• 생명과학회지
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• 제29권1호
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• pp.84-89
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• 2019

신규 항세균물질을 탐색하는 사전조사에서 몇몇 분리균주들이 그람양성 세균과 그람음성 세균 모두에 항균활성을 보이며, 심지어 methicillin내성 Staphylococcus aureus (MRSA)에도 항균활성을 나타내었다. 이들 균주 중에서 한 균주가 표현형과 계통분석을 이용하여 특히 16S 리보좀 RNA 유전자 염기서열에 기초하여 Pseudomonas aeruginosa로 동정되었다. BCNU 1204 균주의 항균물질은 King's medium B (pH 7.0)에서 $35^{\circ}C$의 온도 조건으로 4일 배양 후 가장 최대로 생산되었다. 항균물질을 각종 유기용매로 분획한 결과, P. aeruginosa BCNU 1204의 dichloromethane (DCM)분획과 ethylacetate (EA) 분획이 그람 양성 세균에 강력한 항균활성을 보였으며, 특히 ethylacetate (EA) 분획이 methicillin내성 Staphylococcus aureus (MRSA)에 대하여 강한 항균활성을 나타내었다. Recycling preparative LC와 preparative TLC 로 활성물질 하나(분획 5-2)를 분리하여 GC-MS 분석한 결과 phenazine 화합물에 속하는 phenazine-1-carboxylic acid 로 동정하였다. 그리고 MRSA 균주에 대한 최소저해농도(minimum inhibitory concentration, MIC)가 MRSA균주인 CCARM 3089, 3090, 3091 그리고 3095 균주에 대하여 각각 $25{\mu}g/ml$, $50{\mu}g/ml$, ${\geq}25{\mu}g/ml$ 그리고 ${\geq}50{\mu}g/ml$ 임을 확인하였다. 그러므로 P. aeruginosa BCNU 1204 분리균주는 항 MRSA 항생물질을 개발하기 위한 잠재 가치가 높은 생물자원으로 기대되며, P. aeruginosa BCNU 1204 균주로부터 리더 화합물을 획득하기 위한 보다 많은 연구가 요구된다.

• 식물병연구
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• 제29권4호
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• pp.405-413
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• 2023

당근 세균잎마름병을 일으키는 Xanthomonas hortorum pv. carotae는 당근 생산량에 큰 피해를 주는 병 중 하나로 국내에서 아직 방제에 대한 연구가 미흡한 실정이다. 본 연구에서는 당근 세균잎마름병균에 효과적인 농약을 선발하기 위하여 3종의 항생제 streptomycin, oxolinic acid, kasugamycin, 2종의 구리제 copper hydroxide, copper sulfate basic 그리고 길항근권세균 Burkholderia gladioli MRL408-3, Pseudomonas fluorescens TRH415-2, Bacillus cereus KRY505-3을 선정하여 인공배지를 이용하여 이들의 직접적인 항균효과를 조사하였다. 이 중 항생제 streptomycin, oxolinic acid와 길항미생물 MRL408-3을 처리한 배지에서 억제환이 형성되었다. 당근 잎에 농약과 항균효과를 보였던 길항미생물 MRL408-3을 전처리한 후 당근 세균잎마름병균을 접종하였더니 streptomycin과 oxolinic acid을 전처리한 당근 잎에 높은 방제효과를 보였다. 이들 당근 잎 표면의 장방출주사현미경 이미지에서 streptomycin과 oxolinic acid를 전처리한 잎에서는 세균 수가 무처리한 잎과 비교하여 급격히 감소하였다. 이들 결과를 통해 streptomycin과 oxolinic acid와 같은 항생제가 다른 약제에 비해 방제 효과가 뛰어나다는 것을 알 수 있었다. 본 연구는 당근 세균잎마름병에 대한 이상적인 방제 시스템을 구축하는 데 도움이 되는 자료로서 가치가 있을 것으로 생각된다.

• 한국안광학회지
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• 제10권4호
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• pp.283-292
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• 2005

본 연구는 가토안에서 나린진과 키토산의 효능을 조사하였다. 나린진의 주성분은 자몽씨 추출물로서 이는 항산화, 항균, 항암제로서 널리 알려져 있다. 이는 식품보존제와 화장품에 널리 사용된다. 또다른 천연 보존제중 하나인 키토산은 식품보존제, 건강음료, 차에 사용되며, 갑각류의 외피나 곤충의 표피, 곰팡이 및 효모 등의 세포벽에 널리 분포되어 인체에 독성이 없으면서도 다양한 미생물에 대해 항균성을 보이는 천연항균제로 알려져 있다. 본 연구의 목적은 소프트콘택트렌즈를 장용함으로써 각 결막 독성과 감염을 일으키는 화합보존제를 대체할 천연 보존제의 적당한 농도를 찾는 것이다. 본 연구는 LM과 TEM을 사용하여 각막상피, 내피를 형태학적으로 비교하였다. In vivo 방법으로, 나린진과 키토산을 가토안의 안구에 직접 3-4방울을 일주일간 하루 4차례씩 점안하였다. 안구 적출 후, LM과 TEM을 통하여 각막의 손상상태를 관찰하였다. 손상된 세포는 대체적으로 키토산이 나린진보다 심하였다. 하지만 나린진도 1%의 농도에서는 세포에 손상을 주었다. 콘택트렌즈 보존제로서 가장 중요한 요건은 적당한 농도를 사용하는 것이다.

• 한국식품과학회지
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• 제37권3호
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• pp.456-464
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• 2005

본 연구에서는 최근 전세계적으로 문제가 되고 있는 항생제 내성균에 대해 그 항균효과를 천연의 약용식물을 이용하여 분자생물학적 수준에서 비교해보고 천연항균제의 개발에 우선하여 직접 식품에 첨가하여 그 효과를 검색하고자 하였다. 병원내감염의 주된 원인균으로 알려진 황색포도상구균(Staphylococcusaureus)은 여러 항균제에 대하여 내성을 획득함으로써 질병의 치료를 어렵게 한다는 점에서 매우 심각한 문제이다. 이러한 내성균은 다양한 방법으로 동 식물에 빠르게 전파되고 있으므로 소비자가 내성균을 지닌 식품을 섭취해 잠재적인 내성균을 보유하게 되는 결과를 낳게 된다. 이러한 항생제 내성 황색포도상구균(Methicillin Resistant S. aureus, MRSA)에 대해 천연 약용 식물 중 우수한 항균력을 가지는 감초를 순차 분획하여 각 분획물을 이용한 MRSA에 대한 항균 활성을 알아본 결과 hexane, chloroform 분획물에서 항균활성을 나타냈으며, 동일농도의 생육저해비교 실험에서 대부분의 내성균주에 대해 대조군과 유사한 효과를 나타낸 penicillin에 비해 감초분획물이 대수기를 넘는 억제효과를 나타내었으며 이 중 chloroform 분획물이 가장 높은 저해활성을 나타내었다. 또한 RT-PCR을 통하여 표준균주와 내성균주의 내성 정도와 내성 유전자를 관찰해본 결과 KCCM 40510은 내성획득유전자인 mecA, mecRI, mecI, femA에 발현이 높게 나타나 고도내성균임을 알 수 있었으며, 고도내성을 나타내는 균주를 이용하여 감초의 chloroform 분획물을 농도별로($50,\;100,\;250\;{\mu}/mL$) 처리한 결과 농도 의존적으로 유전자 발현이 억제됨을 볼 수 있었다. 특히 고도내성균주인 KCCM 40510은 메티실린 내성을 상승시키는 mecA 유전자의 발현을 억제시키는 mecRI 유전자의 pathway와 상응하는 것으로 보여지므로 감초가 이러한 고도내성균에 효과가 있음을 알 수 있었다. 또한 SEM을 통한 형태학적 관찰을 통해 분획물 처리 시 세포벽이 파괴되는 것을 확인할 수 있었다. 한편 이러한 감초추출물을 직접 식품에 첨가하여 내성 균주에 대한 억제 효과도 확인한 결과 추출물 200mg/100mL 농도에서 포도상구균에 대해 항균효과를 나타내는 것을 볼 수 있었다.

• 한국임상약학회지
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• 제27권3호
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• pp.186-194
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• 2017

Objectives: A significant concern has been raised about the emerging resistance that is largely caused by the excessive or inappropriate use of antibacterial agents for viral respiratory infections. This study investigated the trend of respiratory tract infections (RTIs) and the use of antibiotics. Methods: Utilizing the national level health insurance claims data from 2005 to 2008, we examined encounter days, antibiotic use, and the prescription rate for respiratory tract infections including upper respiratory tract infections (URTIs), lower respiratory tract infections (LRTIs), and otitis media in outpatient settings. The antibiotic use was measured as defined daily dose per 1,000 patients per day (DDD/1,000 patients/day). Results: The visit for URTI increased from 141,693,465 in 2005 to 120,717,966 in 2008 and the visit for LRTI decreased from 61,778,718 to 66,930,122. For RTIs, prescription rates of antibiotics decreased from 65.2% to 58.5% for URTIs and 76.9% to 68.3% for LRTIs from 2005 to 2008. The antibiotic use decreased to 20.85 DDD/1,000 patients/day after a significant increase of 22.01 DDD/1,000 patients/day in 2006. Among antibiotics, J01CR had the highest use- 7.93 DDD/1,000 patients/day followed by J01DC of 3.71 DDD/1,000 patients/day and J01FA of 3.2 DDD/1,000 patients/day. One notable trend is that J01FA presented a continuous increase in antibiotic use from 2.3 in 2005 to 3.26 DDD/1,000 patients/day in 2008. Conclusion: The use of antibiotics had poor compliance to guidelines for RTIs. Despite decrease in the use of antibiotics, prescription rates for URTIs were still about 50% indicating that the delayed prescribing antibiotics (or wait-and-see) were not observed.

• The Korean Journal of Physiology and Pharmacology
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• 제19권2호
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• pp.99-104
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• 2015

The aim of this study is to develop a physiologically based pharmacokinetic (PBPK) model in intra-abdominal infected rats, and extrapolate it to human to predict moxifloxacin pharmacokinetics profiles in various tissues in intra-abdominal infected human. 12 male rats with intra- abdominal infections, induced by Escherichia coli, received a single dose of 40 mg/kg body weight of moxifloxacin. Blood plasma was collected at 5, 10, 20, 30, 60, 120, 240, 480, 1440 min after drug injection. A PBPK model was developed in rats and extrapolated to human using GastroPlus software. The predictions were assessed by comparing predictions and observations. In the plasma concentration versus time profile of moxifloxcinin rats, $C_{max}$ was $11.151{\mu}g/mL$ at 5 min after the intravenous injection and $t_{1/2}$ was 2.936 h. Plasma concentration and kinetics in human were predicted and compared with observed datas. Moxifloxacin penetrated and accumulated with high concentrations in redmarrow, lung, skin, heart, liver, kidney, spleen, muscle tissues in human with intra-abdominal infection. The predicted tissue to plasma concentration ratios in abdominal viscera were between 1.1 and 2.2. When rat plasma concentrations were known, extrapolation of a PBPK model was a method to predict drug pharmacokinetics and penetration in human. Moxifloxacin has a good penetration into liver, kidney, spleen, as well as other tissues in intra-abdominal infected human. Close monitoring are necessary when using moxifloxacin due to its high concentration distribution. This pathological model extrapolation may provide reference to the PK/PD study of antibacterial agents.

• 대한약침학회지
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• 제19권4호
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• pp.312-318
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• 2016

Objectives: Bacterial resistant infections have become a global health challenge and threaten the society's health. Thus, an urgent need exists to find ways to combat resistant pathogens. One promising approach to overcoming bacterial resistance is the use of herbal products. Green tea catechins, the major green tea polyphenols, show antimicrobial activity against resistant pathogens. The present study aimed to investigate the effect of catechins, green tea extract, and methylxanthines in combination with gentamicin against standard and clinical isolates of Staphylococcus aureus (S. aureus) and the standard strain of Pseudomonas aeruginosa (P. aeruginosa). Methods: The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values of different agents against bacterial strains were determined. The interactions of green tea extract, epigallate catechin, epigallocatechin gallate, two types of methylxanthine, caffeine, and theophylline with gentamicin were studied in vitro by using a checkerboard method and calculating the fraction inhibitory concentration index (FICI). Results: The MICs of gentamicin against bacterial strains were in the range of $0.312-320{\mu}g/mL$. The MIC values of both types of catechins were $62.5-250{\mu}g/mL$. Green tea extract showed insufficient antibacterial activity when used alone. Methylxanthines had no intrinsic inhibitory activity against any of the bacterial strains tested. When green tea extract and catechins were combined with gentamicin, the MIC values of gentamicin against the standard strains and a clinical isolate were reduced, and synergistic activities were observed (FICI < 1). A combination of caffeine with gentamicin did not alter the MIC values of gentamicin. Conclusion: The results of the present study revealed that green tea extract and catechins potentiated the antimicrobial action of gentamicin against some clinical isolates of S. aureus and standard P. aeruginosa strains. Therefore, combinations of gentamicin with these natural compounds might be a promising approach to combat microbial resistance.

• ALGAE
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• 제30권3호
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• pp.241-246
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• 2015

This research was conducted to develop effective and safe marine-derived antiviral compounds against norovirus. The ethyl acetate (EtOAc)-extract from Eisenia bicyclis exhibited strong antiviral activity against murine norovirus (MNV) as a norovirus surrogate. Among the phlorotannins from E. bicyclis, dieckol (DE) and phlorofucofuroeckol-A (PFF) were known to possess the strongest antibacterial activity. In this study, DE and PFF were evaluated for antiviral activity against MNV. DE and PFF exhibited strong anti-MNV activity with 50% effective concentration ($EC_{50}$) of $0.9{\mu}M$. However, PFF exhibited more effective antiviral activity against MNV with higher selective index (668.87) than that of DE (550.60), due to its lower cell toxicity against RAW 264.7. This is the first report on the anti-MNV activity of phlorotannins from seaweed. The results obtained in this study suggest that the phlorotannins could be used as a potential source of natural antiviral agents.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.756-764
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• 2014

Apoptin, a chicken anemia virus-encoded protein, induces apoptosis in chicken or human tumor cells, localizing in their nuclei as opposed to the cytoplasm of non-transformed cells. The present study was undertaken to investigate whether ABPs1 could potentiate apoptin-induced apoptosis in HeLa cells. ABPs1 and the apoptin genes were successfully cloned into pIRES2-EGFP expression vector and expressed in HeLa cells. We report that ABPs1 augments apoptin cell growth inhibition in a concentration- and time-dependent manner. The DAPI staining and scanning electron microscopy observations revealed apoptotic bodies and plasma membrane pores, which were attributed to apoptin and ABPs1, respectively. Further, ABPs1 in combination with apoptin was found to increase the expression of Bax and to decrease the expression of survivin compared with either agent alone or the control. The apoptotic rate of HeLa cells treated with ABPs1 and apoptin in combination for 48 h was 53.95%. The two-gene combination increased the caspase-3 activity of HeLa cells. Taken together, our study suggests that ABPs1 combined with apoptin significantly inhibits HeLa cell proliferation, and induces cell apoptosis through membrane defects, up-regulation of Bax expression, down-regulation of survivin expression, and activation of the caspase-3 pathway. Thus, the combination of ABPs1 and apoptin could serve as a means to develop novel gene therapeutic agents against human cervical cancer.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권5호
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• pp.312-315
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• 2009

Objective: It is important to sterilize oral cavity with antibacterial agent before surgery for preventing infection. The object of this study was to compare the effect on reduction of salivary bacterial counts according to applied time when povidone-iodine (PVI) and chlorhexidine gluconate (CHX), most broadly used materials in dentistry, were applied intraorally before the surgery. Methods: Sixty subjects were divided into 6 groups. PVI and CHX were applied in each group for 1, 2 and 3 minutes, respectively. Then salivary microbacteria taken before and after applying the materials were cultured using 5% sheep blood agar plate. Results: There was significant difference in reduction of microbacteria in both PVI and CHX and the effect did not show differences depending on time. When applied for a minute, PVI showed somewhat higher reduction rate than CHX, but in the other groups, there was no difference in reduction rate. Conclusion: We found that there was no significant difference in sterilization ability of PVI and CHX in all groups in this study. Therefore, both agents would get sufficient effect when applied for a minute.