• Journal of environmental and Sanitary engineering
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• v.19 no.3 s.53
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• pp.13-21
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• 2004

This study was focused on the evaluation of Nanjido landfill site by leachate analysis. Several parameters, for example pH, BOD, $COD_{Mn},\;COD_{Cr}$, SS, TP, $NH_3-N$, Color, were selected as major leachate quality parameters. $BOD/COD_{Cr}$. was used to estimate the biodegradable portion in organic matter. Samples were collected at the leachate storage wells and leachate treatment facility inflow in each quarter of 2003. The results were as follows : 1. Inflow quality of treatment plant in 2003 was analysed as $pH\;7.3\~8.0,\;BOD\;12.4\~30.0mg/L,\;COD_{Mn}\;101.2\~130.3mg/L,\;COD_{Cr}\;122.5\~238.0mg/L,\;SS\;16.1\~115.3mg/L$, $T-P\;0.27\~0.80mg/L,\;NH_3-N\;208.0\~~354.0mg/L$, Color $110.3\~129.0$ unit. 2. $BOD/COD_{Cr}$ of inflow ranged between $0.07\~0.16$ indicating that the landfill had the properties of old-fill and organic portion in leachate was mostly persistent organic matter. 3. Though concentrations of BOD, COD, $NH_3-N$, Color in leachate storage wells were mostly higher in first landfill than in second landfill, $BOD/COD_{Cr}$ ranging from 0.03 to 0.20, showed reversely. 4. Correlation coefficient$(R^2)$ between color and other parameters related to organic matter showed mostly above 0.7 and especially highest value with $COD_{Mn}$ of 0.7985.

• Journal of Environmental Health Sciences
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• v.38 no.1
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• pp.57-65
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• 2012

Objectives: For our survey of the incidence of norovirus infections and the genogroup distribution of norovirus in Seoul, Republic of Korea, we evaluated through regular surveillance the prevalence of norovirus infections in patients with acute gastroenteritis occurring in Seoul from January 2007 to July 2011. Methods: For norovirus detection, we conducted epidemiological analyses on the basis of the junction of ORF1 and ORF2 (approximately 314 bp). 11,202 fecal specimens were collected from patients in Seoul with acute gastroenteritis between January 2007 and July 2011 and then tested for the presence of NoV via reverse transcription (RT) - polymerase chain reaction (PCR). Results: 16.6% (1,861/11,202) of the fecal specimens were determined to be positive for noroviruses. The incidences of norovirus infection in Seoul in the case of acute gastroenteritis with regular surveillance were 28.0% in 2007, 14.6% in 2008, 9.1% in 2009, 14.1% in 2010, and 12.9% in 2011, which shows that noroviruses constituted a major causative agent of acute gastroenteritis. Also, the incidence of noroviral infection in patients with acute gastroenteritis increased after the large-scale new influenza in 2009. Conclusions: The genetic characteristics of norovirus and the epidemiologic patterns of a viral pathogen in acute gastroenteritis patients may provide potentially effective data for epidemiological studies in Seoul, Korea.

• Tuberculosis and Respiratory Diseases
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• v.80 no.3
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• pp.265-269
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• 2017

Background: The first line of anti-tuberculosis (TB) drugs are the most effective standard of drugs for TB. However, the use of these drugs is associated with hepatotoxicity. Silymarin has protective effects against hepatotoxicity of anti-TB drugs in animal models. This study aims to investigate the protective effect of silymarin on hepatotoxicity caused by anti-TB drugs. Methods: This is a prospective, randomized, double-blind and placebo-controlled study. Patients were eligible if they were 20 years of age or order and started the first-line anti-tuberculosis drugs. Eligible patients were randomized for receiving silymarin or a placebo for the first 4 weeks. The primary outcome was the proportion of patients who showed elevated serum liver enzymes more than 3 times the upper normal limit (UNL) or total bilirubin (TBil) > $2{\times}UNL$ within the first 8 weeks of anti-TB treatment. Results: We enrolled a total of 121 patients who silymarin or a placebo to start their anti-TB treatment, for the first 8 weeks. The proportions of elevated serum liver enzymes more than 3 times of UNL at week 2, week 4, and week 8 did not show any significant difference between the silymarin and placebo groups, at 0% versus 3.6% (p>0.999); 4.4% versus 3.6% (p>0.999); and 8.7% versus 10.8% (p=0.630), respectively. However, patients with TBil >$2{\times}UNL$ at week 8 were significantly low in the silymarin group (0% versus 8.7%, p=0.043). Conclusion: Our findings did not show silymarin had any significant preventive effect on the hepatotoxicity of anti-TB drugs.

• Journal of Environmental Health Sciences
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• v.39 no.2
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• pp.178-186
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• 2013

Objective: Human enteroviruses (HEVs) are a common causative agent of gastrointestinal or respiratory infections. In this study, to examine the genotypic diversity and characteristics of HEVs associated with patients in Seoul, we collected and analyzed stool and throat swab samples taken from patients with acute gastroenteritis or a common cold from 2011 to 2012. We researched the difference in genetic characteristics of HEVs from gastroenteritis and respiratory patients. Methods: For genetic analysis, we amplified the 5'-noncoding region and partial VP1 region of HEVs by RT-PCR. The genotypes of HEVs were further identified based on nucleotide sequences of the VP1 region. Results: The majority of the HEV infections in Seoul occurred from June to August. The molecular characteristic assay showed that although the majority of HEVs can be propagated by a fecal-oral route, Coxsackievirus A2 (n=13, 19.4%), A4 (n=8, 11.9%), and A5 (n=4, 6.0%) can be preferentially transmitted by a respiratory route. Conclusions: This Enterovirus surveillance system plays an important role in preparing for a severe outbreak. The genotypic characteristics of HEV may provide potentially useful data needed for epidemiological studies.

• Korean Journal of Veterinary Service
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• v.37 no.3
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• pp.197-202
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• 2014

Dirofilaria immitis infection is one of the most important parasitic diseases in dogs and public health. It often elicits nodules in the pulmonary parenchyma and in the subcutaneous tissues of human. In this study, we investigated the prevalence of D. immitis infection among 754 dogs in Seoul area from April to December 2012. The infection rate of 754 dogs was 9.8% (74/754) by the antigen test (canine SNAP 4Dx). The infection rates of D. immitis in dogs at the age of < 2, 2~4, 5~7, 8~10, and > 10 years were 3.7% (7/189), 12.9% (30/233), 15.0% (19/127), 9.8% (18/184), and 0% (0/21), respectively. The infection rates in the female and male dogs were 9.7% (33/340) and 9.9% (41/414), respectively. The regional infection rates in northern and southern Han river region of Seoul were 10.7% (44/410) and 8.7% (30/344), respectively. In order to confirm D. immitis infection, we performed PCR on serum samples of 74 dogs which tested positive for D. immitis antigen by the antigen test and we detected a specific gene ITS-2 in 59 serum samples. In conclusion, this study suggests that treatment and preventive care on the D. immitis infection should be considered in dogs of Seoul area.

• Korean Journal of Veterinary Service
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• v.37 no.3
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• pp.191-196
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• 2014

This study was conducted to compare the contents of preservatives and general composition on four different types of cheese to provide useful data and information to the consumer. We analyzed preservatives (sorbic acid, benzoic acid, dehydroacetic acid, methyl p-hydroxy benzoate, ethyl p-hydroxy benzoate, propionic acid) and general composition (moisture, protein, fat) from total 102 cheeses which are 46 sliced cheeses, 22 string cheeses, 20 cream cheeses and 14 pizza cheeses. Preservatives were detected from total 14 samples, which are suitable for the authorized limits in Korea. Sorbic acid was detected from 13 samples (197.3~1,736.1 mg/kg) and propionic acid was detected from 1 sample (362.7 mg/kg). Considering from each type of cheese, cream cheese showed the high detection rate (60%); 12 samples of cream cheese contained sorbic acid. The moisture, protein and fat contents of cheeses were in the ranges of 44.3~56.8%, 7.2~24.6% and 19.6~26.8%. Cream cheese had the highest level of moisture (56.8%) and fat (26.8%), but protein level is very low (7.2%).

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.135-139
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• 2008

Fecal specimens from acute gastroenteritis in Seoul from 2004 to 2007 were collected and then tested for the presence of norovirus by RT-PCR. 258 noroviruses were subjected to be futher characterized to sequencing analysis. The sequencing analysis showed that thirteen genotypes were detected (GII.1, GII.2, GII.3, GII.4, GII.5, GII.6, GII.8, GII.10, GII.l2, GII.13, GII.l5, GII.l6, GII.l7) and predominant genotype was GII.4 (76.7%) in the cases of norovirus detected sporadic acute gastroenteritis in Seoul. By this molecular investigation, genotypic distribution associated with norovirus infections will be used for control and prevention of norovirus related diseases.

• Journal of Korean Society on Water Environment
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• v.32 no.5
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• pp.410-418
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• 2016

This study was conducted to improve the analysis method used for N-nitrosamines and to investigate the occurrences of N-nitrosamines in tributaries of the Han-river, intake stations, water treatment plants and tap water used within the city of Seoul. The samples were pretreated through a solid phase extraction and analyzed using a gas chromatography tandem mass spectrometer (GC-MS/MS). The GC-MS/MS in CI mode was compared with the GC-MS/MS in EI mode by the method detection limits (MDLs). MDLs by GC-CI/MS/MS and GC-EI/MS/MS were 0.2 ~ 1.1 ng/L and 0.2 ~ 1.4 ng/L, respectively. Samples were collected from ten tributaries of the Han-river (T1 ~ T10), six intake stations (I1 ~ I6), six water treatment plants (P1 ~ P6) and 25 taps in Seoul city. The maximum levels of N-nitrosodimethylamine (NDMA) were 0.013 μg/L, 0.008 μg/L, 0.006 μg/L and 0.002 μg/L in tributary water, raw water, finished water and tap water samples, respectively. Detected levels were much lower than 0.1 μg/L corresponding to the guideline value of WHO.

• Preventive Nutrition and Food Science
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• v.18 no.4
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• pp.263-268
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• 2013

In this study, the quick HPLC-MS/MS method for the simultaneous separation of 2-acetyl-4(5)-tetrahydroxybuthylimidazole (THI) and 4-(5)-methylimidazole (4-MI) in alkaline medium was used for caramel color and processed foods in Korea. After a simple sample pretreatment, 51 4-MI-labeled samples were positive for 4-MI and 2 also contained THI. The concentration of 4-MI was 260.5~24, $499.3{\mu}g/kg$ in caramel color, less than $LOD{\sim}1,712.5{\mu}g/kg$ in sauce, 1,242.3, $5,972.2{\mu}g/kg$ in balsamic vinegar, $2,118.3{\sim}5,802.4{\mu}g/kg$ in complex seasoning, $82.7{\sim}5,110.6{\mu}g/kg$ in curry, and $29.9{\sim}464.4{\mu}g/kg$ in soft drinks. The recovery rate of 4-MI was 97.1~111.0% in sauce and 81.9~110.0% in powder and that of THI was 83.6{\sim}106.4% in sauce and 61.2{\sim}99.4% in powder. Our results concluded a safe amount of 4-MI and THI compared to the limit of Korea additive code but the processed foods do not have a limit of caramel color and 4-MI in Korea. Therefore, research and monitoring of 4-MI and THI is needed for processed foods in Korea.

• Restorative Dentistry and Endodontics
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• v.43 no.4
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• pp.42.1-42.7
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• 2018

Objectives: The purpose of this study was to investigate the C-shaped root canal anatomy of mandibular second molars in a Korean population. Materials and Methods: A total of 542 teeth were evaluated using cone-beam computed tomography (CBCT). The canal shapes were classified according to a modified version of Melton's method at the level where the pulp chamber floor became discernible. Results: Of the 542 mandibular second molars, 215 (39.8%) had C-shaped canals, 330 (53%) had 3 canals, 17 (3.3%) had 2 canals, 12 (2.2%) had 4 canals, and 8 (1.7%) had 1 canal. The prevalence of C-shaped canals was 47.8% in females and 28.4% in males. Seventy-seven percent of the C-shaped canals showed a bilateral appearance. The prevalence of C-shaped canals showed no difference according to age or tooth position. Most teeth with a C-shaped canal system presented Melton's type II (45.6%) and type III (32.1%) configurations. Conclusions: There was a high prevalence of C-shaped canals in the mandibular second molars of the Korean population studied. CBCT is expected to be useful for endodontic diagnosis and treatment planning of mandibular second molars.