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.

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.

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.

상악 4절치의 후방견인시 나타나는 현상에 관한 유한요소법적 분석

천옥진,김태우,서정훈 대한치과교정학회 1995 대한치과교정학회지 Vol.25 No.5

상악치열에서 제 1 소구치를 발거하고, 이 위치로 견치를 후방이동시킨 상태에서 retraction archwire를 사용하여 상악 4절치를 한 묶음으로 후방견인시켰을 때 초기에 나타나는 모든 힘 체계와 개개치아의 이동양상을 살펴보고 바람직하지 않은 치아이동을 감소시키기 위한 방안을 모색하고자 본 연구를 시행하였다. 먼저 유한요소법을 이용하여 상악 치아와 치근막의 해부학적 형태 및 생체적 특성을 컴퓨터로 재현시키고 모형화된 브라켓을 부착시킨 후, beam 요소를 사용하여 5종의 retraction loop를 하나씩 부여한 다섯 가지의 탄선을 모형화하고, 브라켓과 탄선간에는 gap 요소를 사용하여 모형화함으로써 전체 유한요소 모형을 완성하였다. loop의 형태, activation의 양, gable bend와 torque의 조건에 따른 차이를 검토하기 위해, 각 조건을 변화시켜 loop를 activation시켰을 때 탄선이 발휘하는 힘과 모멘트, 치아이동의 변위를 3차원적으로 정량적 및 가시적으로 평가하고 비교, 분석한 결과 다음과 같은 결론을 얻었다. 1. tear-drop loop archwire 사용시 각 치아의 근원심이동 및 설측이동이 발치공간 폐쇄에 도움이 되었으나, 바람직하지 못한 상하이동과 각 방향으로의 회전이동이 부가적으로 나타났다. 2. 다섯 가지의 retraction archwire 중 T-loop archwire에서 공간폐쇄에 도움이 되는 치아이동이 가장 작게 나타났으며, 각 방향으로의 회전이동 역시 가장 작게 나타났다. 3. tear-drop loop archwire에서 activation 양을 증가시킴에 따라 공간폐쇄에 도움이 되는 치아이동이 점차 증가했으나, 바람직하지 못한 상하이동과 각 방향으로의 회전이동이 함께 증가했다. 4. tear-drop loop archwire에서 loop의 전후방에 gable bend 부여시 전치에서 근원심방향의 치체이동에 도움이 되었으나, 모든 치아에서 상하이동과 각 방향으로의 회전이동이 함께 증가했다. 5. tear-drop loop archwire의 절치부에 치근 설측 torgue 부여시 이들 치아의 순설경사를 개선시키는 효과를 얻었으나, 그 반작용으로 견치 치관의 설측회전이 크게 증가했으며, 전치의 상하이동과 모든 치아에서 각 방향으로의 회전이동이 증가했다. This study was designed to investigate force systems and tooth movements produced by retraction archwire during retraction of four maxillary incisors after the maxillary canine retraction into the maxillary first premolar extraction space using the computer-aided three-dimensional finite element method. A three-dimensional finite element model, consisting of 2248 elements and 3194 nodes, was constructed. The model consisted of maxillary teeth and surrounding periodontal membranes, .022˝x.028˝-slot brackets, and 5 type of retraction archwires(.019˝x.025˝stainless steel archwire) modeled using the beam elements. The contact between the wire and the bracket slot was modeled using the gap elements because of the non-linear elastic behaviors of the contact between them. The forces and moments, and displacements produced by retraction archwire were measured at various conditions to investigate the difference according to types of loops, magnitudes of activation force, gable angle, and anterior lingual root torque. The results were expressed quantitative and visual in the three-dimensional method. The following conclusions can be drawn form this study : 1. When the tear-drop loop archwire was activated, the mesio-distal and lingual translational movements of the teeth helped to close the extraction space, but unwanted movements of the teeth including intrusions and extrusions, and rotational movements in each direction occurred. 2. Activation of T-loop archwire compared with those of other types of retraction archwires produced the least translational movements of the teeth helped to space closure and also least unwanted movements of the teeth. 3. Increasing amount of activation in the tear-drop archwire led not only to increase of translational movements of the teeth helped to space closure, but also increase if unwanted movements of the teeth. 4. Addition of gable bend in the tear-drop archwire helped anterior teeth to translational movements in the mesio-distal direction, but increased unwanted movements of the teeth. 5. Addition of anterior lingual torque in the tear-drop archwire helped central and lateral incisor to improve their facio-lingual inclination, but increased unwanted movements of the teeth.

최대운동부하후 회복기중의 심박수·산소섭취량 변화와 유산소성 운동능력과의 관계 분석

김기진,박현,전태원 師範大學 體育硏究所 1988 서울大學校 體育硏究所論集 Vol.9 No.1

For the evaluation of cardiovascular function, aerobic capacity with VO₂max and AT(anaerobic threshold)have been used as a critical parameter. Also we expect that parameter during recovery can be used as a good one. The purpose of this study was to identify the relationship between maximal or submaximal aerobic capacity and the recovery rate of them. We studied with twenty seven subjects: 7 judoists, 10 long distance runners and 10 non-athletes. They were undergone a continuous incremented treadmill test from rest to all-out. Respiratory gas of each subjects was analyzed by using an automated respiratory gas analyzer, Ergo-Oxyscreen System (Erich-Jaeger Co.). As the data of heart rate, oxygen uptake at rest and during recovery made the log linear model with time, the gradient of recovery rate was calculated by the equation of simple regression with the time as independent variable. That equation is as follows; y=A+B.e?? ? y:HR or VO₂ ? A:expected value at rest ? B:maximum increment ? c:recovery rate The results of this study was; 1. There was a significant difference as the order of long distance runners, judoists, non-athletes' HR at rest, but there was no difference in the maximal HR. 2. Long distance runners had higher level of VO₂max(84.83ml/kg) and AT(80.03%) than the other two groups. 3. In the long distance runners group, the phase of VO₂recovery showed significant correlation with the other factors. 4. In judoists group, the phase of VO₂max recovery had significant correlation -0.79(p<0.05) with the maximal HR. 5. In all subjects, significant correlation was showed between AT, HR at rest and recovery of VO₂. In brief, maximal or submaximal aerobic capacity(VO₂max, AT etc.) had no correlation with the phase of HR recovery, but significant correlation with the phase of VO₂recovery in athletes. The results indicated that the recovery rate of oxygen uptake could be a critical index for evaluating the aerobic capacity.

LRFD 설계법에 의한 강박스거더 합성형교 설계 프로그램

김천용,권태형,이창열,신동구 明知大學校 産業技術硏究所 2006 産業技術硏究所論文集 Vol.25 No.-

A C++ based computer program for the design of composite steel-concrete box girder by the LRFD method is developed. The program consists of a main program, a header program, and 16 function programs. The load analysis for live and dead loads is performed by using the influence line based on the 3-moment method. For the design of box girder, strength limit states, fatigue limit state, and service limit state are considered. In addition, the constructibility of the girder is also checked. The validity of the program is demonstrated by comparing the design result for 3-span continuous box girder by the present program with the one by hand-calculation.

우리나라 상차림의 영양적 평가

김영순,이정희,오순덕,김수현,이정민,남택수,박태식,천유정 高麗大學校 倂設 保健大學 保健科學硏究所 2002 保健科學論集 Vol.28 No.1

This study was carried out to investigate the current nutritional problems owing to the increased consumption of westernized food in Korea and also was conducted to compare the nutritional characteristics of Korean traditional meal with those of the Western diet in similar serving size. The results obtained from nutritional evaluation are as follows: 1. The percentage of calories represented by carbohydrate: lipid: protein was 65:15:20 respectively for Korean traditional meal (Table setting of 3 Chop) therefore these ratios meet the dietary recommended allowances for Koreans. 2. Nutrient values of Korean traditional 3-Chop were shown to be better balanced than those of Western diet when the nutrients of the two types of diet were estimated by similar serving sizes and calories. 3. Compared to the Korean traditional meal, most fast foods were nutritionally imbalanced especially in that most of them showed higher amounts of fats. These results show that Korean traditional meals supply ideal nutrient intakes in contrasts to the westernized diet, therefore much work remains in developing a variety of menus and standard recipes for Korean traditional meals according to the changes in diet trends as well as emphasing the importance of Korean traditional meals as part of an ideal, well-banlanced diet.

Bacillus brevis CD162 Cyclodextrin Glycosyltransferase의 정제 및 특성

김명희,손천배,임영희,오태광 대전대학교 이과대학 기초과학연구소 1997 自然科學 Vol.- No.-

Bacillus brevis CD162가 생산하는 cyclodextrin glycosyltransferase (CGTase)를 ammonium sulfate 침전, DEAE-Sephadex CL-6B 및 Sephadex G-150 컬럼 크로마토그래피를 수행하여 분리정제하였다. 정제된 CGTase는 분자량이 약74.000, 등전점은 약 6.3인 단백질이었고, 정제된 단백질을 SDS-PAGE한 후 변성된 단백질을 재활성시켜 zymogram을 수행한 결과 cyclodextrin glycosyltransferase임을 확인할 수 있었다. 이 효소의 최적활성 pH와 온도는 각각 8.0과 55℃이었으며, pH 5.5~9.0과 50℃까지 안정한 활성을 보였다. 또한, CGTase의 NH₂-말단 부위의 아미노산서열은 Ser-Val-Thr-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln 이었으며, 전분으로부터 cyclodextrin으로의 전환률을 분석한 결과, α-cyclodextrin은 1.3%, β-cyclodextrin은 33.9%, γ-cyclodextrin은 9.7% 이었다(1997년 7월 10일 접수, 1997년 9월 25일 수리) The cyclodextrin glycosyltrasferase (CGTase, EC 3.2.1.19) from Bacillus brevis CD162 was purified by precipitating with ammonium sulfate, DEAE-Sepharose CL-6B column chromatography and Sephadex G-150 column chromatography. The molecular mass and pI of the purified enzyme were estimated to be 74,000 and 6.3 by SDS-PAGe and isoelectric focusing, respectively. The purified enzyme was clearly identified as the CGTase by zymogram after SDS-PAGE. The optimum pH and temperature for the enzyme activity were 8.0 and 55℃, respectively. The enzyme was stable at the range of pH 5.5~9.0, and up to 50℃. The amino acid sequence from the NH₂-terminal of the purified CGTase was Ser-Val-Thr-Asn-Lys-Val-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln. The yields of the products from starch as the substrate were 1.3% for α-,33.9% for β-, and 9.7% for γ-cyclodextrin.

Γ-Cyclodextrin Glycosyltransferase 생산균주의 분리, 동정 및 효소 생산조건

김명희,손천배,임영희,배경숙,오태광 대전대학교 이과대학 기초과학연구소 1997 自然科學 Vol.- No.-

Cyclodextrin glycosyltransferase 생산균주를 토양으로부터 분리하여 형태학적, 생화학적 그리고 균주의 세포벽 지방산 조성분석에 의해 Bacillus brevis로 동정하였고, Bacillus brevis CD162로 명명하였다. 또한 배지조성에 따른 cyclodextrin glycosyltransferase의 최적생산조건을 검토한 결과, 2.0% soluble starch, 0.75% yeast extract, 0.5% bacto peptone, 0.2% KHPO₄, 0.05% MgSO₄·7H₂O, 1.5% Na₂CO₃ (pH 10.2)의 배지 조건에서 30℃에서 96시간 배양하였을 때 가장 높은 효소생산인 0.9 unit/ml을 얻을 수 있었다.(1997년 7월 10일 접수, 1997년 11월 21일 수리) A cyclodextrin glycosyltransferase-producing bacterium was newly isolated from soil using alkaline pH medium containg 1% Na₂CO₃, The isolated strain was identified as Bacillus brevis by morphological and biochemical characteristics, and designated Bacillus brevis CD162. The strain showed the best enzyme production of 0.9 unit/ml after 96 hrs of culture at 30℃ in a medium of 2.0% soluble starch, 0.75% yeast extract, 0.5% bacto peptone, 0.2% K₂HPO₄, 0.005% MgSO₄·7H₂O and 1.5% Na₂Co₃at initial pH 10.2

총수담관결찰이 백서 신세뇨관의 S-100 면역반응에 미치는 영향

金天浩,李永浩,朴景蘭,申台均,金源式 충남대학교 의과대학 지역사회의학연구소 1991 충남의대잡지 Vol.18 No.1

For the study on the changes of S-100 reactivity at the renal tubular epithelium of rats(SpragueDawley, b.w. 250± 20gm. male), the common bile duct ligation was performed under ether anesthesia. At 1st, 3rd, 5th and 7th day after operation, the S-100 immunoreactivity were compared with control rats. The results were as followings; 1. In the control rat, S-100 positive reactions were observed at the collectiong tubule, Henle's loop, distal tubule(partly) and renal papilla. 2. In common bile duct ligated rats, S-100 positive reactions were observed at the proximal convoluted tubule in the rats 1 day after operation, and at the collecting tubule and proximal convoluted tubule in the 3 days after operation.