• YAKHAK HOEJI
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• v.50 no.3
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• pp.199-203
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• 2006

A new type of macrolides, lincosamides and streptogramin B antibiotics (MLS) resistance, showing the characteristic phenotype growing within the inhibition zone area around the clindamycin disk, was identified among clinically isolated Staphylococcus aureus. We named the phenotype as MLS resistance with foggy-D shape (fMLS). The average frequency of MLS isolates was 9%. All of fMLS isolates have only erm(A) for the resistance determinant. The growth pattern of the challenged MLS isolate looks intermediate phase between the patterns of inducible MLS resistance and constitutive MLS resistance.

• Economic and Environmental Geology
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• v.48 no.3
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• pp.241-246
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• 2015

Helicobacter pylori is an important transmissible human pathogen found on the luminal surface of the gastric epithelium. The organism can persist in the stomach indefinitely and causes gastroduodenal inflammation that may proceed to atrophic gastritis, peptic ulcer, gastric MALT lymphoma, and gastric cancer. Standard triple therapy which consists of proton pump inhibitor (PPI) plus two antibiotics (amoxicillin and clarithromycin) is now generally used in Korea, however, eradication rates of H. pylori has been decreasing due to increasing antibiotic resistance. In this review, current second-line treatment regimens, difficult problems on treatment, necessity of local target therapy, applicability of clay minerals as a drug delivery system (DDS), and a new therapeutic strategy and its study plans will be discussed.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.390-395
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• 2011

Fusarium wilt caused by Fusarium oxysporum has become a serious problem world-wide and relies heavily on chemical fungicides. We selected Pseudomonas sp. NJ134 to develop an effective biocontrol strategy. This strain shows strong antagonistic activity against F. oxysporum. Biochemical analyses of ethyl-acetate extracts of NJ134 culture filtrates showed that 2,4-diacetylphloroglucinol (DAPG) was the major compound inhibiting in vitro growth of F. oxysporum. DAPG production was greatly enhanced in the NJ134 strain by adding mannitol to the growth media, and in vitro antagonistic activity against F. oxysporum increased. Bioformulations developed from growth of NJ134 in sterile bean media with mannitol as the carbon source under plastic bags resulted in effective biocontrol efficacy against Fusarium wilt. The efficacy of the bioformulated product depended on the carbon source and dose. Mannitol amendment in the bean-based formulation showed strong effective biocontrol against tomato Fusarium wilt through increased DAPG levels and a higher cell density compared to that in a glucose-amended formulation. These results suggest that this bioformulated product could be a new effective biocontrol system to control Fusarium wilt in the field.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.89-89
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• 2003

본 연구는 난소의 황체를 체외배양시 TGF-$\beta$1의 황체내 발현을 조사하기 위해 수행되었다. 돼지 황체는 축산기술연구소에서 사육중인 돼지(체중 145$\pm$kg) 12두로부터 발정을 유도시켜 배란 후 약 48시간째 도축하여 난소를 회수하였다. 회수된 난소로부터 황체를 분리하여 세절한 후 0.25% collagenase용액(0.025mg DNase, 50mM EDTA, 50mM Dithio-threitol)으로 37$^{\circ}C$의 진탕 수조에서 30분간 배양하여 황체세포를 분리 회수하였다. 회수된 황체세포는 D-MEM용액(GIBCO, 10% FCS와 antibiotics 첨가)으로 2회 세척하여 1$\times$$10^{6}$live cell/$m\ell$이 되도록 희석하여 24 well culture plate(Corning, New Tork 14831)에 분주하여 $CO_2$ 배양기($CO_2$: 5%)에서 24시간 간격으로 2회 배양액을 교환해 48시간 동안 배양하였다. 배양된 황체 세포는 immunocytochemistry 방법으로 TGF-$\beta$1의 발현을 관찰함과 동시에 황체조직도 같은 방법을 사용하여 TGF-$\beta$1 의 발현 유ㆍ무을 관찰하였다. 그 결과 황체세포 그리고 황체 조직 뚜렷한 TGF$\beta$1의 발현을 확인할 수 있었다. 이 결과로서 TGF$\beta$1은 황체기능을 유지하는데 하나의 인자로서 작용하며 다른 인자들과의 상호작용을 시사하고 있다.

• Journal of Animal Science and Technology
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• v.57 no.1
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• pp.2.1-2.5
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• 2015

Among the main intimidation to the sheep and goat population, PPR outbreaks are causing huge losses especially in endemic areas. During recent times, six outbreaks of PPR were confirmed at semi-organized goat farms/herds in various regions of Punjab province and Islamabad capital territory (ICT), Pakistan. The disease started after introduction of new animals at these farms with no history of previous PPR vaccination. The clinical signs appeared affecting respiratory and enteric systems and spread quickly. Disease caused mortality of 10-20% and morbidity of 20-40% within a time period of four weeks. Morbidity and mortality rates were 30.38% (86/283) and 15.55% (44/283), respectively. Three treatment regimes were executed to demonstrate the role of vaccination during outbreak at these farms. First was to use only the broad spectrum antibiotics (Penicillin & Streptomycin and/or Trimethoprim and Sulfadiazine) at two farms (Texilla and Attock). Second treatment regime was to use the same broad spectrum antibiotic along with extensive fluid therapy (Farms at ICT-1 and ICT-2). The third regime was to use of broad spectrum antibiotic plus fluid therapy along with vaccinating the herd against PPR during first week of outbreak (ICT-3 and ICT-4). The third scheme of treatment gave the better results as there was no mortality in third week post-outbreak. Therefore, it is suggested to give proper importance to PPR vaccination along with conventional symptomatic treatment when dealing the PPR outbreaks in endemic disease conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.885-893
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• 2001

This review summarizes some recent research into ways of improving the productivity of ruminal fermentation by increasing protein flow from the rumen and decreasing the breakdown of protein that results from the action of ruminal microorganisms. Proteinases derived from the plant seem to be of importance to the overall process of proteolysis in grazing animals. Thus, altering the expression of proteinases in grasses may be a way of improving their nutritive value for ruminants. Inhibiting rumen microbial activity in ammonia formation remains an important objective: new ways of inhibiting peptide and amino acid breakdown are described. Rumen protozoa cause much of the bacterial protein turnover which occurs in the rumen. The major impact of defaunation on N recycling in the sheep rumen is described. Alternatively, if the efficiency of microbial protein synthesis can be increased by judicious addition of certain individual amino acids, protein flow from ruminal fermentation may be increased. Proline may be a key amino acid for non-cellulolytic bacteria, while phenylalanine is important for cellulolytic species. Inhibiting rumen wall tissue breakdown appears to be an important mechanism by which the antibiotic, flavomycin, improves N retention in ruminants. A role for Fusobacterium necrophorum seems likely, and alternative methods for its regulation are required, since growth-promoting antibiotics will soon be banned in many countries.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.397-401
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• 1997

The present research program was conducted to characterize a strain of actinomycetes producing an anti methicillin-resistant Staphylococcus aureus (MRSA) antibiotic. Soil samples were collected from various sites in Korea and a number of actinomycetes were isolated from the soil samples by applying selective agar for actinomycetes. Among over 400 isolates, a strain (AMLK-135) producing anti-MRSA antibiotic against S. aureus TK 784 was selected. According to the morphological and physiological characteristics, the strain AMLK-135 was confirmed to belong to the genus Streptomyces. From the results of species identification with the TAXON program, the strain AMLK-135 was shown to belong to major cluster 5 (Streptomyces exfoliatus), but it had a low simple matching coefficient ($S_{SM}$ SM/) value to member organisms of major cluster 5. Percentage ($\%$) of strain further away of the strain AMLK-135 was low (1.9400) and it was placed further away than the outer-most members in major cluster 5. Therefore, the strain AMLK-135 was identified as a new species of the genus Streptomyces.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.403-407
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• 2007

Several marine. bacterial strains, which were isolated from seawater off the island Dokdo, Korea, were screened to find new bioactive compounds such as antibiotics. Among them, Donghaeana dokdonensis strain DSW-6 was found to produce antibacterial agents, and the agents were then purified and analyzed by LC-MS/MS and 1D- and 2D-NMR spectrometries. The bioactive compounds were successfully identified as cholic acid and glycine-conjugated glycocholic acid, the $7{\alpha}$-dehydroxylated derivatives (deoxycholic acid and glycodeoxycholic acid) of which were also detected in relatively small amounts. Other marine isolates, taxonomically different from DSW-6, were also able to produce the compounds in a quite different production ratio from DSW-6. As far as we are aware of, these bile acids are produced by specific members of the genus Streptomyces and Myroides, and thought to be general secondary metabolites produced by a variety of bacterial taxa that are widely distributed in the sea.

• YAKHAK HOEJI
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• v.49 no.4
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• pp.312-316
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• 2005

To develop a new natural antibiotics from Koran plant resources for dealing with the current situation regarding the rapid increase in antibiotic-resistant pathogen, the in vitro inhibitory activities of essential oils from the young leaves of Glehnia littoralis (Umbelliferae) as well as its main constituents were evaluated against susceptible and resistant species of Streptococcus pneumoniae. The essential oil fraction of G. littoralis and its main components, $\alpha-and\;\beta-pinene$, exhibited significant inhibitory activities against the antibiotic-susceptible and resistant strains of S. pneumoniae, with MICs (minimum inhibiting concentrations) ranging from 4.0mg/ml to 16mg/ml. No remarkable differences were shown between the susceptible and resistant strains. Moreover, the disk diffusion test disclosed that these inhibitory activities were dose­dependent. Furthermore, data from the checkerboard titer test with FICIs (fractional inhibiting concentration indices) from 0.15 to 0.28 indicated synergisms between norfloxacin and $\alpha-or\;{\beta}-pinene$ in activity against S. pneumoniae KCCM49629 and S. pneumoniae CCARM4059.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.26-33
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• 2003

We isolated and identifed culturable Arctic bacteria that have inhabited around Korean Arctic Research Station Dasan located at Ny-Alsund, Svalbard, Norway $(79^{\circ}N,\;12^{\circ}E)$. The pure colonies were inoculated into nutrient liquid media, genomic DNA was extracted, and phylogenetic analysis was performed on the basis of 16S rDNA sequences. Out of total 227 strains, 198 strains were overlapped or unidentified, and 43 bacteria were finally identified: 31 strains belonged to Pseudomonas, 7 strains Arthrobacter, two Flavobacterium sp., an Achromobacter sp., a Pedobacter sp., and a Psychrobacter sp. For isolation of diverse bacteria, we need more effective transport method than 3M petri-films, which were used for convenience of transportation that was restricted by volume. We also need to use other culture media than nutrient media. We expect these Arctic bacteria can be used for screening to develop new antibiotics or industrial enzymes that are active at low temperature.