Original Article : Evaluation of Renal Toxicity by Combination Exposure to Melamine and Cyanuric Acid in Male Sprague-Dawley Rats

( Ji Yeon Son ),( Yoon Jong Kang ),( Kyeong Seok Kim ),( Tae Hyung Kim ),( Sung Kwang Lim ),( Hyun Jung Lim ),( Tae Cheon Jeong ),( Dal Woong Choi ),( Kyu Hyuck Chung ),( Byung Mu Lee ),( Hyung Sik Ki 영남대학교 약품개발연구소 2014 영남대학교 약품개발연구소 연구업적집 Vol.24 No.0

Melamine-induced nephrotoxicity is closely associated with crystal formation in the kidney caused by combined exposure to melamine (Mel) and cyanuric acid (CA). However, there are few dosage-finding studies for toxicological evaluation of chronic co-exposure to Mel and CA. The objective of this study was to investigate the possible mechanism by which a Mel and CA mixture lead to renal toxicity in rats. Mel and CA were co-administered to rats via oral gavage for 50 days. Nephrotoxicity was determined by measuring blood urea nitrogen (BUN) and serum creatinine (sCr) levels. Relative kidney weights were significantly increased in rats after co-exposure to Mel+CA (63/6.3 or 630/6.3 mg/kg) mixtures. BUN and sCr levels were significantly increased after Mel and CA co-exposure. Taken together, significant increase in KIM-1, NGAL, and calbindin levels were observed in the urine of rats exposed to Mel+CA (63/6.3 or 630/6.3 mg/kg) compared with the corresponding control group. Histological analysis revealed epithelial degeneration and necrotic cell death in the proximal tubules of the kidney after co-exposure to Mel+CA (63/6.3 or 630/6.3 mg/kg). Our data suggest that Mel-mediated renal toxicity may be influenced by CA concentrations in Mel-contaminated milk or foods.

Evaluation of Renal Toxicity by Combination Exposure to Melamine and Cyanuric Acid in Male Sprague-Dawley Rats

Ji Yeon Son,Yoon Jong Kang,Kyeong Seok Kim,Tae Hyung Kim,Sung Kwang Lim,Hyun Jung Lim,Tae Cheon Jeong,Dal Woong Choi,Kyu Hyuck Chung,Byung Mu Lee,Hyung Sik Kim 한국독성학회 2014 Toxicological Research Vol.30 No.2

Melamine-induced nephrotoxicity is closely associated with crystal formation in the kidney caused by combined exposure to melamine (Mel) and cyanuric acid (CA). However, there are few dosage-finding studies for toxicological evaluation of chronic co-exposure to Mel and CA. The objective of this study was to investigate the possible mechanism by which a Mel and CA mixture lead to renal toxicity in rats. Mel and CA were co-administered to rats via oral gavage for 50 days. Nephrotoxicity was determined by measuring blood urea nitrogen (BUN) and serum creatinine (sCr) levels. Relative kidney weights were significantly increased in rats after co-exposure to Mel+CA (63/6.3 or 630/6.3 mg/kg) mixtures. BUN and sCr levels were significantly increased after Mel and CA co-exposure. Taken together, significant increase in KIM-1, NGAL, and calbindin levels were observed in the urine of rats exposed to Mel+CA (63/6.3 or 630/6.3 mg/kg) compared with the corresponding control group. Histological analysis revealed epithelial degeneration and necrotic cell death in the proximal tubules of the kidney after co-exposure to Mel+CA (63/6.3 or 630/6.3 mg/kg). Our data suggest that Mel-mediated renal toxicity may be influenced by CA concentrations in Mel-contaminated milk or foods.

치과 기공사들에게서 나타나는 호흡기 증상과 이의 관련 요인

김웅철,오세윤,김지환,김진완,이준석,이가영,이세훈,유진호,김태석 高麗大學校 倂設 保健大學 保健科學硏究所 2001 保健科學論集 Vol.27 No.1

This study was carried out to investigate subjective respiratory symptoms and their attributable factors in Korean dental laboratory technicians. A questionnaire was mailed to randomly selected 1,900 dental laboratory technicians. Among them, 1,344 dental technicians completed the questionnaires and returmned them. Validity and reliability tests on the questionnaires were carried out before the main survey. To investigate risk factors on respiratory subjective symptoms, we performed analysis on distribution of characteristics, and then investigated univariate analysis and multiple logistic regression analysis. The prevalence rate of wheezing, cough and phlegm, and dyspnea was 4.8%, 33.9%, 54.9%, respectively. Statistically significant factors inducing subjective respiratory symptoms by multiple logistic regression analysis were sex, smoking, exercise, health examination, work hours a day, investment gas, investment dust, metal fume, resin vapor, and asbestos dust. Considering the results above, it seems that most subjective respiratory symptoms are related with health habits and occupational environmental-related factors. The result, consideration in mind, suggest that health promotion programs for smoking cessation, regular health examination, and physical exercise in health habit, and improvement on casting and resin work in dental technological environment be necessary.

Evaluation of Renal Toxicity by Combination Exposure to Melamine and Cyanuric Acid in Male Sprague-Dawley Rats

Son, Ji Yeon,Kang, Yoon Jong,Kim, Kyeong Seok,Kim, Tae Hyung,Lim, Sung Kwang,Lim, Hyun Jung,Jeong, Tae Cheon,Choi, Dal Woong,Chung, Kyu Hyuck,Lee, Byung Mu,Kim, Hyung Sik Korean Society of ToxicologyKorea Environmental Mu 2014 Toxicological Research Vol.30 No.2

Melamine-induced nephrotoxicity is closely associated with crystal formation in the kidney caused by combined exposure to melamine (Mel) and cyanuric acid (CA). However, there are few dosage-finding studies for toxicological evaluation of chronic co-exposure to Mel and CA. The objective of this study was to investigate the possible mechanism by which a Mel and CA mixture lead to renal toxicity in rats. Mel and CA were co-administered to rats via oral gavage for 50 days. Nephrotoxicity was determined by measuring blood urea nitrogen (BUN) and serum creatinine (sCr) levels. Relative kidney weights were significantly increased in rats after co-exposure to Mel+CA (63/6.3 or 630/6.3 mg/kg) mixtures. BUN and sCr levels were significantly increased after Mel and CA co-exposure. Taken together, significant increase in KIM-1, NGAL, and calbindin levels were observed in the urine of rats exposed to Mel+CA (63/6.3 or 630/6.3 mg/kg) compared with the corresponding control group. Histological analysis revealed epithelial degeneration and necrotic cell death in the proximal tubules of the kidney after co-exposure to Mel+CA (63/6.3 or 630/6.3 mg/kg). Our data suggest that Mel-mediated renal toxicity may be influenced by CA concentrations in Mel-contaminated milk or foods.

Gray 사상을 이용한 이진 낮은 상관구역 수열군의 생성법

장지웅(Ji-Woong Jang),김영식(Young-Sik Kim),임대운(Dae-Woon Lim) 한국통신학회 2009 韓國通信學會論文誌 Vol.34 No.2C

본 논문에서는 이진 낮은 상관 구역 수열군의 새로운 생성법을 제안한다. 새로운 수열군은 Kim과 Jang, No, Chung이 제안한 4진 낮은 상관 구역 수열군에 Gray 사상을 적용하여 생성한다. 새로 생성된 이진 수열군의 주기는 생성에 사용한 4진 수열군의 주기의 2배이며, 낮은 상관구역 내 상관 값의 최대 크기 및 수열군의 크기는 생성에 사용한 수열군의 그것의 2배가 된다. 그러나 낮은 상관 구역의 크기는 그대로 유지된다. 생성에 사용한 4진 낮은 상관 구역 수열군의 최적인 경우 새로 생성된 이진 수열군은 높은 확률로 최적의 수열군이 된다. In this paper, we propose a new construction method of binary low correlation zone (LCZ) sequence set. New construction method applies Gray mapping to conventional quaternary LCZ sequence set that has specific property. The period of new binary sequence set is twice as that of used sequence set in construction, and maximum magnitude of correlation value within the LCZ and cardinality of new set is also twice as those of used quaternary sequence set. But the LCZ size is the same with that of used sequence set. If the used quaternary sequence set is optimal, the constructed binary sequence set is optimal with high probability.

악안면 골격 형태에 따른 교합평면각의 변화에 관한 두부 방사선학적 연구

오세윤,김웅철,김지환,이준석,김진완,유진호,김태석 高麗大學校 倂設 保健大學 保健科學硏究所 1999 保健科學論集 Vol.25 No.1

A correlation analysis was made to understand the interaction between the growth patterns of some craniofacial skeletal components and occlusal plane inclination. 5 angular measurements(S.a. Ar.a, Go.a, UGo.a, LGo.a), 6 linear measurements(ACBL, PCBL, RH. MBL. AFH. PFH) and OP/SN. obtained from 83 cephalometric tracing records, were selected and the relationship between the occlusal plane angle and those measurements were analyzed statistically. Ramus Height(r=-0.55), Posterior Facial Height(r=-0.41), were found to be negatively related with Occlusal Plane angle, while Lower Gonial angle(r= 0.35), Saddle angle(r= 0.24) were found to be positively related with Occlusal Plane angle(p(0.05). The results obtained from the above analysis were further assessed with stepwise regression analysis, using Occlusal Plane angle as a dependant variable, and RH, LGo.a and S.a as explanatory variables. Stepwise regression analysis revealed that all the explanatory variables were found to be significant.(p<0.05) [OP/SN] = -8.74-0.33(RH)+0.23(S.a)+0.20(LGo.a). (R²=0.44). This stepwise regression analysis explains, to some extent, the relationship between the growth patterns of some craniofacial skeletal components and the occlusal plane inclination. 1. The inclination of Occlusal Plane angle is noticeably related with the growth patterns of some craniofacial skeletal components, i.e. RH, PFH, Saddle angle and Lower Gonial angle 2. In high Occlusal Plane angle, the Ram us Height tends to be shorter, and the Saddle angle and Lower Gonial angle tend to be obtuse.

정신분열증 환자에서 주관적 음성증상경험의 임상적 의의

김지웅,김찬형,구민성,손석한,박진철,최문종,이은철,윤도준,이홍식 대한신경정신의학회 1999 신경정신의학 Vol.38 No.1

연구목적 : 현재까지 정신분열증의 음성증상평가는 주로 객관적인 평가에만 의존해왔기 때문에, 환자들이 주관적으로 직접 경험하는 음성증상의 평가는 경시된 경향이 있었다. 그러나 실제 많은 정신분열증 환자들은 음성증상을 자가하고 있다. 특히, 개관적인 양성 및 음성증상이 관찰되지 않는 경우에도 환자 본인은 음성증상으로 괴로워한다는 이전의 연구보고들이 있었다. 따라서 저자들은 주관적인 음성증상경험과 개관적인 양성증상 및 음성 증상, 우울증상, 불안증상, 추세외로증상과의 상관성을 알아봄으로써 정신분열증의 정신병리에 있어 주관적 음성증상의 존재를 규명하고, 정신분열증 정신병리의 발생기전을 유추해보며 이차적 음성증상과의 관계를 규명하고자 하였으며. 이러한 연구가 정신분열증 정신병리를 이해하는데 도움을 줄 수 있을 뿐 아니라 환자를 공감적으로 이해하는데 도움을 줄 수 있을 것으로 생각되어 본 연구를 시행하였다. 방 법 : DSM-Ⅳ 진단기준의 정신분열증 진단기준에 해당하는 환자를 대상으로 하였다. 주관적인 음성증상의 평가를 위해서 Scale for the Subjective Experience of Negative Symptoms : Korean version(KSENS)을 이용하였고, 개관적인 정신분열증 정신병리의 평가는 Positive and Negative Syndrome Scale(PNASS)를 이용하였다. 우울증상, 불안증상, 추세외로증상의 평가를 위해서 각각 Hamilton Rating Scale for Depression(HAM-D), Hamilton Rating Scale for Anxiety(HAM-A), Extrapyramidal Symptoms Rating Scale(ESRS)을 이용하였다. 각 정신병리척도 점수간의 상관성은 Spearman 상관계수를 이용하여 분석하였다. 결 과 : K-SENS 24항목 중에서 환자가 이를 불편한 것으로 경험하고 있는 항목의 비율과 PANSS 양성척도점수 사이에는 유의한 상관점이 있었으며 (r=-0.40, p〈0.05), 양성증상 중에서도 특히 과대성(r=-0.46, p〈0.05), 의심/피해(r=-0.34, p〈0.05), 적개심(r=-0.52, p〈0.05) 등의 증상과 유의한 상관관계를 보였다. K-SENS 24 항목 중에서 환자가 이를 불편한 것으로 경험하고 있는 항목의 비율과 PANSS 전체점수(r=-0.25, p〉0.05), PANSS 음성척도점수(r=-0.20, p〉0.05), PANSS 일반정신병리척도(r=-0.08, p〉0.05),와는 각각 유의한 상관성이 없었다. K-SENS 24항목 중에서 환자가 이를 불편한 것으로 경험하고 있는 항목의 비율과 HAM-D 점수(r=-0.01, p〉0.05), HAM-A 점수(r=-0.11, p〉0.05), ESRS 총점(r=0.34, p〉0.05)은 각각 유의한 상관성이 없었다. 결 론 : 본 연구결과에서, 정신분열증 환자들이 불편한 것으로 경험하는 주관적 음성증상과 과대성, 의심/피해, 적개심 같은 양성증상은 역상관관계가 있었으며, 이러한 결과를 바탕으로 양성증상이 주관적으로 불편하게 느끼는 음성증상에 대한 가능성과, 혹은 양성증상이 심할 경우, 이에 압도되어 음성증상을 주관적으로 느끼지 못할 수 있다는 가능성이 시사되었으며, 향후 종적인 연구를 통해 이를 규명해 볼 필요성이 제시되었다. 주관적인 음성증상경험과 우울증상, 불안증상, 추세외로 증상과는 상관성이 없는 것으로 나타나서 이들 증상과는 독립적인 증상임을 시사한다. Objective : Since the evaluation of negative symptoms has depended on the clinician's objective observation, the patients subjective experience of negative symptoms has been neglected. However, in fact, a lot of patients are aware of their negative symptoms. There are several reported suggesting that patients suffer from the subjective experiences of their deficit symptoms, even though the objective positive and negative symptoms cannot be observed. Under these circumstances, we have attempted this study with the idea that it would be helpful in understanding the psychopathology of schizophrenia. Also it would help clarifying the relationship between subjective experience of negative symptoms and objectives positive and negative symptoms, depression anxiety symptoms, and extrapyramidal symptoms. Method : All the 37 patients satisfied the diagnostic criteria of DSM-Ⅵ for schizophrenia. The subjective experiences of negative symptoms were evaluated using Scale for the Subjective Experience of Negative Symptoms : Korean version(KSENS), and for the depression, anxiety, extrapyramidal symptoms, we used Hamilton Rating Scale for Depression(HAM-D), Hamilton Rating Scale for Anxiety(HAM-A), and Extrapyramidal Symptoms Rating Scale(ESRS). The correlation between each psychopathology was tested by calculating Spearman correlation coefficient. Results : There was a significant correlation between the ratio of items experienced as uncomfortable symptoms among 24 items of K-SENS, and the score of PANSS positive subscale(γ=-0.40, p〈0.05), Among the positive symptoms, grandiosity(γ=-0.46, p〈0.05), suspiciousnes/persecution(γ=-0.34, p〈0.05), and hostility(γ=-0.52, p〈0.05) showed a significant correlation with the ratio of items experienced as uncomfortable symptoms among 24 items of K-SENS. There was no significant correlation between the ratio of items experienced as uncomfortable symptoms among 24 items of K-SENS, and PANSS total score(γ=-0.25, p〉0.05), or negative subscale score(γ=-0.20, p〉0.05), or general psychology subscale score(γ=-0.08, p〉0.05), respectively. There was no significant correlation between ratio of items experienced as uncomfortable symptoms among 24 items of K-SENS, and HAM-D(γ=-0.01, p〉0.05), or HAM-A(γ=-0.11, p〉0.05), ESRS(γ=0.34, p〉0.05), respectively. Conclusion : These revealed that the negative correlation between the subjective negative symptoms experienced as an uncomfortable ones and the objective symptoms such as grandiosity, suspiciousness/persecution, and hostility. From these results, the possibility that positive symptoms are used as a defense to hide from the negative symptoms because they are overwhelmed by their positive symptoms, is suggested. These results also suggest that subjective experiences of negative symptoms are independent from depression, anxiety and extrapyramidal symptoms.

農業技術 弘報用 印刷媒體의 製作活用改善에 관한 硏究

金性洙,崔敏浩,鄭址雄,權一男 서울大學校 農科大學 1986 서울대농학연구지 Vol.11 No.1

The objectives of the study were to: 1) analyze the structure and styles of the printed media for agricultural information, 2) review the utilization of the magazine by farmers and extension workers, 3) survey the needs of subscribers for the printed media, 4) find ways for improvement in putting out the magazine, and 5) recommend effective methods for publication and utilization of the printed media. Data were collected by mail and group interview from 179 of the randomly sampled farmers and from 148 of the extension agents in selected areas in Korea. The data were analyzed by HP 3000 computer in the College of Agriculture, Seoul National University. Major statistical techniques used for the study were frequency distrbution, percentile. The results of the study were as follows: 1. Communication exposure of the farmers to the printed media was lower than that of the extension agents, however the level of exposure was considerably high considering limited number of copy for farmers. 2. Farmers' major channel for acquisition of new farming technology was personal communication with extension agents, and extension agents' major channel for advanced technology was printed media. 3. It was revealed that the farmers did not have any difficulty in understanding contents of the printed media. 4. The printed media had been providing long range information for the farmers and extension agents. The farmers and extension agents responded that the consistency in the table of contents and the articles was good, and they liked the idea of emphasis by adopting the box style editing. 5. The farmers responded that the topics of the magazine should reflect the current change in agriculture. 8. The farmers responded that they would like to see articles on horticulture and successful case stories in farming. 9. The farmer-subscriber fully utilized information on farming and rural life in the printed media. Extended distrubution of the printed media would be necessary to enlarge the benefit from the advanced farming technology and improved rural home life.

치과기공사 국가시험 과목 타당성 연구

김웅철,이원철,손영석,오세윤,김부섭,유진호,김지환 한국보건의료인국가시험원 2005 보건의료교육평가 Vol.2 No.1

This study prepared a basic framework for the development and improvement of Korean Dental Technicians' Licensing Examination, based on actual test questions. A peer review was conducted to ensure relevance to current practices in dental technology. For the statistical analysis, 1000 dental laboratory technicians were selected; specialists in dental laboratory technology (laboratory owners, educators, etc.) were involved in creating valid and reliable questions. Results indicated that examination subjects should be divided into three categories: basic dental laboratory theory, dental laboratory specialties, and a practical examination. To ensure relevance to current practice, there should be less emphasis on basic dental laboratory theory, including health-related laws, and more emphasis on dental laboratory specialties. Introduction to dental anatomy should be separated from oral anatomy and tooth morphology; and fixed prosthodontics should be separated from crown and bridge technology and dental ceramics technology. Removable orthodontic appliance technology should be renamed 'orthodontic laboratory technology'. There should be less questions related to health related law, oral anatomy, dental hygiene, dental materials science and inlay, while the distribution ratio of questions related to tooth morphology should be maintained. There should be a decrease in the distribution ratio of questions related to crown and bridge technology, dental ceramics technology, complete dentures and removable partial dentures technology, and orthodontic laboratory technology. In the practical examination, the current multiple choice test should be replaced with tooth carving using wax or plaster. In dental laboratory specialties, subjects related to contemporary dental laboratory technology should be included in the test items.

Tilt&Turn 개폐방식 창호의 재질별 단열성능에 관한 실험적 연구

김수진,노지웅 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

This research wishes to utilize to pabulum distinguish thermal insulation ability that become different according to material of windows and doors and opening type and grasp heat transfer phenomenon that happen on windows and doors interior hereafter because using the distinguished data.