• The Plant Pathology Journal
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• v.40 no.5
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• pp.525-536
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• 2024

Agrochemicals containing antibiotics are authorized to manage fire blight that has been occurring in Korea since 2015. The minimum inhibitory concentration (MIC) of each antibiotic against Erwinia amylovora, the causal pathogen of fire blight, has increased over the years due to the pathogen's frequent exposure to antibiotics, indicating the necessity to prepare for the emergence of antibiotic resistance. In this study, E. amylovora was exposed to stepwise increasing concentrations of eight different agrochemicals, each containing single or mixed antibiotics, and gene mutation and changes in MIC were assessed. Streptomycin and oxolinic acid induced an amino acid substitution in RpsL and GyrA, respectively, resulting in a rapid increase in MIC. Oxytetracycline initially induced amino acid substitutions or frameshifts in AcrR, followed by substitutions of 30S small ribosomal protein subunit S10 or AcrB, further increasing MIC. E. amylovora acquired resistance in the order of oxolinic acid, streptomycin, and oxytetracycline at varying exposure frequencies. Resistance acquisition was slower against agrochemicals containing mixed antibiotics than those with single antibiotics. However, gene mutations conferring antibiotic resistance emerged sequentially to both antibiotics in the mixed formulations. Results suggested that frequent application of mixed antibiotics could lead to the emergence of multidrug-resistant E. amylovora isolates. This study provided essential insights into preventing the emergence of antibiotic-resistant E. amylovora and understanding the underlying mechanisms of resistance acquisition.

• Journal of Environmental Health Sciences
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• v.38 no.2
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• pp.142-150
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• 2012

Objectives: To estimate the multi-antibiotic resistant bacterial contaminant load discharged from livestock farms, we randomly selected livestock farms specializing in cattle, swine, and fowl and collected bacterial strains from domesticated animal feces and compost samples. Problems with resistance to antibiotics are becoming worldwide issues, and as the consumption of antibiotics appears to be excessive in Korea as well, the emergence of antibiotic resistant bacteria shows the possibility to cause potentially serious social problems. Methods: To monitor multi-antibiotic resistant bacterial constituents, aerobic bacteria and Escherichia coli were isolated from domesticated animal feces and compost. Antibiotic resistance testing was performed by the disc diffusion method using 13 different antibiotics. Results: Examining the degree of sensitivity to antibiotics of the aerobic bacteria originating from domesticated animal feces, fowl feces showed the highest distribution rate (35.5%), followed by swine feces compost (23.1%), swine feces (18.2%), cattle feces (14.9%), and cattle feces compost (8.2%). Antibiotic resistance tests of aerobic bacteria and E. coli originating from domestic animals feces resulted in 83.6% and 73.5% of each strain showing resistance to more than one antibiotic, respectively. Conclusions: These results suggest that increasing multi-antibiotic resistant bacteria in the environment has a close relation to the reckless use of antibiotics in livestock.

• Korean Journal of Clinical Pharmacy
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• v.12 no.2
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• pp.65-70
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• 2002

Prophylactic antibiotics in acute nonperforated appendicitis have been used for preventing infection after appendectomy. However, duration of antibiotic administration for surgical prophylaxis in Korea has been noted to be longer than those recommended in other countries. The objective of this study was to identify appropriate duration of prophylactic antibiotics in acute nonperforated appendicitis by comparing two different antibiotic regimens for their wound infection rates. Eighty-four acute nonperforated appendicitis patients were enrolled in this prospective, randomized, open trial and were assigned to one of two antibiotic regimens: cefoxitin 1 g every 8 hours given intravenously for 24hours or cefoxitin 1 g every 8 hours given intravenously plus sisomicin 75 mg every 12 hours given jntramuscularly for 72 hours. First doses were given just prior to the induction of anesthesia. Postoperative wound infections were detected in $4.8\%$ of the 72-hour-treated group (n=42), whereas none occurred in the 24-hour-treated group (n=42). However, the difference in the rates of wound infections between two groups was not statistically significant. The most frequently isolated microorganism from appendiceal tissues was E coli. In conclusion, administration of cefoxitin alone for 24 hours is sufficient as surgical prophylaxis in nonperforated appendicitis.

• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.89-93
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• 2019

Background: Prophylactic antibiotic administration after surgery for a nasal bone fracture is performed due to concerns about infection-related complications, such as, toxic shock syndrome. To evaluate the validity and efficacy of antibiotic use, we compared the results obtained and the bacterial profiles of nasal packing materials in patients that underwent closed reduction for a nasal bone fracture with or without prophylactic antibiotic administration. Methods: Thirty consecutive patients with a nasal bone fracture, but without an open wound, that underwent closed reduction during March to August 2017 were included in the present study. Fifteen of these 30 patients were randomly assigned to a control group, members of were administered postoperative intravenous antibiotics once at the day of surgery and then oral antibiotics for 4 days. The other 15 patients were assigned to an experimental group and not administered any antibiotic postoperatively. Antibiotic ointment was not applied to nasal packing in either group. Nasal packing was removed on postoperative day 4 in all cases. Removed nasal gauze packings were culture tested and strains identified in the two groups were compared. Results: Bacterial strain types cultured from packings were similar in the experimental and control groups and no patient showed signs of clinically significant infection. Conclusion: The findings of this study suggest postoperative prophylactic antibiotic use is not clinically required after closed reduction of a nasal bone fracture. Furthermore, the non-use of postoperative antibiotics is biologically beneficial, as it reduces the occurrence of resistant strains and medical costs, and is more convenient for patients.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.25 no.4
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• pp.240-249
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• 2018

Purpose: The study was done to explore whether the duration of perioperative prophylactic antibiotics therapy influenced uncertainty of recovery in patients with elective laparoscopic uterine myomectomy. Methods: A prospective study was conducted using self-report questionnaires and electrical medical records for patients with uterine myomectomy. According to the length of the perioperative prophylactic antibiotics therapy, the patients were divided into three groups: single-dose antibiotic treatment group, short-term antibiotic treatment group, and long-term antibiotic treatment group. Data were collected from December 20, 2016 to July 31, 2017 from 161 patients who underwent laparoscopic myomectomy at a metropolitan city general hospital. Results: Level of uncertainty of recovery was $2.98{\pm}0.22$. The uncertainty was highest in the long-term antibiotic treatment group, followed by the short-term antibiotic treatment group and the single-dose antibiotic treatment group (F=89.40, p<.001). In the regression analysis, factors influencing uncertainty of recovery among uterine myomectomy patients were duration of perioperative prophylactic antibiotic therapy (${\beta}=.70$, p<.001) and duration of NPO (${\beta}=-.11$, p=.047) which explained 51.5% of the variance (F=83.75, p<.001). Conclusion: Based on these results, information including the administration of antibiotics before surgery should be provided to the patients to help reduce the uncertainty of postoperative recovery.

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.180.3-181
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• 2001

• Research in Plant Disease
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• v.28 no.3
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• pp.166-171
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• 2022

Commercial products with antibiotics like streptomycin as active ingredients have been used to control soft rot disease caused by Pectobacterium species for a long time. In this study, antibiotic resistance of twenty-seven Korean strains of Pectobacterium species including P. carotovorum, P. odoriferum, P. brasiliense, and P. parmenteri, which were previously shown to be susceptible to the bacteriophage phiPccP-1 was surveyed using a disk diffusion assay. While all strains were highly susceptible to ampicillin, kanamycin, chloramphenicol, tetracycline, and rifampicin, some strains showed weak susceptibility to 300 ㎍/ml of streptomycin. Furthermore, some of them are partially or completely resistant to commercial pesticides-Buramycinand streptomycin at the concentration of 250 ㎍/ml that is recommended by the manufacturer for streptomycin-based pesticides. These results indicate the presence of streptomycin-resistant Pectobacterium strains in South Korea, and the development of antibiotic alternatives to control soft rot is needed.

• Journal of Korean Neurosurgical Society
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• v.56 no.1
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• pp.34-41
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• 2014

Objective : The purpose of this study was to describe the clinical characteristics, treatment outcomes, and prognostic factors in patients with brain abscesses treated in a single institute during a recent 10-year period. Methods : Fifty-one patients with brain abscesses who underwent navigation-assisted abscess aspiration with antibiotic treatment were included in this study. Variable parameters were collected from the patients' medical records and radiological data. A comparison was made between patients with favorable [Glasgow Outcome Scale (GOS) ${\geq}4$] and unfavorable (GOS <4) outcomes at discharge. Additionally, we investigated the factors influencing the duration of antibiotic administration. Results : The study included 41 male and 10 female patients with a mean age of 53 years. At admission, 42 patients (82%) showed either clear or mildly disturbed consciousness (GCS ${\geq}13$) and 24 patients (47%) had predisposing factors. The offending microorganisms were identified in 25 patients (49%), and Streptococcus species were the most commonly isolated bacteria (27%). The mean duration of antibiotic administration was 42 days. At discharge, 41 patients had a favorable outcome and 10 had an unfavorable outcome including 8 deaths. The decreased level of consciousness (GCS <13) on admission was likely associated with an unfavorable outcome (p=0.052), and initial hyperglycemia (${\geq}140mg/dL$) was an independent risk factor for prolonged antibiotic therapy (p=0.032). Conclusion : We found that the level of consciousness at admission was associated with treatment outcomes in patients with brain abscesses. Furthermore, initial hyperglycemia was closely related to the long-term use of antibiotic agents.

• Korean Journal of Pharmacognosy
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• v.40 no.3
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• pp.173-177
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• 2009

The in vitro antibacterial activities of honeybee(Apis mellifera. L) venom collected by a bee venom collector were investigated against several bacteria including antibiotic-susceptible and resistant Propionibacterium acnes. Honeybee venom was prepared with different concentrations and they showed strong antibacterial activites. Honeybee venom inhibited the growth of the tested antibiotic-resistant P. acnes at the concentration of 1 mg/ml. The inhibitory activities of the honeybee venom showed time-dependent manner. Honeybee venom did not influence the viability of human dermal fibroblast at the high concentration of less than 10 mg/ml. From these results, we expect that honeybee venom has strong antibacterial activities and has advantage for treating cure.

• Journal of Environmental Health Sciences
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• v.37 no.4
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• pp.289-297
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• 2011

Objectives: To estimate the microbial contaminant load discharged from livestock farms, we randomly selected livestock farmers of cattle, swine, and fowl and collected bacterial strains from domestic animals' feces and compost samples. Recently, as multi-antibiotic-resistant bacteria and super bacteria showing resistance to a variety of antibiotics have been reported one after another, the ecological and health hazard of antibiotic-resistant bacteria is emerging as an important issue. Methods: Monitored indicator microorganism constituents were totak coliform (TC), fecal coliform (FC), and aerobic bacteria. The multi-antibiotic-resistant bacteria were identified from investigated indicator microorganisms by 16S rRNA sequencing. Results: By microbiological analysis, the largest population of aerobic bacteria ($1.5{\times}10^5$ CFU/g) was found in cattle fecal compost, and total coliforms ($1.1{\times}10^7$ CFU/g) and fecal coliforms ($1.0{\times}10^5$ CFU/g) were found primarily in swine fecal compost, while the lowest population was found in fowl fecal compost. Among the 67 strains separated from aerobic bacteria, five strains expressing high antibiotic resistance were selected in each sample. We found the multi-antibiotic resistant strains to be Shigella boydii, Staphylococcus lentus, Acinetobacter sp. and Brevibacterium luteolum. Conclusions: These results suggest that increasing numbers of multi-antibiotic-resistant bacteria in the environment have a close relation to the reckless use of antibiotics with livestock.