• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.233-234
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• 2001

Marine microorganisms have a diverse range of enzymatic activity and are capable of catalyzing various biochemical reactions with diverse enzymes. There have been several studies reporting that various sulfatases isolated from such bacteria as Klebsiella pneumoniae (Miech et al., 1998), Salmonella typhimurium (Henderson and Milazzo, 1979; Murooka and Harada, 1981), Serratia marcescens (Murooka et al., 1980), Pseudomonas aeruginosa(Delisle and Milazzo, 1970), and Comamonas terigena(Fitzgerald and Cline, 1977). (omitted)

• YAKHAK HOEJI
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• v.35 no.6
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• pp.515-521
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• 1991

A number of 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-substitutedcarbamyl-1-piperazinyl) quinoline [or 1,8-naphthyridine]-3-carboxylic acid and their pivaloyloxymethyl esters were prepared. The compounds synthesized were evaluated for antibacterial activity in vitro against Escherichia coli, Bacillus subtilis, Proteus vulgaris, Klebsiella pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa. Among those 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-methylcarbamyl-1-piperazinyl) quinoline-3-carboxylic acid [1] and 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-methylcarbamyl-1-piperazinyl)1,8-naphthyridine-3-carboxylic acid [6] showed the most potent in vitro antibacterial activity.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.353-359
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• 1991

Treatment of 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7-(l-piperazinyl)-I, 8- naphthyridine-3-ca rboxylic acid (Enoxacin) with alkyl(or aryl) isothiocyanates which obtained from alkyl(or aryl) amines afforded six 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7-(1-alkylthiocarbamylpiperazinyl)-1, 8- naphthyridine-3-carboxylic acids and five 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7-(l-arylthiocarbamyl piperazinyl)-1, 8-naphthyridine-3-carboxylic acids. The compounds synthesized were evaluated for their antimicrobial activities, in vitro, against Escherichia coli 6-PE-4, Bacillus subtilis 74-51, Proteus vulgaris 78645, Klebsiella pneumoniae JYA-78314, Staphylococcus aureus 79110 and Pseudomonas aeruginosa 8765-1 P$_{2}$.

• Journal of Microbiology
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• v.39 no.2
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• pp.146-148
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• 2001

Lactobacillus crispatus ATCC 33820 and L. gasseri ATCC 33323 were grown in MRS broth (pH 6.5) at 37$^{\circ}C$ for 24 h and the antibacterial activities of cell free culture supernatants were determined by the agar well diffusion method. The culture supernatants were inhibitory to Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Pediococcus acidilacticii, and Lactobacillus helveticus. The supernatants did not show any lysozyme activity. Addition of catalase did not affect the antibacterial activities of the supernatants. The antibacterial substances were heat stable (100$^{\circ}C$ for 60 min) and sensitive to proteases.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.50-56
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• 1997

Applied for Drug Delivery System, polymer drug was prepared with chitosan and phthalylsulfathiazole. In spite of various application of chitin derivatives, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. In this study, Chitosan were prepared from chitin which were deacetylated under various condition. The synthetic procedures of polymer drug were performed by acid chloride methods. The antibiotic activities of polymer drug exhibited growth-inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, E. coli, Salmonella typhimurium, Klebsiella pneumoniae at the concentration of 471-514 $\mu$g/ml in general. Comparatively, Polymer drug exhibited broad antibacterial activity on MICs 897-1280 $\mu$g/ml against Gram-positive and Gram-negative bacteria including Staphylococcus aureus, Staphylococcus epidermidis and E. coli.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.500-506
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• 1996

To study antimicrobial activities of Impatiens balsamina, its leaf and stem was extracted by methanol and water. The extracts were tested their microbial inhibition activities against several microorganisms, staphylococcus aureus KCTC 1928, Escherichia coli KCTC 1116, Klebsiella pneumoniae KCTC 2690, Trichophyton mentagrophytes KCTC 6316. The methanol extract and water extract of the leaf and stem didn't show the inhibition effect on E. coli but showed the inhibition effect against the ohter 3 species of the microorganisms tested. The extract of leaf showed higher inhibition than the extract of stem. And the methanol extract showed higher inhibition than the water extract.

• Journal of the Korean Ceramic Society
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• v.50 no.4
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• pp.245-250
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• 2013

A hydroxyapatite air filter was made with hydroxyapatite powder, water and chitosan solution. The structures of the sintered HAp samples were determined by MP-XRD. Hydroxyapatite has antibacteria properties against Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. The bacteria removal rate was 99.9%. In the case of Pseudomonas aeruginosa, Colon bacterium and Listeria monocytogenes, the hydroxyapatite air filters had a clear zone which confirmed antibacteria properties. Using the microscopy, we observed that the HAp powder absorbed E. coli bacteria.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.1-10
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• 2019

Gram-negative pathogens, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, pose a serious threat to public health worldwide, due to high rates of antibiotic resistance and the lack of development of novel antimicrobial agents targeting Gram-negative bacteria. The outer membrane (OM) of Gram-negative bacteria is a unique architecture that acts as a potent permeability barrier against toxic molecules, such as antibiotics. The OM is composed of phospholipids, lipopolysaccharide (LPS), outer membrane ${\beta}-barrel$ proteins (OMP), and lipoproteins. These components are synthesized in the cytoplasm or in the inner membrane, and are then selectively transported to the OM by the specific transport machines, including the Lol, BAM, and Lpt pathways. In this review, we summarize recent studies on the assembly systems of OM components and analyze studies for the development of inhibitors that target these systems. These analyses show that OM assembly machines have the potential to be a novel attractive drug target of Gram-negative bacteria.

• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.257-266
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• 2005

Background : The study of pneumonia among young men living in a group is rare. prospective study was conducted to determine the etiology, and compare the effects of macrolide and second-generation cephalosporin on the treatment of pneumonia among combat policemen. Patients and Methods : From January 2003 to April 2004, Fifty-two patients with pneumonia were treated with either azithromycin(n=25) or cefuroxime(n=27). In order to determine the cause of the pneumonia, culture studies and serologic tests for antibodies to Mycoplasma pneumoniae and Chlamydia pneumoniae were carried out. During the two weeks of medication, the Chest X-rays, blood tests and culture studies(if necessary) were followed weekly. A serologic study was followed at the end of the second week. Results : The main pathogens for pneumonia among combat policemen were Mycoplasma pneumoniae(50.0%), Chlamydia pneumoniae(10.8%), and Streptococcus pneumoniae(3.8%). The treatment was successful in most cases(51/52 cases, 98.1%). The effects of azithromycin and cefuroxime were similar (96.0% vs 100%, p>0.05). In one patient who had taken azithromycin, the clinical and radiological findings did not improved until intravenous second generation ce phalosporin had been infused. Conclusion : Atypical pathogens were the main causes of the pneumonia in the combat policemen, and the effects of macrolide and second generation cephalosporin for pneumonia were similar. However, further studies will be needed to determine if single therapy with macrolide is possible.

• Pediatric Infection and Vaccine
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• v.22 no.3
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• pp.178-185
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• 2015

Purpose: We investigated trends in antibiotic pressure and the antibiotic susceptibility of gram negative bacteria isolated from Korean children over 10 consecutive years. Methods: From January 2004 to December 2013, the antibiotic susceptibility of Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii blood isolates obtained from children <18 years of age was determined according to the 2009 Clinical and Laboratory Standards Institute guidelines. Antibiotic consumption data were also analyzed. Results: The prevalence of K. pneumoniae, E. coli, P. aeruginosa, and A. baumannii bacteremia was 4.6, 3.5, 3.4, and 2.2 cases/1,000 blood cultures/year, respectively. In K. pneumoniae, resistance to the third and fourth cephalosporin did not increase significantly. However, carbapenem-resistant K. pneumoniae first appeared in 2010, and the resistance rate increased to 9% between 2012 and 2013. Resistance to 3rd and 4th cephalosporin increased from 10% to 50% in E. coli, and resistance to carbapenem rose abruptly from 11% to 71% in A. baumannii (P for trend <0.01). However, such an increase of resistance was not observed in P. aeruginosa. There is a positive correlation between the resistance rate of cefepime in E. coli and the consumption of cefepime (r=0.900, P=0.037). Conclusion: The significant burden of antibiotic consumption and the high prevalence of antibiotic resistance to gram negative pathogen isolated from bacteremic children were observed. Empirical antibiotics should be wisely selected, and continued efforts to decrease the overall antibiotic pressure are mandatory, especially in highly resistant situations.