엔로플록사신 액제의 닭 호흡기 및 소화기 감염증에 대한 예방 및 치료효과

윤효인,박병권,조준형,정상희,박경환,장범수,김종춘,황윤환,임종환,이내경,박승춘 충남대학교 수의과대학 동물의과학연구소 2000 動物醫科學硏究誌 Vol.8 No.-

We evaluated the efficacy of the liquid form of enrofloxacin against poultry respiratory and digestive infections, the major problems in the poultry industry, from diverse diagnosis viewpoints. Results obtained through this study were as follows: 1. The liquid form of enrofloxacin showed good acceptability to poultry owing to no abhorrence to the drug by chickens, which indicated its suitability for mixing in drinking water. 2. The application of the enrofloxacin formulation improved the productivity of the chicken farm to a great extent by lowering the death toll of chicken raised in the farm. 3. The use of the drug shortened the days to the market, and increased the body weight at the time of marketing. 4. Preventive and therapeutic effects of the liquid enrofloxacin were observed higher than ampicillin, a major antibiotic used in poultry farming. From above results, the liquid form of enrofloxacin would find its use for the prevention and treatment of digestive and respiratory infections, let alone the growth promotion and feed efficiency, especially in the chicken farming practice.

LMC와 RSLMC의 열팽창 특성에 관한 연구

임홍범,최성용,최판길,윤경구 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.A

Latex modification of concrete provides the material with higher flexural strength, as well as high bond strength and reduced water permeability. However, If the thermal expansion properties of overlay concrete (latex-modified concretes) are big different from that of substrate (ordinary portland cement concrete), these would cause a big interfacial stresses and result in premature failure. Therefore, the purposes of this study were to investigate thermal expansion characteristics of latex-modified concrete with cement types. The result of thermal expansion showed the coefficient of thermal expansion of concretes increased with latex inclusion. The coefficient of thermal expansion of RSLMC was a little smaller than that of LMC, which might be due to the finer cement grain, compacter internal, and stiffer properties of concrete. However, the coefficients of LMC and RSLMC were quite similar to that of ordinary cement concrete. Thus, this would not cause an interfacial stresses and will enable to ensure long-term performance of concrete bridge deck overlays.

엔로플록사신 액제의 닭유래 병원세균에 대한 시험관내 항균효과 시험

윤효인,박병권,조준형,정상희,박경환,장범수,김종춘,황윤환,임종환,이내경,박승춘 충남대학교 수의과대학 동물의과학연구소 2000 動物醫科學硏究誌 Vol.8 No.-

In this study the antimicrobial spectrum and sensitivity of a liquid formulation of enrofloxacin against the major six pathogenic bacteria isolated from the diseased poultry in Korea were evaluated in comparison with ciprfloxacin (CFX), gentamicin (GM) and penicillin (PC). A liquid form of enrofloxacin, a test material and ciprofloxacin showed at least 83% antibacterial activity against all of six test pathogenic microorganisms at the fixed concentration of 10 ㎍/㎖. Gentamicin and penicillin revealed much lower antibacterial activity at the same condition. We evaluated the liquid form of enrofloxacin as having widespread antibacterial spectrum against poultry infections. The liquid form of enrofloxacin showed potent antibacterial activity, with the MIC range being 0.12∼2 ㎍/㎖ against Gram positives, 0.06∼2 ㎍/㎖ against Gram negatives and 0.5∼2 ㎍/㎖ against Mycoplasma spp. These values were equivalent to or somewhat higher than those of ciprofloxacin, but much lower than those of gentamicn and penicillin. This new liquid form of enrofloxacin would find its way in application of mixing with drinking water for the prevention and treatment of diverse infections in chickens.

라덱스 혼입률에 따른 철근콘크리트의 휨파괴 거동특성

정원경,김동호,이주형,임홍범,윤경구 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

Reinforced concrete(R/C) is commonly used to structures because they have many merits that compressive strength, economy and so on. However, reinforced concrete has a crack at the tensile section which is due to the relatively lower tensile strength than its compressive strength. Latex modified concrete(LMC) has higher tensile and flexural strength than the ordinary portland cement, due to the interconnections of hydrated cement and aggregates by a film of latex particles. The purpose of this study was to investigate the flexural behavior of reinforced concrete beam with latex modified concrete, having the main experimental variables such as concrete types(ordinary portland cement concrete, latex modified concrete), latex contents(0%, 15%), flexural steel ratios(0.012, 0.0235), and with/without shear reinforcement. The beam of LMC showed considerably higher initial cracking loads and ductility than that of OPC, but, similar to ultimate strength and deflection. This might be attributed to the interlocking of hydrated cement and aggregates by a film of latex particles, water retention due to hydrophobic, and colloidal properties of the latexes resulting in reduced water evaporation. The beam with latex modified concrete could be adopted at field for controlling and reducing the tensile crack due to its higher tensile strength.

라텍스개질 콘크리트의 열팽창 특성 분석

최성용,이주형,임홍범,윤경구 강원대학교 산업기술연구소 2003 産業技術硏究 Vol.23 No.A

The properties of mechanics and durability of LMC have been performed actively. However. little studies on analysis and properties of thermal expansion has been on the temperature variation. Especially. the low of bonding strength and tensile cracking are caused by difference of thermal expansion between LMC and the substrate concrete Therefore, this study focused on effect of thermal expansion behavior and properties of LMC according to temperature variation. To identify the property of thermal expansion of LMC. tests of modulus of thermal expansion were carried out at 28 days after casting specimen. subjected to temperature variation between 10℃ and 60℃ The results of this study showed the modulus of elastic of LMC was similar to that of ordinary portland concrete(OPC) It means that stresses caused by difference of modulus of elastic did not occur on interface between LMC and existing concrete The modulus of thermal expansion of LMC had a little smaller than that of OPC The modulus of thermal expansion of polymer modified concrete is generally larger than OPC. but the result of this test IS disagree with the fact. which may be due to the humidity evaporation difference and aggregate properties

A new in vitro method for evaluating the antimicrobialactivity of toothpaste

Yun Kyong Lim,Joong-Ki Kook 대한구강생물학회 2021 International Journal of Oral Biology Vol.46 No.2

The purpose of this study was to introduce a new in vitro method for evaluating the antimicrobial activity of toothpaste, reflecting the actual toothbrushing time and the dilution of toothpaste by salivation. We designed three experimental groups and one negative control group. The experimental groups were (1) 90 μL of toothpaste + 10 μL 1X phosphate-buffered saline (PBS, 9/10 dilution group), (2) 50 μL of toothpaste + 40 μL 1X PBS (1/2 dilution group), and (3) 25 μL of toothpaste + 65 μL 1X PBS (1/4 dilution group). During toothbrushing, saliva is continuously secreted into the oral cavity and the toothpaste concentration is diluted over time during toothbrushing. Therefore, the 1/2 and 1/4 dilution experimental groups were added. The negative control group was toothpaste diluted 20,000-fold with 1X PBS. Miracle Fresh Doctor toothpaste and Streptococcus mitis KCOM 1350, Prevotella intermedia KCOM 1107, Fusobacterium nucleatum subsp. polymorphum KCOM 1322, and Aggregatibacter actinomycetemcomitans KCOM 1306 were used as the toothpaste and target bacterial strains, respectively. The number of bacterial cells plated on agar plates in the negative control group was 1,000 CFU. If the number of colonies on the experimental group plate was less than one, the treatment was considered to have > 99.9% bactericidal activity. These results suggest that this new in vitro method for antimicrobial evaluation could be used as the standard method for testing the antimicrobial activity of toothpaste.

Antimicrobial effect of Australia propolis on cariogenic and periodontopathic bacteria

Yun Kyong Lim,So Young Yoo,Dae Sung Lee,Joong-Ki Kook 대한구강생물학회 2019 International Journal of Oral Biology Vol.44 No.4

The purpose of this study was to investigate the antimicrobial effects of Australia propolis against cariogenic and periodontopathic bacteria. Antimicrobial activity was determined by evaluating the minimal bactericidal concentration (MBC). Cell cytotoxicity of propolis extract on normal human gingival fibroblast (HGF-1) cells was observed using the methylthiazolyldiphenyl-tetrazolium bromide assay. The data indicated that, with the exception of Aggregatibacter actinomycetemcomitans (KCOM 1306), the MBC values of the propolis strains were 0.25–1% without HGF-1 cell cytotoxicity. These results suggest that propolis can be used to develop oral hygiene products for the prevention of oral infectious disease.

Development of strain-specific polymerase chain reaction primers to detect Fusobacterium hwasookii strains

Yun Kyong Lim,Joong-Ki Kook 대한구강생물학회 2021 International Journal of Oral Biology Vol.46 No.4

This study aimed to develop strain-specific polymerase chain reaction (PCR) primers to detect Fusobacterium hwasookii KCOM 1249T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1256, F. hwasookii KCOM 1258, and F. hwasookii KCOM 1268 on the basis of nucleotide sequences of a gene specific to each strain. The unique genes for each F. hwasookii strain were determined on the basis of their genome sequences using Roary. The strain-specific PCR primers based on each strain-specific gene were designed using PrimerSelect. The specificity of each PCR primer was determined using the genomic DNA of the 5 F. hwasookii strains and 25 strains of oral bacterial species. The detection limit and sensitivity of each strain-specific PCR primer pair were determined using the genomic DNA of each target strain. The results showed that the strain-specific PCR primers correspond to F. hwasookii KCOM 1249T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1258, F. hwasookii KCOM 1256/F. nucleatum subsp. polymorphum KCOM 1260, or F. hwasookii KCOM 1268/Fusobacterium sp. oral taxon 203 were developed. The detection limits of these strain-specific PCR primers ranged from 0.2 to 2 ng of genomic DNA for each target strain. The results suggest that these strain-specific PCR primers are valuable in quality control for detecting specific F. hwasookii strains. gingivalis is a well-established periodontal pathogen, and tissue factor (TF) is a key initiator of the coagulation cascade. In this context, P. gingivalis has been reported to enhance TF expression in human endothelial cells. The present study investigated the underlying mechanisms of TF induction by P. gingivalis in human umbilical vein endothelial cells. P. gingivalis increased TF expression in a dose- and time-dependent manner. Not only live bacteria but also glutaraldehyde-fixed bacteria increased TF expression to the same extent. However, sonicates of P. gingivalis did not induce TF expression. Cytochalasin D and SMIFH2, which are inhibitors of actin polymerization and actin nucleation, respectively, inhibited the TF expression induced by P. gingivalis . Finally, TF production was decreased or increased in the presence of various signaling inhibitors, including mitogen-activated protein kinases. These results suggest that P. gingivalis induces endothelial TF expression by a bacterial internalization-dependent mechanism and through diverse signal transduction mechanisms. solutions. Tertiary dentin is formed when odontoblasts are directly affected by various stimuli. Recent preclinical studies have reported that stimulation of the Wnt/β-catenin signaling pathway could facilitate the formation of reparative dentin and thereby aid in the structural and functional development of the tertiary dentin. A range of signaling pathways, including the Wnt/β-catenin pathway, is activated when dental tissues are damaged and the pulp is exposed. The application of small molecules for dentin regeneration has been suggested as a drug repositioning approach. This study reviews the role of Wnt signaling in tooth formation, particularly dentin formation and dentin regeneration. In addition, the application of the drug repositioning strategy to facilitate the development of new drugs for dentin regeneration has been discussed in this study.

Antimicrobial activity of Garcinia mangostana L. ethanol extract against Cutibacterium acnes and Staphylococcus aureus

Yun Kyong Lim,So Young Yoo,Soon-Nang Park,Dae Sung Lee,Joong-Ki Kook 대한구강생물학회 2019 International Journal of Oral Biology Vol.44 No.3

The purpose of this study was to investigate the antimicrobial activity of the ethanol extract of Garcinia mangostana L. (mangosteen) against Cutibacterium acnes (6 strains) and Staphylococcus aureus (6 strains). The antimicrobial activity of the mangosteen extract was evaluated based on its minimal bactericidal concentration. Cytotoxicity of the mangosteen extract against human embryonic kidney 293 (HEK 293) cells was determined using the cell counting method. The data showed that the mangosteen extract was not toxic to HEK 293 cells at a concentration of up to 16 µg/mL and killed 87.0% and 99.9% of C. acnes and S. aureus after 10 minutes and 1 hour of treatment, respectively. These results suggest that ethanol extract of mangosteen can be used as an anti-acne agent.

알카리성부여제를 사용한 지하구조물의 중성화 회복효과에 관한 실험적 연구

여경윤 ( Yeau Kyong Yun ),김종길 ( Kim Jong Kil ),김문겸 ( Kim Moon Kyum ),임윤묵 ( Lim Yun Mook ) 한국구조물진단유지관리공학회 2001 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.5 No.1

In generally, amount of alkali in cementious material greatly affect the durability of concrete structure. In this study, alkalization recovery effect of carbonated underground structures due to penetrated alkalization agent is investigated. Tests were conducted to investigate the alkali recovery effect on existing underground structures. Various carbonated underground structures, such as sewer system, subway etc., were selected and applied with several finishing materials. Results indicate that the concrete structure covered with cement paste and corrosion inhibitory paste show better alkali recovery effect than that of alkalization agent and repellent paint.