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.

영아식의 종류에 따른 영아의 철분과 아연의 섭취량 및 혈청 농도 고찰 : a review

현태선,민지영,이혜경 충북대학교 교육 ·생활연구소 생활과학연구센터 2002 생활과학연구논총 Vol.5 No.-

Although breast milk is the best food for infants, there will always remain a need for good substitutes when breastfeeding is not possible. Most of these substitutes are based on cow milk, but soy milk has been used as an alternative. It is necessary to ascertain that rearing infants on these formulas yields results comparable to those obtained by breastfeeding. Absorption of trace elements such as iron and zinc is well known to be higher from breast milk than from cow milk formula while absorption from soy formula is lower than from cow milk formula. The studies on the contents of iron and zinc in breast milk, cow milk formula and soy formula, and the intakes and blood levels of iron and zinc in infants fed breast milk, cow milk formula and soy formula, and the intakes and blood levels of iron and zinc in infants fed breast milk and cow milk formula were reviewd. The contents of iron and zinc in artificial formulas were higher than those in breast milk, and the intakes lf iron and zinc in infants fed cow milk, formula were higher than those in infants fed breast milk, However, the blood levels of iron in infants fed cow milk formula were significantly lower than those in infants fed breast milk, and there was no significant difference in the blood levels of zinc between infants fed cow milk formula and those fed breast milk. No results have been reported on the iron and zinc nutriture in Korean infants fed soy formula. More research should be focused on the potential consequences of excessive intakes of iron and zinc in infants fed soy formula as well as cow milk formula.

손마사지가 허혈성 심질환 환자의 불안에 미치는 효과

현경선,이향련,공송심,윤경자,김현섭,김효남,최지원,김운정 성인간호학회 2001 성인간호학회지 Vol.13 No.2

The purpose of this study was to investigate the effect of a hand massage program on anxiety, vital sign and pain in clients with ischemic heart disease. The design utilized for this stuffy was quail-experimental with a nonequivalent control group non-synchronized design The subjects were fifty-four patients, twenty-eight for the experimental and twenty-six for the control group, who were admitted with ischemic heart diease at a cardiac intensive care unfit in K medical center of K university. This study was carried out from May, 1999 to March, 2000. The level of anxiety and pain measured by Visual Analogue Scale, systolic blood pressure, diastolic blood pressure and pulse rate were measured before and after hand massage, the state of Anxiety was measured by the Spielberger (1970) scale at admission and after hand massage for three days. The collected data were processed by using the SPSS PC program and analyzed using χ2-test and t-test. The result of this study are as follows : 1. The scores of VAS anxiety and State of anxiety of the experimental group were lower than those of the control group. 2. The degree of systolic blond pressure, diastolic blood pressure and pulse rate of the experimental group were lower than that of the control group. 3. The score of VAS pain of the experimental group was lower than that of the control group. The results suggested that hand massage can decrease VAS anxiety, State of anxiety, vital signs and VAS pain of patients who were admitted with ischemic heart disease at cardiac intensive care unit Therefore, It Is proposed that hand massage is an appropriate nursing intervention to relieve anxiety of the patients who were admitted with ischemic heart disease at a cardiac intensive care unit.

개선된 중성염 전해공정을 이용한 모의 방사성금속폐기물의 제염

이지훈,육완이,양호연,하종현 대한방사선 방어학회 2002 방사선방어학회지 Vol.27 No.2

원자력발전소에서 주로 발생되는 금속폐기물인 탄소강을 중성염전해질인 1.7M의 황산나트륨(Na₂SO₄)과 질산나트륨(NaNO₃)을 이용하여 기존전해제염과 개선된 전해제염공정의 비교실험을 수행하였다. 양극은 인코넬, 음극은 티타늄으로 하여 상온에서 1시간동안 반응시켜 금속폐기물 모재의 weight loss, 두께변화, 전해질 내 침전물농도, SEM을 이용하여 제염전후의 금속폐기물 표면의 형상을 분석하였다. 실험결과 개선된 전해제염 적용시 전해질 종류별 전류밀도 변화에 따른 실험에서는 전류밀도가 0.1∼0.6A/cm²으로 증가함에 따라 1.7M의 황산나트륨 적용시 금속폐기물 모재의 두께변화는 0.48±0.005∼67.7±0.02um, 1.7M의 질산나트륨 적용시에는 0.06±0.005∼17.7±0.05로 나타나 같은 전류밀도에서 황산나트륨 적용시 금속폐기물 모재의 표면 제염효율이 더욱 높은 양상을 보였다. 또한 전류밀도 0.3 A/cm² 및 1.7M의 황산나트륨의 조건에서 개선된 전해제염 적용 시 9.8±0.01um의 금속폐기물 두께변화를 보여 기존전해제염 적용시인 3.7±0.03um의 금속폐기물 두께변화보다 2배 이상의 표면 제염효과를 보였다. Conventional and modified electrolytic decontamination experiment were performed in the 1.7 M solution of sodium sulfate and sodium nitrate for decontamination of carbon steel as the simulated metal wastes which have been produced in large amounts from nuclear power plants. Anode and cathode were used as inconel and titanium respectively. The reaction time and temperature were 1 hr and 25℃. The analyses were performed of the characteristics such as weight loss and thickness change of metal waste, suspended solid in electrolyte and SEM observation. In modified electrolyte decontamination system with increased current density ranged from 0.1 to 0.6 A/cm², the metal waste showed thickness changes of 0.48±0.005 to 67.7±0.02um in 1.7 M sodium sulfate and those of 0.06±0.005 to 17.7±0.05um in sodium nitrate. Metal waste in modified electrolyte decontamination system showed the thickness change of 9.8±0.01um while it reacted up to 3.7±0.03um in conventional system with 0.3 A/cm² of current density and 1.7 M sodium sulfate. Decontamination efficiencies of modified electrolytic process are much higher than that of conventional electrolytic process when both are applied to metal waste.

SMA 혼합물의 피로저항성 개선방안 연구

이현종,김현준,최지영,이정훈 강원대학교 부설 석재복합신소재 제품연구센터 2002 석재연 논문집 Vol.7 No.-

국내의 SMA 혼합물 생산시 대부분 일반 아스팔트와 셀룰로오스 섬유만을 사용하여 왔으나, SMA 혼합물의 공용성을 극대화시키기 위해서는 일반 아스팔트 대신 개질 아스팔트를 사용하는 것이 필요한 것으로 판단된다. 본 연구에서는 SMA 혼합물에서 일반 아스팔트 바인더 대신 개질 아스팔트를 사용한 SMA 혼합물에 대한 실내실험을 실시하여 SBS 개질 SMA 혼합물의 실내 공용성을 평가하였다. 실내시험결과 개질 SMA 혼합물의 피로수명이 일반혼합물에 비해 약 10배 이상 증가하였으며, 휠트래킹 시험을 통한 소성변형 저항성은 개질 SMA 혼합물이 일반 혼합물에 비해 약 3배정도 큰 것으로 나타났다. 또한 접착인장강도는 개질 혼합물이 일반 혼합물에 비해 21∼48% 높게 나타났으며, 저온휨시험 역시 개질 혼합물이 일반 혼합물에 비해 22∼38% 높게 나타났다. 수분손상시험에서는 개질 혼합물은 모두 기준에 만족한 반면, 일반 혼합물은 모두 기준을 만족하지 못한 결과를 나타내었다. 따라서 전체적으로 일반 아스팔트 혼합물에 비해 SBS 개질 SMA 아스팔트 혼합물의 실내 공용성이 뛰어난 것으로 평가되었다. In general, SMA mixes in Korea use unmodified asphalt binder and cellulose fiber. To increase the performance of the SMA mixes, it seems to be necessary to use modified asphalt binders. In this study, the laboratory performance of SBS modified SMA mixes instead of using conventional unmodified asphalt binder was evaluated. Uniaxial tensile fatigue test results revealed that the SBS modified SMA mixes had almost ten times longer fatigue lives than the conventional SMA mixes. Wheel tracking test, which was conducted to evaluate the rutting resistance of mixes, showed that the dynamic stability values of the modified SMA mixes were three times higher than the values of the conventional SMA mixes. In addition, both adhesive tensile strength and low temperature bending strength values of the modified SMA mixes were higher than the values of the conventional SMA mixes by 21∼48% and 22∼38%, respectively. According to the moisture damage tests, the modified SMA mixes satisfied the mix design criteria while the conventional SMA mixes did not stisfy the criteria. Overall, the SBS modified SMA mixes showed better laboratory performance than the conventional SMA mixes.

우리나라 기업의 조세혜택과 내재적 조세에 관한 실증적 연구

이양현,김지범,윤지환 중앙대학교 산업경영연구소 2000 산업경영연구 Vol.9 No.1

본 연구는 Scholes & Wolfson(1992) 의 「Taxes and Business Sstrategy」에서 효율적으로 세무계획을 하려면 투자와 자금조달결정에 있어서 외형적 조세(Explicit Tax)뿐만 아니라 내재적 조세(Implicit Tax)와 같은 간접적인 세금의 효과도 고려해야 한다는데 착안하여 우리 나라 기업소득에 대한 내재적 조세를 이론적으로 분석하고, 실증적으로 검증하였다. 그리고 내재적 조세의 발생에 가장 큰 영향을 미치는 원인변수인 조세혜택에 기업특성변수가 미치는 영향을 분석하였다. 분석결과 조세혜택기업(租稅惠澤企業)과 조세비혜택기업(租稅非惠澤企業) 사이에 부채비율, 수출비율, 자본집약도입비율, 이익증가율 등은 유의적인 차이가 있었지만, 기업규모, 연구개발비율은 유의적인 차이를 보이지 않았다. 또한 기업에 대한 조세혜택의 증가가 세전자기자본수익률의 감소를 가져올 것이라는 내재적 조세가설(內在的 租稅假說)을 실증분석한 결과 표본기간에 걸쳐 표본전체기업을 대상으로 한 분석에서는 독립변수인 세전자기자본조세혜택비율(稅前自己資本租稅惠澤比率)과 종속변수인 세전자기자본수익율(稅前自己資本收益率) 간에는 유의적인 음(-)의 상관관계가 나타나 내재적 조세가 존재하는 것으로 나타났다. Previous horizontal equity studies have measured the variation in explicit taxes only, when both implicit and explicit taxes are considered, apparent horizontal in equity disappear and all that remains is variation due to market imperfection. Researchers have long known of suspected that omitting implicit taxes is a problem in the examining of horizontal equity on the total tax burden. Scholes and Wolfson's(1992) definition of implicit taxes and the advent of experimental markets research provide opportunities to demonstrate the effects of implicit taxes on the measurement of horizontal equity. The concept of implicit tax is based on perfectly competitive market at equilibrium. So the after-tax returns of all investments are equal after adjusting for risk. The empirical test was complied to these two sub samples. tax-advantaged firms and tax-disadvantaged firms. The result of study provides an empirical evidence that there exists a significant inverse relation between pre-tax return and tax subsidy among only tax-disadvantaged firms listed on the korean stock market. Results of previous empirical studies are consistent with the predictions of implicit tax by hypothesis and are statistically significant inverse relation between tax subsidy(PTTSE) and pre-tax return(PTROE), but the empirical relation is weaker than predicted for a pertectly competitive and frictionless market, which is due to presence of market frictions or systematic measurement error. There finding should allow policy makers to enact more effective legislation and enable researchers to construct experiments that have greater power and more internal validity.

심인성 어지럼증 환자의 정신과적 증상에 관한 연구

이경규,이지영,김현우,이정엽,백기청,김재일,이근호 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.5

연구목적 : 어지럼증을 호소하는 환자들 중에 심인성 어지럼증 환자가 상당수 있다는 것은 알려져 있고, 이러한 심인성 어지럼증과 동반되는 정신질환으로는 불안장애, 우울장애, 인격장애 등이 있다. 이에 본 연구에서는 심인성 어지럼증 환자들의 빈도와 정신과적 증상을 알아보고자 하였다. 방 법 : 어지럼증 환자들에게 평형검사, 자세운동측정검사, 자세변화검사, caloric testing을 시행하여 심인성, 말초성 및 중추성의 3군으로 분류한 후 각각 14명, 16명, 32명을 대상으로 하였다. 대상환자들에게 한국판 Beck 우울척도검사(K-BDI), Spielberg의 상태-특성 불안검사(STAI). 간이정신진단검사(SCL-90-R)를 이용하여 정신과적 증상을 측정하여 이들 세 군을 비교분석하였다. 결 과 : 1) 심인성 어지럼증을 가진 환자는 어지럼증을 나타내는 환자 총 62명중에서 14명으로 22.6%를 차지하였다. 2) K-BDI에 따른 세 군간의 비교에서는 세 군간에 유의한 차이를 보이지 않았다. 3) STAI에 따른 세 군간의 비교에서 상태불안(STAI-S) 및 특성불안(STAI-T) 모두에서 세 군간에 유의한 차이를 보이지 않았다. 4) SCL-90-R에 따른 세 군간의 비교에서는 9개의 척도 중에서 공포불안척도에서만 중추성 어지럼증군이 47.56±6.90, 말초성 어지럼증 군이 53.50±13.74, 심인성 어지럼증 군이 58.50±16.05로 심인성 어지럼증 환자군이 중추성 어지럼증 환자군에 비하여 유의하게 높은 것으로 나타났다(p<0.01). 5) 통증 증상에 있어서는 세 군간에 유의한 차이를 보이지 않았고, 위장관 증상과 성기능 장애 증상은 중추성과 말초성 어지럼증 군이 심인성 어지럼증 군에 비하여 유의하게 높은 것으로 나타났다(p<0.01). 결 론 : 상기 결과를 토대로 했을 때 어지럼증 환자들에 대한 정신과적 접근을 위하여 각 군을 나누는 것은 별 의미가 없으며 어지럼증 환자들의 어지럼증 자체에 대한 직접적이고 집중적인 치료가 더욱 필요할 것으로 생각된다. Objectives : This study was aimed to investigate psychiatric symptoms in patients with psychogenic dizziness and compare these findings with those of patients with central and peripheral dizziness. Methods : A total of 62 patients with dizziness was the subject of investigation, and patients were classified into 32 with central type, 16 with peripheral type, and 14 with psychogenic type. Korean standardized Beck Depression Inventory(K-BDI), State and Trait Anxiety Inventory(STAI), and Korean standardized edition of Symptom Checklist 90 Revised(SCL-90-R) were used for the assessment. Statistically, Pearson's chi-square test and one-way ANOVA with Scheffe's test were used with SPSS/PC for windows 6.0. Results : The results were as follows : 1) The proportion of psychogenic dizziness was 22.6% of the total subjects. 2) Total scores of K-BDI were not significantly different among the 3 groups. 3) Total scores of state anxiety and trait anxiety were not significantly different among the 3 groups. 4) In SCL-90-R, psychogenic dizziness group showed significantly higher score of phobic anxiety only(p<0.01) than central dizziness group. And others were not significantly different among the 3 groups. 5) In additional somatic symptoms, pain score was not different among the 3 groups, but gastrointestinal and sexual symptoms scores of central and peripheral dizziness group were significantly higher than those of psychogenic dizziness group(p<0.01). Conclusion : These results suggest that psychiatric symptoms in patients with psychogenic dizziness are not different from those of patients with central or peripheral dizziness. Therefore, the more direct and intensive treatment may be necessary regardless of the type of dizziness.

복귀돌연변이시험을 이용한 이온화에너지 처리 우유 및 아이스크림의 유전독성학적 평가

유지숙, 한선경, 신명수, 구본철, 최지현, 이주운, 조철훈, 함준상, 이완규 충북대학교 동물의학연구소 2008 Journal of Biomedical and Translational Research Vol.9 No.1

본문참고

치근단 미완성 치아의 자가치아이식

정지숙,박호원,이주현,서현우 大韓小兒齒科學會 2012 大韓小兒齒科學會誌 Vol.39 No.1

자가치아이식이란 자신의 치아를 구강 내의 한 위치에서 다른 발치와나 외과적으로 형성된 치조와로 이동시키는 술식이다. 통상적으로 이 술식은 상실되거나 보존하기 힘든 제1대구치를 다른 치아로 대체하거나, 매복된 견치를 악궁의 정상 위치로 이동시키거나, 전치부와 같이 심미적으로 중요한 부위의 상실된 치아를 소구치로 대체하는 경우에 많이 사용된다. 자가치아이식을 성공적으로 수행하기 위해서는 세심한 수술 기법과 더불어 적절한 증례 선택이 중요한데, 이식할 치아는 치근 발육이 1/2~3/4 정도 이루어진 미성숙 치아가 유리하고 근단공이 넓을수록 치수 재혈관화의 가능성도 높아져 이후의 근관 치료의 필요성도 줄일 수 있다. 본 증례들은 소아에서 치근단 미완성 치아의 자가치아이식을 통해 임상적, 방사선학적으로 양호한 치유 결과를 얻었고, 별도의 근관 치료 없이 양호한 치수 치유 결과를 보였기에 보고하는 바이다. Autogenous tooth transplantation can be defined as the surgical movement of a tooth from one position in the mouth to another in the same individual. The most common reasons for tooth transplantation include replacement of a missing first molar, transplantation of impacted canines to their normal positions in the arch, and transplantation of premolars in areas of missing teeth, especially in the anterior area of the mouth. The key to successful tooth transplantation is proper selection of graft with adequate root development as well as the design of surgical operation. Root development stage with half to three-quarter-developed roots increase the success rate of autotransplantation. We report the cases of successful autotransplantation which resulted in ideal healing of periodontal ligament, gingiva and alveolar bone. All transplanted teeth presented immature root formation at the moment of the procedure. After surgical procedure, we can observe good healing pattern without endodontic problem.

정신분열병의 유전적 고위험군에서 인지, 정서 및 사회기능 연구

이경진,위휘,유소영,이애라,송지연,하태현,홍경수,김명선,권준수 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.1

Objectives : Vulnerability marker in biological relatives of schizophrenia may be very useful in identifying the propensity for the development of schizophrenia. This study suggests that the relatives at risk for genetically developing schizophrenia have impairments in several domains of cognition, social function and affective function as a vulnerability marker. Methods : A neurocognitive function test, a social function test and an affective function test were administered to fifteen healthy relatives from families with two or more patients with schizophrenia (geneticallly high risk subjects). Fifteen healthy controls matched for age and gender were recruited in this study. Results : Compared to the control subject, the genetic high risk subjects performed significantly more poorly in the selective attention and recall memory of neurocognitive function. The high dsk subjects also had lower scores in independence-performance and independence-competence of the social function test and emotion control of the affective function test. Conclusion : Selective attention, recall memory, independence-performance, independence-competence and emotion control ability may be a valuable marker for genetic study of schizophrenia.