Helicobacter pylori bab Paralog Distribution and Association with cagA, vacA, and homA/B Genotypes in American and South Korean Clinical Isolates

Helicobacter pylori genetic variation is a crucial component of colonization and persistence within the inhospitable niche of the gastric mucosa. As such, numerous H. pylori genes have been shown to vary in terms of presence and genomic location within this pathogen. Among the variable factors, the Bab family of outer membrane proteins (OMPs) has been shown to differ within subsets of strains. To better understand genetic variation among the bab genes and to determine whether this variation differed among isolates obtained from different geographic locations, we characterized the distribution of the Bab family members in 80 American H. pylori clinical isolates (AH) and 80 South Korean H. pylori clinical isolates (KH). Overall, we identified 23 different bab genotypes (19 in AH and 11 in KH), but only 5 occurred in greater than 5 isolates. Regardless of strain origin, a strain in which locus A and locus B were both occupied by a bab gene was the most common (85%); locus C was only occupied in those isolates that carried bab paralog at locus A and B. While the babA/babB/- genotype predominated in the KH (78.8%), no single genotype could account for greater than 40% in the AH collection. In addition to basic genotyping, we also identified associations between bab genotype and well known virulence factors cagA and vacA. Specifically, significant associations between babA at locus A and the cagA EPIYA-ABD motif (P<0.0001) and the vacA s1/i1/m1 allele (P<0.0001) were identified. Log-linear modeling further revealed a three-way association between bab carried at locus A, vacA, and number of OMPs from the HOM family (P<0.002). En masse this study provides a detailed characterization of the bab genotypes from two distinct populations. Our analysis suggests greater variability in the AH, perhaps due to adaptation to a more diverse host population. Furthermore, when considering the presence or absence of both the bab and homA/B paralogs at their given loci and the vacA genotype, an association was observed. Our results highlight the multifactorial nature of H. pylori mediated disease and the importance of considering how the specific combinations of H. pylori virulence genes and their multiple interactions with the host will collectively impact disease progression.ope

Effect of Recombinant CagL Immunization on the Gastric Diseases Induced by Helicobacter pylori in Mongolian gerbils

Helicobacter pylori is an important factor of chronic gastritis, digestive ulcer, and stomach cancer. CagL, a virulence factor of H. pylori, is well-known as a pilus protein which acts as adhesion to host cell and a component of Type 4 secretion system. In this study, we evaluated the protective response of recombinant CagL protein (rCagL) using Mongolian gerbil animal model for H. pylori infection. The cagL gene was cloned from 26695 H. pylori followed by over-expression and purification of the protein in E. coli. Mongolian gerbils were immunized with rCagL protein mixed with aluminum adjuvant via intramuscular injections once a week during 4 weeks. At a week after the last immunization, the Mongolian gerbils were administrated with H. pylori 7.13 strain into the stomach and sacrificed to measure antibody titer on rCagL by ELISA and bacterial colonization in the stomach, and to examine the histopathological changes and cytokine expression at 6 week after challenge. Antibody titers on recombinant protein were significantly increased from a week after the first immunization. There was no significant change of the number of bacterial colony between control group and immunized group. The relative stomach weight was significantly decreased in immunized group, but the significant change of histopathological assessment was not observed in the stomach. Cytokine expression such as IL-1β and KC also was not significantly different between control and immunized groups. These results indicate that rCagL could effectively induce the formation of the specific IgG antibodies. However, bacterial colonization and histopathological lesions could not be inhibited by the immunization in the stomach, indicating not enough protection against H. pylori infection. We consider that along with CagL other adequate antigens could be needed stimulating immune response and inducing protective effects against gastric disease, and also a better adjuvant could be considered.ope

(A) STUDY ON THE QUALITY OF PRESCHOOL TEACHERS EVALUATED BY THE DIRECTORS OF PRESCHOOL INSTITUTIONS

1980년대에 접어들어 우리나라 유아교육은 그 중요성이 국가적인 차원에서 인식되면서 유아교육기관의 수가 급증하게 되었다. 이러한 유아교육의 양적인 증대에 발 맞추어 나아가야 할 것은 유아교육의 질적인 향상이다. 특히 유아교육의 질적 향상에 가장 중요한 요인의 하나가 유아교육의 교사자질문제라고 할 수 있다. 그러므로 유아교사의 자질에 대해 연구해 볼 필요가 있으며, 이러한 필요에 의해서 본 연구는 출발하였다. 본 연구의 목적은 유아교사 양성 교육과정 구성을 위한 기초자료를 제공하는데 있다. 이에 본 연구에서는 문헌연구를 통해서 유아교사자질요인을 알아보고, 그 자질요인을 기초로 하여 유아교사자질을 평가하기 위한 설문지를 만들었다. 설문지는 유아교사자질을 4가지 요인으로 분류하여 평정할 수 있도록 작성하였다. 4가지 요인은 다음과 같다. 1) 인성적 요인 2) 용모 및 몸가짐요인 3) 전문적지식과 기능요인 4) 교직에 대한 태도요인 등이다. 위의 요인 중 1) 과 2) 는 개인적 자질에 관한 요인이며, 3)과 4)는 전문적자질요인에 속한다. 설문지는 원장을 통해서 평가되었다. 원장들은 자신의 유아교육기관에서 근무하는 교사들을 (1) 교사의 학력 (2) 경력 (3) 교사자격증유·무 (4) 지역 ( 서울/지방 ) (5) 교육기관 ( 유치원/새마을유아원 )등으로 나누어 평정하였다. 조사결과는 다음과 같다. 1) 원장들은 전체적 자질요인에서 중상정도의 만족도를 보였다. 2) 4가지 자질요인중에서는 용모 및 몸가짐요인이 가장 높게 평정되었으며, 전문적지식과 기능요인이 가장 낮게 평정되었다. 3) 인성적요인은 교사의 경력에 따라 큰 차이를 나타내었고, 교사의 학력에 따라서도 다소의 차이를 보였다. 교사자격증유·무와 지역( 서울/지방 ) 교육기관( 유치원/새마을유아원 )에 따라서는 차이를 보이지 않았다. 4) 용모 및 몸가짐요인은 교사의 학력, 경력, 교사자격증유·무, 지역( 서울/지방 ), 교육기관( 유치원/새마을유아원 )에 따라서 차이를 보이지 않았다. 5) 전문적지식과 기능요인은 교사의 학력, 경력에 따라서는 큰 차이를 보였고, 교사자격증유·무, 지역( 서울/지방 ), 교육기관( 유치원/새마을유아원)에 따라서도 다소의 차이를 보였다. 6) 교직에 대한 태도요인은 교사의 학력 , 경력에 따라서 큰 차이를 보였고, 교사자격증유·무, 지역( 서울/지방 ), 교육기관(유치원/새마을유아원 )에 따라서는 차이를 보이지 않았다. 위의 분석된 결과를 종합해 볼 때, 현재 우리나라 유아교사들은 전문적자질이 부족되고 있음을 알 수 있다. 그런데 전문적자질은 교사의 학력, 경력에 따라서 큰 차이를 나타냈음을 주목하지 않을 수 없다. 그렇다면 전문적자질은 교사의 학력, 경력에 의해서 어느정도의 수준까지는 향상시킬 수 있음을 예측할 수가 있을 것이다. 따라서 바람직한 유아교사의 자질을 위해서는 현재 부족되고 있는 전문적 측면에서 유아교사를 양성할 수 있도록 교육과정이 구성되어야 될 것이다.;Since the beginning of the 80&amp;apos;s, the importance of preschool education has been recognized on a national level, and with it, the number of preschool institution increased rapidly. What must go. hard in hard, with the numerical increase of these preschool institution is the quality of education they provide. One of the most important aspect in improving the quality of preschool education can be said to lie on teacher&amp;apos;s competency. The purpose of this study is to provide a basic information which can be used in the construction of curriculum for preschool teachers. The traits comprising a competent teacher were determined through literature, and based on these traits a questionnaire was developed to evaluate the competence of the preschool teachers. Specifically, the questionnaire was measuring the effect (1) teacher&amp;apos;s educational background (2) teaching experience (3) teacher&amp;apos;s certificate (4) region (Seoul/other regions) and (5) types of institutions (nursery/kindergarten) has on the following variables; 1) Teacher&amp;apos;s personality 2) Teacher&amp;apos;s manner and posture 3) Professional knowledge and skill 4) Attitudes toward teaching Teacher&amp;apos;s personality, teacher&amp;apos;s manner and posture, professional knowledge and attitudes towards teaching were broadly classified into personal traits and professional traits respectively. And to maintain objectivity, these questionnaires were filled out by the directors of the preschool institutions. The results shown from the questionnaires were as follows: 1. The directors were reasonably satisfied with their teachers. 2. The teachers scored highest on manner and posture, and lowest on professional traits. 3. Personality traits were greatly influenced by teaching experience and somewhat effected by the teacher&amp;apos;s educational background, whether or not the teacher&amp;apos;s certificate, regional factor and types of the institution. 4. Teacher&amp;apos;s manner and attitudes towards teaching were not affected by the teacher&amp;apos;s educational background, experience certification, region, or the types of the institution. 5. Professional knowledge varied quality according to educational background, experience but little by certification, region, and the types of institutions. 6. Teacher&amp;apos;s attitude towards teaching varied by teacher&amp;apos;s educational background but not by certification, region or the types of institutions. These results points to the fact that Korean preschool teachers lack professional knowledge. Furthermore, one can not fail to observe the strong correlation between teacher&amp;apos;s competency and teachers experience and educational level. Consequently, one can assume that improvement of teacher&amp;apos;s professional competency can be brought on through teacher&amp;apos;s education and experience. Thus in conclusion, in order to produce professionally competent teachers development of well-structured teacher training program is seriously called for.목차 = ⅲ 논문개요 = ⅴ Ⅰ. 서론 = 1 A. 연구의 필요성 및 목적 = 1 B. 연구의 문제 = 4 Ⅱ. 이론적 배경 = 5 A. 교사자질의 중요성 = 5 B. 교사자질에 관한 제견해 = 9 C. 유아교사자질의 평가기준 = 17 D. 유아교사 자질의 평정도구 제작 = 21 Ⅲ. 연구의 방법 및 절차 = 24 A. 조사의 설계 = 24 B. 조사대상 = 24 C. 설문지의 구성 = 27 D. 자료수집 방법 및 절차 = 27 E. 자료분석 방법 = 28 F. 연구의 제한점 = 28 Ⅳ. 연구결과 및 논의 = 29 Ⅴ. 요약 및 결론 = 44 A. 요약 = 44 B. 결론 = 47 참고문헌 = 49 부록 = 52 ABSTRACT = 5

Le Pascha dans les tragedies religieuses de J. Racine

학위논문(박사)--서울大學校 大學院 :佛語佛文學科 佛文學專攻,1995.Docto

Geographic diversity in Helicobacter pylori oipA genotype between Korean and United States isolates

Helicobacter pylori outer membrane inflammatory protein A (OipA) was originally named for its role in inducing inflammation in the host, as evidenced by high mucosal IL-8 levels. Expression of OipA is regulated by phase variation of a CT dinucleotide-repeat located in the 5' region of the gene. However, little is known about OipA geographic diversity across isolates. To address this gap, we conducted a large-scale molecular epidemiologic analysis using H. pylori clinical isolates obtained from two geographically distinct populations: Korea and the United States (US). Most Korean isolates (98.7%) possessed two copies of oipA located at two specific loci (A and B) while all US isolates contained only one copy of oipA at locus A. Furthermore, most Korean oipA (94.8%) possessed three or less CT repeats while most US oipA (96.6%) contained five or more CT repeats. Among the two copies, all Korean H. pylori possessed at least one oipA 'on' phase variant while the single copy of oipA in US isolates showed 56.2% 'on' and 43.8% 'off.' Thus, host differences seem to have driven geographic diversification of H. pylori across these populations such that OipA expression in US isolates is still regulated by phase variation with 5 or more CT repeats, while Korean isolates always express OipA; duplication of the oipA combined with a reduction of CT repeats to three or less ensures continued expression. En masse, these findings suggest that diversity in the oipA gene copy number, CT repeats, and phase variation among H. pylori from different populations may confer a benefit in adaptation to particular host populations.restrictio