국내 살모넬라 분리주에서 spvR 유전자 분포와 단일 뉴클레오티드 다형 연구

권혁준,박경윤,박주연,박용호,김선중,유한상 대한감염학회 2004 감염과 화학요법 Vol.36 No.6

목적 : 지금까지 병원성 살모넬라를 확인하기 위해 분자량이 큰 플라스미드의 존재 유무를 확인하여 왔으나 살모넬라 혈청형 및 검출 방법에 따라 양성율에 큰 차이를 보이고 있고, 일부 병원성 살모넬라 분리주에서 병원성 플라스미드가 관찰되지 않아 spv 유전자들의 유무에 대한 아른 확인방법이 필요하다. 본 실험은 국내 동물 유래 주요 살모넬라 혈청형에서 spvR 유전자의 분포를 알아보고, 병원성 살모넬라 분자진단을 위한 분자표지로써의 가치를 평가하기 위해 실행하였다. 재료 및 방법 : 국내 가축 유래 S. lyphimurium (ST, 26주), S. enteritidis (SE, 10주), S. pullorum (SP, 40주), S. gallinarum (SG, 53주)에 대해 GenBank에 등록된 ST, SE, SP의 spvR 유전자를 비교하여 ST와 SE 간에 차이를 보이는 single nucleotide polymorphism (SNP, 625번 뉴클레오티드)을 포함하도록 시발자를 합성하여 집락-PCR을 수행하였다. 증폭 산물(194bp)은 자동 염기서열장치를 이용하여 염기서열을 결정하였고, 제한효소인 MseI을 사용하여 PCR-RFLP를 실시하였다. 결과 : 집락-중합효소연쇄반응 결과 SP, SG, SE의 모든 (100%) 분리주에서 특이 증폭산물이 검출되었으나 ST의 경우 19주(73%)에서만 증폭되었다. 특히 병원성 관련 플라스미드가 관찰되지 않았던 SP 4주에서 특이적인 증폭산물이 검출되었다. 염기서열 분석결과 SE, SG, SP는 625번 뉴클레오티드에 아데닌을, ST는 구아닌을 가지고 있어 PCR-RFLP를 이용하여 쉽게 구분할 수 있었다. 결 론 : spvR에 대한 집락-중합효소연쇄 반응법은 병원성 플라스미드 검출법보다 SE, SP, SG 병원성 주를 신속하게 검출하는데 유용하고, 625번 뉴클레오티드의 SNP는 ST와 SE, SG, SP를 구분하는 분자표지로 사용될 수 있을 것으로 기대되며, ST에 비해 SE는 진화적으로 SG와 SP에 가까운 것으로 생각되었다. Background : The Salmonella virulence plasmid (spv) genes (spvR, A, B, C and D) on the large virulence plasmids of pathogenic Salmonella serotypes can replace the virulence of the whole plasmid. Recently, virulence plasmid-negative pathogenic Salmonella isolates were isolated. However, positive rates of spv genes among Korean Salmonella serotypes have been obscure. spv genes are conserved in compared to other virulence genes but there are single nucleotide polymorphisms (SNPs) conserved in only certain serotype. Such SNPs are useful for differentiation and understanding evolution of certain serotypes. Materials and Methods : Salmonella serotypes isolated from live stocks [Salmonella typhimurium (ST, 26), S. enteritidis (SE, 10), S. gallinarum (SG, 40) and S. pullorum (SP, 53)] were used for colony-PCR. A primer set covering single nucleotide polymorphism (SNP) at 625th nucleotide of spvR was designed. The nucleotide sequences of amplicons were determined by cyclic sequencing method and RFLP was performed by using MseI. Results : All isolates of SE, SG and SP, including four plasmid-negative isolates, showed specific amplicons but not all of ST (19/26, 73%) were positive to spvR. Based on the nucleotide sequence of 625th nucleotide and PCR-RFLP, SE, SG and SP [A(625)] and ST [G(625)] could be differentiated. Conclusion : spvR can be used as a molecular marker to detect virulent SE, SG, SP and the SNP may be useful for differentiation of SE, SG, SP and ST. According to the SNP study SE may be evolutionarily closer to SG and SP than ST.

문학교재 읽기와 쓰기의 통합적 지도 방안

권혁준 한국교원대학교 한국어문교육연구소 1997 한국어문교육 Vol.6 No.-

Bainite 球狀黑鉛鑄鐵의 磨滅特性에 미치는 殘留Mg의 影響

權赫茂,朴相俊,金水泳 충남대학교 공업교육연구소 1982 論文集 Vol.5 No.2

Bainite spheroidal graphite cast iron specimens of 0∼0.054wt % residual Mg were casted into a green sand mold, 25 mm thickness Y-block. The microstuctures of the castings were studied for mechanical properties and abrasion characteristics. The results obtained from this study are summerized as follows: 1) Under the present expermental conditions, the relation between the abrasion speed and the abraded amount are; 0.5m/sec for 1^st abrasive wear and 2.38m/sec for 2^nd abrasive wear. 2) Increasing the residual Mg, the first abrasion speed for 2nd abrasive wear moved to the low abrasion speed. 3) The maximum amount of abraded material during 2^nd abrasive wear decreases with the increasing residual Mg content, and moves to the high abrasion speed as the residual Mg is increased over 0.042 wt %. 4) The amount of abraded materials increases with the decreasing residual Mg at abrasion speed 2.38 m/sec and with the increasing residual Mg at abrasion speed 0.62∼1.14 m/sec. 5) Increasing the abrasion speed, abrasion mechanisms are as follows; ⓐ 1^st abrasive wear ⓑ 1^st corrosive wear ⓒ 2^nd abrasive wear ⓓ 2^nd corrosive wear. But, Under the present expermental condition the adhesive wear mechanism didn't appear.

Flowable Composite Resin의 미세변연누출 및 전단결합강도

박성준,오명환,김오영,이광원,엄정문,권혁춘,손호현 대한치과보존학회 2001 Restorative Dentistry & Endodontics Vol.26 No.4

배양골세포 이식이 치조골재생에 미치는 영향

정순준,허익,박준봉,이만섭,권영혁 慶熙大學校 齒科大學 1995 慶熙齒大論文集 Vol.17 No.2

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium (30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride (1:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft diet(Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachment the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cell-inoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on Abe both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replaniineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3 mm in diameter and 3 mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 0.1% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 2.5% Glutaldehyde and decalcified with Planko-Rycho Solution for 72 hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in Bum thickness of tissue was done and stained with Hematoxylin-Eosin. All the specimens were observed under the light microscopy. The following results were obtained. 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of, defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

상온재생 유화아스팔트 개질 혼합물의 배합방법 및 특성에 관한 실험적 연구

박승범,권혁준,이봉춘,김선용 충남대학교 산업기술연구소 1999 산업기술연구논문집 Vol.14 No.2

Recently, the quantities of waste asphalt concrete at construction sites have much increased greatly, but maintaining a filling-up and final disposal place is a difficult problem. Therefore, we are faced with a worsening environmental problem brought about present illegal measures. One of the most effective recycling method is cold recycling. This method will satisfies treatment and recycling of construction waste is a very important question in the preservation of environmental and natural resources. So, in this paper, we dealt cold recycling modified mixtures using emulsified asphalt to concern the effect of adding reclaimed asphalt concrete 30, 40, 50%, and using SBR Latex for modified mixtures.

섬유보강 포러스 콘코리트의 물리·역학적 특성에 관한 실험적 연구

조광연,권혁준 공주영상정보대학 2002 논문집 Vol.9 No.-

섬유보강 포러스콘크리트의 공극률과 투수계수의 특성을 분석한 결과는 다음과 같다. 가) 포러스 콘크리트에 2종의 섬유(SF, PF)를 혼입 한 후 혼입률별, 페이스트골재비별 공극률의 실험결과 페이스트골재비가 증가할수록 공극률이 감소하는 경향을 나타내었으며, 또한 동일한 페이스트골재비에서 섬유혼입률이 증가할수록 공극률은 증가하는 것으로 나타났다. 그러나 과다한 섬유혼입은 공극률은 증가시켜 역학적 성능과 내구성 성능을 저하시킬 우려가 있으므로 강섬유는 0.5 vol% 이내, 폴리프로필렌섬유는 0.27 vol%로 이내로 혼입하는 것이 바람직하다고 사료된다. 나) 섬유보강 포러스콘크리트의 투수계수 시험결과 페이스트골재비가 증가할수록 투수계수는 현저히 감소하는 경향을 나타내었으며 동일한 페이스트골재비에서 섬유혼입량이 증가할수록 투수계수는 증가하는 경향을 나타내었다. 따라서 공극률과 마찬가지로 섬유보강 포러스 콘크리트의 투수계수는 섬유혼입량과 페이스트골재비에 영향을 받는 것으로 판단된다. 다) 섬유보강 포러스콘크러트의 압축강도특성은 페이스트 골재비가 증가함에 따라 압축강도는 현저히 증가하는 경향을 나타내었으며 동일한 페이스트 골재비에서는 섬유혼입률이 증가할수록 압축강도는 감소하는 경향을 나타났는데 이는 공극률에 영향을 받았기 때문이라고 판단된다. 또한 전반적으로 섬유의 혼입량이 적을 경우 양호한 압축강도를 나타내고 있으며 섬유를 혼입하지 않은 포러스콘크리트와 비교해보면 강도의 큰 차이는 보이고 있지 않아 섬유의 혼입에 의해 압축강도의 증진효과는 미비한 것으로 나타났다. 라) 섬유를 혼입한 투수론크리트의 인장강도 및 휨강도는 보통 투수콘크리트보다 양호한 증진효과를 나타내었으며, 인장강도는 보통의 투수콘크리트에 비해 강섬유는 5.8∼13.7%, PP섬유는 4.5∼10.8%의 증진효과를 나타내었다. 또한, 휨강도의 경우 강섬유는 15.5∼21.9%, PP섬유는 13.7∼19.7%의 휨강도 증진효과를 나타내었다. 따라서 섬유보강 투수콘크리트는 일반적인 섬유보강 콘크리트에서와 마찬가지로 압축강도의 증진효과보다는 인장력의 효과를 발휘하고 있는 것으로 나타났다. 마) 섬유를 보강한 투수콘크리트의 처짐변형성능을 분석한 결과 섬유혼입에 의해 변형성능이 개선되고 있는 것으로 나타났으며, 보통의 투수콘크리트보다 강섬유는 9.7∼12.9kgf/㎠, PP섬유의 경우는2.9∼5.6kgf/㎠의 휨인성계수 증가를 나타내었다.

백서 골수세포의 석회화 과장에 미치는 치은 섬유아세포의 영향

김석용,권영혁,박준봉 慶熙大學校 齒科大學 1995 慶熙齒大論文集 Vol.17 No.1

The purpose of this study was performed to investigate the mineralization and differentiation of osteobalsts for bone regeneration in vitro and the effect of rate of the composition in periodontal cells on mineralization. For this study, healthy gingival tissues were surgically obtained from the patients during 1st premolar extraction for the purposes of orthodontic treament. Gingival tissue was washed several time with Phosphate buffered saline contained high concentration of antibiotics and antifungal agent, and cultured in Dulbecco's Modified Eagle's Medium(DMEM, Gibco, U.S.A.) Every cell were cultured in state at 37 C, 100% of humidity, 5% of CO2 incubator. Bone marrow stromal cells were isolated from 5-day-old rat femur with using medium irrigation mathod by syringe. Cell suspension medium were centrifuged at 1500 rpm for 5 min and then cultured in the petri dish. Two kinds of cell were freezed and stocked in the liquid nitrogen tank until experiment. Cell were incubated into the 24multi-well plate with 5 x 104 cell/well of medium at 37 ° C, 100% of humidity 5% CO2 incubator for 24 hours. After discarded of the supernatent of medium, 0.5m of medium were reapplied and incubated. And counted the number of cell using the hemocytometer and inverted light microscope. We have measured the number of mineralized nodule with using Alizarin red S. staining in microscope; Furthermore every cell were observed the morphological change between every rate of co-culture of the two kinds of cell. The results were as follows; The rate of proliferation of co-culture cell revealed high rate tendency compared the bone marrow stromal cell only and low growth rate to compared with gingival fibroblast only. The tendency of formation of the mineralized nodule were observed dose-depend pattern of bone marrow stromal cell. It is concluded that the gingival fibroblast may inhibit the formation of mineralized nodule in the culture of the bone marrow stromal cell.

티타늄 표면에 대한 배양 골수세포와 치은 섬유아세포의 생체적합성

오충영,박준봉,권영혁,이만섭 慶熙大學校 齒科大學 1995 慶熙齒大論文集 Vol.17 No.2

The purpose of this study was to evaluate the response in aspect of attachment and growth rate of osteablasts and human gingival fibroblasts to the commercially pure titanium(CP titanium) and titanium alloy(Ti-6A1-4V) that are used widely as implant materials, and to obtain the basic information to ideal implant materials. In this study, commercially pure titanium in first test group, titanium alloy(Ti-6A1-4V) in second test group, cobalt-chromemolybdenum alloy(Co-Cr-Mo alloy) in positive control group, and tissue culture polystyrene plate in negative control group were used. The results of this study were as follows. 1. Bone marrow cells cultured on CP titanium and Ti-6A1-4V showed significantly greater attachment and growth rate(p<0.05) compared to Co-Cr-Mo alloy in each time. 2. There were no significant differences(p>0.05) in attachment and growth rate of bone marrow cells cultured on GP titanium and Ti-6A1-4V or tissue culture plate. 3."Most bone marrow cells cultured on CP titanium, Ti-6A1-4V and tissue culture plate were attached well to each substratum in first 2days, and then, grew at higher growth rate. On the other hand, some cells cultured on Co-Cr-Mo alloy failed to attach in first 2 days, and then, attached cells grew at lower growth rate than other groups. 4. Attachment and growth rates of gingival fibroblasts cultured on CP titanium and Ti-6A1-4V showed no significant differences(p>0.05) compared to Co-Cr-Mo alloy in 2 days, but significantly greater increase(p<0.05) in 5 and 9 days. 5. There were no significantly differences(p>0.05) between growth rates on gingival fibroblasts cultured on CP titanium, Ti-6A1-4V and tissue culture plate in 2 and 5 days, but a significant lower growth rate(p<0.05) on CP titanium and Ti-6A.1-4V versus tissue culture plate. 6. Some gingival fibroblasts cultured on all specimen groups failed to attach, but attached cells grew well especially on CP titanium, Ti-6A1-4V and tissue culture plate. 7. There were no significant differences(p>0.05) between growth rates of both bone marrow cells and gingival fibroblasts cultured on CP titanium and Ti-6A1-4V. As a result of this study, both commercially pure titanium and Ti-6AI-4V showed excellent biocompatibility and there was no significant difference in the cellular response to the both metals. Bone marrow cells cultured on each substratum showed significantly greater growth rate and responded sensitively to cytotoxic effects of metal surfaces compared to gingival fibroblasts. Considering cell response to the substrate, it was likely that the composition itself of titanium metals have no significant effects on the biocompatibility. Further study need to be done to evaluate the influence of surface characteristics on cellular responses.

제 5급와동에서 광중합 그래스 아이오노머 수복물의 미세변연누출에 관한 연구

조인식,박준일,권혁춘 大韓齒科保存學會 1998 Restorative Dentistry & Endodontics Vol.23 No.1

The purpose of this study was to evaluate the microleakage of light cured glass ionomer restorative materials in class 5 cavities. In this in vitro study, class 5 cavities were prepared on buccal and lingual surfaces of forty extracted human premolars and molars on cementum margin. These specimen were randomly divided into four groups of 10 each : Group 1 was Fugi Ⅱ (control), Group 2 was Fugi Ⅱ LC, Group 3 was Vitremer, and Group 4 was Dyract. Group 2 was also divided once more into 2 groups of 5 each : Group 2-1 was pretreated with dentin conditioner and Group 2-2 was not. All teeth were restored according to the manufacturer's instructions. After 500 thermocycling between 5℃ and 55℃, the 40 teeth were placed in 2% Methylene blue dye for 24hr, then rinsed with tab water. The spcimen were embedded in clear resin, then sectioned buccolingually through the center of restoration with a low speed diamond saw. The dye penetration on each of the specimen were then observed with a stereomicroscope at 20. The results of the study were statistically analyzed using the Student-Newman-Keuls Methods and the Mann-Whitney Rank Sum Test. Tooth restorative interfaces were evaluated using SEM analysis. Results were as follows, 1. Compared to conventional glass ionomer restorations, all light cured glass ionomer restorations were fairly resistant to microleakage (P<0.05). 2. Group 3 (Vitremer) and Group 4 (Dyract) were found to be the most resistant, Group 2(Fugi Ⅱ LC) fairly resistant, and Group 1 (Fugi Ⅱ) least resistant to microleakage(P<0.05). 3. No significant differenced were found between Group 2-1 and Group 2-2 (P>0.08). 4. With the backscattered SEM analysis, the degrees to which tight bonding occurred were also observed in all the groups except for Group 1. Group 4 showed the highest degree of tight bonding than any other materials used in this study.