• Nuclear Medicine and Molecular Imaging
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• 제41권5호
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• pp.364-372
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• 2007

목적 : 여러 종양영상용 방사성의약품이 암환자에서 치료후 반응을 보는 데 사용되고 있다. 이 연구에서는 paclitaxel 노출 시간에 따른 여러 종양영상용 방사성의약품의 유방암세포 섭취양상을 paclitaxel 노출 48시간까지 생존종양세포 수와 비교하여 알아보았다. 대상 및 방법 : F-18-fluorodeoxyglucose, C-11-methionine, Tl-201, Tc-99m-MIBI, Tc-99m-tetrofosmin의 5가지 종양영상용 방사성의약품의 MCF-7 유방암세포에서의 세포섭취를 알아보았다. DMSO 노출 대조군, 다양한 paclitaxel 노출시간을 가지는 5가지의 실험군(노출시간 2시간, 6시간, 12시간, 24시간, 48시간)의 총 6가지 조건에서 종양영상용 방사성의약품을 60분간 섭취시킨 뒤 섭취율을 구하였다. Paclitaxel은 10 nM과 100 nM의 2가지 농도를 사용하였다. 결과 : 10 nM의 paclitaxel은 노출 48시간까지 MCF-7 세포의 살아 있는 세포의 비율을 약 75% 정도로 감소시켰지만, 종양세포의 5가지 종양영상용 방사성의약품 섭취는 대조군과 비교시 유의하게 감소하지 않았다. 100 nM의 paclitaxel은 노출 48시간까지 MCF-7 세포의 살아 있는 세포의 비율을 약 55% 정도로 감소시켰지만, 종양세포의 5가지 종양영상용 방사성의약품 섭취는 대조군과 비교시 유의하게 증가하였다. 결론 : MCF-7 유방암세포주에서 종양영상용 방사성의약품인 F-18-FDG, C-11-methionine, Tl-201, Tc-99m-MIBI, Tc-99m-tetrofosmin의 섭취율은 paclitaxel 투여 후 48시간까지 생존 종양세포 수의 감소를 반영하지 못한다.

• 한국식품위생안전성학회지
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• 제37권3호
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• pp.173-180
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• 2022

오징어의 품질을 평가하기 위한 여러 항목 들이 있으나 현장에서 소비자 및 유통업자들의 경우 주관적인 관능평가에 의존하고 있으며 소비자의 어류 구매의사 결정에 부패취가 직접적인 영향을 미칠 수 있다. 따라서 관능적 평가를 입증 할 수 있는 과학적인 품질인자를 제시하고자 하였으며, 온도와 저장시간에 따른 상호관계를 분석하였다. 과학적 품질인자로는 TVC, Pseudomonas spp., pH, VBN 으로 선정하였으며 세 가지 온도 조건에서 보관하였다. 이취발생검지시점은 R-index를 이용해 측정하고 kinetic 모델링을 진행하였다. 모델링 결과 활성화 에너지는 이취발생검지 시간이 51.210 kJ/mol, TVC는 42.888 kJ/mol, Pseudomonas spp.는 50.283 kJ/mol, VBN은 72.594 kJ/mol, pH는 41.990kJ/mol 으로 나타났다. Pseudomonas spp., TVC, pH, VBN 순으로 이취발생검지 시간의 활성화 에너지에 근사하였으며, 특히 Pseudomonas spp.는 이취발생검지 시간의 활성화 에너지와 가장 유사하였다. 따라서 오징어의 이취발생 indicator는 이취발생시간과 가장 유사한 양상을 나타내는 Pseudomonas spp.로 판단 할 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.75-80
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• 1997

An ethanolic fermentation process was developed for preparing Doenjang with high ethanol. Higher and efficient viable cell production of salt-tolerant ethanolic yeast is a prerequisite for the successful commercial-scale process of ethanol production during Doenjang fermentation. Culture conditions of salt-tolerant yeast, S. cerevisiae KFCC 10823, was studied in terms of the effect of several environmental and nutritional factors. Viable cell numbers were the highest in a medium containing the following components per liter of water: soysauce, 300ml; dextrose, 50 g; beef extract, 5 g; yeast extract, 5 g; $KH_2PO_4$, 5 g; NaCl, 50 g. The optimal culture conditions of S. cerevisiae KFCC 10823 were pH 5.5, $25^{\circ}C$, 200 rpm and 0.5 vvm. Yeast viability during batch fermentation was gradually decreased to a level less than $90{\%}$ after 35 hours. The maximum cell number was $2.2{\times}10_7$ cells/ml at the optimal condition. Doenjang prepared with ethanolic yeast was ripened after 45 days at $30^{\circ}C$. This Doenjang contains 470 mg% of amino nitrogen and 2.5% ethanol. The shelf-life at $30^{\circ}C$ was theoretically estimated as 444 days.

• The Korean Journal of Physiology and Pharmacology
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• 제4권1호
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• pp.73-79
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• 2000

This study investigated whether propofol, an intravenous, non-barbiturate anesthetic, could reduce brain damage following global forebrain ischemia. Transient global ischemia was induced in gerbils by occlusion of bilateral carotid arteries for 3 min. Propofol (50 mg/kg) was administered intraperitoneally 30 min before, immediately after, and at 1 h, 2 h, 6 h after occlusion. Thereafter, propofol was administered twice daily for three days. Treated animals were processed in parallel with ischemic animals receiving 10% intralipid as a vehicle or with sham-operated controls. In histologic findings, counts of viable neurons were made in the pyramidal cell layer of the hippocampal CA1 area 4 days after ischemia. The number of viable neurons in the pyramidal cell layer of CA1 area was similar in animals treated with a vehicle or a subanesthetic dose of propofol. In terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) assay, semiquantitative analysis of dark-brown neuronal cells was made in the hippocampal CA1 area. There was no significant difference in the degree of TUNEL staining in the hippocampal CA1 area between vehicle-treated and propofol-treated animals. These results show that subanesthetic dose of propofol does not reduce delayed neuronal cell death following transient global ischemia in Mongolian gerbils.

• Journal of Breast Disease
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• 제6권2호
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• pp.39-45
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• 2018

Purpose: Dieckol, a phlorotannin compound isolated from Ecklonia cava, has been reported to have antioxidant, antiviral, anti-inflammatory, and anticancer properties. The purpose of this study was to investigate its anticancer effects on human breast cancer cell lines. Methods: In this study, the viability of two human breast cancer cell lines SK-BR-3 and MCF-7 was investigated after dieckol treatment using a WST-1 assay. Apoptosis and cell cycle distribution were assayed via Annexin V-fluorescein isothiocyanate and propidium iodide staining followed by flow cytometric analysis. Immunoblotting analysis was also performed using Bax/Bcl-2 to determine whether the dieckol-induced apoptosis was mediated by the intrinsic apoptotic pathway. Results: In a dose dependent manner, dieckol reduced the number of viable cells and increased the number of apoptotic cells. The effect of dieckol on the cell cycle distribution was analyzed using flow cytometry. Dieckol treatment significantly increased the percentage of MCF-7 and SK-BR-3 in the G2/M phase. Immunoblot analysis revealed that 24 hours of dieckol exposure increased the Bax/Bcl-2 ratio. Conclusion: Dieckol induced cytotoxicity in MCF-7 and SK-BR-3 human breast cancer cells inducing apoptosis and cell cycle arrest. Therefore, it is suggested that dieckol may be a potential therapeutic agent for breast cancer.

• 미생물학회지
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• 제37권3호
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• pp.234-238
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• 2001

배추김치와 부추김치의 발효양상을 비교하기 위해 $20^{\circ}C$와 $10^{\circ}C$로 나누어 발효과정 중의 총 균수, 젖산균 수, pH 및 총 당함량을 비교 분석하였다. $20^{\circ}C$에서 발효한 배추김치의 경우 총 균수와 Leuconastoc속과 Lactobacillus속 젖산균 모두 발효 초기인 2일째에 최대에 도달하다가 그 이후에는 점점 감소하였다. 그러나 $20^{\circ}C$에서 발효한 부추김치의 경우에는 Leucanostoc속은 발효 3일째에 최대에 도달한 후 점차 감소하였지만 Lactobacillus속은 발효 15일 이후까지 그 균수가 유지되었다. $10^{\circ}C$에서 발효한 경우에는 배추김치, 부추김치 모두 $20^{\circ}C$에서 발효한 경우보다 Leuconostoc속과 Lactobacillus 속의 균수가 서서히 중가하다가 감소하였다. pH 변화는 배추김치 경우에는 3일 후에 적숙기 김치의 pH인 4.2 부근에 도달한 후 발효 5일째에 3.5 까지 낮아져 그 후에도 계속 유지되었으나 부추김치의 경우에는 발효 10일째까지 적숙기 김치의 pH인 4.2 이상으로 유지되었다. $10^{\circ}C$의 경우 배추김치는 6일 후 pH 4.2 정도였으나 부추김치는 24일 후에도 pH 4.2 이상으로 유지하였다. 발효 기간에 따른 총 환원당의 함량은 배추김치와 부추김치 모두에서 발효초기부터 발효가 진행됨에 따라 계속적으로 감소하였지만 $10^{\circ}C$에서 발효한 부추김치의 경우에는 감소정도가 매우 완만하였다. 이상의 결과로부터 부추김치가 배추김치보다 젖산균의 종식이 더디어 배추김치에 비해 발효가 서서히 진행됨을 알았다.

• 한국식품영양학회지
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• 제21권2호
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• pp.176-183
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• 2008

This study examined the anti-microbiological effects of chlorine treatment on the surface of fresh fruits, in order to improve microbiological safety in school foodservice operations. Non-peeled fruit(strawberries) and peeled fruit(bananas) were treated with different concentrations of chlorinated water and rinsing numbers, followed by microbiological testing. The fruits were immersed at different concentrations of chlorinated water(0 ppm, 50 ppm, and 100 ppm) and durations(3 min and 5 min), and were then rinsed with tap water(one time, two times, or three times). The total viable cell counts of both the strawberries and bananas ranged from $10^3$ CFU/g to $10^4$ CFU/g, and coliform levels ranged from $10^2$ CFU/g to $10^3$ CFU/g. As the chlorine concentration, immersion time, and rinsing number increased, anti-microbiological activity increased. The largest microbial reduction was shown with immersion for 5 min in 100 ppm chlorinated water and three rinsings. In the strawberries, this treatment reduced the initial population of total viable cells and coliforms by 3.29 log CFU/g and to an undetectable level, respectively, no total viable cells or coliforms were detected on the banana surface following this treatment. However, after a sterilization treatment with immersion for 5 min in 50 ppm chlorinated water and three rinsings, the total viable cell counts and coliform counts of the strawberries and bananas decreased to acceptable levels, based on the microbiological standards for ready-to-eat foods. Overall, it was shown that the sterilization treatment of 50 ppm chlorinated water, soaking for 5 min, and three rinsings provided an effective reduction in surface microbes, and enhanced the microbiological safety of the fruit.

• Journal of Microbiology and Biotechnology
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• 제6권5호
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• pp.340-346
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• 1996

In order to find out if staphylococci occur in significant numbers in Korean fermented fish products, a total of 40 different fermented fish products were collected from different markets in Korea and analyzed for their physico-chemical and microbiological states. The pH, salt concentration and water activity of the products were measured and the total viable cell count and the number of Staphylococcus grown on mannitol salt agar were determined. The identification of the strains of Staphylococcus were made by API Staph Strip and MIS identification kits, and the physiological properties of the identified strains were further characterized by different conventional methods. The pH, salt content and water activity of fermented fish samples varied widely from 4.8 to 7.1, 7.4-28.7$%$ and 0.77-0.84, repectively, depending on the type of product. The total viable cell count varied from $10^4-10^9$ cfu/ml, and most of the samples had $10^5-10^6$ cfu/ml No correlation was found between the viable cell count and the pH, NaCl concentration and water activity of the samples. Among the 35 colonies identified as Staphylococcus strains by the identification kits, S. xylosus was the most frequently occurring strain marking 17, and S. warneri was 8, S. epidermidis 4 and S. cohnii 2. S. hominis, S. saprophyticus, S. haemolyticus and S. aureus were also identified once each. In some samples (K-3, P-6, K-8, G-5 and G-10), 2-3 different species of Staphylococcus were found. Considering the region of sampling, among the 10 samples from Kunsan 5 were identified as S. warneri, while in the other regions S. xylosus was predominant. Although the physiological characteristics of the identified strains were generally consistent with those in Bergey's Manual, some discrepances were also observed. All the strains were highly salt tolerant, growing in the media containing over 18$%$ NaCl. All the strains except S. aureus (G-11) showed negative in hemolysis activity, plasma coagulation and DNase tests. All the strains including S. aureus (G-11) showed negative in enterotoxin test.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.918-922
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• 2001

In a previous study, we have isolated a number of lactobacilli from Korean women, and one of them (KLB46) was identified as Lactobacillus crispatus by 16S rRNA gene sequencing. For the ecological treatment of bacterial vaginosis (BV) cell suspension of L. crispatus KLB46 was instillated into BV patients. L. crispatus KLB46 was found to persist for several days in cell suspension with no nutrients. In this study, in order to assess the influence of starvation on physiological activity, we compared the viability and culturability of KLB46 following suspension in various buffer solutions. A pair of in situ fluorescent dye was used to assess viability (i.e. membrane integrity) and the culturability was examined by plate count assay. A rapid epifluorescence staining method using the LIVE/DEAD Bacterial Viability Kit $(BacLight^{TM})$ was applied to estimate both viable and total counts of bacteria in cell suspension. $BacLight^{TM}$ is composed of two nucleic acid-binding stains ($SYTO\;9^{TM}$ and propidium iodide). $SYTO\;9^{TM}$ penetrates all bacterial membranes and stains the cells green while propidium iodide only penetrates cells with damaged membranes, therefore the combination of the two stains produces red fluorescing cells. Optimal staining conditions for $BacLight^{TM}$ were found to be with 0.0835M $SYTO\;9^{TM}$ and 0.05M propidium iodide for 15 min incubation at room temperature in dark. When cells were microscopically examined during 140 hours of starvation, the culturability decreased markedly while the viability remained relatively constant, which suggests that large fraction of KLB46 cells became viable but non-culturable (VBNC) upon starvation.

• 한국식품과학회지
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• 제28권4호
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• pp.730-735
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• 1996

마늘이 상처를 입으면 마늘중에 존재하는 alliin이 alliinase에 의해 allicin으로 분해되며 allicin은 마늘의 주된 항미생물 작용 물질로 알려져 있다. 이 성분에 의한 미생물번식 저해작용을 크게 받는 E. coli는 1%의 마늘즙액이 들어있는 TSB에서 사멸효과가 나타났으며 농도가 높을수록 사멸속도는 더욱 빨랐다. 마늘즙액에 의한 미생물생육 저해효과는 pH에 따라서도 다르게 나타나는데 pH 7.2에 비해 5.2와 6.2에서 저해작용이 강하게 나타났다. 초기 접종균수가 $10^{6}\;CFU/ml 이상일 때는 번식에 대한 저해효과가 나타나지 않았으나 $10^{5}\;CFU/ml 이하일 때는 저해효과가 나타나서 항미생물 작용에 대한 초기 미생물 수도 중요한 변수였다. 유리 SH기를 가진 cysteine이나 glutathione을 첨가하면 마늘즙액의 번식 저해효과로부터 E. coli를 보호하였다. 결과적으로 E. coli에 대한 마늘즙액의 번식 저해효과는 마늘즙액의 농도뿐만 아니라 pH, cystein이나 glutathione같은 SH화합물의 존재여부, 접종균수에 의해서 영향을 받음을 알 수 있었다.