• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.637-642
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• 2010

We investigated the prevalence and the molecular characteristics of vancomycin-intermediate Staphylococcus aureus (VISA) among methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from clinical samples at tertiary or general hospitals participating in a nationwide surveillance program for VISA and vancomycin-resistant Staphylococcus aureus (VRSA) in Korea during an 8-week period in each year from 2001 to 2006. Of 41,639 MRSAs isolated, 37,856 were screened and 169 grew on brain heart infusion agar supplemented with 4 ${\mu}g/ml$ vancomycin. A vancomycin MIC of 4 ${\mu}g/ml$ was confirmed for 33 VISA isolates of the 169 isolates. Eighteen of the 33 isolates were classified as hetero-VISA (hVISA) by the population analysis profile (PAP) method. All VISA isolates were susceptible to linezolid, tigecycline, and quinupristin-dalfopristin. Most VISA isolates (MIC 4 ${\mu}g/ml$) showed a PFGE C pattern with sec, seg, and sei enterotoxin genes, including ST5-SCCmec type II, or a PFGE A pattern with sea, including ST239-SCCmec type III.

• 약학회지
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• 제50권2호
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• pp.78-83
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• 2006

VISA and VRE are the main causes of surgical infection, urinary tract infections and bacteremia in hospitals. In this study; we selected VISA (Vancomycin Intermediate resistant Staphylococcus aureus) and VRE (Vancomycin Resistant Enterococcus) isolated from the clinical isolates. One of the isolated strains indicated the high resistance to severel anti-biotics (Vancomycin, Teicoplanin, Mupirocin, Synercid, Ciprofloxacin, Gentamicin, Lincomycin, Cefotaxim, Meropenem). Antimicrobial activity of Bifidobacterium spp. against VISA and VRE were measured. About $10^4$ cells of VISA or VRE were mixed with 1,5 and 9 ml of Bifidobacterium and the final volume was adjusted to 10 ml with brain heart infusion (BHI) broth. The cell suspension was incubated for 3, 6, 9, and 24 hr, serially diluted and then plated on BHI agar plate. As numbers of Bifidobacterium were increased viable cell count of VISA and VRE decreased. The strongest antimicrobial activity of the Bifidobacterium was observed after 9hr incubation in any mixture, almost completely inhibiting the growth of VISA and VRE.

• 대한임상검사과학회지
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• 제43권3호
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• pp.124-132
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• 2011

The aim of this study was to evaluate the effects of the photosensitizer photogem with light-emitting diode (LED) on vancomycin-resistant enterococci (VRE). Two VRE strains isolated from the feces of patients. that was identificated Enterococcus faecium (vanA) and Enterococcus gallinarum (vanC1) using traditional biochemical tests and confirmed VRE genotyping from using polymerase chain reaction. In addition, three strains were used Enterococcus. faecalis CDC-286 (vanA), E. faecalis CDC-583 (vanB) and E. gallinarum CDC-42 (vanC1). To examine the antimicrobial effect of photogem mediated photodynamic therapy (PDT) against, CFU quantification and Disk diffusion antimicrobial susceptibility test were evaluated. The effects of Photodynamic therapy was not associated with genotype. Photogem mediated PDT perfectly inhibited the colony formation of E. faecalis CDC-286. The number of viable bacteria decreased greatly after PDT application with photogem $50{\mu}g/mL$ and energy density of $15J/cm^2$. The diameter of inhibition zone was increased to after PDT more than before PDT. The case of vancomycin disc on E. faecalis CDC-583 and E. galinanum-Patient were changed from resistant to intermediate resistant, from intermediate resistant to susceptable. These results demonstrate that lethal photosensitization of VRE can be achieved using photogem plus 630 nm LED irradiation.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.660-666
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• 2005

The intestinal microbiota are important to the host with regard to resistance they impart against bacterial infections and their involvement in mediating metabolic functions. Lactic acid producing bacteria such as Lactobacillus play an important physiological role in these matters. The aim of the present study was to isolate Lactobacillus sp. that inhibits enteric pathogens. Initially, 17 isolates from healthy Koreans were collected on Lactobacillus selective medium. Resistance of the isolates to antibiotics including rifampicin, streptomycin, clindamycin and vancomycin was measured. One of the isolate was identified as Lactobacillus ruminus on the basis of bacterial cell morphology, cultural characteristic and biochemical characteristics, 16S rRNA sequence analysis and PCR-RAPD. Antimicrobial activity of the bacterium against Vancomycin Intermediate Resistant Staphylococcus aureus (VISA) and Vancomycin-Resistant Enterococci (VRE) was measured. About $10^4$ cells of VISA or VRE were mixed with 1, 5, and 9 mL of L. ruminus SPM 0211 and the final volume was adjusted to 10 mL with brain heart infusion (BHI) broth. The cell suspension was incubated for 3, 6, 9, and 24 h, serially diluted and then plated on BHI agar plates. As numbers of L. ruminus SPM 0211 were increased, viable cell count of VISA and VRE decreased. The strongest antimicrobial activity of SPM 0211 was observed after 9 h incubation in any mixture, almost completely inhibiting the growth of these two bacteria. The results suggest that the freshly isolated L. ruminus SPM 0211 may be used as a pro-biotic microbe that prevents the colonization of enteric pathogens and can thereby promote good gastrointestinal health.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.211.4-211
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• 2005

• Journal of Korean Neurosurgical Society
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• 제43권6호
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• pp.307-310
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• 2008

Limited therapeutic options are available for vancomycin intermediate-resistant Staphylococcus epidermidis (VISE) infections and no optimum therapy has been established. We report a case of VISE skull osteomyelitis that was successfully treated with linezolid. The patient was a 53-year-old man who presented with headache, nausea and dysphasia. Brain computerized tomography (CT) demonstrated a subdural hematoma in the left hemisphere. Craniotomy and hematoma evacuation was performed and he showed good recovery despite a scalp wound infection caused by methicillin-resistant Staphylococcus aureus (MRSA). The organism isolated from the scalp wound was sensitive to vancomycin. The patient was treated with intravenous vancomycin for 44 days. However, he showed a high fever, persistent positive methicillin-resistant Staphylococcus epidermidis (MRSE) blood cultures, and a deteriorating clinical status. He underwent infected skull bone flap removal and linezolid treatment for 35 days. During one year of follow up, he has not had any further episodes of osteomyelitis or fever. Linezolid has shown to be effective agent to eradiate osteomyelitis caused by VISE.

• 약학회지
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• 제51권4호
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• pp.253-258
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• 2007

Bombycis corpus, a batryticated silkworm and white-stiff silkworm, is an oriental drug consisting of the dried larva of silkworm, dead and stiffened due to the infection of Beauveria. An peptidyl antimicrobial molecule was purified from B. corpus by reverse phase-column chromatography and HPLC. Its molecular weight was determined to be 2295.45 by using matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Its antimicrobial activity was diminished by trypsin digestion. It exhibited a broad antimicrobial spectrum against not only Gram-negative, but also Gram- positive bacteria. Furthermore, it was found to have an antimicrobial activity against vancomycin-resistant enterococci (VRE), methicillin-resistant S. arureus (MRSA), and vancomycin-intermediate resistant S. arureus (VISA). It may be a useful molecule for a new antibiotic development, especially against antibiotic resistant microbe. This substance may play a role in the defense system of this animal against Beauveria bassiana. This is the first report of a peptidyl antimicrobial substance from B. corpus.

• 한국식품영양과학회지
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• 제41권5호
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• pp.714-720
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• 2012

콩 발효식품인 청국장과 된장에서 분리한 $Enterococcus$의 항생제 내성을 평가하고자 31개의 청국장과 17개의 된장으로부터 $Enterococcus$를 분리, 동정한 후 항생제 내성특성을 분석하였다. 모든 청국장 시료에서 119균주, 된장시료에서 4균주, 총 123개의 $Enterococcus$를 분리하였고 가장 많이 분리된 종은 청국장에서는 $E.$ $faecium$ 69균주, $E.$ $faecalis$ 20균주 등이며 된장시료에서 분리한 4균주는 모두 $E.$ $faecium$으로 동정되었다. 총 123개의 $Enterococcus$는 ampicillin, chloramphenicol, penicillin, tetracycline에 내성이 낮게 나타났다. 그리고 erythromycin, ripampin, streptomycin 등에게는 내성이 높은 것으로부터 민감성이 있는 것까지 다양하게 분포하였다. 청국장에서 분리된 $Enterococcus$의 vancomycin MiC 범위는 0.25~8 ${\mu}g/mL$로 나타났으며, MiC 8 ${\mu}g/mL$ 정도의 낮은 내성균 17균주가 $E.$ $faecalis$, $E.$ $faecium$, $E.$ $gallinarum$, $E.$ $casselifalvus$ 등에 고르게 분포되어 있음을 알 수가 있었다. 모든 분리균주에서 고농도 vancomycin 내성유전자인 $van$A, $van$B는 검출되지 않았다. 본 연구의 결과 $Enterococcus$는 자연환경에 널리 분포하고 있는 만큼 가공식품에는 항생제 내성균주와 vancomycin-resistant $Enterococcus$가 존재할 수 있으나 이들 청국장, 된장 등의 콩 발효식품 $Enterococcus$에는 주요 항생제에 내성정도가 높지 않아 항생제 안전성이 있는 것으로 보인다.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.734-741
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• 2009

Recently, strains of methicillin-resistant Staphylococcus aureus (MRSA) with reduced susceptibility to vancomycin (VCM) have been clinically isolated. The antibacterial activity of a new drug, linezolid (LZD), in such a strain was evaluated by measuring bacterial metabolic activity. A total of 73 MRSA strains having various susceptibilities to VCM were subjected to a novel and highly sensitive chemiluminescence-based assay. LZD MIC in the tested strains, measured by the microbroth dilution method, was within the range 1-4 mg/l (mostly ${\leq}2$mg/l), except for one LZD-resistant strain (NRS127; MIC=7 mg/l), and showed no correlation with VCM resistance. The chemiluminescence assay demonstrated that bacterial metabolic activity was strongly suppressed with increasing LZD concentration. The chemiluminescence intensity curve had a low baseline activity without tailing in most strains. The present results suggest that LZD has strong antibacterial activity against MRSA strains, and would be effective for treatment of infections that are poorly responsive to VCM. The chemiluminescence assay facilitated sensitive and discriminative susceptibility testing within a relatively short time.

• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.354-359
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• 2003

Multiplex-PCR protocols were designed in order to make a rapid identification of MRSA. MecA, femB, and 165 rRNA genes were amplified for making a detection of MRSA. The incidence of MRSA in the clinical isolates of Staphylococcus aureus was examined by using a multiplex-PCR assay. The mecA gene was detected in 266 strains out of 336 clinical isolates of S. aureus, thus the incidence of MRSA was approximately 76.5%. The MRSAs of 247 strains (96.1%) showed resistance to more than eight species of the antimicrobial agents tested. The isolates of MRSA showed 27 different antimicrobial-resistant patterns. The results indicate that many different MRSA strains having high multidrug resistance are actually prevalent in Korea. Also, VISA was screened from the MRSA. Two strains were grown on the BHI agar plate supplemented with $8\;\mu\textrm{g}/ml$ of vancomycin at a frequency of $1/10^8$ colony forming units or higher.