• Korean Journal of Veterinary Service
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• v.33 no.3
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• pp.233-240
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• 2010

Methicillin-resistant coagulase-negative staphylococci (MRCNS) were isolated from the respiratory sites of chickens in 4 farms and slaughter house located in Chungnam provinces. Isolation of coagulase-negative staphylococci (CNS) was positive for 61 (26.6%) of the 229 chickens tested, and isolation of MRCNS was positive for 17 (27.9%) of the isolated CNS. A total of 17 MRCNS isolates were selected and subjected to identification. Of the 17 MRCNS isolates selected, 6 were identified as Staphylococcus cohnii, 2 as S. saprophyticus, 3 as S. simulans, 3 as S. lentus, 2 as S. carnosus, and 1 as S. xylosus. The MRCNS isolates were resistant to many beta-lactam antibiotics, and some isolates were also resistant to macrolide and aminoglycoside antibiotics. The mecA gene was detected in some isolates of each MRCNS strains. The mecA-positive isolates were classified into five staphylococcal cassette chromosome mec (SCCmec). SCCmec types I to IV were detected in isolates from chickens.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.516-518
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• 2011

Purpose: The prevalence of antibiotic-resistant Streptococcus pneumoniae meningitis has increased worldwide. There are some reports about postoperative antibiotic-resistant Streptococcus pneumoniae infection after craniofacial surgery, but, there is no report in Korea. We present a report on the treatment of postoperative multidrug-resistant Streptococcus pneumoniae (MRSP) meningitis and sepsis after craniofacial surgery based on our experience. Methods: The patient was a 7-year-old boy with Crouzon's disease who was treated by fronto-orbital bar advancement. Intraoperatively, frontal sinus opening was seen during osteotomy which was covered with forehead galeopericranial flap. MRSP meningitis was diagnosed after the surgery, he was treated with intravenous vancomycin, meropenem, and levofloxacin. Results: The patient was treated successfully after 3 weeks of intravenous antibiotics treatment. During the 8 month follow-up period, there was no neurologic sequelae. Conclusion: Postoperative infection after craniofacial surgery is an important phenomenon that needs immediate recognition. Prevention, early diagnosis, and treatment immediate after onset are important as countermeasures against postoperative drug-resistant bacterial infection. To prevent adverse outcome and reoperation, proper antibiotics treatment should be performed.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.258-265
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• 2009

A study on livestock environment improving agents was conducted; top two brands (A and B) in the market, bottom two brands (E and F) based on market shares and two newly developed agents (C and D) were measured for viable count and tested for resistance towards antibiotics prohibited against livestock feeds. Test results revealed that the measured viable count of agents A and B matched those on the labels were identical; however agent E lacked information on viable counts nor the intended usage, while the measured viable count of agent F was less than the label-stated count. No correlation was found between the antibiotic-resistance test and market share, and most of the agents excluding B were found to display resistance case of Lincosimides such as Lincomycine and Clindmycin, resistant bacteria were found, with the except of agent B. Amoxicillin, Ampicillin and Penillin (type-Penecillins) and Erythromycin (type-Macrolide) were shown to contain resistant bacteria, with the except of agents Band E; the same for Norploxacin (type-Quinoline) and Neomycin antibiotics. Aminoglycosides such as Gentamycin and Streptomycin contained resistant bacteria, excluding agent B. Oxytetracyclin (type-Tetracycline), which is banned for use as resistant bacteria showed the highest sensitivity among the 12 antibiotics, revealed positive results in the test for resistant bacteria; again excluding of agents Band E. These results reveal that many agents contained resistant bacteria despite the fact that they were prohibited; this calls for a more accurate display of the facts and specifications, systematic distributions and strict verification processes of environment improving agents.

• Journal of fish pathology
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• v.34 no.1
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• pp.39-46
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• 2021

Tetracycline (TC) is one of the antibiotics used for treatment of bacterial infection in Korea. Inadequate usage and abuse cause the resistance to antibiotics, like Tetracycline, Erythromycin, and Fluoroquinolone. It can also affect severe economic loss in aquaculture field in Korea. We isolated 101 bacterial samples from diseased fish at aquaculture sites in Gyeonggi-do during 2015~2018. Minimum inhibitory concentration (MIC) method has been used to determine distribution and to identify bacterial isolates resistant to antibiotics including Oxytetracycline (OTC), Ampicillin (AMP), Clindamycin (CLI), Enrofloxacin (ENRO), Gentamycin (GEN). TC resistant isolates were confirmed antibiotic resistant genes by conventional PCR. Bacterial isolates were identified as Aeromonas spp. (43.5%), Pseudomonas spp. (4.0%) and Vibrio spp. (5.0%). It was confirmed that multi-resistant isolates (77.2%) were predominant over single-resistant one (22.8%). TC resistant genes like tet(A), tet(D), tet(E), tet(G), tet(M), and tet(S) were detected and tet(A) was the most prevalent. Aeromonas spp. is a dominant strain in bacterial infections in fishes of aquaculture sites, and further investigation on various antibiotic resistance genes will be needed for clear understanding of aquaculture sites in Gyeonggi-do.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.441-445
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• 1993

Ten bacteriocin-producing Enterococcus faecium strains with urease activity ($1.10-6.2nkat.mL^{-1}$) were isolated from the rumen of 2-8 weeks old calves. All strains were resistant aginst disodium arsenate at a minimal inhibition concentration - MIC $5g.L^{-1}$ and mercury chloride ($MIC=10-20mg.L^{-1}$). Eight strains were resistant against silver nitrate ($MIC=40-50mg.L^{-1}$) and three against antibiotics used. The resistance against six antibiotics was found in A23 strain. Values of adherence index ranged from 5.02 to 20.4 enterococci adhered per one epithelial cell of rumen wall. All isolates produced bacteriocins which inhibited the growth at least of one of five indicator organisms. The EF1 strain with a good affinity to the epithelial cell ($15.2{\pm}1.2$) produced bacteriocin substance with antimicrobial activity against grampositive and gramnegative indicator bacteria.

• Microbiology and Biotechnology Letters
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• v.34 no.1
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• pp.74-77
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• 2006

A lactic acid bacterial strain resistant to several antibiotics such as oxytetracycline, tylosin, neomycin and sulfathiazole, which have been often used as a therapeutic agent in livestock, was isolated from the porcine gastrointestinal tract. The isolate YB-55 was identified as belonging to the genus Pediococcus with the highest similarity to P. pentosaceus on the basis of its 16S rRNA sequence and biochemical properties. The isolated strain showed viability of over 85% at pH 3.0 and was resistant to bile salt. The strain produced lactic acid of 12.3 g/L by jar fermentation and maintained its viability in the presence of antibiotics at dosage related therapeutic effect, suggesting P. pentosaceus YB-55 may of ffr potential as a probiotics for livestock.

• YAKHAK HOEJI
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• v.29 no.3
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• pp.159-164
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• 1985

To investigate the susceptibility and resistance in case of simultaneous administrations of Lactobacilli and Clostridia prekparations with antituberculosis agents and antibiotics, five strains of Lactobacilli, i.e., Lactobacillus bulgaricus, L. casei, L. helveticus, L. acidophilus, L. sporogenes, and Clostridium butyricum were isolated from commercially available preparation. Minimal inhibitory concentrations (MIC) of nine antituberculosis agents and 21 antibiotics against these strains were determined. The results shwoed that these strains were very sensitive only to rifampicin among antituberculosis agents, and sensitive to other antibiotics. Since the simultaneous oral administration of rifampicin and other antibkiotics with these sensitive strains is ineffective, development of new resistant mutants is desirable.

• The Journal of the Korean dental association
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• v.41 no.2 s.405
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• pp.116-123
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• 2003

Antimicrobial Peptides are natural antibiotics evolved by many plants, invertebrate, and vertebrate to defend against the microbial infection. Antimicrobial peptides show a broad-spectrum antimicrobial activity with little opportunity for the development of resistance since they target microbial membranes that distinguish microbes from enkaryotic cells. The oral cavity is constantly exposed to microbial challenges and antimicrobial peptides play an important role in managing the oral health. With the increase of resistant micro-organisms to conventional antibiotics, antimicrobial peptides are attracting interests as novel antibiotics. In this review, the characteristics of antimicrobial of antimicrobial peptides including the classification, mechanism of action, resistance, and expression in the oral cavity have been discussed in the prospects of application to oral disease.

• YAKHAK HOEJI
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• v.35 no.2
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• pp.61-72
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• 1991

These studies were made to assess the present stage of resistance to antibiotics, incidence and transferability of R-factors against E. coli. From March to July 1987, 59 strains of E. coli were isolated from specimens of patients collected at university hospitals in Seoul, 64 strains from stools of domestic animals and 66 strains from drainages in Seoul. These specimens were tested for resistance to 12 kinds of antimicrobial agents by means of agar dilution method. Using Muller-Hinton agar for the assay of drug resistance and tryptic soy broth as propagating medium for conjugation. The strains of E. coli were found to be resistant to one or more antibiotics and were considered to be potential donors of R-plasmid. The resistant strains of E. coli isolated from patients, domestic animals and drainages were found to be 55(93%), 33(52%) and 31(47%), respectively. Resistance to Tc, Ap and Cb was the highest in those isolated from patients and drainages, and resistance to Tc, Cm and Sm was the highest in those isolated from domestic animals. In the transfer test of drug resistance by conjugation method, 17 strains (47%) isolated from patients, 15(54%) isolated from domestic animals and 15(56%) isolated from drainages showed positive results, transperable resistant plasmid molecules with variable range in each strain.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1263-1272
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• 2009

Danshen (Salvia miltiorrhiza Bunge) is a traditional Korean medicine that is commonly used for the treatment of inflammatory diseases such as edema, arthritis, hepatitis, and endangitis. The several extracts of danshen were tested for antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) isolated in clinic by broth microdilution method, the checkerboard, and time-kill methods to evaluate the synergistic effects of the combination of the extracts with antibiotics. The chloroform ($CHCl_3$) and n-hexane (HEX) extracts [minimum inhibitory concentration (MIC), 0.0078-0.3125${\mu}g/mL$; minimum bactericidal concentration (MBC), 0.019-0.625${\mu}g/mL$] were found to have strong antibacterial activity against MRSA. Additionally, when the $CHCl_3$ and HEX extracts were co-administered with ampicillin or oxacillin, a synergistic effect against MRSA was observed. Furthermore, a time-kill study evaluating the effects of the extracts against MRSA indicated that treatment with the $CHCl_3$ extract in combination with ampicillin or oxacillin produced rapid bactericidal activity. These results suggest that danshen extracts may have potently antimicrobial activity and thus, it can be a suitable phytotherapeutic agent for treating MRSA infections.