• 한국식품위생안전성학회지
• /
• 제22권4호
• /
• pp.243-247
• /
• 2007

헤드스페이스-기체크로마토그래프/질량분석기를 이용하여 음료류 중 벤젠을 분석하였다. 대상식품은 시중에 유통되는 과실쥬스 2종, 과실음료 6종, 착향탄산음료 11종, 혼합음료 55종, 추출음료 7종, 음료베이스 4종 등 총 85종이었다. 헤드스페이스의 상평형을 위하여 $40^{\circ}C$에서 30분간 교반하였으며 오븐온도는 초기 온도 $60^{\circ}C$에서 5분간 유지 후 $15^{\circ}C$/분의 비율로 $180^{\circ}C$까지 상승하였다. 내부표준물질로는 벤젠-d6을 사용하였다. 선택이온 m/z 51, 77, 78로 확인하였으며 선택이온 m/z 78에 대한 m/z 77의 반응세기비로 재검증하였다. 벤젠의 선택이온 m/z 78과 내부표준물질 벤젠-d6의 선택이온 m/z 84에 대한 피크 면적비로 정량하였다. 회수율은 $91{\sim}101%$이었으며, 정량한계는 $1{\mu}g/kg$이었다. 벤젠의 평균검출수준은 과실음료의 경우 $5{\mu}g/kg$, 착향탄산음료의 경우 $2{\mu}g/kg$, 혼합음료의 경우 $7{\mu}g/kg$, 추출음료의 경우 $7{\mu}g/kg$이었다.

• Journal of Pharmaceutical Investigation
• /
• 제35권6호
• /
• pp.437-443
• /
• 2005

A rapid, selective and sensitive reversed-phase HPLC method for the determination of a major metabolite of terfenadine, fexofenadine, in human serum was developed, validated, and applied to the pharmacokinetic study of terfenadine. Fexofenadine and internal standard, haloperidol were extracted from human serum by liquid-liquid extraction with acetonitrile and analyzed on a $Symmetry^{TM}$ C8 column with the mobile phase of 1% triethylamine phosphate (pH 3.7)-acetonitrile (67:33, v/v, adjusted to pH 5.6 with triethylamine). Detection wavelength of 230 nm for excitation, 280 nm for emission and flow rate of 1.0 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^{3}$ factorial design using a fixed fexofenadine concentration (50 ng/mL) with respect to its peak area and retention time. In addition, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 10-500 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of serum was 10 ng/mL, which was sensitive enough for the pharmacokinetic studies of terfenadine. The overall accuracy of the quality control samples ranged from 95.70 to 114.58% for fexofenadine with overall precision (% C.V.) being 3.53-14.39%. The relative mean recovery of fexofenadine for human serum was 90.17%. Stability studies (freeze-thaw, short-term, extracted serum sample and stock solution) showed that fexofenadine was stable during storage, or during the assay procedure in human serum. However, the storage at $-70^{\circ}C$ for 4 weeks showed that fexofenadine was not stable. The peak area and retention time of fexofenadine were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of fexofenadine in human serum samples for the pharmacokinetic studies of orally administered Tafedine tablet (60 mg as terfenadine) at three different laboratories, demonstrating the suitability of the method.

• Journal of Pharmaceutical Investigation
• /
• 제35권4호
• /
• pp.265-271
• /
• 2005

A rapid, selective and sensitive reversed-phase HPLC method for the determination of etodolac in human serum was developed, validated, and applied to the pharmacokinetic study of etodolac. Etodolac and internal standard, ibuprofen were extracted from human serum by liquid-liquid extraction with hexane/isopropanol (95:5, v/v) and analyzed on a Luna C18(2) column with the mobile phase of 1% aqueous acetic acid-acetonitrile (4:6, v/v). Detection wavelength of 227 nm and flow rate of 1.0 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^3$ factorial design using a fixed etodolac concentration $(1\;{\mu}g/mL)$ with respect to its peak area and retention time. And also, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of $0.05-40\;{\mu}g/mL$ with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of serum was 0.05 ${\mu}g/mL$, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 92.00 to 110.00% for etodolac with overall precision (% C.V.) being 1.08-10.11%. The percent recovery for human serum was in the range of 76.73-115.30%. Stability studies showed that etodolac was stable during storage, or during the assay procedure in human serum. The peak area and retention time of etodolac were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of etodolac in human serum samples for the pharmacokinetic studies of orally administered Lodin XL tablet (400 mg as etodolac) at three different laboratories, demonstrating the suitability of the method.

• Journal of Applied Biological Chemistry
• /
• 제52권4호
• /
• pp.187-194
• /
• 2009

참당귀 뿌리로부터 2종의 pyranocoumarin 성분을 분리하고 그들의 구조는 NMR 분석에 의해 각각 decursinol angelate(1), decursin(2)로 결정하였다. 이들 화합물에 대하여 hACAT 저해활성을 검정해본 결과, decursinol angelate(1)가 약한 저해활성을 나타낸 반면 decursin(2)은 hACAT1와 hACAT2에 대하여 $IC_{50}$ 값이 각각 137, $168\;{\mu}M$로서 우수한 저해활성을 나타내었다. 한편, 참당귀의 뿌리를 비롯한 꽃, 종자, 잎 등 여러부위에서 decursinol angelate(1), decursin(2)를 정량분석하였는데, 이때 LC/MS/MS(ESI, positive ion mode, MRM mode) 분석을 이용하였다. Decursinol angelate의 함량은 뿌리>잎>종자>꽃 순으로 높았으며, decursin의 함량은 뿌리>종자>꽃>잎 순으로 높게 측정되었다. 이상의 결과들은, 참당귀의 decursin이 동맥경화와 같은 심혈관 질환의 개선과 치료를 위해 유용하게 이용될 수 있음을 시사하였다. 또한 뿌리 이외에 그 동안 이용되지 않고 있던 참당귀 꽃, 잎과 같은 비상용부위에도 기능성물질인 decursin, decursinol angelate이 상당량 함유되어 있음이 구명되어 이러한 부위도 새로운 천연 기능성 소재로서 활용될 수 있음을 기대할 수 있었다.

• Journal of Pharmaceutical Investigation
• /
• 제36권2호
• /
• pp.89-95
• /
• 2006

A selective and sensitive reversed-phase HPLC method for the determination of pentoxifylline in human serum was developed, validated, and applied to the pharmacokinetic study of pentoxifylline. Pentoxifylline and internal standard, chloramphenicol, were extracted from the serum by liquid-liquid extraction with dichloromethane and analyzed on a Luna CI8(2) column with the mobile phase of acetonitrile-0.034 M phosphoric acid (25:75, v/v, adjusted to pH 4.0 with 10 M NaOH). Detection wavelength of 273 nm and flow rate of 0.8 mL/min were used. This method showed linear response over the concentration range of 10-500 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of the serum was 10 ng/mL, which was sensitive enough for pharmacokinetic studies of pentoxifylline. The overall accuracy of the quality control samples ranged from 89.3 to 92.7% for pentoxifylline with overall precision (% C.V.) being 4.1-9.2%. The relative mean recovery of pentoxifylline for human serum was 105.8%. Stability (stock solution, short and long-term) studies showed that pentoxifylline was not stable during storage. But three freeze-thaw cycles and extracted serum samples were stable. This method showed good ruggedness (within 15% C.V.) and was successfully applied for the analysis of pentoxifylline in human serum samples for the pharmacokinetic studies of orally administered $Trental^{\circledR}$ tablet (400 mg pentoxifylline), demonstrating the suitability of the method.

• The Korean Journal of Physiology and Pharmacology
• /
• 제20권2호
• /
• pp.201-211
• /
• 2016

Although the antioxidant and cardioprotective effects of NecroX-5 on various in vitro and in vivo models have been demonstrated, the action of this compound on the mitochondrial oxidative phosphorylation system remains unclear. Here we verify the role of NecroX-5 in protecting mitochondrial oxidative phosphorylation capacity during hypoxia-reoxygenation (HR). Necrox-5 treatment ($10{\mu}M$) and non-treatment were employed on isolated rat hearts during hypoxia/reoxygenation treatment using an ex vivo Langendorff system. Proteomic analysis was performed using liquid chromatography-mass spectrometry (LC-MS) and non-labeling peptide count protein quantification. Real-time PCR, western blot, citrate synthases and mitochondrial complex activity assays were then performed to assess heart function. Treatment with NecroX-5 during hypoxia significantly preserved electron transport chain proteins involved in oxidative phosphorylation and metabolic functions. NecroX-5 also improved mitochondrial complex I, II, and V function. Additionally, markedly higher peroxisome proliferator-activated receptor-gamma coactivator-$1{\alpha}$ ($PGC1{\alpha}$) expression levels were observed in NecroX-5-treated rat hearts. These novel results provide convincing evidence for the role of NecroX-5 in protecting mitochondrial oxidative phosphorylation capacity and in preserving $PGC1{\alpha}$ during cardiac HR injuries.

• 한국해양환경ㆍ에너지학회지
• /
• 제4권4호
• /
• pp.3-11
• /
• 2001

조간대와 같은 연안지역에서 해수의 토양 이동이 가지는 의미는 육상으로부터 유입되는 오염물질의 토양 이동 및 생물농축, 저서생물들의 생존에 필수적인 플랑크톤, 박테리아, 유기쇄설물, 산소, 영양염, 유기물의 생물공급, 수질 정화량 산정의 중요한 단서가 된다는 점이다. 따라서, 본 연구에서는 폐쇄성 수역과 같이 파도에너지가 비교적 작은 조간대에서 파도에 의한 해수의 침투거동을 해석하고, 파도에너지와 사면 구배의 변화에 따른 해수의 침투량 변화를 파악하고, 그 결과를 바탕으로 실제 조간대에서의 해수 침투량을 개략적으로 산정하는 것을 목적으로 하여, 모의 조간대 실험장치를 이용하여 실험을 수행한 결과, 다음과 같은 결론을 얻을 수 있었다. 폐쇄성 수역과 같은 파도에너지가 작은 조간대에서는 파도에 의해서 해수가 반원형의 형태로 토양중으로 침투하는 semi-circular mechanism은 지금까지 알려지지 않았던 새로운 침투 거동임을 알 수 있었다. 구배 또는 쇄파파고가 높아짐에 따라서 해수의 침투량이 증가하는 것을 알 수 있었다. 또한, 해수는 쇄파파고 보다는 구배의 영향을 크게 받아서 토양중으로 침투한다는 사실을 알 수 있었다. 현장토양을 이용하여 해수의 침투량을 정량화 할 수 있었으며, 본 연구의 결과를 바탕으로 현장 조간대에서의 해수 침투량을 개략적으로 산정 할 수 있었다. 따라서, 본 연구 결과를 바탕으로 오염물질의 토양 이동 및 생물농축, 저서생물들의 먹이공급, 수질 정화량 산정에 관한 연구가 활발히 진행되기를 요망한다.

• 한국동물위생학회지
• /
• 제31권3호
• /
• pp.385-395
• /
• 2008

This study was carried out to investigate the residue level of fluoroquinolones in hen's general eggs and specific eggs by microbiological assay method and high performance liquid chromatography (HPLC) method. HPLC separation was carried out by reversed phase chromatography on a Symmetry $C_{18}$ (250${\times}$4.6 mm, $5{\mu}m$ particle size) with a phase composed of distilled water (containing 0.4% triethylamine and phosphoric acid) : Methanol (780 : 220, v/v), pumped isocratically at a flow rate of 1.0ml/min. A fluorescence detector was utilized with an excitation wavelength of 278nm and an emission wavelength of 456nm. The calibration curves were linear $({\gamma}^2{\geq}0.999)$ over a concentration range of $0.025{\sim}0.4{\mu}g/ml$. Average recoveries of the five fluoroquinolones in whole eggs at fortified levels of $0.05{\sim}0.2{\mu}g/g$ were ranged mean $78.1{\sim}91.7%$ and low coefficient of variation was less than 10% for all analysed samples. The limits of detection and limits of quantification for whole eggs were $1.2{\sim}6.0ng/g$ and $2.3{\sim}9.1ng/g$, respectively. Only one hen's general eggfrom chicken farm in Incheon was detected with the residual fluoroquinolones (Microbiological assay method; 1 of 47 general eggs) ; the range of residual concentration enrofloxacin was 0.12ppm. Those in food stores were detected with the residual fluoroquinolones (Microbiological assay method; 4 of 88 general eggs) ; the ranges of residual concentration enrofloxacin were $0.15{\sim}2.2 ppm$, ciprofloxacin $0.01{\sim}0.06ppm$, and hen's specific eggs (40) in food stores were not detected. For the microbiological assay method of fluoroquinolones in hen's eggs, as the results of comparative analysis, the disc diffusion method with E coli may be a little highly detected for the residual fluoroquinolones.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권11호
• /
• pp.4549-4553
• /
• 2015

Background: Colorectal carcinoma (CRC) is one of the major causes of cancer death worldwide. Data from the literature indicate differences between the proliferation rate of endothelial cells relative to the morphology growth type, possibly due to origin of specimens (autopsy material, surgery fragments) or quantification methods. Vascular endothelial growth factor (VEGF) is a factor that stimulates the proliferation of endothelial cells. It is expressed in more than 90% of cases of metastatic CRC. Aim: The aim of this study was to evaluate the endothelial cell proliferation and VEGF expression in primary tumors and corresponding liver metastases. Materials and Methods: Our study included 24 recent biopsies of primary tumors and corresponding liver metastases of CRC cases. CD34/Ki67 double immunostaining and RNA scope assay for VEGF were performed. Results: In the primary tumors analysis of VEGFmRNA expression indicated no significant correlation with differentiation grade, proliferative and non-proliferative vessels in the intratumoral and peritumoral areas. In contrast, in the corresponding liver metastases, VEGFmRNA expression significantly correlated with the total number of non-proliferative vessels and total number of vessels. CD34/Ki67 double immunostaining in the cases with poorly differentiated carcinoma indicated a high number of proliferating endothelial cells in the peritumoral area and a low number in the intratumoral area for the primary tumor. Moderately differentiated carcinomas of colon showed no proliferating endothelial cells in the intratumoral area in half of the cases included in the study, for both, primary tumor and liver metastasis. In well differentiated CRCs, in primary tumors, a high proliferation rate of endothelial cells in the intratumoral area and a lower proliferation rate in the peritumoral area were found. A low value was found in corresponding liver metastasis. Conclusions: The absence of proliferative endothelial cells in half of the cases for the primary tumors and liver metastases in moderately differentiated carcinoma suggest a vascular mimicry phenomenon. The mismatch between the total number of vessels and endothelial proliferation in primary tumors indicate that a functional vascular network is already formed or the existence of some mechanisms influenced by other angiogenic factors.

• 한국건설관리학회논문집
• /
• 제14권1호
• /
• pp.82-90
• /
• 2013

건설 산업의 속성상 프로젝트의 성과를 정량적으로 분석하기 위해서는 다양한 영향인자에 대한 고려가 필수적이다. 프로젝트의 특성과 성과와의 관계를 파악하고, 프로젝트에 가장 적합한 관리기법을 적용시켜서 프로젝트의 성과를 향상시키기 위해서는 성과관련 정보를 축적시켜 관리하기 위한 시스템적인 접근이 요구되고 있다. 그럼에도 불구하고 많은 성과관련 시스템들은 성과결과의 분석에만 치중하여 프로젝트의 특성이나 관리기법 등 성과에 영향을 미치는 인자에 대한 심도 있는 분석방법과 접근방식에 대한 고려 부족으로 인해 성과시스템의 활발한 적용을 기대할수 없었다. 이에 본 연구는 건설 프로젝트의 특성을 고려하여 성과를 사전에 예측하고 성과체계를 정량적으로 모델링할수 있는 성과정보시스템을 개발하는 데 목적을 두었다. 이를 위해 실제 사례프로젝트의 성과관련 정보를 바탕으로 성과결과와 프로젝트 특성, 관리기법 간의 상관관계를 분석함으로써 해당 프로젝트에 가장 적합한 관리기법을 도출할수 있는 방안을 수립하였다. 그 결과, 성과영역별로 다양한 관점에서 프로젝트의 성과비교가 가능할 수 있는 정량화 방안을 정립하였고, 상관관계 분석을 통해 성과예측이 가능한 모델을 제안하였으며, 기존 데이터 분석을 통해 최적 관리기법을 선정할수 있는 시스템을 개발하였다. 웹기반 프로그램으로 구축된 시스템은 향후 데이터베이스의 지속한 관리와 보완을 통해서 성과정보의 양을 확대시킨다면 통계적으로 유의미한 결과를 바탕으로 신뢰성 있는 프로젝트 성과 관리를 도모할수 있을 것으로 사료된다.