• 분석과학
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• 제19권1호
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• pp.107-114
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• 2006

본 연구에서는 trimethylsilyl (TMS) 및 trifluoroacetyl (TFA)유도체화를 이용하여 소변여지에서 대사이상 질환을 신속하게 스크리닝하는 GC/MS 분석법을 개발하였다. 유기산과 아미노산을 동시에 유도체화하기 위해 메틸오렌지를 지시약으로 하여 $60^{\circ}C-70^{\circ}C$에서 15-20 분간 카르복실기는 TMS로 아미노기는 TFA로 유도체한 후 GC/MS-SIM으로 분석하였다. 유기산과 아미노산의 직선성의 범위는 0.001-50 mg이었고, 소변에서의 검출한계는 10-200 ng, 정량한계는 80-900 ng 이었다. 직선성을 보이는 범위에서의 상관계수(R2)는 0.994-0.998이었고, 회수율은 methylcitric acid와 glycine을 제외하고 80-100%를 보였다. 이 방법은 기존의 유기산분석에는 GC/MS를 아미노산 분석에는 아미노산분석기를 사용하는 것과 비교할 때 GC/MS만 사용하여 동시에 유기산과 아미노산을 분석함으로써 전처리가 간단하고 짧은 분석시간과 우수한 감도, 정확도, 정밀도를 보여 주었다. 정상인과 대사이상질환 환자의 검체에 적용해 보았을 때, 본 분석방법은 유기산과 아미노산대사이상의 유전성대사질환 환자의 스크리닝, 진단 및 모니터링에 임상적으로 유용함을 보여주었다.

• Journal of Nutrition and Health
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• 제40권8호
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• pp.736-744
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• 2007

과천에서 진행되고 있는 소아 코호트의 1차년도와 2차년도 조사에 모두 참여했던 소아 375명(남아 : 195명, 여아 : 180명)을 연구 대상으로 leptin 수준을 삼분위수로 나누어 leptin 수준에 따른 신체조성 성분 변화를 관찰한 결과에 대한 요약은 다음과 같다. 1) 1차년도 비만 유병률은 남학생이 경도비만 8.7%, 중등도 비만 3.6%였고, 여학생은 경도비만이 1,7%로 관찰되었다. 2) 1, 2차년도의 비만지수(OI), BMI, 허리둘레 수치와 2차년도 leptin, 체지방률, 체지방량 수치들 상호간의 관계를 보았을 때, 남학생의 혈중 leptin 수준과 신체지수와의 관계는 체지방량, 체지방률, BMI 허리둘레, 제지방량의 순으로 양의 상관관계를 보였으며, 특히 leptin의 농도가 높을수록 현재의 체중, 체질량지수, 비만도, 허리둘레, 체지방률이 높았다(p<0.001). 이는 여학생의 경우에도 유사한 상관관계를 나타냈다. 3) leptin과 지방섭취량, 탄수화물 섭취량과의 관계는 유의적인 상관관계를 보이지 않았다. 4) 혈중 leptin 수준을 삼등분하여 그 수준이 최상위 삼분위에 포함되는 어린이 집단의 비만 유병률은 남 34.3%, 여 5% 이었으나 최하위군 에서는 0%이었다. 최상위군의 경우 1년 전의 비만유병률도 유사하였다(남 34.3%, 여 5%). 이상의 결과를 종합해보면 소아의 leptin 수준은 현재의 비만도를 반영할 수 있을 뿐 아니라, 1년 전의 비만상태도 예측이 가능하다. 비만도가 높은 소아의 경우 적극적 개선이 행해지지 않으면 체중 및 비만상태가 1년간 지속되므로 대사증후군 및 심혈관계 질환의 위험이 증가될 것으로 판단되며 이들을 조기에 예측, 관리하는 체계가 필요하다.

• Journal of Nutrition and Health
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• 제24권1호
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• pp.1-11
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• 1991

In this study. the importance of body fat distribution as an indicator of metabolic aberrations in diabetics was'evaluated. Skinfold thicknesses at eight sites and circumferences at five sites and total body fat content were measured on 105 diabetics. 1) The waist/thigh girth ratio(WTR) was positively correlated(r=0.38-0.54) to plasma glucose levels during oral glucose loading in diabetic men alone. 2) There was no significant difference in serum total cholesterol of diabetics and nondiabetics. However, HDL-cholesterol was significantly lower(p : 0.000. in male and female) in diabetics(male : 36.31$\pm$ 16.98mg/dl, female: 37.89$\pm$14.67mg/dl) than nodiabetics(male 61.75$\pm$14.08mg/dl, female : 62.29$\pm$12.65mg/dl) and serum triglyceride was significantly higher(p=0.0212) in diabetic women(171.90$\pm$ 76.61mg/dl) than nondiabetic women(111.10$\pm$42.84mg/dl) . 3) In both sexes. anthropometric measurements that significantly correlated to serum triglyceride concentration were percentage of ideal body weight. body mass index(BMI) and waist circumference. Positive and significant correlations were found between serum cholestrol, and BMI(R: 0.31, 0.34) and waist circumference(r=0.29) in diabetic men. Moreover, skinfolds of trunk area(r=0.29~0.32) especially abdomen, were closely associated with serum lipids than other fat deposits. Increasing percentage of total body fat content was accompanied by progressively increasing serum triglyceride concentration(r=0.41) in dieabetic men. This study shows that knowledge of body fat localization may help identify risks of carbohydrate intolerance and hyperlipidemia in diabetics.

• Archives of Pharmacal Research
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• 제22권5호
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• pp.474-478
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• 1999

Modulation of unscheduled DNA synthesis by dehydroepiandrosterone (DHEA) after exposure to various chemical carcinogens was investigated in the primary rat hepatocytes. Unscheduled DNA synthesis was induced by treatment of such direct acting carcinogens as methly methanesulfonate (MMS) and ethyl methanesulfonate (EMS) or procarcinogens including benzo(a)pyrene (BaP) and 7, 12-dimethylbenz(a)anthracene (DMBA). Unscheduled DNA synthesis was determined by measuring [methyl-3H]thymidine radioactivity incorporated into nuclear DNA of hepatocytes treated with carcinogens in the presence or absence of DHEA. Hydroxyurea $(5{\times}10^{-3} M)$was added to growth medium to selectively suppress normal replication. DHEA at concentrations ranging from $(1{\times}10^{-6} M)$ to$(5{\times}10^{-4} M)$ did not significantly inhibit unscheduled DNA synthesis induced by either MMS $(1{\times}10^{-4} M)$ or EMS $(1{\times}10^{-2} M)$. In contrast, DHEA-significantly inhibited unscheduled DNA synthesis induced by BaP $(6.5{\times}10^{-5} M)$ and DMBA.$(2{\times}10^{-5} M)$. DHEA-induced hepatotoxicity in rats was examined using lactate dehydrogenase (LDH) release as an indicator of cytotoxicity. DHEA exhibit no significant increase in LDH release compared with the control at 18 h. These data suggest that nontoxic concentration of DHEA does not affect the DNA excision repair process, but it probably influence the enzymatic system responsible for the metabolic activation of procarcinogens and thereby decreases the amount of the effective DNA adducts formed by the ultimate reactive carcinogenic species.

• Journal of Animal Science and Technology
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• 제64권6호
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• pp.1013-1023
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• 2022

Body condition score (BCS) at calving is a vital indicator of the effectiveness of the beginning of lactation in dairy animals. The purpose of this study was to examine the effect of BCS at calving on milk production and transition success in dairy buffaloes. Thirty-six (36) Nili Ravi buffaloes were enrolled at 40 days of expected calving and followed through 90 days of lactation. The buffaloes were categorized into three groups according to their BCS (on a scale of 1-5 with 0.25 increments) as follows: 1) low, buffaloes with BCS ≤ 3.0; 2) medium, buffaloes with BCS 3.25-3.5; and 3) high, buffaloes with BCS ≥ 3.75. All buffaloes were fed a similar diet ad libitum. The lactation diet had increased concentrate allowance according to milk yield. The results revealed that the BCS at calving did not affect milk yield; however, fat percentage (fat%) was lower in the low-BCS group. Dry matter intake (DMI) was similar among the treatment groups, although post-calving BCS loss was greater in the high-BCS group compared to the medium- and the low-BCS groups. Similarly, the buffaloes in the high-BCS group had higher non-esterified fatty acids (NEFA) concentration compared to the low- and medium-BCS groups. No cases of metabolic disorders were observed during the study. The present results suggest that the buffaloes in the medium-BCS group appeared to perform better compared to the low- and the high-BCS groups with respect to milk fat% and blood NEFA concentration.

• Asian-Australasian Journal of Animal Sciences
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• 제27권1호
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• pp.69-76
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• 2014

This study was carried out to evaluate the relationship between threonine (Thr) efficiency and Thr dehydrogenase (TDG) activity as an indicator of Thr oxidation on chicks fed with levels of diets (CP [17.5% and 21.5%] and Thr [3.8 and 4.7 g/100 g CP]; glycine [Gly][0.64% and 0.98%] and true digestible Thr [dThr] [0.45% and 0.60%]). Calculation of the Thr efficiency was based on N-balance data and an exponential N-utilization model, and TDG activity was determined as accumulation of aminoacetone and Gly during incubation of hepatic mitochondria. This study found that in the liver of chicks who received a diet containing up to 0.79% Thr (4.7 g Thr/100 g of CP) in the 17.5% CP diet, no significant (p>0.05) effect on TDG activity was observed. However, significantly (p = 0.014) increased TDG activity was observed with a diet containing 21.5% CP (4.7 g Thr/100 g of CP) and the efficiency of Thr utilization showed a significant (p = 0.001) decrease, indicating the end of the Thr limiting range. No significant (p>0.05) effect on the total TDG activity and accumulation of Gly was observed with addition of Gly to a diet containing 0.45% dThr. In addition, addition of Gly to a diet containing 0.60% dThr also did not result in a change in accumulation of Gly. Due to an increase in accumulation of aminoacetone, an elevated effect on total TDG activity was also observed. No significant (p>0.05) reduction in the efficiency of Thr utilization was observed after addition of Gly at the level of 0.45% dThr. However, significantly (p<0.001) reduced efficiency of Thr utilization was observed after addition of Gly at the level of 0.60% dThr. Collectively, we found that TDG was stimulated not only by addition of Thr and protein to the diet, but also by addition of Gly, and efficiency of Thr utilization was favorably affected by addition of Gly at the level near to the optimal Thr concentration. In addition, no metabolic requirement of Gly through the TDG pathway was observed with almost the same accumulation of Gly and a slight increase in TDG activity by addition of Gly. Thus, our findings suggest that determination of TDG activity and parameter of efficiency of Thr utilization may be useful for evaluation of dietary Thr level.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1247-1247
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• 2001

Constituents of animal biofluids such as milk, blood and urine contain information specifically related to metabolic and health status of the ruminant animals. Some changes in composition of biofluids can be attributed to disease response of the animals. Mastitis is a major problem for the global dairy industry and causes substantial economic losses from decreasing milk production and reducing milk quality. The purpose of this study was to investigate potential of NIRS combined with multivariate analysis for cow's mastitis diagnosis based on NIR spectra of milk, blood and urine. A total of 112 bulk milk, urine and blood samples from 4 Holstein cows were analyzed. The milk samples were collected from morning milking. The urine samples were collected before morning milking and stored at -35$^{\circ}C$ until spectral analysis. The blood samples were collected before morning milking using a catheter inserted into the carotid vein. Heparin was added to blood samples to prevent coagulation. All milk samples were analyzed for somatic cell count (SCC). The SCC content in milk was used as indicator of mastitis and as quantitative parameter for respective urine and blood samples collected at same time. NIR spectra of blood and milk samples were obtained by InfraAlyzer 500 spectrophotometer, using a transflectance mode. NIR spectra of urine samples were obtained by NIR System 6500 spectrophotometer, using 1 mm sample thickness. All samples were divided into calibration set and test set. Class variable was assigned for each sample as follow: healthy (class 1) and mastitic (class 2), based on milk SCC content. SIMCA was implemented to create models of the respective classes based on NIR spectra of milk, blood or urine. For the calibration set of samples, SIMCA models (model for samples from healthy cows and model for samples from mastitic cows), correctly classified from 97.33 to 98.67% of milk samples, from 97.33 to 98.61% of urine samples and from 96.00 to 94.67% of blood samples. From samples in the test set, the percent of correctly classified samples varied from 70.27 to 89.19, depending mainly on spectral data pretreatment. The best results for all data sets were obtained when first derivative spectral data pretreatment was used. The incorrect classified samples were 5 from milk samples,5 and 4 from urine and blood samples, respectively. The analysis of changes in the loading of first PC factor for group of samples from healthy cows and group of samples from mastitic cows showed, that separation between classes was indirect and based on influence of mastitis on the milk, blood and urine components. Results from the present investigation showed that the changes that occur when a cow gets mastitis influence her milk, urine and blood spectra in a specific way. SIMCA allowed extraction of available spectral information from the milk, urine and blood spectra connected with mastitis. The obtained results could be used for development of a new method for mastitis detection.

• 대한임상검사과학회지
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• 제49권4호
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• pp.345-349
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• 2017

당뇨병은 대사 증후군 및 심혈관 질환을 비롯한 다양한 건강상의 부작용과 관련이 있다. 또한 당뇨병의 증가로 사회 및 의학적 관심이 증가하고 있다. 제 2 형 당뇨병의 특징 중 하나는 혈당이 증가한다는 것이다. 공복 혈당치는 가장 기본적이고 널리 사용되는 당뇨병의 지표이다. TLR4 발현은 심장에서 비교적 높다. 그러나 공복 시 혈당과 TLR4의 관련성에 대한 연구가 있었다. 한국인에서 TLR4 유전자와 공복 시 혈당의 단일 염기 다형성(SNP)의 관련성을 알아 보았다. 서울시에서 총 994 명을 대상으로 TLR4 SNP를 이용한 연구를 실시했다. 공복 시 혈당과 관련하여 TLR4 유전자 영역은 연쇄 불균형으로 나타 났으며 유전자의 범위가 매우 크기 때문에 여러 개의 LD 블록으로 보였다. TLR4 유전자의 SNP는 평균 공복 시 혈당과 관련이 있었다(p<0.01). 공복 시 혈당과 관련 크기는 p-value를 $-log^{10}$의 값으로 하였다. rs1329067의 minor allele frequency는 16.4%였고 AA 유전자형을 가진 사람들은 GG 유전자형을 가진 사람들 보다 공복 시 혈당이 높았다. 이 연구는 TLR4의 유전 적 변이가 한국 성인의 혈당 수치에 영향을 미친다는 것을 암시한다.

• Journal of Korean Neurosurgical Society
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• 제62권4호
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• pp.476-486
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• 2019

Objective : The functional information of $^{11}C$-methionine positron emission tomography (MET-PET) images can be applied for Gamma knife radiosurgery (GKR) and its image quality may affect defining the tumor. This study conducted the phantom-based evaluation for geometric accuracy and functional characteristic of diagnostic MET-PET image co-registered with stereotactic image in Leksell $GammaPlan^{(R)}$ (LGP) and also investigated clinical application of these images in metastatic brain tumors. Methods : Two types of cylindrical acrylic phantoms fabricated in-house were used for this study : the phantom with an array-shaped axial rod insert and the phantom with different sized tube indicators. The phantoms were mounted on the stereotactic frame and scanned using computed tomography (CT), magnetic resonance imaging (MRI), and PET system. Three-dimensional coordinate values on co-registered MET-PET images were compared with those on stereotactic CT image in LGP. MET uptake values of different sized indicators inside phantom were evaluated. We also evaluated the CT and MRI co-registered stereotactic MET-PET images with MR-enhancing volume and PET-metabolic tumor volume (MTV) in 14 metastatic brain tumors. Results : Imaging distortion of MET-PET was maintained stable at less than approximately 3% on mean value. There was no statistical difference in the geometric accuracy according to co-registered reference stereotactic images. In functional characteristic study for MET-PET image, the indicator on the lateral side of the phantom exhibited higher uptake than that on the medial side. This effect decreased as the size of the object increased. In 14 metastatic tumors, the median matching percentage between MR-enhancing volume and PET-MTV was 36.8% on PET/MR fusion images and 39.9% on PET/CT fusion images. Conclusion : The geometric accuracy of the diagnostic MET-PET co-registered with stereotactic MR in LGP is acceptable on phantom-based study. However, the MET-PET images could the limitations in providing exact stereotactic information in clinical study.

• 생명과학회지
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• 제31권12호
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• pp.1072-1078
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• 2021

구강 병원체 Streptococcus mutans는 인간 충치를 일으키는 주요한 원인균 중 하나로 알려져 있다. 효과적인 구강 건강관리를 위해 치약과 구강 청결제를 포함한 다양한 치과 위생 제품을 사용하고 있지만, 음식 섭취 후 구강 미생물의 재발은 빈번하게 발생한다. 본 연구는 치아우식증의 원인균인 S. mutans를 장시간 배양 시, 관찰된 급격한 세포사가 어느 시점에 유도되는지 분석하고 이러한 생장특성이 특이 대사물질의 분비와 밀접한 관련이 있는지 평가하고자 하였다. 특히, S. mutans의 생균수는 전체 72시간의 배양 중 24시간 이후에 급격히 감소한 반면, 지표균주인 대장균은 동일한 시간에 일정한 수준의 생균수를 유지하였다. 다음으로 S. mutans 배양액에 동종의 세포사를 유도하는 특정 신호물질이 포함되어 있는지를 확인하기 위해 균주의 배양 24시간 후에 배양액을 회수하였다. 비록 세포의 성장이 완전히 복구되지 않았지만, 배양액의 산성 pH를 중화하고 포도당을 보충한 조건에서 복구된 표현형이 일부 관찰되었다. 그러나 배양액의 낮은 pH의 중화만으로는 세포 생장이 전혀 회복되지 않았다. 이러한 S. mutans의 세포사는 영양소 고갈뿐만 아니라 신호전달과 밀접하게 연관될 수 있으므로 이러한 생존 표현형에 대한 이해는 S. mutans의 생물학에서 세포 간 신호전달체계에 대한 새로운 지식을 제공할 수 있다.