propose that directly and indirectly damaged (or susceptible) trees should be considered separately when assessing or predicting the impact of windstorms on a forest ecosystem; to better predict the pathways of community structure reorganization and guide forest management and conservation practices. Forest managers are recommended to adopt a holistic view that considers and combines various components of the forest ecosystem when establishing strategies for mitigating the impact of catastrophic winds.

• Clean Technology
• /
• v.24 no.3
• /
• pp.198-205
• /
• 2018

This study investigated the influence of catalyst preparation on the activity of $Co-CeO_2$ catalyst for $N_2O$ decomposition. $Co-CeO_2$ catalysts were synthesized by co-precipitation and incipient wetness impregnation. In order to estimate the performance of the as prepared catalysts, direct catalytic $N_2O$ decomposition test was carried out under $250{\sim}375^{\circ}C$. As a result, the catalyst prepared by co-precipitation (CoCe-CP) showed an enhanced performance on $N_2O$ decomposition reaction even in the presence of $O_2$ and/or $H_2O$, whereas the impregnation catalyst (CoCe-IM) did not. In order to investigate the difference in catalytic activity, characterization such as XRD, BET, TEM, $H_2-TPR$, $O_2-TPD$, and XPS was conducted. It is confirmed that the particle size and specific surface area were changed depending on the catalyst preparation method and the synthesis process influenced the physical properties of the catalysts. In addition, the improvement in the activity of the catalyst prepared by co-precipitation is due to the enhanced reduction from $Co^{3+}$ to $Co^{2+}$ and the improved oxygen desorption rate. However, it has been confirmed that the surface electron state and binding energy, which are related to $N_2O$ decomposition, do not change depending on the preparation method.

• Environmental and Resource Economics Review
• /
• v.18 no.2
• /
• pp.345-375
• /
• 2009

In this paper we examined the impact of mineral resources industry on the national economy and necessity of a mineral resources cycle technology development. For this purpose, the case study on Gagok polymetallic (zinc-lead-copper) mine, which is being re-developed, was carried out to study an anticipated effects of application of the full cycle technology. As a consequences of the study, if we apply the technology to a polymetallic (zinc-lead-cooper) mine, we can expect 55 billion won worth of import-substitution effect. Moreover, if applied to 10 similar mines, we can expect the 10.4% of import-substitution effect of the total imports annually. Also, national competitiveness in value chain of mineral industry will be promoted through the technological advancement in upper stream and the full cycle technology will render a service to the mineral industry to be the country's new growth engine.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.33 no.2
• /
• pp.23-42
• /
• 2020

Objectives : This study is designed to analyze the outpatients who received medical treatments for ear diseases in ophthalmology & otolaryngology & dermatology clinic of Daejeon Korean Medical Hospital from March, 2013 to February, 2019. Methods : We classified the otology outpatients who received medical treatments in ophthalmology & otolaryngology & dermatology clinic of Daejeon Korean Medical Hospital from March, 2012 to February, 2019 according to gender, year, age, season, anatomical parts, and main diagnosis. The statistical analysis was performed using SPSS 25.0. Results : 1. The number of outpatients with ear diseases were 880; 505 female and 375 male. The number of female patients were approximately 1.7 times higher. 2. The average age of the outpatients with ear diseases were 50.0. The number of middle-aged (40-50s) patients were 439, which is almost half the number(49.9%) of the whole patients. 3. By analyzing the number of patients classified by year, we found out that the number of the outpatients with ear diseases has increased gradually for the past 7 years. 4. In the analysis of the number of patients classified by the anatomical parts of the ear, the inner ear diseases group were the largest, amounting to 79.3% of the whole patients. 5. In the analysis of the number of patients classified by main diagnosis, Tinnitus turns out to be the largest group with 338 patients, followed by sudden sensorineural hearing loss, dizziness, otalgia, Meniere's syndrome, otitis, auditory tube dysfunction, BPPV. 6. No statistical-significant difference were shown in the analysis of the number of patients classified by season. Conclusions : It turns out that patients with ear diseases had increased by the years, and middle aged patients (40-50s) were the largest among the age groups. Most of the patients came for the inner-ear diseases, and tinnitus, sudden sensorineural hearing loss took up the largest proportions.

• Korean Journal of Community Nutrition
• /
• v.25 no.3
• /
• pp.236-245
• /
• 2020

Objectives: Cardiovascular disease is a major cause of death in the elderly in Korea. Increased arterial stiffness is linked to risk of cardiovascular disease and mortality. The purpose of this study was to investigate the relationship between arterial stiffness and physical activity in the elderly. Methods: A total of 209 older adults (110 men and 99 women) participated in this study. Arterial stiffness of subjects such as brachial-ankle pulse wave velocity (baPWV) and ankle brachial pressure index (ABI) was measured using a non-invasive vascular screening device (VP-1000 Plus, Omron, Kyoto, Japan). The interviewed Korean version of the international physical activity questionnaire short form (IPAQ-SF) was used to evaluate subject's physical activity level and classify subjects as active or inactive group based on the time spent doing moderate to vigorous physical activity (MVPA). Results: The mean age of total subjects was 75.3 ± 5.6 years. There was no significant difference in sex distribution between the active group (39.7%) and inactive group (60.3%). The baPWV (1,758.1 ± 375.2 cm/sec) of the active group was significantly lower than that (1,969.7 ± 372.3 cm/sec) of the inactive group (P < 0.05). There was a significant inverse association between time spent in MVPA and baPWV (r = -0.245, P < 0.01). Conclusions: This study suggests that physical activity programs for older adults are needed to prevent arteriosclerosis.

• The korean journal of orthodontics
• /
• v.23 no.3 s.42
• /
• pp.375-389
• /
• 1993

The delivery of optimal orthodontic treatment is greatly influenced by a clinician's ability to predict and control tooth movement achieved by applying known force systems to the dentition. It is important to determine the location of the center of resistance of a tooth or group of teeth to better understand the nature of their displacement characteristics under the various force levels. The purpose of this study was to define the location of the centers of resistance of various units of the upper anterior segment for lingually directed 100gm and 200gm force in a dry human skull. The units investigated were composed of four incisors and six anterior teeth. In addition, the effect of change in force magnitude on the location of the center of resistance of these units was investigated. The laser reflection technique was used to measure the initial displacements of the consolidated teeth under loading. The results were as follows: 1. The instantaneous center of resistance for the four anterior teeth was located vertically between level 4 and level 5-that is, at $37.4\%$ apical to the cementoenamel junction level. 2. The instantaneous center of resistance for the six anterior teeth was located vertically just beneath level 5-that is, at $50.3\%$ apical to the cementoenamel junction level. 3. Increasing force levels had little effect on the location of the center of resistance of a given unit. 4. The location of the instantaneous center of resistance shifted apically as the number of dental units consolidated increased.