• Journal of Veterinary Clinics
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• v.28 no.4
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• pp.348-351
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• 2011

The purpose of this study was to determine the distribution of gram-negative bacteria isolated from companion animals with sepsis, and to investigate the antimicrobial susceptibility patterns of the isolates. Bacterial pathogens were isolated from specimens of dogs and cats submitted to National Veterinary Research and Quarantine Service between 2008 and 2009. A total of 44 gram-negative pathogens were isolated from necropsied organs. The most common isolates were E. coli (n = 33), K. pneumoniae (n = 4) and B. bronchiseptica (n = 4). Most of gram-negative isolates were susceptible to ceftiofur (68.2%), colistin (84.1%), florfenicol (84.1%) and spectinomycin (61.4%). Most of those were resistant to ampicillin (77.3%), erythromycin (86.4%), flumequine (65.9%), lincomycin (97.7%), oxytetracycline (61.4%), penicillin (100%), streptomycin (63.6%), spiramycin (97.7%), sulfamethoxazole (90.9%), tylosin (97.7%) and tiamulin (100%). In conclusion, colistin and florfenicol could be useful against sepsis due to gram-negative bacteria.

• Korean Journal of Veterinary Research
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• v.19 no.2
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• pp.121-126
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• 1979

대장균 설사중에 걸린 어린 돼지, 송아지, 어린 양에서 분리한 대장균 126주의 항생제와 화학요법제(15종)에 대한 감수성을 disc diffusion technique로 조사한 성적은 다음과 같다. 1. 어린 돼지에서 분리한 62주의 대장균은 gentamicin(GM)에 100%, colistin(CL)에 96.8%, kanamycin(KM)에 93.5%, neomycin(NM)에는 91.9%가 감수성을 가지고 있었으나 ampicillin(AM), erythromycin(EM), lincomycin (LM), novobiocin (NB), penicillin (PC), streptomycin(SM), tetracycline(TC), sulfaisodimidin(SU)에는 내성을 가지고 있었다. chloramphenicol(CP), sulfamethoxazole-trimethoprim(SXT), cephalosporin(CE)에는 각각 75.8%, 64.5%, 50%가 감수성이 있었다. 2. 송아지에서 분리한 32주의 대장균은 GM에 100%, CL에는 87.5%, SXT에는 66.7%가 감수성이 있었으나 CP와 KM에는 각각 40.6%, SU에는 56.2% NM에는 62.5%, SM에는 87.5%가 내성을 가지고 있었다. EM, LM, NB, PC에는 전혀 감수성이 없었으며 AM, SM, TC에도 고도의 내성을 가지고 있었다. 3. 어린 양에서 분리한 32주의 대장균은 GM과CL에 100%, CP에 96.9%, KM과 NM에 90.6%가 감수성이 있었다. SM과 SU에도 71.9%나 감수성이 있었으나 CM, EM, LM, PC, TC에는 대부분 내성을 가지고 있었다. AM에는 21.9%가 감수성이 있었다. 4. 2종류 이상의 약제에 내성을 가진 대장균의 AM, CE, CP, CL, GM, KM, NM. SM, TC, SU등 10종의 약제에 대한 multiple drug resistance pattern(MDRP)을 조사한 바 돼지 유래 약제내성 대장균의 MDRP는 18가지였으며 이중 가장 빈도가 높은 것은 AM, CE, SM, TC, SU 내성형으로 전체의 24.2%나 되었다. 송아지 유래 약제내성 대장균의 MDRP는 17가지였으며, AM, CE, CP, KM, NM, SM, TC, SU 내성형이 28.1%로 가장 빈도가 높았다. 반면에 어린 양에서 분리한 대장균의 MDRP는 9가지였으며 AM, CE, SU의 3약제 내성형이 40.6%로 가장 많았다.

• Journal of Environmental Health Sciences
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• v.39 no.5
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• pp.447-455
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• 2013

Objectives: This study aims to understand the concentration, diversity, and antibiotic characteristics of staphylococci present in the indoor air of child-care facilities. Methods: Air sampling was performed from October 2012 to January 2013 in 120 child-care facilities in Seoul, Korea. Methicillin-resistant bacteria were selected from the total obtained airborne bacteria and subjected to 16S rRNA analysis for methicillin-resistant staphylococcal species determination. Identified staphylococcal strains were tested for resistance to a range of antibiotics. Results: Average total airborne bacterial concentration was $508.9{\pm}246.3CFU/m^3$. Indoor concentration of total airborne bacteria had a significant positive correlation with the $CO_2$ concentration in the child-care facilities. Methicillin-resistant staphylococci were present in 13.3% of the child-care facilities studied. A total of four species (S. epidermidis, S. cohnii, S. saprophyticus, S. sp.) and 55 strains were identified from the indoor air of the child-care facilities. Staphylococcus cohnii was the most common species (54.5%), followed by S. epidermidis (38.2%). All of the isolated staphylococcal strains exhibited high resistance to oxacillin, erythromycin, mupirocin, and ceftizoxime. Especially, S. saprophyticus strains showed more multidrug resistance to oxacillin, vancomycin, clindamycin, erythromycin, lincomycin, ceftizoxime, mupirocin, and tetracycline than did other species. Conclusion: The results of this study showed that a monitoring system for multidrug-resistant bacteria is needed in facilities for children, as the community-associated infections of these bacteria are increasing.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.19-28
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• 2000

There are several main antibacterial susceptibility tests, such as agar dilution method, broth dilution method and disk diffusion technique. Especially, for minimal inhibitory concentration (MIC) test, agar dilution method has been widely used. But that method is so complicated and bothering that it's difficult to treat a large amount of strains. On the other hand, modified broth dilution method(add 1% glucose and 0.018% phenol red as a pH indicator to broth) is fast and easy to perform. Most of all, it can visualize the result by color. The MICs of 22 antibiotics Including penicillins, aminoglycosides, cephalothin, chloramphenicol, lincomycin, ceftiofur, vancomycin and quinolones, erythromycin, colistin. sul-fadimethoxine, trimethoprim for arcanobacterium pyogenes 14 strains, actinobacillus pleuropneu-moniae 41 strains and pasteurella multocida 37 strains, which were collected from porcine during 1996 ∼ 1999, were determined by modified broth dilution method. Actinobacillus pleuropneumoniae was highly susceptible to all kinds of quinolones such as ciprofloxacin, enrofloxacin and norfloxacin and to all aminoglycosides, like gentamicin, apramycin, kanamycin and ampicillin, cephalothin and ceftiofur. But It was quite resistant to solfadimethoxin, colistin and vancomycin. Pasteurella multocida was found to have high susceptibility to ampicillin, cephalothin, chlorampenicol and gentamicin but had mid-degree susceptibility to other aminoglycosides. In addition, it was susceptible to norfloxacin and nalidixic acid, but not to newer fluoroquinolone like ciprofloxacin and enrofloxacin and it was resistant to colistin and kanamycin. Arcanobacterium pyogenes was highly susceptible to most of quinolones such as cipoofloxacin, enrofloxacin and norfloxacin and gentamicin and penicillin G. But it also obtained high resistance against the early quinolone, nalidixic acid and aminoglycosides such as amikacin, apramycin and kanamycin and erythromycin, chlorampenicol, tetracyclin and vancomycin.

• Journal of Photoscience
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• v.8 no.1
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• pp.1-7
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• 2001

The deteriorative effect of ultraviolet-B(UV-B) radiation on photosynthesis was assessed by the simultaneous measurement of O$_2$ evolution and chlorophyll(Chl) fluorescence in green pepper. UV-B was given at the intensity of 1 W$.$m$\^$-2/, a dosage often encountered in urban area of Seoul in Korea, to detached leaves. Both Pmax and quantum yield of O$_2$ evolution was rapidly decreased, in a parallel phase, with increasing time of UV-B treatment. Chl fluorescence parameters were also significantly affected. Fo was increased while both Fm and Fv were decreased. Photochemical efficiency of PSII(Fv/Fm) was also declined, although to a lesser extent than Pmax. Both qP and NPQ were decreased similarly with increasing time of UV-B treatment. However, PS I remained stable. The addition of lincomycin prior to UV-B treatment accelerated the decline in Fv/Fm to some extent, suggesting that D1 protein turnover may play a role in overcoming the harmful effect of UV-B. The amount of photosynthetic pigments was less affected than photosynthetic response in showing decline in Chl a and carotenoids after 24 h-treatment. Presumptive flavonoid contents, measured by changes in absorbance at 270 nm , 300 nm and 330nm, were all increased by roughly 50% after 8 h-treatment. Among antioxidant enzymes, activities of catalase and peroxidase were steadily increased until 12h of UV-B treatment whereas ascorbate perxidase, dehydroascorvate reductase and glutathione reductase did not show any significant change. The results indicate that deteriorative effect of UV-B on photosynthesis precedes the protection exerted by pigment synthesis and antioxidant enzymes.

• Environmental Engineering Research
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• v.25 no.4
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• pp.614-621
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• 2020

Antibiotic pollution is one of the factors contributing to the spread of antibiotic-resistant bacteria in the environment. Advanced oxidation and irradiation processes have been introduced to eliminate antibiotics from water and wastewater. However, few studies have reported the toxic effects of residual antibiotics and their byproducts induced by a treatment system. In this study, we compared the efficacies of chemical (high-performance liquid chromatography (HPLC)) and biological (antimicrobial susceptibility test) assays for measuring the concentrations of residual antibiotics after gamma irradiation for degrading amoxicillin, cephradine, lincomycin, and tetracycline. The concentrations of residual antibiotics estimated using the two assay methods were almost identical, except cephradine. In the case of cephradine, inhibited bacterial growth was observed that was equivalent to twice the concentration measured by HPLC in the samples subjected to gamma irradiation. The observed inhibition of bacterial growth suggested the generation of potentially toxic intermediates following antibiotic degradation. These results indicate that biological and chemical assays should be used in concert for monitoring antibiotic contamination and the toxic derivatives of antibiotic degradation. The results demonstrate that these four antibiotics can be decomposed by 2.0 kGy gamma-irradiation without toxic effects of their byproducts.

• Microbiology and Biotechnology Letters
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• v.14 no.3
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• pp.265-270
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• 1986

The best conditions for the protoplast fusion of Lactobacillus casei have been searched for in this study. Antibiotic resistance was used as the selective marker for enumerating and selecting the recombinants. Antibiotic resistant mutants were isolated after treating cells with N-methyl-N'-nitro-N'-nitrosoguanidine. High frequency fusion of protoplasts of L. casei strains were obtained in the presence of 40% (wt/vol) polyethylene glycol 4,000 after 1 min at 3$0^{\circ}C$ at around neutral pH. Spontaneous mutations of drug-resistance of L. casei were two or three orders lower than the recombination frequency. Recombination frequencies were about 10$^{-4}$ per parent cells employed.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.395-398
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• 2007

A total of 114 Salmonella spp. (17.90%) were isolated from 637 fecal swab samples collected in October 2005 and they were from 25 (78.13%) of 32 farms investigated nation-widely in Korea. Salmonella spp. from age group of 30-, 60-, 90-, 120-day olds were 17.61%, 16.98%, 15.72%, and 21.25%, respectively. Nine serovars of Salmonella spp. were identified. The predominant serovars of isolates were S. Typhimurium (including var Copenhagen), S. Agona, S. Derby, and S. Heidelberg by turns. Almost isolates belonged to serogroup B (69.30%). All isolates were resistant to penicillin G and oxytetracycline, and this was considered due to be used as feed additive through the most of pig farms for decades. And also, frequent resistance observed for ampicillin, sulfamethoxazole-trimethoprim, and lincomycin-spectinomycin, which are commonly used in veterinary medicine for decades, indicates an urgent need to utilize these antimicrobials more prudently if their benefits are to be preserved.

• The Journal of the Korean Society for Microbiology
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• v.21 no.1
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• pp.97-106
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• 1986

Authors studies on the isolation of V. vulnificus from sea water, sea mud fishes, shellfishes and algae at the seasides of Pusan, Masan, Chungmu and Ulsan in Korea in 1985. Authors carried out test for isolated strains to bacteriological test, hemolysis test about erythrocytes of various animal, sensitivity test of various chemotherapeutic agents and serological test with antiserum of V. vulnificus. The resultls obtained were as follows: 1. V. vulnificus was isolated 15 strains from 399 total specimens: 110 cases of sea water, 40 cases of sea mud, 90 cases of fishes, 60 cases of shellfishes and 79 cases of various algae, respectively. 2. Nine strains were isolalted from sea water, 4 strains were isolated from sea mud and 2 strains were isolated from fishes, respectively. 3. Two strains among 15 strains isolated were lactose positive reaction. 4. All strains isolated were grown in concentration of $0.5%{\sim}7.0%$ NaCl, but were not grown 0% and 8.0% NaCl. 5. Hemolysis reaction about various erythrocytes was sensitived to guinea pig, human and rabbit erythrocytes, but was not sensitived to sheep erythrocytes. 6. Sensitivity test using with chemotherapeutic agents of "BioLab" Microbial Sensitivity Test Discs were generally sensitived to amikacin, ampicillin, clindamycin, erythromycin, gentamycin, kanamycin, streptomycin, tetracyclin and tobramycin, and were moderate to penicillin, but were resistant to methicillin and lincomycin, respectively. 7. The distribution of serotypes of V. vulnificus isolated were on antiserum of $0.1{\sim}07$ of V. vulnificus: 1 case of 01 and 2 cases of 07, respectively.

• Korean Journal of Environmental Agriculture
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• v.25 no.2
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• pp.109-117
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• 2006

Photoinhibition and photoprotection of PSII in the leaves of hot pepper (Capsicum annuum L.) grown in Hoagland solution and Tap water were compared. Though changes in the rates of $O_2$ evolution as a function of photon fluence rate (PFR) were comparable, the rates of respiration in the dark was 3 times higher in the Hoagland solution grown leaves than in the Tap-water grown ones. Compared to Hoagland solution grown plane, PSIIs of Tap water grown pepper leaves were more susceptible to photoinhibitory light treatment. In order to inactivate functional PSII to the same extents, Hoagland solution grown plants required almost 2-fold high light $(1600{\mu}molm^{-2}s^-)$ treatment than those of Tap water $(900{\mu}molm^{-2}s^-)$. Interestingly, the remaining fraction of PSII in Hoagland grown pepper was able to survive under prolonged illumination in the presence of lincomycin, which probably means that the growth condition of plant seemed to have an effect on the recovery of PSII from light stress. When PSII was severly photoinactivated at a chilling temperature, recovery was observed only if the residual functional PSII were not inhibited with DCMU, Nigericin and MV during recovery. In conclusion, PSIIs grown in the Hoagland solution was more resistant to excess light than in the Tap water grown one and the recovery of PSII from photodamage was more efficient in Hoagland grown pepper leaves than Tap water grown one, which means that the increased dark respiration may play a important role in the protection of PSII from photoinhibition by helping repair photosynthetic proteins (in particular, the D1 protein of PSII) degraded by photoinhibition.