• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.267-271
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• 1998

Cotyledon explants of lettuce were cocultured with Agrobacterium tumefaciens LBA4404::pBKS-GR1 harboring glutathione reductase(GR) gene in MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip for 48 hr. These explants were transferred to MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip, 50 mg/L kanamycin, and 500 mg/L carbenicillin. After 4 weeks of subculture, kanamycin-resistant shoots were obtained on selection medium. Leaves of putative transformants survived on selection medium containing 100 mg/L kanamycin. Incoporation of the GR gene into lettuce was confirmed by PCR analysis of genomic DNA. Southern blot analysis showed that ECL-labeled GR gene was hybridized to the expected amplified genomic DNA fragment of about 1.8 kb from transgenic lettuce. The presence of mRNA in transgenic lettuce was confirmed by RT-PCR with total RNA of transgenic lettuce. In progeny test of transformants, R$_1$ seeds were resistant to kanamycin (200mg/L) on MS medium.

• Journal of Life Science
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• v.9 no.5
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• pp.564-569
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• 1999

This study was conducted to determine the concentrations of plant growth regulators required for regeneration and the concentrations of antibiotics for the selection of transformed regenerants from lettuce, musk melon and tomato. The optimal concentrations of plant growth regulators for shoot formation were NAA 0.1 mg/$\ell$ +BA 0.1 mg/$\ell$ for lettuce, NAA 0.01 mg/$\ell$ +BA 2.0 mg/$\ell$ for melon and NAA 0.1 mg/$\ell$ +BA 0.5 mg/$\ell$for musk melon. Shoot induction from tomato, lettuce and melon was completely inhibited by 30 mg/$\ell$ or higher concentrations of kanamycin. Shoot formation from mu나 melon was not affected by kanamycin up to 40 mg/$\ell$, but was reduced in the presence of 50 mg/$\ell$ and completely inhibited by 100 mg/$\ell$. Shoot formation of all four crops was completely inhibited by higromycin at 10 mg/$\ell$. Both carbenicillin and cefatoxinme did not show any negative effects on shoot formation.

• Korean Journal of Plant Tissue Culture
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• v.28 no.4
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• pp.197-200
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• 2001

Agrobacterium tumefaciens MP90 harboring PAT (phosphinothricin acetyltransferase) and NPTII-GUS gene were used for the genetic transformation of lettuce (Lactuca Sativa L.). Shoot regeneration from cotyledon explants were obtained from the MS medium supplemented with 0.1 mg.L$^{-1}$ NAA, 1.0 mg.L$^{-1}$ 2ip, 50 mg.L$^{-1}$ kanamycin and 500 mg.L$^{-1}$ carbenicillin after cocultivation with A. tumefaciens for 2 days. Kanamycin resistance test of transgenic plants indicated that the NPTII gene was integrated into the lettuce genome and was stably expressed. PCR and northern blot analysis indicated that bialaphos resistance gene (PAT) was stably integrated into the lettuce genome. The transgenic plant sprayed with Basta (1500x) remained healthy with continuous growth, while the control group exhibited fatality.

• Korean Journal of Veterinary Research
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• v.49 no.2
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• pp.113-119
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• 2009

Atrophic rhinitis (AR) is the one of important respiratory diseases and causes severe economic losses in pig industry. Severe attempts have been made to reduce the economic losses by preventing the disease. One of the methods is the spraying of antibiotics into nasal cavity of piglets. Recently, the efficacy of the spraying with kanamycin and gentamicin was reduced in the Korean swine industry. Therefore, the preventive methods have been required to be changed based on the antimicrobial susceptibility profiles of causative agents of swine AR. Based on the current situations of this disease, Bordetella (B.) bronchiseptica and Pasteurella (P.) multocida 4D were isolated from pigs with clinical signs of AR. The isolation rates of B. bronchiseptica and P. multocida 4D were 58.5% and 32.9%, respectively. In the antimicrobial susceptibility test, the bacteria were resistant to kanamycin and gentamicin which have been used as the spraying agents, but they were susceptible to amikacin. A new spraying agent was developed using amikacin using ${\beta}$-glucan and yakbaltag as supplementary agents. Field efficacy of the agent was carried out with different schedule. The results from this study suggested that the newly developed spraying agents might be helpful to prevent AR in swine.

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.95-98
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• 1998

Hypocotyl explants of flowering cabbage were cocultured with Agrobacterium tumefaciens LBA4404;;pGA875 harboring proteinase inhibitor II(PI-II) cDNA and then regenerated into plants. Sucessful transcripts of PI-II gene were detected by RNA dot blot analysis. Bioassay was conducted on transgenic flowering cabbage. It was confirmed that insecticidal activities of transformants were much higer than that of control plants. In progeny test of hansformants, 27.4% of T$_1$ seeds was resistant on MS medium containing 20 mg/L kanamycin.

• The Journal of the Korean Society for Microbiology
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• v.13 no.1
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• pp.43-48
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• 1978

The difference in antimicrobial susceptibility of multiply drug-resistant Salmonella typhi by the methods of test was tested against chloramphenicol(Cm), tetracycline(Tc), ampicillin(Ap), kanamycin(Km), and rifampicin(Rif), and the results were compared by the minimum inhibitory concentration(MIC). No appreciable difference was noted between MICs of Cm, Tc, and Rif measured by agar plate dilution(plate) method and broth dilution(broth) method. However, MICs of Km to about a half of test strains were 4 to 8-fold higher by broth method than plate method, and MICs of Ap by broth method were also a little higher than plate method in some strains. Cm and Rif were bacteriostatic rather than bactericidal to the most of test strains in high concentrations. Tc, Ap and Km were exclusively bactericidal to the test strains.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.163-169
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• 1999

This study was conducted to produce herbicide resistant plants by transferring phosphinothricin acetyltransferase (PAT) gene into Populus alba $\times$ Populus glandulosa No .3 using Agrobacterium tumefaciens MP 90/PAT. Leaf segments from in vitro grown shoots of hybrid poplar No. 3 were soaked in a AB medium containing Agrobacterium tumefaciens MP 90/PAT for 10 min and cocultivated for 2 days on MS medium containing 1.0 mg/L 2,4-D and 0.2mg/L kinetin (CIM). Putative transformed calli could be selected after cocultivation of leaf segments on CIM supplemented with 50mg/L kanamycin and 500mg/L cefotaxime for 3 weeks. The selected calli were cultured on CIM supplemented with 50 mg/L kanamycin and 500 mg/L cefotaxime for 5~8 weeks before transfer to WPM containing 1.0mg/L zeatin, 0.1mg/L BAP, 50 mg/L kanamycin and 500mg/L cefotaxime for shoot regeneration. Shoots were regenerated from the callus after 4 week cultivation, and the regenerants were grown on the same medium for 7~l0 weeks. The plants rooted on 1/2 WPM containing 0.2 mg/L IBA and 50 mg/L kanamycin. To confirm the gene insertion into plants, GUS activity was detected by histochemical assay in the transformed plants. Finally, the presence of both NPT II and PAT genes from the transgenic plants were confirmed by PCR amplification with the gene specific primers and subsequent PCR-Southern blot with DIG-labeled PAT gene probe. After acclimatization in pots for 4 weeks, the plants were sprayed by 3 mL/L of Basta to test resistance to the herbicide. The transgenic plants remained green, whereas all the control plants died after one week.

• Korean Journal of Veterinary Research
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• v.27 no.1
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• pp.61-68
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• 1987

This study was conducted to determine the microorganisms inhabitating in cow genitalia and their antimicrobial drug susceptibility. During the period between July, 1985 and February, 1986, a total of 111 cow genitalia, 58 from Korean native and 53 from dairy cow, were sampled at three abattoirs. Gross pathological examination and bacterial isolation and identification were performed from the genital samples. In addition antimicrobial drug susceptibility test for the microorganisms isolated, some synergistic activity among drugs were examined on the major organism isolated from the cases of endometritis and pyometra. The results are summerized as follows: 1. Among the bacteria isolated from the genitalia, Staphylococcus spp., C. pyogenes, E. coli, Proteus spp., Streptococcus spp., Bacillus spp. were most frequently isolated whereas the genera of Pasteurella, Pseudomonas, Klebsiella and Yersina were detected far less frequently. 2. In Korean native cow the genera of Straphylococcus and Steptococcus were more isolated than dairy cow while in dairy cow the genera of Corynebacterium, Proteus, Escherichia were more of ten isolated than Korean native cow. 3. From cow genital organs showing lesions of endometritis and prometra, C. pyogenes was most frequently isolated, the isolation rate being 60 percent, and follow by Staphylococcus spp., Proteus spp., E. coli and Pasteurella spp. in the order. 4. Antimicrobial drug susceptibility test conducted on the major organisms isolated showed that all the isolates were susceptible to gentamicin, cephalosporin and sulfisoxazole, but resistant to tetracycline and penicillin. 5. Twenty-nine isolates of C. pyogenes were submitted to the synergistic activity test of cephalosporin, kanamycin and streptomycin with penicillin. Synergists were demonstrated in 90 percent, 31 percent and 27 percent of isolates examined by the combined use of penicillin and cephalosporin, penicillin and kanamycin, penicillin and streptomycin, respectively. About 10 percent of the isolates were found to be indifferent by the synergism test.

• 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 Veterinary Clinics
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• v.1 no.1
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• pp.41-47
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• 1984

The author carried out bovine mastitis test by California Mastitis test(CMT) for the milk from dairy cows in the surburbs of Taejeon. In order to select prefer commercial therapeutic antibacterial agents for mastitis treatment, Staphylococcus aureus were isolated from the CMT positive milk and the strains were tested for the tolerance test to the agents. The results obtained were summarized as follows : 1. The tolerance test appeared graduate tolerance in cases with continuously repeat of therapeutic agents. 2. The antibacterial agents revealed strong tolerance were D-and E-ointments. 3. The antibacterial agents revealed suspect tolerance were A-and F-ointments and ampicillin, penicillin, kanamycin and streptomycin. 4. The antibacterial agents revealed non or rare tolerance were B-and G-ointments and chloramphenicol, erythromycin and oxytetracycline. 5, It is concluded that the use of 3-day-interval in turn with antibacterial agents selected by tolerance test may be beneficial.