• The Journal of Pediatrics of Korean Medicine
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• v.32 no.2
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• pp.64-71
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• 2018

Objectives The purpose of this study is to examine the correlation of antibiotics administration duration and antimicrobial resistance by reviewing domestic and foreign literatures. Methods We searched literatures dated up to 23 February, 2018 in PubMed and Cochrane Library using terms of "Anti-Bacterial Agents", "Carrier State", "Nasopharynx", "Drug Administration Schedule", and also searched via RISS (Research Information Service System), KISS (Koreanstudies Information Service System), DBpia (DataBase Periodical Information Academic) using terms of antibiotics, resistance, and dose. Results In comparison with shortened and standard antibiotic course, longer treatment duration is associated with greater antimicrobial resistance or non-significant difference, but we cannot find literature that shortened antibiotic course increases antimicrobial resistance on human nasopharyngeal flora. Conclusions Currently, there is no evidence that completing the standard antibiotic course reduces antimicrobial resistance. It can be a strategy for reducing antibiotic use to apply Korean medicine treatment, as well as short-course antibiotic therapy or delayed antibiotic prescription. Additional well-designed trials should be conducted in domestic and foreign settings about the appropriate duration of antibiotic therapy.

• Pediatric Infection and Vaccine
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• v.16 no.1
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• pp.6-12
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• 2009

There are relatively few novel antimicrobial agents despite the dramatic increase in antimicrobial resistance and multiple drug resistance of clinical isolates worldwide. Vancomycin is still the most widely used antibiotic for treating resistant Gram-positive coccal infections in children, especially for methicillin-resistant Staphylococcus aureus. For children with Gram-positive coccal infections where vancomycin is not effective or older therapeutic agents cannot be tolerated, linezolid, quinupristin-dalfopristin or daptomycin may be useful in the appropriate clinical setting. For Gram-negative bacterial infections, new carbapenems await clinical application. Tebipenem pivoxil is a novel oral carbapenem undergoing clinical trials for acute otitis media in pediatric patients. Antiviral drug development is now progressing at the pace of antibiotic development 30 years ago. Newer antiviral agents used for the treatment of herpes viruses and hepatitis C virus infections in children are included in this review.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.541-544
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• 2004

The purpose of this study is to examine the antibiotic and physical properties of antibiotic concrete added inorganic liquor-type antibiotic agent(as named for Antibio-C) as the basic data for the development of antibiotic concrete. The main experimental variables were the types of antibiotic agents and it is tested for the properties of antibiotic, flow, compressive strength, crack-resistance and durability of concrete. As results, concrete containing antibiotic agent presented the strong antibiotic activities compared with non-added concrete. Also antibiotic concrete showed the higher or equality properties than non-added concrete with respect to compressive strength, crack resistance and durability such as neutralization depth.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.202-215
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• 1996

The purpose of this study was to an in estigate the antibiotic susceptibiliity of Actinoobacillus actinomycetemcomitans isolated from the subgingival plaque to adult periodontitis. Seven bacterial strains were tested for their susceptibility to 10 antimicrobial agents under disk diffusion method and broth dilution methold, Seven patients with deep pocket(6mm) were selected for this study. They had not taken antibiotics for 6 months and no history of dental treatment for 6 months and no history of dental treatment for 6 months before this study. The results were as follows : 1. For the antibiotic disk diffusion method, seven A. actinimycetemcomitans were tested with 10 antimicrobial agents which comprised penicillin, gentamycin, clindamycin, lincomycin, ampicillin, erythromycin, tetracycline, amikacin, chloramphenicol, and vancomycin. The sensitive antibiotics were tetracycline, vancomycin, and chloramphenicol and the resistant antibiotics were clindamycin, and lincomycin. The other antimicrobial agents were less active. 2. From the study of determination on the minimal inhibitory concentration(MIC) by broth dilution method, the MIC of tetracycline to seven strains of the A. actinomycetemcomitans was $0.5-1.0{\mu}g/ml$, that of clindamycin was $32{\mu}g/ml$. These data suggest that tetracycline may be valuable drugs in the elimination of A. actinimycetemcomitans from the patients with adult periodontitis

• Natural Product Sciences
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• v.28 no.3
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• pp.93-104
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• 2022

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious threat to the global healthcare system. Ineffective and resistance to antibiotic treatments have increased morbidity and mortality rates worldwide. New and effective antibiotics are needed to combat against bacterial resistance. Endophytic fungi are crucial reservoirs of novel bioactive metabolites. In particular, the secondary metabolites show promising therapeutic potential, notably, antibacterial. This review discussed the emerging potential of endophytic fungi as anti-MRSA agents. The ecological sources of endophytic fungi were discussed with the synthesis of bioactive metabolites. The mode of antibacterial actions was elucidated to give a better understanding of the mechanisms involved. This review may serve as an important reference for future discovery and developments of anti-MRSA agents from endophytic fungi.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1039-1046
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• 2005

The salt resistance of antibacterial activity and synergistic effect with clinically used antibiotic agents are critical factors in developing effective peptide antibiotic drugs. For this reason, we investigated the resistance of antibacterial activity to antagonism induced by NaCl and $MgCl_2$ and the synergistic effect of P20 with cefotaxime. P20 is a 20-residue synthetic peptide derived from a cecropin A (CA)-melittin(ME) hybrid peptide. In this study, P20 was found to have potent antibacterial activity against clinically isolated methicillin-resistant Staphylococcus aureus (MRSA) strains without hemolytic activity against human erythrocytes. The combination study revealed that P20 in combination with cefotaxime showed synergistic antibacterial activity in an energy-dependent manner. We also confirmed the synergism between P20 and cefotaxime by fluorescence-activated flow cytometric analysis by staining bacterial cells with propidium iodide (PI) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol (BOX). This study suggests that P20 may be useful as a therapeutic antibiotic peptide with synergistic effect in combination with conventional antibiotic agents.

• BMB Reports
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• v.38 no.5
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• pp.507-516
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• 2005

Antimicrobial peptides (AMPs) have been isolated and characterized from tissues and organisms representing virtually every kingdom and phylum. Their amino acid composition, amphipathicity, cationic charge, and size allow them to attach to and insert into membrane bilayers to form pores by 'barrel-stave', 'carpet' or 'toroidal-pore' mechanisms. Although these models are helpful for defining mechanisms of AMP activity, their relevance to resolving how peptides damage and kill microorganisms still needs to be clarified. Moreover, many AMPs employ sophisticated and dynamic mechanisms of action to carry out their likely roles in antimicrobial host defense. Recently, it has been speculated that transmembrane pore formation is not the only mechanism of microbial killing by AMPs. In fact, several observations suggest that translocated AMPs can alter cytoplasmic membrane septum formation, reduce cell-wall, nucleic acid, and protein synthesis, and inhibit enzymatic activity. In this review, we present the structures of several AMPs as well as models of how AMPs induce pore formation. AMPs have received special attention as a possible alternative way to combat antibiotic-resistant bacterial strains. It may be possible to design synthetic AMPs with enhanced activity for microbial cells, especially those with antibiotic resistance, as well as synergistic effects with conventional antibiotic agents that lack cytotoxic or hemolytic activity.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.676-681
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• 2010

Antibiotic resistant bacteria were isolated from livestock wastes and the resistance patterns were investigated using various antibiotic agents. Also, a gamma ray was tested regarding the aspects of the effect on resistance pattern and the efficiency of disinfection. Among the isolates, Esherichia coli and Brevibacterium sp. showed the most serious resistance patterns. Esherichia coli had resistance against 9 agents whereas Brevibacterium sp. against 7 agents. It can be suggested from these results that the abuse of antibiotic agents will cause a serious mutation problem even to Esherichia coli which is ubiquitous in the ecosystem. Esherichia coli could be easily controlled but Brevibacterium sp. had a moderate resistance to the gamma ray under low doses. In the case of Brevibacterium sp, more than 2.0 kGy of a radiation dose will be required in order to achieve an enhanced efficiency of disinfection.

• The Journal of the Korean Society for Microbiology
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• v.34 no.6
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• pp.543-554
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• 1999

The purpose of this study was to evaluate the existence of amoxicillin, clarithromycin, and metronidazole resistance Helicobacter pylori and to determine the in-vitro MIC of two and three kinds of antibiotic concominant administration in the isolates. The antimicrobial agents tested against 169 H. pylori included metronidazole, amoxicillin, ciprofloxacin, clarithromycin, omeprazole, josamycin, erythromycin, and tetracycline. MIC of each antimicrobial agents was determined by broth microdilution method. The 169 strains of H. pylori were isolated from biopsy specimens of patients with gastric cancer. $MIC_{50}$ of clarithromycin, amoxicillin, metronidazole, omeprazole, erythromycin, josamycin, tetracycline, and ciprofloxacin was 2.0, 1.0, 4.0, 8.0, 0.5, 0.5, and $0.5\;{\mu}g/ml$, respectively. $MIC_{90}$ of clarithromycin, amoxicillin, metronidazole, omeprazole, erythromycin, josamycin, tetracycline, and ciprofloxacin was 64.0, 64.0, 32.0, 16.0, 8.0, 2.0, and $1.0\;{\mu}g/ml$, respectively. H. pylori isolates were detected in the following resistaince rates: 34.3% to clarithromycin, 31.9% to metronidazole, 20.7% to amoxicillin, 12.4% to erythromycin, and 10.1% to josamycin. The prevalence of the antibiotic resistant strains of H. pylori were detected 18.1% for two kind of antibiotics and 9.6% for three kind of antibiotics, and 3.9% for four kind of antibiotics. The $MIC_{90}$ of clarithromycin-, metronidazole-, and amoxicillin-resistant H. pylori was decreased under the $1\;{\mu}g/ml$ by the two or three kind of antibiotic concomitant administration in-vitro. These results suggest that two or three antibiotics concomitant administration could be more effective for the treatment of clarithromycin-, amoxicillin-, metronidazole-, and josamycin-resistant H. pylori strains.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.191-196
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• 1999

A multifunctional antagonistic bacterium, producing both antifungal antibiotic and chitinase that could be used as biocontrol agents against fungal plant pathogens was isolated from the plant-disease suppressive soil. The isolate was identified as Promicromonospora sp. KH-28 from various morphological, biochemical and physiological tests. The antifungal antibiotic produced by Promicromonospora sp. KH-28 was soluble in n-butanol, methanol, toluene, n-hexane, ethanol but insoluble in H2O, acetone, chloroform, ethylacetate and ethylether. It inhibited the growth of fungal plant pathogens of Fusarium solani, F. oxysporum, Alternaria mali and Phytophthora capsici. The antagonistic Promicromonospora sp. KH-28 produced optimally the antifungal antibiotic when it was cultivated at pH 7, 3$0^{\circ}C$ for 5 days.