소아의 치면세균막에 존재하는 mutans streptococci의 분포

국중기,박종휘,유소영,김화숙,이난영 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.3

한국인 소아의 치면세균막에 존재하는 mutans streptococci 종 및 생물형의 발현빈도와 치아우식경험지수와 상관관계를 알아보기 위하여. 조선대학교 치과병원에 내원한 12세 미만 113명의 소아 환자의 치아우식경험지수를 구하고, 이들의 상하악 유전치 및 유구치의 협면 및 설면의 치면세균막 샘플을 채취하여 mutans streptococci를 mitis-salivarius bacitracin 배지에서 선택적으로 분리하였다. 이들의 biotype을 알아보기 위해 생화학적 검사를 실하였고, 이들의 종 수준에서의 동정을 위해 dextranase 유전자를 표적으로 하는 중합효소연쇄반응을 시행하여 하였다. 113명의 환자 중에서 40명의 치면세균막에서 40 균주의 mutans streptococci이 검출되었다. 이들 중 생물형 제 Ⅰ형 (45%)이 가장 많이 검출되었으며, 그 다음으로 제Ⅳ형 (32.5%), 제 Ⅱ형 (15%). 제 Ⅴ형 (5%), 제 Ⅲ형 (2.5%) 순으로 검출되었다. 또한, 종 수준에서의 발현빈도를 알아본 결과 S. mutans가 69%, S. sobrinus는 31%였다. Mutans streptococci 종 또는 생물형에 따른 환자의 치아우식경험지수간의 차이는 없는 것으로 조사되었다(p>0.05). 이상의 결과를 종합할 때, 한국인의 소아의 구강 내에 존재하는 mutans streptococci중 생물형 제 Ⅰ형인 S. mutans가 가장 높은 빈도로 존재하며, 치아우식증이 세균학적 요소만이 아닌 기타 여러원인 요소에 의해 발병되는 다는 여러 연구 결과와 일치함을 알 수 있었다. The aim of this study is to survey the frequency of mutans streptococci species and biotypes isolated from dental plaque in Korean children and the relationship between species and biotypes of mutans streptococci and dft index. Dental plaques were collected from the anterior and molar teeth of upper and lower jaws in the subjects, aged below 12 years old. A dental examination was performed for dft (decayed, filed, total) with the WHO caries diagnostic criteria. The mutans streptococci from the sample were cultured selectively on mitis salivarius-bacitracine (MSB) agar plate. For biotyping of mutans streptococci, biochemical test was performed. From the culture, bacterial genomic DNA was prepared f3r using of PCR template for the identification of mutans streptococci at the species-level. Forty strains of mutans streptococci were isolated from dental plagues of 40 patients. The biotype Ⅰ (45%) and biotype Ⅳ (32.5%) were most frequently detected. The prevalence of s. mutans and S. sobrinus was 69% and 31%, respectively There was no positive relationship between species and biotypes of mutans streptococci and dft index. Our results revealed that biotype Ⅰ and S. mutans were frequently detected in Korean children and support that dental caries incidents by many causative factors not only bacterial factor.

교정환자의 브라켓과 치아 경계부에 존재하는 치면세균막내 mutans streptococci 종 및 생물형의 식별

김미애,유소영,김화숙,국중기,임성훈,윤영주,김광원 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.1

본 연구는 교정환자의 브라켓과 치아 경계부 및 브라켓으로부터 2 mm 이상 떨어진 치아 평활면의 치면세근막에 존재하는 mutaus streptococci의 종 및 생물형에 차이가 있는지를 알아보고자 시행되었다. 조선대학교 치과병원에 내원한 13세 이상 35세 미만의 환자 28명으로부터 브라켓을 장착하고 있는 61개 치아에서 치균세균막을 채취하여 mutans streptococci를 MSB 배지에서 선택적으로 분리한 다음, 이들의 지놈 DNA를 추출하여 dextranase 유전자를 표적으로 하는 중합효소연쇄반응법을 시행하고, 그 증폭물을 Hae Ⅲ로 소화하고, 이를 전기영동하여 제한효소절편길이에 따라 그 종을 식별하였다. 또한 생물형을 조사하기 위하여 생화학적 검사를 실시하였다. 그 결과 브라켓과 치아 경계부 및 브라켓으로부터 2 mm 이상 떨어진 평활면의 치면세균막에 존재하는 mutans streptococci 종은 서로 비슷한 검출 빈도를 보이나 두 곳에 존재하는 mutans streptococci 생물형은 서로 차이가 있는 것으로 나타났다. 향후 브라켓과 치아 경계부 및 치아 평활면의 치면세균막의 mutans streptococci 생물형의 차이와 브라켓 주위의 법랑질 탈회 및 치아우식증 발병과의 상관관계에 대한 연구가 필요하다. The aim of this study was to compare the species and biotypes of mutans streptococci isolated from dental plaques sampled from the interfaces between the bracket and tooth surface and smooth tooth surfaces in orthodontic patients. Dental plaque was collected from the interfaces between brackets and teeth (test group), and from smooth tooth surfaces distant from brackets by more than 2 mm (control group). The dental plaque collected by a sterilized curette was transferred into a vial of 1 X PBS. The sample in the vial was vigorously vortexed for1 min and plated on mitissalivarius bacitracin (MSB) agar plate using cotton tips. The agar plates were incubated at 37℃ in a candle jar for 2 days, and again incubated for 1 more day at anambient temperature. Individual colonies were cultured in TH broth at 37℃ CO₂ incubator. The PCR-RFLP based on dextranase gene was performed for the identification of mutans streptococci at the species-level. For biotyping of mutans streptococci, biochemical tests were performed. There was no significant difference of the species of mutans streptococci isolated from both test and control groups. However, the biotypes of the mutans streptococci isolated from test and control groups were different. These results may offer the basic data to verify the relationship between the mutans streptococci biotype and enamel decalcification or dental caries in orthodontic patients with fixed appliances.

이종 재료 접합부의 응력확대계수

김문기,국정한,유중학,성호현 韓國技術敎育大學校 1996 論文集 Vol.3 No.1

In this study, fracture aspects for dissimilar materials welded by right and left or up and down in symmetry are examined by using Finite Element Method(FEM) in case that holes exist at up and down in symmetry for the center of crack, and the results of this study are as follows ; 1. When the strength(E₁) of a material with a center crack is lower than that (E₂) of the dissimilar material which is welded by right and left in symmetry, the crack propagation rate decreases by about 25%, while it increases by about 20% when the E₁ is higher than E₂. 2. When the E₁ is lower than the E₂ which is welded by up and down in symmetry, the crack propagation rate decreases by about 25% while it increases by about 75% when the E₁ is higher than the E₂. 3. The value of K₁/K?? is constant up to 2.0 in which is the ratio (a/R) between crack length and hole radius, and the value is decreased or increased a little above 2.0. It is regarded that a phenomenon of crack closure is applied according to the welded type of dissimilar material. In addition, It is noticed that retardation effect of crack propagation is changed greatly according to the distributed position of dissimilar material.

중합효소연쇄반응법을 이용한 급성 치수 및 치근단 질환의 병원성 세균의 동정

김지훈,유소영,임선아,국중기,임상수,박슬희,황호길 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.2

The purpose of this study was to investigate the frequency of 7 putative pathogens in endodontic infections. The specimens were collected from infected pulpal tissue of patients who were referred for root canal treatment to the department of conservative dentisty, Chosun University. Samples were collected aseptically using a barbed broach and a paper point. The cut barbed broaches and paper points were transferred to an eppendorf tube containing 500 ml of 1 X PBS. DNAs were extracted from the samples by direct DNA extraction method using lysis buffer (0.5% EDTA, 1% Triton X-100). Identification of 7 putative pathogens was performed by PCR based on 16S rDNA. The target species were as follows: Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Bacteroides forsythus, Actinobacillus actinomycetemcomitans, and Treponema denticola. Our data revealed that the prevalence of P.endodontalis was found in 88.6% (39 / 54), P.gingivalis 52.3% (23 / 44), P.nigrescens 18.2%(8 / 44), P.intermedia 15.9% (7 / 44), B.forsythus 18.2% (8 / 44), A.actinomycetemcomitans 2.3% (1 / 44), T.denticola 25% (11 / 44) of the samples. The high prevalence of P. endodontalis and P.gingivalis suggests that they may play an important role in the etiology of endodontic infections.

Penicillium sp.에 依한 α-Galactosidase 生成에 關한 硏究

金鍾國,朴啓仁,愼重燁 경희대학교 부설 식량자원개발연구소 1984 硏究論文集 Vol.5 No.-

The strong α-Galactosidase producing micro-organism was isolated from soil of soybean field and identified as Penicillium janthinellum. The optimum cultural and enzyme condition of P. janthinellum were investigated. The cell growth and enzyme production of P. janthinellum were observed to reach maximum at pH 5.0 in xylose medium and α-Galactosidase of P. janthinellum was produced constitutively. The optimum pH of crude α-Galactosidase was pH 5.0. The optimum temperature of crude α-Galactosidase was 50℃ and the enzyme was inactivated completely at 70℃ in 10 min.

Penicillium sp.에 依한 α-Galactosidase 生成에 關한 硏究

金鍾國,朴啓仁,愼重燁 慶熙大學校 1984 論文集 Vol.13 No.-

The strong α-Galactosidase producing micro-organism was isolated from soil of soybean field and identified as Penicillium janthinellum. The optimum cultural and enzyme condition of P. janthinellum were investigated. The cell growth and enzyme production of P. janthinellum were observed to reach maximum at pH 5.0 in xylose medium and α-Galactosidase of P. janthinellum was produced constitutively. The optimum pH of crude α-Galactosidase was pH 5.0 The optimum temperature of crude α-Galactosidase was 50℃ and the enzyme was inactivated completely at 70℃ in 10 min.

TiAIN 코팅 평 엔드밀의 성능평가에 관한 기초 연구

유중학,국정한,김문기 한국공작기계학회 2001 한국생산제조학회지 Vol.10 No.5

The purpose of this study is an evaluation of flat end mills to develop appropriate tools for the high speed machining. First of all, several flat end mills which are produced by different markers are selected to analyze the performances of the tools. Experimental works are also executed to measure cutting force, tool wear and surface roughness for different cutting conditions. And then the results are compared and analyzed for developing optimal cutting tool in the high speed condition.

Bifidobacterium angulatum KCTC3236의 α-galactosidase에 의한 Oligo당 생성의 최적조건

왕지원,김경민,강대중,강국희,정재록 성균관대학교 생명과학자원연구소 1995 生命資源科學硏究 Vol.2 No.1

Bifidobacterium angulatum KCTC3236 showed the highest α-galactosidase activity among the tested strains of Bifidobacteria( data not shown). Optimum culture conditions for the maximum production of α-galactosidase were as follows. The culture media was MRS broth containing 1% galactose as a carbon source and its initial pH was 7.0. The incubation temperature and time were 37℃, 21 hours respectively. Melibiose have been used as substrate. The formation of oligosaccharides was maximum at 40℃ when the substrate concentration was 30%. And the unit of α-galactosidase was 40 unit. Finally, we could observe the maximum production of oligosaccharides after 14 hours' enzyme reaction.

기능성 소화불량증환자에서 Winstal® 투여에 관한 임상경험

이창형,김영탁,금민수,권중구,안병철,윤영미,권영오,김성국,최용환,정준모 慶北大學校 醫科大學 1994 慶北醫大誌 Vol.35 No.3

목적 : 기능성 소화불량증은 소화, 흡수등 장관의 기능적인 이상과 관련되어 있을 것으로 생각되며 복합소화효소제(Winstal®)를 투여하여 그 임상효과를 평가하고자 본 연구를 실시하였다. 대상 및 방법 : 1994년 3월 부터 6월까지 경북대학교병원 내과를 방문한 기능성 소화불량증을 호소하는 환자 20명을 대상으로 Winstal®을 1회 1정씩, 1일 3회 식후 30분내에 경구로 2주간 투여하였다. 결과 : 소화불량증의 증상은 복부불쾌감, 복부팽만감, 식욕부진 및 오심, 복부동통, 공기연하증, 고창 및 구토순이었으며, 증상의 개선은 복부불쾌감이 76.4%(13/17)로 가장 높았으며, 그 다음으로 복부팽만감 및 공기연하증이 66.5%(10/15, 6/9)이었고, 오심 61.5%(8/13), 식욕부진 53.8%(7/13), 복부동통 41.6%(5/12), 고창 37.5%(3/8)이었다. 각 환자별 종합적인 증상의 개선도는 현저한 개선이 2예(10%), 중등도 개선이 3예(15%), 약간개선이 11예(55%), 불변이 4예(20%)이었으며 종합적인 유효율은 80%(16/20)이었다. 부작용은 한 예에서도 관찰되지 않았다. 결론 : 본 제제는 기능성 소화불량증 환자의 증상개선에 추천할 만한 유효한 약제로 생각된다. Dyspepsia is a common symptom in gastroenterologic practice and trigger for numerous consultations with physician. The treatment of chronic functional dyspesia is unsatisfactory. This study was performed to evaluate the efficacy of the digestive compound (Winstal®) on 20 functional dyspepsia patients. On open trial, all patients were given 6 tablets daily for 2 weeks and we evaluated the efficacy of this preparation according to the degree of the improvement. The improvement of symptoms was 76.4%(13/17) in abdominal discomfort, 66.5%(10/15, 6/9) in abdominal distension and aerophagia, 61.5%(8/13) in nausea, 53.8%(7/13) in abdominal pain, and 37.5% (5/12) in flatulence, respectively. Overall effectiveness of subjective symptoms was 80% (16/20) and there were no untoward effects of the preparations during this study. As a result, We think that this preparation is an effective one to relieve symptoms of functional dyspepsia.

수종의 레진 모노머가 우식 유발성 세균의 활성에 미치는 영향

서영주,국중기,윤정훈,김수관,이난영,이상호 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.2

이전의 연구에서 레진 재료를 포함한 여러 수복재료에서의 유출물이 우식 유발 세균의 성장에 영향을 줄 수 있다는 보고가 있었다. 이번 연구의 목적은 대표적인 우식 유발 세균인 Streptococcus mutans와 Streptococcus sobrinus의 성장에 대하여 레진을 구성하는 모노머들(Bis-GMA, TEGDMA, EGDMA, UDMA, HEMA, Camphoroquinone)이 어떠한 영향을 줄 수 있는지에 대하여 알아보고자 하는 것이다. 결과는 다음과 같다. 1. S. mutans와 S. sorbinus의 성장률은 6가지 레진 모노미 모두에서 0.03 m㏖/L의 농도에 서 유의할 만하게 감소되었다. 2. S. mutans의 성장률은 0.01 m㏖/L 농도의 UDMA의 0.005 m㏖/L, 0.01 m㏖/L 농도의 Camphoroquinone에서 대조군에 비하여 유의할만하게 감소되었다. 3. S. sorbinus의 성장률은 0.01 m㏖/L 농도의 HEMA. UDMA와 0.005 m㏖/L, 0,01 m㏖/L 농도의 Camphoroquinone에서 대조군에 비하여 유의할만하게 감소되었다. 4. S. sorbinus의 성장률은 0.001, 0.01, 0.03 m㏖/L 농도에서 대조군에 비하여 유의할만한 감소를 보였으며 각 실험군들 간에도 통계학적으로 유의할만한 차이를 보였다. 이상의 결과를 종합하면 레진 모노머를 적용한 모든 군에서 적용하지 않은 양성 대조군에 비해 두 세균의 증식률이 감소되었으며, 세균의 성장을 촉진하지 않은 것으로 사료된다. The purpose of this study was to examine the effects of resin composite monomers (Bis-GMA, TEGDMA, EGDMA. UDMA. HEMA, Camphorquinone) on the growth of the two cariogenic bacteria, Streptococcus mutans and Streptococcus sobrinus. We obtained the following results : 1. The growth rate of S. mutans and S. sobrinus was decreased significantly in the group of all composite resin monomer at a concentration of 0.03mmoI/L(P〈0.01). 2. The growth rate of S. mutans in the group of UDMA at a concentration of 0.01 mmol/L and the group of CQ at a concentration of 0.005 mmol/L, 0.01 mmol/L 1%-as decreased significantly compared to the control group(P〈0.01). 3. The growth rate of S. sobrinus in the group of HEMA. UDMA at a concentration of 0.01 mmol/L and the group of CQ at a concentration of 0.005mmol/L. 0.0lmmol/L was decreased significantly compared to the control group(P〈0.01). 4. The growth rate of S. sobrinus in the group of EGDMA at a concentration of 0.001, 0.01. 0.03mmol/L was decreased significantly compared t o the control group (P〈0.01) and were showed to be statistically significant difference between experimental groups(P(0.01).