• 한국환경농학회지
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• 제41권4호
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• pp.344-354
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• 2022

BACKGROUND: Although antibiotics have contributed to treatment of bacterial infection, the antibiotic abuse can lead to antibiotic resistant bacteria. Impact of human activities on distribution of antibiotic resistance has been intensively issued and occurrence of antibiotic resistant bacteria in contaminated environments would not be a surprise. Nonetheless, anthropogenic contamination with the dissemination of antibiotic resistance along uncontaminated environments has been less considered. The aim of this study is to investigate antibiotic resistant bacteria across Ulleungdo, known as antibiotic resistance free and anthropogenic pollution free environment in Rep. of Korea. METHODS AND RESULTS: Antibiotic resistant bacteria in coastal seawater of Ulleungdo were investigated in July 2021. Antibiotic susceptibility test using the disk diffusion method was applied with six drugs according to the Clinical and Laboratory Standards Institute (CLSI) guideline. Total 43 bacterial isolates were tested and 20 isolates among of them showed multidrug resistance. Particularly, the number and ratio of resistant bacteria were relatively high in a densely populated area of Ulleungdo. The bacterial communities were investigated using 16S rRNA gene metabarcoding approach in the coastal seawater and soils of Ulleungdo. In the bacterial communities, Firmicutes were selectively distributed only in seawater, suggesting the possibility of anthropogenic contamination in coastal seawater of Ulleungdo. CONCLUSION(S): We found antibiotic resistant bacteria in a populated area of Ulleungdo. The occurrence of antibiotic resistant bacteria in Ulleungdo seems to result from the recent anthropogenic impact. Consistent monitoring of antibiotic resistant bacteria in the uncontaminated environment needs to considered for future risk assessment of antibiotics.

• Tuberculosis and Respiratory Diseases
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• 제43권1호
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• pp.14-21
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• 1996

연구배경: 다제 내성 폐결핵 환자의 임상적 특성과 약제별 내성률, 치료에 영향을 미치는 인자, 이차 약제로 인한부작용, 치료내용 및 차료성적 등을 살펴 보고자 하였다. 대상: 약제 감수성 검사상 두가지 이상의 일차 약제에 동시 내성을 보이는 환자를 대상으로 후향성 연구를 시행하였다. 치료 결과의 판정은 정기적으로 6개월 이상 추적 관찰이 가능했던 환자만을 대상으로 치료후 호전을 1개월 이상의 간격으로 시행한 가래 검사상 3회 이상 음성이고 방사선 소견이 호전되거나 6개월 이상 변화가 없는 경우로, 치료 실패를 6개월간의 치료에도 균 음전화가 되지 않거나 방사선 소견상 악화를 보이는 경우로 정의하였다. 대상 환자들은 감수성 검사 결과에 따라 감수성 약제를 4제 이상 투여하여 치료받았다. 결과: 1) 총 71예와 환자를 대상으로 조사한 결과 35예(49%)에서 방사선상 공동을 관찰할 수 있었고 평균 4.1개의 약물에 내성을 지니고 있었는데 90%가 INH, RFP 동시 내성을 보였다. 2) 치료 결과의 판정이 가능하였던 55예중 35예(67%)의 환자가 치료후 호전을 보였으며 치료 실패는 18예(33%)이었다. 일차 내성 환자가 5예이었는데 치료 결과 판정이 가능하였던 4예는 모두 치료에 성공하였다. 3) 약제 부작용은 14예(20%)에서 나타났는데 간기능 악화가 6예로 가장 많았고 어지러움증 5예, 고요산 혈증을 동반한 관절통이 3예, 이명 3예 등의 순이었다. 이들 부작용의 절반 이상이 투약후 3개월 이내에 발생 하였다. 4) 약제 감수성 검사를 반복했을 때 INH, RFP의 경우 100% 가까운 일치율을 보였고 EMB, PZA 80% 정도 나머지 약물은 50% 미만이었다. 5) 5예의 환자가 수출을 받았고 이 중 1예는 항결핵 화학 요법의 보조적 치료로 수술을 했는데 균 음전화에 성공하였다. 결론: 다제 내성 폐결핵 환자에서도 규칙적인 약물 복용과 적절한 처방으로 약 2/3 정도에서 호전이 관찰되어 적극적인 항결핵 화학 요법을 시행해야 할 것으로 생각되지만 치료와 예후 판정에 도움이 되는 인자를 찾지는 못하였다.

• Tuberculosis and Respiratory Diseases
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• 제60권4호
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• pp.404-411
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• 2006

목적 : 지난 3년간 전국적으로 항결핵제에 대한 감수성검사를 시행 받은 환자의 실제 수를 파악함으로 국내 다제내성 결핵의 현황을 파악하고자 하였다. 방법 : 2000년 1월부터 2002년 12월까지 3년간 국내의 결핵 약제감수성검사를 시행하고 있는 7개 국립 및 민간검사기관에서 시행된 검사결과들을 후향적으로 조사하여 이를 근거로 국내 결핵환자 중 다제내성 결핵환자의 연도별 현황 및 추이 등 다제내성 결핵환자의 실제현황을 조사 분석하였다. 결과 : 6개의 검사기관은 절대농도법을 사용하였고 한 개의 기관에서 비율법을 사용하였다. 2000년부터 2002년까지 매년 18,071, 19,950, 그리고 21,919건의 검사가 시행되었다. 한 가지 이상의 약제에 내성으로 진단된 내성결핵 환자의 수는 2000년 6,338명에서 2002년 7,409명으로 16.9% 증가하였다. 약제감수성검사가 시행된 전체 환자들 중 내성결핵으로 진단된 환자의 비율은 2000년 35.1%, 2001년 34.5%, 그리고 2002년 33.8%이었다. 다제내성 결핵으로 확인된 환자는 2000년에 3,708명에서 2002년 4,245명으로 14.5% 증가하였다. 결론 : 2002년에 약 4,000여건의 새로운 다제내성 결핵이 약제감수성검사에 의해 확인되었으며 매년 증가하는 경향을 보였다. 검사실간의 약제감수성검사의 표준화 작업과 보다 효과적인 다제내성 결핵의 관리가 요구 된다.

• Tuberculosis and Respiratory Diseases
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• 제77권4호
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• pp.161-166
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• 2014

Since tuberculosis (TB) remains a major global health concern and the incidence of multi-drug resistant (MDR)-TB is increasing globally, new modalities for the detection of TB and drug resistant TB are needed to improve TB control. The Xpert MTB/RIF test can be a valuable new tool for early detection of TB and rifampicin resistance, with a high sensitivity and specificity. Late-generation fluoroquinolones, levofloxacin, and moxifloxacin, which are the principal drugs for the treatment of MDR-TB, show equally high efficacy and safety. Systemic steroids may reduce the overall TB mortality attributable to all forms of TB across all organ systems, although inhaled corticosteroids can increase the risk of TB development. Although fixed dose combinations were expected to reduce the risk of drug resistance and increase drug compliance, a recent meta-analysis found that they might actually increase the risk of relapse and treatment failure. Regarding treatment duration, patients with cavitation and culture positivity at 2 months of TB treatment may require more than 6 months of standard treatment. New anti-TB drugs, such as linezolid, bedaquiline, and delamanid, could improve the outcomes in drug-resistant TB. Nontuberculous mycobacterial lung disease has typical clinical and immunological phenotypes. Mycobacterial genotyping may predict disease progression, and whole genome sequencing may reveal the transmission of Mycobacterium abscessus. In refractory Mycobacterium avium complex lung disease, a moxifloxacin-containing regimen was expected to improve the treatment outcome.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.946-950
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• 2015

Recently, it has become a struggle to treat tuberculosis with the current commercial antituberculosis drugs because of the increasing emergence of multidrug-resistant (MDR) tuberculosis and extensively drug-resistant (XDR) tuberculosis. We evaluated here the antimycobacterial activity of tamoxifen, known as a synthetic anti-estrogen, against eight drugsensitive or resistant strains of Mycobacterium tuberculosis (TB), and the active intracellular killing of tamoxifen on TB in macrophages. The results showed that tamoxifen had antituberculosis activity against drug-sensitive strains (MIC, 3.125-6.25 µg/ml) as well as drugresistant strains (MIC, 6.25 to 12.5 µg/ml). In addition, tamoxifen profoundly decreased the number of intracellular TB in macrophages in a dose-dependent manner.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.21-22
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• 2003

Fungicide treatment is the most important method for the control of plant diseases caused by phytopathogenic fungi. But fungicide resistant strains have appeared in many phytopathogenic fungi. Until now, molecular mechanisms of fungicide resistance such as mutation of target protein, overproduction of target enzyme and detoxification of fungicide have been designated. Recently, it was demonstrated that active efflux of fungicides mediated by ATP-binding cassette (ABC) transporters also contributes to fungicide resistance in several filamentous fungi, such as Aspergillus nidulans, Penicillium digitatum and Botrytis cinerea.(중략)

• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2007년도 추계국제학술대회 및 컨퍼런스
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• pp.592-592
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• 2007

• Journal of Yeungnam Medical Science
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• 제28권2호
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• pp.133-144
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• 2011

Background: Tigecycline (TIG), a new broad-spectrum glycylcycline with anti-multidrug-resistant-(MDR)-pathogen activity, was launched in March 2009 in South Korea, but there are insufficient clinical studies on its use in the country. As such, this study was performed to analyze cases of severe MDR-pathogen-caused infections treated with TIG. Methods: Patients treated with TIG within the period from May 2009 to June 2010 were enrolled in this study. Their clinical and microbiologic data were reviewed retrospectively. Results: Twenty-one patients were treated with TIG for complicated skin and soft-tissue infections (cSSTIs) (42.9%), complicated intra-abdominal infections (cIAIs) (38.1%), or pneumonia (19.1%) caused by MDR pathogens like carbapenem-resistant $Acinetobacter$ $baumannii$ (76.2%), methicillin-resistant $Staphylococcus$ $aureus$ (61.9%), extended-spectrum beta-lactamase-producing $Escherichia$ $coli$ and $Klebsiella$ $pneumoniae$ (38.1%), and penicillin-resistant $Enterococcus$ species (33.3%). Thirteen patients (61.9%) had successful clinical outcomes while five (23.8%) died within 30 days. The rate of clinical success was highest in cSSTI (77.8%), followed by cIAI (50%) and pneumonia (50%), and the mortality rate was highest in pneumonia (50%), followed by cIAI (25%) and cSSTI (11.1%), Conclusion: Tigecycline therapy can be an option for the treatment of severe MDR-pathogen-caused infections in South Korea, Due to its high risk of failure and mortality, however, prudence is required in its clinical use for the treatment of severe infections like nosocomial pneumonia.

• Tuberculosis and Respiratory Diseases
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• 제43권6호
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• pp.862-870
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• 1996

Background : Multidrug-resistant tuberculosis(MDR-Tb) has been increased not only in Asia but also in Western society, which may cause public health problems and reduce the efficacy of treatment of tuberculosis. In Western society HIV infection is believed to do a central role in increasing incidence of MDR tuberculosis, but MDR-Tb in Korea may be somewhat different about clinical features, underlying disorders, and prognosis. Goble et al reponed that overall treatment failure rate in MDR-Tb including resistance to isoniazid(INH) and rifampin (RFP) was 44 %. The aim of this study is to find the treatment result in Korea and the factors determining the prognosis. Methods: A retrospective study of pulmonary tuberculosis cultured M. tuberculosis from sputum or bronchial washing fluid between 1986 through 1992 was conducted in the Seoul Paik Hospital, Inje University. We reviewed clinical courses of 141 patients, who had a tuberculosis with resistance to 2 or more drugs including isoniazid(INH) and rifampin(RFP). One hundred and 4 patients of 141 patients had completed treatment and followed up for more than one year. Results: Of 104 (mean age $43.6{\pm}16.7$, M: F=63 : 41) patients with sufficient follow-up data, 73(84.6%) patients responded which is defined as negative Sputum cultures for at least 3 consecutive months. Seven patients(6.7%) had a failure in negative conversion and 9(8.7%) of the patients who initially responded relapsed. Overall treatment failure rate was 15.4%, Patients who were treated for less than 12 months had a higher relapse rate(12.3%) than 18 months(4.9%). And there was a statistically significant correlation between the relapse rate and the number of drugs to which isolates wera resistant(p<0.05). Conclusion : The treatment failure rate of MDR-Tb in Korea was lower than previous studies in western Country and the major determining factor of prognosis was the number of resistant drugs to M. tuberculosis at drug sensitivity test. For reducing the relapse rate, we recommend more than 12 months of treatment for MDR tuberculosis.

• Natural Product Sciences
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• 제11권3호
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• pp.136-138
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• 2005

Bioassay-guided fractionation of an organic extract of the broth from the marine-derived fungus of the genus Aspergillus led to the isolation of the polyketides, (+)-epoxydon (1), (+)-epoxydon monoacetate (2), gentisyl alcohol (3), 3-chlorogentisyl alcohol (4), and methylhydroquinone (5). Compounds 1-5 showed a potent antibacterial activity against the methicillin-resistant and multidrug-resistant Staphylococcus aureus (MRSA and MDRSA) with MIC (minimum inhibitory concentration) values of 12.5, 12.5, 12.5, 50.0, and $6.2\;{\mu}g/mL$, respectively. Compounds 1-4 also exhibited a significant radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) with $IC_{50}$ values of 6.0, 15.0, 7.0, and $1.0\;{\mu}M$, respectively.