Production and Characterization of Enzymes Involved in Chitin Catabolic Cascade from a Bacterial Strain Isolated from Soil

( Ji Hyun Lee ),( Jeong In Lee ),( So Yeon Park ),( Yoo Kyeong Jang ),( You Bin Lim ),( Hye Yoon Lee ),( Young Min Jung ),( Hae Chang Lee ),( Jong Hwa Lee ),( Shaheen Amna ),( Jae Kweon Park ) 한국키틴키토산학회 2019 한국키틴키토산학회지 Vol.24 No.1

The present study was aimed to isolate the bacteria producing chitinolytic enzymes including chitin deacetylase (CDA) from soil origin. About 24 bacteria were screened for their chitinolytic enzymes producing ability on the basis of colloidal chitin. Amongst one of the most potent isolates designated to JI-02 was further selected as the most prominent chitinolytic and CDAlike enzyme (CDA-X) producer based on the ability of deacetylation of an artificial substrate pNP-acetamilide. The maximum production of CDA-X in crude enzyme from JI-02 was observed in the presence of 1% colloidal chitin at 37°C and pH 6.4 after 120 h of incubation. Potent enzyme activity of CDA-X was determined toward pNP-acetamilide, demonstrating that optimal pH, temperature and ionic strength of the CDA-X were assessed to be 7.0, 52°C and 125 mM, respectively. Unexpectedly, Nacetylglucosamine (GlcNAc) was not fully converted by the action of CDA-X to glucosamine (GlcN) under the established conditions. Further study on enzyme activity toward chitin-oligosaccharides consisting of multi-N-acetylglucosamine (GlcNAc)n, n=2-5 may be necessary to elucidate the mode of action which requires the minimum size of (GlcNAc)n. However, our data suggest that CDA-X can convert chitin to chitosan with the maximum yield of approximately 0.08g/L during the fermentation of the strain in the presence of chitin. Furthermore, we found that crude enzyme showed the significant chitosanolytic activity. Taken together, our data suggest that the strain JI-02 may be a potential candidate as a particular strain for better understating of chitin catabolic pathway.

진단 기준에 따른 취학전 어린이의 중증 유아기 우식증 유병률 비교

임경욱,이광희,라지영,이동진,안소연,김지영,송지현,김윤희 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.4

연구목적은 중증 유아기 우식증에 대한 두 개의 정의를 진단 기준으로 하였을 때 각 기준에 따른 유병률이 일치하는 정도를알기 위함이었다. 연구대상은 익산시 어린이집 중에서 무작위로 추출한 7개 어린이집의 36개월 이상 71개월 이하 어린이401명 이었다. 치경과 탐침을 사용한 구강검사를 통하여 치아별 우식경험유치면 (dmfs)의 수를 조사하였으며 . 중증 유아기 우식증의 진단 기준은 (1) 상악 전치에 1개 이상의, 와동이 형성된 우식,상실(우식증에 의한), 충전 평활면이 있거나 (2) 우식,상실,충전 치면의 수가 3세는 4개 이상.4세는 5개 이상.5세는 6개 이상인 경우로 하였다. 상악 전치부 우식증에 의한 우식유병률과 우식경험유치면수(dmfs)에 의한 우식유병률은 3세에서 각각 26.7%. 28.9%, 4세에서 각각 32.4%, 30.4%, 5세에서 각각 39.4%, 41.3%, 전체에서 각각 35.4%, 35.9%으로서. 연령별로는 약간의 차이가 있었으나 전체에서는 차이가0.5%로서 거의 일치하였다. 따라서 중증 유아기 우식증의 진단은 두 가지 기준 중에서 어느 하나를 사용하더라도 비슷한 결과가 나을 것이라는 것을 확인할 수 있었다. The purpose of study was to compare the prevalences of severe early childhood cahes(S-ECC) using two different diagnostic criteria. The subjects of this study included 401 preschool children from 36 to 71 months of the randomly selected seven nurseries in Iksan city. Severe early childhood caries was defined as (1) 1 or more cavitated, missing (due to caries), or filled smooth surfaces in primary maxillary anterior teeth or (2) a decayed, missing, or filled score of ≥4 (age 3), ≥5 (age 4), or ≥6 (age 5) surfaces. The prevalence determined by maxillary anterior caries and the prevalence determined by dmfs were 26.7%, 28.9% in 3 years, 32.4%, 30.4% in 4years. 39.4%, 41.3% in 5 years, and 35.4%, 35.9% in all, respectively. The results suggest that the two diag-nostic criteria of the severe early childhood caries yield almost the same results.

RAW 264.7 세포에 대한 중국산 천연 광물성 섬유 TAFMAG의 독성효과

임영,한진구,김지홍,김현욱,김은경,김경아,장황신 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.3

Objectives : This study was designed to evaluate cytotoxicity of TAFMAG, which is a trade name of natural mineral fiber mined and produced in China. Methods : The cytotoxicity of TAFMAG was evaluated by measuring iron content, lipid peroxidation, erythrocyte hemolysis, and cytotoxicity in vitro. These results were compared with the data of chrystotile and wollastonite as a positive and negative control, respectively. Results : There was significant increase of Fenton activity in TAFMAG and chrysotile with dose-response pattern. The iron chelating agent, desferrioxamine, significantly decreased Fenton activity of the particulates except wollastonite. TAFMAG and chrysotile fibers significantly increased malondialdehyde concentration from lipid peroxidation of the red blood cell membrane. In erythrocyte hemolysis test, TAFMAG & chrysotile had stronger effect on erythrocyte hemolysis than wollastonite with the concentration of 1,000g/ml. Furthermore, TAFMAG was more hemolytic than chrysotile with the concentration of 5,000g/ml. There was a significant cytotoxic effect in TAFMAG and chrysotile on RAW cell compared with wollastonite. Conclusions : In vitro study suggested that TAFMAG may have a similar health hazard as usual asbestos.

중등 영어교사의 자질에 대한 학생, 교사, 학부모의 인식 비교 연구

임정완,정지현 大邱大學校 師範大學 附設 敎育硏究所 2010 學校敎育硏究 Vol.5 No.2

본 연구는 우리나라와 같은 영어를 외국어로 배우고 가르치는 상황에서 영어교사에게 요구되는 전문성과 자질에 대한 의견이 학생, 학부모와 교사 간에 어떻게 다른지를 탐구해 보는 것이 주된 목적이었 다. 이 연구를 위하여 국내외의 문헌과 선행연구를 통하여 영어교사의 전문성에 대한 자질을 먼저 살펴 보고, 영어교사와 학부모, 그리고 학생집단의 설문 조사를 통하여 세 집단 간의 영어교사의 자질에 대 한 인식을 분산분석(ANOVA)을 활용하여 비교, 검토하여 하였다. 연구 결과로는 교사의 자질로는 크게 5가지 영역으로 도출되었는데, 언어지식, 수업기술, 태도, 상호작용, 성찰이었고, 이에 대한 세 집단의 인식은 각각 영역마다 다르게 나타났고, 이는 교사와 학부모가 기대하는 영어교사상과 학생집단이 기대 하는 영어교사상은 상이하다는 것을 알 수 있었다. 또한 교사의 자질에 해당하는 각 5가지 하위 영역과 나이별, 성별, 근무 연수별, 영어실력별 상관관계가 있는 지를 조사한 결과, 근무 연수와 수업기술에 따 른 차이가 발견되었으며, 나머지 요인들과는 상관관계가 없는 것으로 밝혀졌다. 근무 연수가 15년에서 20년 미만의 교사들이 ‘수업 기술’의 중요성을 가장 많이 인식하고 있는 반면에 근무 연수가 20년 이상 이 된 교사들은 오히려 그 중요성을 가장 낮게 보고 있었다. 본 논문에 참여한 세 집단의 참여자 수가 적어서 이를 일반화하기에는 무리가 따르지만, 세 집단의 의견에 공통점과 차이점이 어느 영역에서 존 재하는 것을 보여준 것으로 의의가 있다고 본다. The purpose of this study is to investigate the quality of a good secondary teacher of English from the perspectives of students, parents, and teachers. A questionnaire with 29 questions was distributed to 60 high school students, 66 parents, and 61 secondary school teachers. The questionnaire consisted of questions about the knowledge of English language, skills related to teaching, the personality of the teacher, skills related to reflection, and interaction skills. The questionnaire was analyzed by the use of SPSS 17.0. ANOVA and frequency analysis. The findings of the study were as follows: first, there was a similarity in the aspect of skills related to teaching and a difference in the aspect of knowledge of English language among teacher, parent, and student groups. The teachers and the parents had the same opinions and attitudes towards the qualities of a good language teacher, whereas the students had different opinions. Second, the correlation between the quality of a teacher and age, sex, and language ability was found to be not existent, whereas the working years of teachers correlated to the skills related to teaching. On the basis of the results of the study, implications on effective English teaching are presented, and further pedagogical implications and future study directions are suggested.

한국, 미국, 중국 청소년의 의복 행동에 관한 연구

임숙자,이지현,문정미,장춘희 이화여자대학교 생활환경대학 인간생활환경연구소 2002 인간생활환경연구소 논집 Vol.- No.1

The purposes of this study were to determine similarities and diferences in the clothing behavior of Korean, American and Chinese Adolescents. Photographs and questionnaires were conducted for this study and the results are as follows. 1) By analyzing the questionnaire survey, Korean adolescents considered their friends advise more when purchasing clothing while Chinese adolescents depended on their parents. In clothing elements, American adolescents considered attractiveness to other sex more than other two countries. 2) For the Photograph analysis, Many bright and vivid color clothing were seen from Chinese adolescents and dull achromatic colored clothing was noticeable from Koreans. Jeans were favored by all three countries but chino pants were only noticeable from Korean adolescents. Even though it is said 'It is one world ond market', this study shows that it is very important to consider the cultural differences among countries.

석면함유 슬레이트 지붕 물받이 퇴적물 중 석면 섬유 함유율

임지현,한솔민,김현석,신유민,박시은,허정윤,김민영,장봉기 순천향대학교 기초과학연구소 2022 순천향자연과학연구 논문집 Vol.28 No.1,2

This study attempted to determine the degree of asbestos release from the aging slate roof by comparing the asbestos content in the slate roof rain gutter with a colored steel plate (tin plate) over the slate roof. Four slate roof houses located in Haengmok-ri, Asan-si, Chungcheongnam-do, and one house constructed with a colored steel plate on the slate roof were selected to collect the sediment of the roof rain gutter. The asbestos fiber content was calculated by a point counting method using a polarization microscope after pretreatment with conversion treatment and hydrochloric acid treatment. The average asbestos content of the four slate roof rain gutter were 1.89%. However, asbestos was not detected in the Slate covering roof rain gutter, which were constructed on the slate roof. Asbestos fiber content was the highest at 2.89% in the slate roof rain gutter installed in 1976, followed by 2.44% in 1953. From the above results, it is necessary to minimize secondary damage as asbestos fibers released from slate roof houses to the surrounding atmosphere or leaked from slate roofs as rainwater may cause soil pollution and seriously affect residents' health. Although covering with colored steel plates (tin plates) has been shown to prevent the leakage of asbestos fibers to some extent, it is believed that a policy alternative to remove the slate roof as soon as possible is needed to solve the fundamental problem.

놀이학습을 통한 초등 영어교육

임지현 The English Linguistic Science Association of Kore 2000 English Linguistic Science Vol.5 No.-

The purpose of the present article is to provide a good language acquistion as well as fun and relaxation for children through various plays and games. The 7th English Curriculum focused on communicative competence. Primary English Education by performing Games in English Class affects English Language learner's communicative competence. This article presents various making-stuff and game materials for children. However this education has many problems such a lack of materials. This paper holes that children would reinforce their learning in this way. Also, we wish to furnish a lot of playing materials and game information.

갈근(葛根)으로부터 분리된 puerarin의 항당뇨 효과

임현애,임지선,김정상 경북대학교 농업과학기술연구소 2006 慶北大農學誌 Vol.24 No.-

본 연구에서는 갈근 및 그의 주 이소플라본인 puerarin의 활성을 세포수준에서 분석하였다. 먼저 갈근에 함유된 이소플라본의 양을 분석한 결과, puerarin이 총 이소플라본의 90 % 차지하였다. 다음으로는 puerarin의 항당뇨 활성을 검정한 결과 먼저 탄수화물 및 지방소화효소저해활성에 대해서는 거의 미비한 것으로 나타났으나 인슐린 감수성 및 지방세포의 분화의 유도에 대해서는 농도의존적으로 작용하는 것으로 관찰되었다. 따라서 puerarin은 지방조직내로 포도당의흡수를 촉진함으로서 항당뇨 효능을 발휘하는 것으로 추정된다. In this study we evaluated the anti-diabetic potential of Puerariae Radix and its isoflavone (puerarin) by investigating their inhibitory activities against digestive enzymes, α-amylase, α-glucosidase and lipase and effect on glucose uptake and PPAR γ expression. The activities of carbohydrate digestive enzymes were not inhibited by puerarin. Glucose uptake in differentiated adipocytes was stimulated by puerarin. Furthermore, puerarin enhanced the differentiation of preadipocytes as evaluated by triacylglycerol (TG) accumulation, which is specific for differentiated adipocytes. The effect of puerarin on expression of peroxisome proliferator-activated receptor γ (PPAR-γ) gene, which is associated with obesity and dyslipidemia, was examined by both real-time PCR and reverse transcriptase PCR. The study demonstrated that puerarin increased the expression of PPAR-γ. In conclusion, puerarin showed potential to exert anti-diabetic action by enhancing cellular glucose uptake and thereby TG accumulation in adipocyte tissue.

절삭유와 유기용매에 혼합 폭로된 근로자의 피부질환에 관한조사

임현술,김지용,성열오 동국대학교 경주대학 1993 東國論集 Vol.12 No.-

Cutting oils denature keratin, defat the skin and remove water from it, causing dryness, fissures and frank eczematization. Solvents remove the surface lipid film. Therefore the skin barrier is weakened and the absorption of irritant substances are increased. Saturated hydrocarbons from the solvent and paraffin series are stronger irritant than those from the aromatic series. To evaluate the health effects on skin among cutting oil and solvent exposed workers, self-administrative questionnaire survey was performed on 72 exposed workers and 91 non-exposed workers. The dermatologic examination and patch test were performed on the workers with suspected skin diseases. The results are summarized as follows ; The prevalences of some dermatologic disorders, such as primary irritant dermatitis, dyshidrotic eczema, allergic contact dermatitis and folliculitis were significantly higher among exposed group than non-exposed group(P<0.05). The positive rate of patch test among 16 workers were 6.3% for cutting oil, 18.8% for old solvent, 18.8% for new solventⅠ and 6.3% for new solvent Ⅱ. These results suggest that cutting oil and solvent may be a cause of occupational dermatoses among exposed workers.

모 대학병원 입원환자의 직업력 기록에 관한 조사

임현술,김지용,정철 동국대학교 경주대학 1998 東國論集 Vol.17 No.2

From January 9, to January 27, 1996, we surveyed medical records for the occupational history of 352 admitted patients in university hospital located in Pohang city. Also, we interviewed the study subjects about their occupational histories to search for occupational related cases. The results obtained are as follows. The number of males were 205 cases and the number of females were 147 cases. The age and sex distributions of study subjects were not significant (p>0.05). Internal medicine (50.3%), orthopaedics (19.6%), general surgery (8.8%), neurosurgery (5.7%) and obstetrics & gynecology (3.7%) were the major admitted departments of the study subjects. The records of occupational history by doctors were only 9 cases (2.6%) but by nurses were 197 cases (56.0%). And then, there were no detailed descriptions for occupations by doctors and nurses. We would suspect that 18 cases (5.1%) were related to the occupations, of which 13 cases (3.7%) were in occupational injuries and 5 cases (1.4%) were in occupational diseases. It should be emphasized in medical education that the occupational and environmental histories were thoroughly investigated to make a correct diagnosis and appropriate treatment and that the standard forms for occupational history taking should be developed.