• BMB Reports
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• v.33 no.1
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• pp.49-53
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• 2000

PMAP-23 is a 23-residue antimicrobial peptide derived from porcine myloid cells. In order to investigate the effects of two Pro residues at positions 12 and 15 of PMAP-23 on antibiotic activity, two analogues in which Ala was substituted for Pro residue at position 12 or 15 were synthesized. $Pro^{12}{\rightarrow}Ala$ (PMAPl) or $Pro^{15}{\rightarrow}Ala$(PMAP2) substitution in PMAP-23 caused a significant reduction on antitumor and phospholipid vesicle-disrupting activities, but did not cause a significant effect on antibacterial activity. PMAP-23 displayed the type I ${\beta}-turn$ structure with a negative ellipticity at near 205 om in SDS micelle, whereas PMAP1 and PMAP2 had a somewhat ${\alpha}-helical$ propensity in TFE solution, as compared to PMAP-23. These results suggest that two Pro residues of positions 12 and 15 in PMAP-23 play important roles in the formation of ${\beta}-turn$ structure on lipid membrane and its ${\beta}-turn$ structure may be essential for antibiotic activity including phospholipid vesicle-disrupting property.

• Journal of Home Health Care Nursing
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• v.26 no.1
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• pp.51-63
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• 2019

Purpose: The objective of this study was to investigate mothers' perception of antibiotic use for their children. Methods: A cross-sectional survey was conducted of a convenient sample of 210 mothers who visited the two pediatric hospitals in D city. Descriptive statistics, t-test, analysis of variance, Kruskal-Wallis test, Mann-Whitney U test, and Pearson correlation coefficients with SPSS WIN 24.0 were used to analyze the data. Results: The perception of mothers on antibiotic use for their children was relatively low (3.28/5) and showed a statistically significant difference based on the mothers' educational background (${\chi}^2=15.30$, p<.001). About 57-77% of participants discontinued or reduced the dosage of the antibiotics if their children's symptoms were relieved, and about 60% of them perceived that antibiotics treat viral infections. Mothers' adherence to specific doses of antibiotics in their children was positively correlated with their knowledge and beliefs (r=.17, p=.014) and their attitude regarding the use of antibiotics (r=.17, p=.014). Only 1.4% of the participants had educational experience regarding the correct use of antibiotics. Conclusion: Based on the results, it can be concluded that an educational program for mothers should be developed and to verify its effects in order to induce proper use of antibiotics among mothers.

• Journal of Pharmacopuncture
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• v.26 no.1
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• pp.53-59
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• 2023

Objectives: The most prominent microorganisms that cause hospital infections and acquire antibiotic resistance are Staphylococcus aureus and Pseudomonas aeruginosa. The present study aimed to compare the phenolic and flavonoid compounds of various Allium ampeloprasum and Allium porrum extracts and evaluate the antibacterial effects of these extracts against these two microorganisms. Methods: The total phenolic and flavonoid contents of the acetone, methanol, aqueous, and hexane leeks extracts from A. ampeloprasum and A. porrum were measured. The antibacterial activity of these extracts against S. aureus and P. aeruginosa was tested using the disk diffusion method for 24, 48, and 72 hours. Further, the minimum inhibitory concentrations and the minimum bactericidal concentrations of these extracts for these two bacteria were evaluated and compared with those of common antibiotics. Results: The aqueous extracts showed the highest phenolic and flavonoid contents and at concentrations of 35 and 40 mg per disk, showed the most antibacterial activity against S. aureus and P. aeruginosa; P. aeruginosa showed more sensitivity to the aqueous extracts than S. aureus. Conclusion: Aqueous A. ampeloprasum and A. porrum extracts may prevent the growth of hospital pathogens, especially P. aeruginosa; our findings will aid the discovery of new antimicrobial substances against antibiotic-resistant bacteria.

• Development and Reproduction
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• v.26 no.4
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• pp.145-153
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• 2022

The gut microbiota is involved in the maintenance of physiological homeostasis and is now recognized as a regulator of many diseases. Although germ-free mouse models are the standard for microbiome studies, mice with antibiotic-induced sterile intestines are often chosen as a fast and inexpensive alternative. Pathophysiological changes in the gut microbiome have been demonstrated, but there are no reports so far on how such alterations affect the bacterial composition of the uterus. Here we examined changes in uterine microbiota as a result of gut microbiome disruption in an antibiotics-based sterile-uterus mouse model. Sterility was induced in 6-week-old female mice by administration of a combination of antibiotics, and amplicons of a bacteria marker gene (16S rRNA) were sequenced to decipher bacterial community structures in the uterus. At the phylum-level, Proteobacteria, Firmicutes, and Actinobacteria were found to be dominant, while Ralstonia, Escherichia, and Prauserella were the major genera. Quantitative comparisons of the microbial contents of an antibiotic-fed and a control group revealed that the treatment resulted in the reduction of bacterial population density. Although there was no significant difference in bacterial community structures between the two animal groups, β-diversity analysis showed a converged profile of uterus microbiotain the germ-free model. These findings suggest that the induction of sterility does not result in changes in the levels of specific taxa but in a reduction of individual variations in the mouse uterus microbiota, accompanied by a decrease in overall bacterial population density.

• Fisheries and Aquatic Sciences
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• v.23 no.8
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• pp.20.1-20.18
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• 2020

Background: Olive flounder, Paralichthys olivaceus, is an economically important aquaculture species in Korea. Olive flounders have been heavily damaged by streptococcal infections every year and are treated with antibiotics. However, antibiotic abuse is causing the emergence of resistant strains, and to overcome this, research has shown that new antibiotics must be applied. Tylosin is a relatively safe antibiotic and has good activity against Gram-positive bacteria and mycoplasma. We studied the therapeutic effects and side effects of tylosin on Streptococcus parauberis-infected olive flounder. Methods: After artificial infection of olive flounder with S. parauberis SPOF18J3, an appropriate dose of tylosin was confirmed by intramuscular injection (I.M.) at 2.5, 5, 10, and 15 mg/kg, and oral administration at 10 and 20 mg/kg. After I.M. and oral administration dosing of tylosin, side effects were confirmed by serological analysis, histopathological analysis, and median lethal dose (LD₅₀) analysis at both an appropriate concentration and a high concentration. Statistical analysis was performed using one-way analysis of variance (ANOVA) and Tukey's test (p < 0.05). Results: The appropriate I.M. and oral administration concentration of tylosin administered to olive flounder infected with S. parauberis SPOF18J3 was found to be 10 mg/kg. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were showed not significantly different between the control group and the experimental groups. The histopathologic results showed mild inflammatory responses in muscle and tubular vacuolization and tubular atrophy appeared, but there were no significant differences between the groups. The LD₅₀ was confirmed to be 461 mg/kg. Conclusion: In this study, an effective treatment method was provided by verifying the treatment effects and side effects of tylosin in olive flounder infected with S. parauberis, which can be applied directly to aquaculture sites. In addition, these results may be used as a reference for evaluation required upon request to obtain approval for tylosin antibiotics as fishery antibiotics in Korea. After approval, it is possible that a fishery disease manager will be able to prescribe and sell the antibiotic tylosin.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1351-1356
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• 2012

The objective of this study was to compare body weight, ADG, and feed:gain ratio of antibiotic-free pigs from Yorkshire dams and sired by Yorkshire (YY), Berkshire (BY), Large Black (LBY) or Tamworth (TY) boars. All the crossbred pigs in each of three trials were raised as one group from weaning to finishing in the same deep-bedded hoop, providing a comfortable environment for the animals which allowed rooting and other natural behaviors. Birth, weaning and litter weights were measured and recorded. From approximately 50 kg to market weight (125 kg), feed intake and body weights were recorded manually (body weight) or using a FIRE (Feed Intake Recording Equipment, Osborne Industries Inc. Osborne, Kansas) system with eight individual feeding stations. Feed intake data for 106 finishing pigs between 140 and 210 d of age and the resulting weights and feed conversion ratios were analyzed by breed type. Least square means for body weights (birth, weaning and to 240 d) were estimated with Proc Mixed in SAS 9.2 for fixed effects such as crossbreed and days of age within the sire breed. The differences within fixed effects were compared using least significant differences with DIFF option. Individual birth weights and weaning weights were influenced by sire breed (p<0.05). For birth weight, BY pigs were the lightest, TY and YY pigs were the heaviest but similar to each other and LBY pigs were intermediate. For weaning weights, BY and LBY pigs were heavier than TY and YY pigs. However, litter birth and weaning weights were not influenced by sire breed, and average daily gain was also not significantly different among breed types. Tamworth sired pigs had lower overall body weight gain, and feed conversion was lower in TY and YY groups than BY and LBY groups (p<0.05), however, number of observations was somewhat limited for feed conversion and for Tamworth pigs. Overall, no convincing differences among breed types were noted for this study, but growth performance in the outdoor environment was satisfactory.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.406-411
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• 2006

The objective of this study was to investigate the effects of feeding probiotic (Enterococcus faecium SF68, EF) on growth performance, nutrient digestibility, blood characteristics and faecal noxious gas content in finishing pigs. A total of eighty [($Landrace{\times}Yorkshire$)${\times}Duroc$] pigs with an initial BW of $50.47{\pm}2.13kg$ were used in this 8-week experiment. Pigs were allotted to four treatments (4 replicates per treatment and 5 pigs per pen) according to a randomized complete block design. Dietary treatments were: 1) CON (control; basal diet), 2) CTC (control diet+0.1% antibiotic, chlortetracycline), 3) EF1 (control diet+0.1% probiotic, EF) and 4) EF2 (control diet+0.2% probiotic, EF). During weeks 0-4, ADG was not affected by the addition of antibiotic or EF (p>0.05). In weeks 4-8, ADG tended to increase in CTC and EF treatments compared to CON treatment (p<0.10). ADFI and gain/feed were not affected in each 4-week period and the entire experimental period (p>0.05). Digestibilities of DM and N were higher in EF supplemented treatments than in CON and CTC treatments (p<0.05). Blood characteristics of WBC, RBC and lymphocyte were not affected in pigs given diets containing EF (p>0.05). Supplementation of EF in the diet decreased faecal ammonia nitrogen ($NH_3$-N) and hydrogen sulphide ($H_2S$) concentrations (p<0.05). Faecal acetic acid concentration tended to decrease (p<0.10) while propionic acid and butyric acid concentrations were significantly lower on diets with EF supplementation than on the diet containing antibiotic (p<0.05). In conclusion, dietary supplementation of EF can increase nutrient digestibility and decrease faecal $NH_3$-N, $H_2S$ and volatile fatty acid (VFA) concentrations in finishing pigs.

• Restorative Dentistry and Endodontics
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• v.46 no.4
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• pp.52.1-52.11
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• 2021

Objectives: This study evaluated the effects of low and moderate concentrations of triple antibiotic paste (TAP) and double antibiotic paste (DAP) loaded into a hydrogel system on crown discoloration and explored whether application of an adhesive bonding agent prevented crown discoloration. Materials and Methods: Intact human molars (n = 160) were horizontally sectioned 1 mm apical to the cementoenamel junction. The crowns were randomized into 8 experimental groups (calcium hydroxide, Ca[OH]₂; 1, 10, and 1,000 mg/mL TAP and DAP; and no medicament. The pulp chambers in half of the samples were coated with an adhesive bonding agent before receiving the intracanal medicament. Color changes (ΔE) were detected by spectrophotometry after 1 day, 1 week, and 4 weeks, and after 5,000 thermal cycles, with ΔE = 3.7 as a perceptible threshold. The 1-sample t-test was used to determine the significance of color changes relative to 3.7. Analysis of variance was used to evaluate the effects of treatment, adhesive, and time on color change, and the level of significance was p < 0.05. Results: Ca(OH)₂ and 1 and 10 mg/mL DAP did not cause clinically perceivable tooth discoloration. Adhesive agent use significantly decreased tooth discoloration in the 1,000 mg/mL TAP group up to 4 weeks. However, adhesive use did not significantly improve coronal discoloration after thermocycling when 1,000 mg/mL TAP was used. Conclusions: Ca(OH)₂ and 1 and 10 mg/mL DAP showed no clinical discoloration. Using an adhesive significantly improved coronal discoloration up to 4 weeks with 1,000 mg/mL TAP.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.3
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• pp.293-299
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• 2023

Acne vulgaris is often associated with acne-related bacteria such as Cutibacterium acnes. In this study, we investigated the antibacterial effects of the methanol extract of the algae Ecklonia cava and its solvent-soluble extract against C. acnes. Among five solvent fractions, the ethyl acetate (EtOAc) fraction exhibited the strongest antibacterial activity against C. acnes. Furthermore, the EtOAc-soluble extract exhibited the highest total phenolic contents among the five solvent fractions tested. The EtOAc subfraction 07 (Fr. 07) extract showed the highest antibacterial effect against C. acnes and isolated C. acnes along with minimum inhibitory concentration (MIC) ranging from 32 to 64 ㎍/mL. Additionally, MICs of antibiotics against antibiotic-resistant C. acnes strains were substantially reduced when antibiotics were combined with Fr. 07, suggesting that Fr. 07 restore the antibacterial activity of the antibiotics. The fractional inhibitory concentration indices clearly revealed an additive synergistic effect of Fr. 07 with antibiotics. The results of the present study suggest a potential role for E. cava in the control of infections related to acne vulgaris.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.6
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• pp.396-401
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• 2013

Chronic osteomyelitis is an infection and inflammation of the bone or bone marrow, causing ischemia in bone marrow due to lack of blood, nutrients, and oxygen supply to the bone marrow, eventually leading to necrosis of bone marrow. A current method for treatment of chronic osteomyelitis is administration of systemic antibiotics followed by removal of the infected bone and tissues. Because infected tissue of chronic osteomyelitis is surrounded by avascular necrotic bone, supply of blood and antibiotics to the infected area is diminished. For effective treatment, high plasma concentrations of antibiotics should be provided for a prolonged period. However, long term high serum level of antibiotics may result in undesirable adverse effects. For delivery of a sufficient concentration of antibiotic to the infected area while avoiding the adverse effect, implantation of a local antibiotic delivery system is suggested. One of the implantation systems that has been utilized is antibiotic impregnated polymethyl methacrylate.