• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.669-673
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• 2008

For the development of a biological control method against B. cereus in cheonggukjang, 20 Bacillus spp. were isolated from the naturally fermented baektae and heuktae cheonggukjang, identified by using 16S rDNA sequences. Among the isolated strains, Bacillus sp. SC-8 was selected using the B. cereus lawn cell assay as an antagonistic microorganism against B. cereus. The culture medium of Bacillus sp. SC-8 after 24 hr of incubation at $37^{\circ}C$ also evidenced a high level of antagonistic activity. In cheonggukjang fermented with the mixed culture of Bacillus sp. SC-8 and B. cereus, antagonistic effect against B. cereus was maintained during the fermentation of cheonggukjang, while its effect was reduced during storage at $4^{\circ}C$ due to the decrement of cell population of Bacillus sp. SC-8. In Bacillus sp. SC-15, which was utilized a control, antagonistic activity against B. cereus was not demonstrated on the lawn cell plate assay and culture medium, but its effects were detected in cheonggukjang. Therefore, the production of antagonistic substances of Bacillus spp. depends on the fermentative environment.

• Korean Journal of Head & Neck Oncology
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• v.21 no.2
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• pp.146-150
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• 2005

Background and Objectives: When the pleomorphic adenoma(PA) recures, the tumor tends to become a multinodular mass that infiltrates into the normal tissue which is not a common condition for a benign tumor. This manifestation is probably due to the difference in cell biology of the recurrent tumor compared to that of the primary PA. The aim of this study is to assay the immunhistochemical characteristics of the recurrent PA compared to the primary PA and to evaluate whether this property can be used for developing a method that can select the patients who have higher risk to recur. Materials and Methods: Thirteen patients were enrolled in the primary PA group and 15 patients who had a recurrent PA were enrolled in the recurrent PA group. To evaluate the cell biology of the tumor, immunohistochemical stainings of Ki-67, bcl-2 and p53 were performed. Results: There was no difference in the expression of Ki-67 (p=0.117, p=.208) and p53 (p=.430, p=.328). The extent stained by bcl-2 was significantly larger in the recurrent PA group (p=.033, p=.014). The expression of bcl-2 did not increase while time passed. Conclusion: The high expression of bcl-2 seems to be a property of the recurrent PA group which can be found even during first operation before recurrence. By this immunhistochemical characteristic, we would be able to sort out the patients who have higher risk to recur.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.542-547
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• 2010

n-Paraffin and saturated fatty acid methyl esters in the diesel and bio-diesel fuel crystallize at low temperature. Many articles have addressed various solutions for the low temperature crystallization problem and one of them is the use of methacrylate copolymers. In this work, we synthesized a series of copolymers in the reaction condition of 70 : 30 molar ratio of lauryl methacrylate (LMA) (or stearyl methacrylate (SMA)) and alkyl methacrylates. The structures of the copolymers were characterized by $^1H$-NMR and FT-IR spectroscopy, and the molecular weight of copolymers were obtained from Gel Permeation Chromatography (GPC) method. The concentrations of additives were 500~1000 ppm and 1000~10000 ppm in diesel fuels and bio-diesel fuel (BD5 and BD20), respectively. The addition of copolymers changes the many properties of fuel such as the pour point (PP), cloud point (CP) and cold filtering plugging point (CFPP). For example, the low temperature properties of the copolymers containing SMA ($PSMAmR_2n$) were excellently improved about 15, 7, and $10^{\circ}C$ for PP, CP and CFPP, respectively.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.368-372
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• 2009

The viability of Staphylococcus aureus, a significant cause of food poisoning in Korea, on TSA plates was determined after sublethal heating treatments and NaCl treatments. In addition, recovery levels of sublethally injured cells on TSA plates containing different concentrations of NaCl (TSAS) were investigated. The viability decreased significantly with increasing degree of sublethal heating treatments, but increases in NaCl treatment concentrations from 0 to 6% had little effect on the viability. After being sublethally treated at $55^{\circ}C$ for 30 min, bacterial populations were reduced by 7.91, 7.97 and 7.99 log CFU/mL on 2, 4 and 6% TSAS, respectively. After being sublethally treated at 60oC for 30 min, bacterial populations were reduced by 6.46, 6.47 and 6.48 log CFU/mL on 2, 4 and 6% TSAS, respectively. Decimal reduction times (D-value) decreased with increasing NaCl treatment concentrations after sublethal heating at 55 and $60^{\circ}C$. These data imply that the S. aureus cells sublethally injured by insufficient heating processes had a lower recovery rate with increasing NaCl concentrations in the recovery media.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.7
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• pp.658-668
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• 2006

The objective of this study was to develop a technique for the cultivar discrimination using SSR markers in soybean. A total of 91 soybean cultivars developed from 1913 to 2002 in Korea were evaluated by five polymorphic SSR markers (Sat_043, Sat_036, Sat_022, Sat_088 and Satt045). Five SSR markers generated a total of 64 alleles and the number of alleles for each SSR marker ranged from 10 to 15 with average of 12.8. Polymorphic information contents (PIC) by five markers of 91 cultivars were ranged from 0.790 to 0.905 with average of 0.857. A total of 82 cultivars (90%) among 91 soybean cultivars could be individually discriminated by combination of five SSR markers through five step analysis. A cultivar, Buseok, by Sat_043 at the first step, 34 cultivars including Hojangkong by Sat_036 at the second step, 29 cultivars including Dankyeongkong by Sat_022 at the third step, 12 cultivars including Sinpaldalkong 2 by Sat_088 at the fourth step, and 6 cultivars including Saebyeolkong by Satt045 at the fifth step were discriminated. Soybean cultivars which were not discriminated by SSR markers could be discriminated by morphological characteristics.

• Journal of Preventive Medicine and Public Health
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• v.40 no.6
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• pp.467-474
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• 2007

Objectives : Gastric cancer is the most common incident cancer in Korea. Although Helicobacter pylori infection is the most important risk factor for the development of gastric cancer, cigarette smoking has also been suggested to play an important role in the development of gastric cancer. The objective of this study is to evaluate the relationship between cigarette smoking and gastric cancer risk in a Korean population. Methods : The study population consisted of 13,785 subjects who had been enrolled in the Korean Multi-Center Career Cohort between 1993 and 2002. As of December 2002, 139 incident gastric cancer cases were ascertained through the Korea Central Cancer Registry and the National Death Certificate Database. Relative risks (RR) and 95% confidence intervals (CI) for gastric cancer were estimated using Cox#s proportional hazard model adjusted for age, education, alcohol drinking status and history of gastritis or ulcer. Results : Significant dose-response relationships were observed between the duration of smoking and the risk of gastric cancer among the male subjects in comparison to non-smokers: men who smoked for 20-39 years had a 2.09-fold (95% CI 1.00-4.38) increase, and those who smoked for more than 40 years had a 3.13-fold (95% CI 1.59-6.17) increase in the risk of gastric cancer ($P_{trend}<0.01$). Conclusions : This study suggests that a longer duration of cigarette smoking may increase the risk of gastric cancer development in a dose-response manner in Korean men. The association between smoking and gastric cancer risk in women should be verified in future studies with a larger number of cases.

• Journal of Preventive Medicine and Public Health
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• v.41 no.3
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• pp.181-185
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• 2008

Objectives : This study was performed to evaluate the reproducibility of a questionnaire concerned with reproductive history and to ascertain which characteristics of the subjects (age, the visit-revisit intervals, education and chronic disease) are associated with good reliability in the Korean Multi-Center Cancer Cohort (KMCC) study. Materials and Methods: A total of 19,688 participants were enrolled between 1993 and 2004. Among them, we selected 386 participants who were aged 40 or more and who re-visited within 8 years after the first visit. Reliability was measured by the percent agreement according to error range for the continuous variables and the percent agreement and kappa statistics for the categorical variables. Results : The pregnancy histories were reliable (kappa=0.67) and the reasons for being menopausal among the postmenopausal women were also reliable (kappa=0.92). The percent agreement of the breast-feeding history was high (96.1%), although the kappa statistic was low. For the continuous variables, when the error range of one variable was considered to be reliable, the percent agreement of the age at menarche and the age at the first full term pregnancy was good (69.4% and 83.6%), whereas that of the age at menopause was low (51.5%). The factors associated with high reliability were a younger age, the presence of chronic disease and a short visit-revisit time interval. Conclusions : The agreements for parity, the reasons for menopause, and the breastfeeding history in the reproductive history questionnaire used in the KMCC were relatively good. The questionnaire for the menarche age and the menopausal age might have lower reliability due to the difference between Korean age and American age. To obtain reliable information, more attention should be given to the items in questionnaire-based surveys, and especially for surveying old-aged women.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.290-295
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• 2010

Gamigunggui-tang (GMGGT) is one of the important prescriptions that has been used in oriental medicine. We investigated the inhibitory effect of an oral administration of hot water extract of GMGGT on the development of atopic dermatitis (AD) by using Balb/c mice. The induction of atopic dermatitis-like lesion was conducted by the removal of the back hairs and topical application of 2,4-Dinitrochlorobenzene (DNCB) on to the back skin repeatedly. GMGGT was orally administered at a different dose (10.0 mg/kg, 50.0 mg/kg). Skin reactions, consisting of increased ear thickness and the presence of ear inflammation, were observed in mice over three weeks. Oral administration of GMGGT significantly suppressed the skin lesions, ear swelling, spleen weight, total serum IgE in a concentration dependent manner, and also inhibited the infiltration of mast cells in the dorsal skin. In the present study, these results suggested that GMGGT extract inhibits inflammatory response atopic dermatitis. Therefore, GMGGT may be effective substances for the management of AD in human.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.272-277
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• 2010

This experimental study was performed to investigate the antitumor effect of Egg white combined-Chalcanthite (InSan 4, IS4) in xenografted nude mice with NCI-H460 human lung cancer cell. We cultured NCI-H460 cell lines and xenografted them on nude mice. These mice were divided into 3 groups; group with dose of 45 mg/kg IS4 orally, group with dose of 90 mg/kg IS4 orally, and the control group. They had been raised and treated for 28 days. We checked their body weight, tumor weight and volume twice a week, and their absolute organ weight, microhistological observation and biochemical blood analysis at the final day by sacrificing them. We also calculated their tumor inhibition rate (IR), mean survival time and percent increase in life span (% ILS). In this study, we observed that all of the IS4 treated mice have tumor regression, dosage-dependently, compared to the control group. Tumor weight and volume of high dose treated mice were smallest. IR increased in IS4 in a dose-dependent manner. Mean survival time and percent increase in life span (% ILS) in high-dose IS4 treatment group were the highest of the three groups. There was no significant difference in biochemical blood analysis, alanine phopsphatase (ALP), Calcium, creatinine (CRE), alanine transferase (ALT), and aspartate transaminase (AST) levels. The urea nitrogen (UN) level results significantly decreased by IS4 45 and 90 mg/kg (IS4 45 mg/kg, IS4 90 mg/kg, p<0.01). IS4 may have potential anti-tumor effect in a solid tumor induced by NCI-H460 without remarkable side effects.

• Journal of the Korean Society of Radiology
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• v.1 no.1
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• pp.11-16
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• 2007

In this study, we have performed contrast-detail analysis for an amorphous selenium(a-Se) based digital X-ray imaging system by using a contrast-detail phantom(CDRAD 2.0) to test its low contrast performance. The X-ray imaging system utilizes an 500-mm-thick a-Se semiconductor X-ray absorber coated over an amorphous silicon(a-Si) TFT(thin-film transistor) detector matrix with a $139mm{\times}139mm$ pixel size and a $46.7cm{\times}46.7cm$ active area. In the measurement of contrast-detail curves we first acquired X-ray images of the CDRAD 2.0 phantom at given test conditions(i.e., 40, 50, 60, 70, 80 kVp, and 16 mA.s), and then evaluated the contrast-detail characteristics of the imaging system from each phantom image by using an image quality factor called the image-quality-figure-inverse(IQFinv). The IQFinv values for the imaging system gradually improved with the photon fluence, indicating the improvement of image visibility: 24.4, 35.3, 39.2, 41.5, and 43.4 at photon fluences of $1.8{\times}105$, $5.9{\times}105$, $11.3{\times}105$, $19.4{\times}105$, and $29.4{\times}105$ photons/$mm^2$, respectively.