Quantitative comparison of mRNA expression of glucosyltransferase(GTF) between xylitol-resistant(X^(R)) and xylitol-sensitive(X^(s)) mutans streptococci

Kim, Chong-Chul,Lee, Mi-Na,Kim, Young-Jae,Lee, Sung-Hoon 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.1

Since the long-term exposure of mutans streptococci to xylitol is known to select for xylitol-resistant(X^(R)) natural mutants, the occurrence and survival of such X^(R) strains were performed in batch culture methods. The aim of the study was to compare the differentiation and quantification of mRNA expression of the gtf genes of X^(R) and X^(S) mutans streptococci. Using a real-time reverse-transcription polymerase chain reaction, the expression of each gtf was determined. In X^(R) strains, the relative levels of transcription of gtfB and gtfC were decreased while that of gtfD was increased, suggesting the presence of independent promoters. It also suggested that mutation related to production of glucosyltransferase occurred under the exposure of xylitol could explain the caries-preventive mechanisms of xylitol. 자일리톨에 장기간 노출된 mutans streptococci는 자일리톨에 내성이 발현되어 자일리톨 내성균주가 생성된다고 알려져 있다. 본 연구의 목적은 mutans streptococci에서 자일리톨 내성균주와 감성균주의 gtf 유전자 발현량을 각각의 유전자별로 정량적으로 분석하고 비교하는 것이다. 실시간 역전사 중합효소연쇄반응법을 이용하여 각각의 gtf 발현을 조사한 결과 gtfD는 증가한 반면. gtfB와 gtfC는 감소하였는데 이는 각 유전자의 독립된 조절기전이 존재함을 보여주는 것이다. 또한 자일리톨에 노출된 mutans streptococci에서의 glucosyltransferase와 연관된 유전자변형이 자일리톨의 치아우식증 예방효과의 작용기전 중 하나임을 알 수 있었다.

Effects of Extrusion Conditions on Pasting Properties of Potato and Potato : Wheat Flour Mixture

Cha, Jae Yoon,Cho, Yong-Jin,Kim, Chong-Tai,Kim, Chul-Jin,Ng, P. K. W. 한국산업식품공학회 2003 산업 식품공학 Vol.7 No.2

The purpose of this study was to develop extrusion process of fresh potato and to study the effects of extrusion condition on the pasting properties of extruded potato products. The blend of pressed potato and wheat flour and pressed potatoes were extruded at different die exit temperatures (110-160℃) and screw speed of 100 rpm using a twin-screw extruder with conveying, high and low shear screw configuration. The viscosity-related parameters, such as peak viscosity, through, final viscosity, peak time, and pasting temperature of the feed materials and extruded products, were studied using a rapid visco analyzer (RVA). Their water solubility index (WSI) and water absorption index (WAI) were also studied. The peak viscosity, through, final viscosity, and peak time of pressed potato extrudates and potato-wheat flour mixture extrudates decreased as die exit temperature increased. The WSI and WAI of potato products increased as die exit temperature increased. When high shear screw configuration was used, the values of viscosity-related parameters were lower than those when low shear screw configuration was used. The potato-wheat flour mixture products obtained different degrees of depolymerization from fresh potatoes and wheat flour depending on die exit temperature and screw configuration.

Ciprofloxacin 제제의 생물학적 동등성에 관한 연구

최철희,신재국,신완균,유호진,이경훈,정원석,장인진,신상구 대한화학요법학회 1991 대한화학요법학회지 Vol.9 No.1

국내 시판중인 ciprofloxacin 제제인 Citopcin®(250㎎ tablet)의 동등성을 검토하기 위해 제조원인 Bayer사의 Citopcin®(250㎎ tablet)를 기준제제로 하여 18명의 건강한 남성 피험자를 대상으로 500㎎ 1회 교차 경구 투여후 약동학적 성상을 분석비교한 결과는 다음과 같다. 시험제제의 생체 이용율의 지표인 AUC, C_(mao), T_(max) 및 MRT들의 평균치는 백분율차이에 있어 모든 기준제제 지표의 ± 20% 이내였으며, 이들 생체 이용율 지표들은 분산분석 검정에서 차이를 인지할 수 없었다.생체 이용율 지표들의 기준제제에 대한 백분율 90% 대칭 신뢰구간 검토시 모든 경수들에서 ± 20% 이내의 조건을 만족하였으며 AUC의 경우에는 대칭형 신뢰구간으로 변환시 95% 신뢰구간에서도 동등성의 조건을 만족하였다, 이상의 시험결과로 시험제제인 Citopcin®은 기준제제인 Ciprobay®와 생물학적 동등한 제제로 판단되었다. The pharmacokinetics of ciprofloxacin was studied for the evaluation of the bioequivalence of the generic ciproflocacin products. Two single doses of 500㎎ each of ciprofloxacin(Ciprobay® 250㎎ tablet as a reference compound and Citopcin® 250㎎ tablet s a test compound) were administered orally to ighteen male volunteers in a balanced, randomized crossover design. Pek plasma levels of ciprofloxacin were observed about 1 hour after the doses and the peak concentrations of both products were similar(Ciprobay®, 3.18㎍/㎖; Citopcin®, 2.89㎍/㎖). The values of other pharmacokinetic parameter of ciprofloxacin computed for Ciprobay® are presented in that order: AUC=13.53:12.47㎍·h/㎖, T_(max)=1.28:1.14 hours; MRT=5.30:5.08 hours; t_(1/2)β=3.65:3.47 hours. No satistically significant, differences were detected when AUC and the other parameters were compared with the method of ANOVA. Using the criteria of 90% confidence interval for the assessment of bioequivalence al the parameters were acceptable. The products were found to be equivalent on the premise that no significant difference was detected when the relevant pharmacokinetic parameters were compared, and the confidence limit analysis showed acceptable results.

하이드록시프로필화 찹쌀 전분의 이화학적 성질 및 유과제조 특성

유철,최현욱,김종태,김동섭,최성원,박영준,백무열 경희대학교식량자원개발연구소 2007 硏究論文集 Vol.26 No.1

꾸지뽕나무의 揷木時期, 床土 및 發根劑가 揷木繁殖에 미치는 影響

추갑철,조현서,이총규,이덕철 진주산업대학교 농업기술연구소 2007 農業技術硏究所報 Vol.20 No.-

This study was carried out to develop mass propagation techniques by cutting seedling of Cudrania tricuspidata which is a promising species as a medicinal herbs and a health food trees. Rooting and, mortality rates (percentage of dead cutting) and the number of roots were measured by cutting times, using various growth media and the digesting times of growth hormone. 1. Rooting rates by cutting times were higher in March cutting (64.5%) than in July cutting (55.3%). The highest rooting rates were observed in March cutting (68.5%) with the growth media of peatmoss + perlite. The rooting rates by the digesting times of growth hormone were the highest (87.5%) in 30 hours at IBA 100ppm among the treatments. 2. Callus formation from cutting roots was not related to cutting times and digesting time of growth hormone, but related to growth media. 3. Mortality rates was related to cutting time and digesting time at IBA 100ppm. 4. Number of roots were about 16 and not related to cutting times, growth media and the digesting time of growth hormone. In conclusion, the best techniques for cutting propagations of Cudrania tricuspidata were observed in March cutting (rooting rates : 87.5%) in the growth media of peatmoss + perlite with 30 hours digesting times at IBA 100ppm.

유치원 및 어린이집 아동의 우유병우식증에 관한 연구

김종철 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.3

To investigate the prevalence and etiologic factors of nursing caries, oral examination was performed on 1.100 kindergarten children from 6 seoul areas and 3 Hongchun areas. Parents were asked to fill out questionnaires. The following results were obtained: 1. The prevalence of nursing caries among 1,100 in the sample group (age 30-75 months) was 14.8%. 2. Fathers' education level(p<0.05), mothers' education level (p<0.01) and monthly income was higher in caries-free group children. 3. When the dietary tendencies of nursing caries group and caries-free group were compared. no significant differences in the length and method of feeding were found. However, nursing caries group showed higher frequency of bedtime nursing habit (p<0.01), daytime use of bottle as a comforter(p<0.01) and other beverage feeding in addition to milk (p<0.01). 4. When the parents' awareness of caries prevention was compared. caries-free group performed more frequent tooth cleansing(p0.05) and periodic dental examination (p<0.01). 5. Dental caries experience if mothers was significantly lower in the caries free group(p<0.05). From the above results, it can be concluded that deleterious nursing habit gad great effect on developing nursing caries and the incidence of nursing caries was lower among children with parents of higher socioeconomic status.

한국인 연령에 따른 Actinobacillus actinomycetemcomitans의 발현빈도 및 항체 역가에 관한 연구

정종평,김강주,이상철,손성희 대한구강생물학회 1988 International Journal of Oral Biology Vol.12 No.2

In order to investigate on the frequency and antibody levels to Actinobacillus actinomycetemcomitans from Korean population, normal group were divided into 5 category by the related age : 3-6 years, 7-12 years, 13-20 years, 21-35 years and over 36 years, and also disease group were divided into the diagnostic condition : Localized juvenile periodontitis, post-localized juvenile periodontitis, rapidly progressive periodontitis, adult periodontitis. Each group was composed of 10 to 20 patients and plque sampling was also performed on the mesial pocket of mandibular lst molar with 3 paper points on anaerobic condition. Isolation and identification were done by using a selective medium(tryptic soy agar supplemented with 10% serum, 75ug of Bacitracin and 5ug of Vancomycin per ml) in 10% CO_2 incubator for 3 days with routine Gram staining, biochemical test and colony morphology. Serum antibody levels were also performed with isolated A. actinomycetemcomitans SNUDC 10-1 by using modified ELISA technique. The frequency of A. actinomycetemcomitans in normal healthy group was within 10% and no detection was revealed in 7 years group. Otherwise, the frequency of localized juvenile, rapidly progressive, adult perioduntitis and adult periodontitis associated with diabetes mellitus were 75%, 68%, 42%, and 25%, respectively. Serum IgG antibody levels to A.a SNUDC 10-1 in umbrical cord blood was similar to 3-6 years or 13-20 years group, and 3-6 months group were shown only trace amount of antibody levels. The antibody levels of 1 year and 7-12 years group were revealed 2/4-1/3 levels of 3-6 years group and this levels were gradually increased from 7-12 years group until over 36 years group. However, the antibody levels of localized juvenile, post-localized juvenile and rapidly progressive periodontitis were significantly higher than that of healthy group and no significant differences of the level were recognized between each disease group.

유규치 Ⅱ급 아말감 수복물의 임상적 실패에 대한 연구

김종철,정미영 大韓小兒齒科學會 1992 大韓小兒齒科學會誌 Vol.19 No.1

The frequency and mode of failures of primary molar class Ⅱ amalgam restorations were evaluated. 326 class Ⅱ amalgam restorations in the mouths of childhood patients who presented themselves for dental treatment were examined by visual and tactile inspection. The results were as follows: 1. The frequency of failrues accounted for 53.7% of total number of fillings examined. 2. Improper cavity preparation was found to be the most common factor in failed class Ⅱ amalgam restoration(52.0%). 3. The leading mode of failures was isthmus fracture or missing of the filling(44.0%), followed by marginal ditching, secondary caries, pulp involvement, and tooth fracture. 4. The most common factor contributing to isthmus fracture or missing was improper cavity preparation(67.5%), and occlusal trauma causing it in a lesser number of restorations. The case in which the contributing factor was not found, accounted for 24.7%.

MEAW를 이용한 Angel씨 제III급 부정교합자의 치험례

김종철,최종학 大韓小兒齒科學會 1992 大韓小兒齒科學會誌 Vol.19 No.2

Class Ⅲ malocclusion is more common problem in the Oriental. Their chief complaints are mandibular prognathism, deficient mastication, and esthetic problem. Early C1 Ⅲ malocclusion treatment is necessary for normal function reconstruction. This report presents a case with mandibular prognathism that was treated by means of Fixed edgewise appliance and MEAW mechanics. Class Ⅲ MEAS mechanics is composed of upper ideal archwire, lower multiloop archwire(MEAW), and intermaxillary elastics. After 10 months active treatment, a good ClassⅠmolar relationship was obtained.

中風言語障碍의 治療에 對한 文獻的 考察

張鍾喆 大田大學校 1982 論文集 Vol.1 No.1