• 약학회지
• /
• 제57권6호
• /
• pp.412-419
• /
• 2013

Drug discovery and development processes are time consuming and costly endeavors. It has been reported that on average it takes 10 to 15 years and costs more than $ 1billion to bring a molecule from discovery to market. Compounds fail for various reasons but one of the significant reasons that accounts for failures in clinical trials is poor prediction/understanding of pharmacokinetics and drug metabolism in human. In an effort to improve the number of compounds that exhibit optimal absorption, distribution, metabolism, elimination (ADME), and pharmacokinetic properties in human, drug metabolism, pharmacokinetic scientists have been continually developing new technologies and compound screening strategies. Over the last few years, accelerator mass spectrometry (AMS) and its applications to preclinical/clinical pharmacokinetics and ADME studies have significantly increased, particularly for new chemical/biological entities that are difficult to support with conventional radiolabel studies. In this review, the application of AMS for micro-dosing, micro-tracer absolute bioavailability, mass balance and metabolite profiling studies will be discussed.

• Mass Spectrometry Letters
• /
• 제13권4호
• /
• pp.106-114
• /
• 2022

A rapid and reliable approach to the identification of microorganisms is a critical requirement for large-scale culturomics analysis. MALDI-TOF MS is a suitable technique that can be a better alternative to conventional biochemical and gene sequencing methods as it is economical both in terms of cost and labor. In this review, the applications of MALDI-TOF MS for the comprehensive identification of microorganisms and bacterial strain typing for culturomics-based approaches for various environmental studies including bioremediation, plant sciences, agriculture and food microbiology have been widely explored. However, the restriction of this technique is attributed to insufficient coverage of the mass spectral database. To improve the applications of this technique for the identification of novel isolates, the spectral database should be updated with the peptide mass fingerprint (PMF) of type strains with not only microbes with clinical relevance but also from various environmental sources. Further, the development of enhanced sample processing methods and new algorithms for automation and de-replication of isolates will increase its application in microbial ecology studies.

• Ocean and Polar Research
• /
• 제28권4호
• /
• pp.385-393
• /
• 2006

Screening performance of the existing intake screens (drum and travelling screen) on mass impingement of marine animals, a euphausiid, Euphausia pacifica and a scyphozoan medusae, Aurelia aurita that have often clogged intake screens of the Uljin Nuclear Power Plant, was tested. The maximum tolerable densities of marine animals in the inflowing seawater upon the screen were estimated with two different approaches. First the maximum density of jellyfish was calculated from (1) passing amount of seawater per unit time through the screens and (2) the covered area of animals on the screens clogged. The maximum density of krill tolerable in the drum screen was cited from a simulated record of Uljin NPP, then those in the travelling screens were also calculated using the data of drum screen and ratio of seawater amount passing through the screens under the condition of 0.5m water column (W.C.) of the differential pressure (AP) produced by screens, an established permissible limit of ${\Delta}P$. Secondly, the screening performances were also tested by hydrodynamic measurements with various screen models in a circulating water channel equipped with a speed-controlling pump and a differential pressure gauge. From the first approach, the maximum tolerable densities of drum and travelling screen were calculated as 2.0 and $1.5ind/m^3$ for the Jellyfish and 900 and $680ind./m^3$ for the euphausiid, respectively. These densities estimated from the second approach were 2.1 and $0.8ind/m^3$ for the jellyfish and 1059 and $504ind/m^3$ for the euphausiid, respectively. These estimates were compared with the data from historic clogging events to evaluate the practical performance of these intake screens. The comparisons suggest a newly improved intake-screen of which performance should be at least seven times (approximately) better than the existing ones ior the krill and 3.2 times for the jellyfish, respectively, for preventing mass impingement, and for maintaining the condition of the differential pressure between the screens below 0.3 m W.C.

• Childhood Kidney Diseases
• /
• 제6권1호
• /
• pp.61-67
• /
• 2002

목 적 : 학교 신체검사에서 우연히 발견된 단독 단백뇨를 가진 학생들의 정밀검사와 추적 관찰 결과를 분석하여 단독 단백뇨의 원인을 규명하고 향후 치료와 추적관찰에 도움을 주고자 하였다. 대상 및 방법 : 1990년 1월부터 2001년 7월까지 학교 신체검사에서 발견된 단백뇨를 주소로 서울 아산병원 소아과 외래를 방문한 학생 중 단독 단백뇨로 진단받은 초, 중, 고등학생 114명을 대상으로 하여 후향적으로 의무기록을 검토하였다. 곁 과 : 114명의 대상 학생들의 단백뇨 정량에서 일시적 단백뇨가 36례($32\%$), 기립성 단백뇨가 74례($65\%$), 지속성 단백뇨가 4례($3\%$)였다. 기립성 단백뇨군에서는 주간 단백뇨 $319.2{\pm}189.1\;mg/dL$, 야간 단백뇨 $56.5{\pm}56.1\;mg/dL$였고, 지속성 단백뇨에서는 주간단백뇨 $1140.0{\pm}540.5\;mg/dL$, 야간 단백뇨 $289.0{\pm}58\;mg/dL$였다. 모든 대상 학생들에게서 혈청 크레아티닌, 혈청 알부민, 혈청 보체 수치가 정상 범위였다. 추적 관찰결과 기립성 단백뇨군 74례 중 44례가 6개월에 추적 관찰 되었다. 이중 14례는 단백뇨가 소실되어 더 이상 추적 관찰하지 않았고, 28례는 기립성 단백뇨 소견이 지속되었다. 이중 13례가 18개월에 추적 되었으며 12례는 계속 기립성 단백뇨로 분류되었고 1례가 지속성 단백뇨 소견을 보였으나, 30개월 추적에서는 다시 기립성 단백뇨 소견을 보였다. 6개월 추적에서 2례에서 지속성 단백뇨의 소견을 보였고, 이중 1례는 30개월 까지 단백뇨가 지속되어 신 조직검사를 시행하였으나 곁과는 정상이었다. 지속성 단백뇨를 보인 4례 중 2례가 30개월에 추적 관찰되었고, 1례는 기립성 단백뇨 소견을 보였으나 1례는 지속성 단백뇨 소견을 보여 신장 조직 검사를 시행하였고, 조직 검사 결과 국소 분절성 사구체 신염(focal segmental glomerulosclerosis)으로 진단되었다. 결 론 : 학교 신체검사에서 발견된 단독 단백뇨의 대부분은 일시적인 단백뇨이거나 기립성 단백뇨이기 때문에 초기 검진시 과다한 검사는 불필요하며 정량적인 단백뇨 검사의 정기적인 추적관찰이 필요할 것으로 생각된다.

• Clinical and Experimental Pediatrics
• /
• 제51권8호
• /
• pp.787-791
• /
• 2008

Enlargement of organs or other solid tissues usually presents as an abdominal mass. Often, abdominal masses in children are found by an unsuspected parent or by a physician during a routine examination. Most masses have no specific signs or symptoms. Abdominal masses in children require immediate attention. History and physical examination may provide clues to the diagnosis. Ultrasound examination is the most useful screening test in most cases and may identify the organ involved and clarify whether the mass is solid or cystic. CT may be necessary to make a more precise diagnosis, especially solid masses. MRI is occasionally is helpful for specific abnormalities.

• Preventive Nutrition and Food Science
• /
• 제6권4호
• /
• pp.244-246
• /
• 2001

Angiotensin converting enzyme (ACE) inhibitor acts on the inhibition of ACE and causes a decrease in blood pressure. There have been several reports on screening of ACE inhibitors from natural food products and protein hydrolysates of various food sources. Ripe Cucurbita moschata Duch has been used as an oriental medicine in Korea. To isolate ACE inhibitors, crude water extracts of the edible portion of ripe Cucurbita moschata Duch were obtained after heating in water at 95$^{\circ}C$ for 2 h. Crude extracts were then filtered using PM-10 and YM-1 membranes. The membrane-filtered solution was loaded onto Sephadex G-15 column equlibrated with a phosphate buffer. Among the four major fractions of gel permeation chromatography, the second fraction had the highest inhibitory activity of 65%. Further purification of the fraction using reversed-phase HPLC with a $C_{18}$ column produced ACE inhibitors, which were identified as a mixture having molecular mass of 222 and 273 by Tandem mass spectrometry.

• Journal of Yeungnam Medical Science
• /
• 제29권1호
• /
• pp.48-53
• /
• 2012

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths in South Korea. To decrease its mortality rate, its early detection is very important. Screening for HCC detection has been accepted as the management modality for patients with chronic liver disease. Reported herein is a case involving the marked rapid growth of HCC detected at an advanced stage in a screening test with a 3 months interval. A 49-year-old male patient with chronic hepatitis B was admitted to the hospital due to a liver mass detected on CT scan. The patient underwent a first CT scan 3 months earlier, and no tumor was detected. Follow-up CT scan was performed and showed a 9.1 cm HCC with portal vein thrombosis. Percutaneous liver biopsy was performed, and the diagnosis of hepatocellular carcinoma was confirmed. In the pertinent guidelines, the recommended screening interval for HCC is 6-12 months, but the screening interval and additional diagnostic methods should be considered due to the variation in the HCC growth rate according to the patient's clinical characteristics.

• 품질경영학회지
• /
• 제43권3호
• /
• pp.273-288
• /
• 2015

Purpose: In this study, we apply environmental stress screening (ESS) to battle management system (BMS) of a tank and use the ESS profile based on production process data, guided by MIL-HDBK-781/344/2164. Methods: To optimize ESS Profile of the BMS of a tank, we estimate ESS model parameters (e.g., defect density, screening strength) using primary production failure reporting and corrective action system (FRACAS) data of military supply contract firm. Results: First, we collect the Primary production FRACAS data of military supply contract firm. Second, we compute curve fitting approach to find patent defect density and latent defect density using FRACAS data. Third, we solve the equation of Defect Density(patent defect density + latent defect density)($D_{IN}$) and Screening Strength(SS) Using second step data. As a result of analysis according to the order, we calculate $D_{IN}$(Temperature stress case : 74.02, Vibration stress : 10.252) and : SS(Temperature stress case : 0.4632, Vibration stress : 0.4142) and confirm the Condition II-D based on MIL-HDBK-344. According to Condition II-D, it is necessary to modify existing ESS profile through decreasing the $D_{IN}$ and increasing the SS. Conclusion: Identification of defect causes through ESS approach reduce defect densities for production. It provides feedback to a lessons-learned data base to avoid similar problems on next generation tank BMS.

• Journal of Preventive Medicine and Public Health
• /
• 제48권1호
• /
• pp.48-52
• /
• 2015

Objectives: This retrospective cohort study aimed at calculating some parameters of changes in the findings of the subsequent screening mammography (SSM) in female Korean volunteers. Methods: The study included screenees aged 30 to 79 years who underwent SSM voluntarily after testing negative in the baseline screenings performed between January 2007 and December 2011. A change to a positive result was defined as category 4 or 5 by using the American College of Radiology Breast Imaging Reporting and Data System. The proportion of results that had changed to positive (CP, %) was calculated by dividing the number of cases with results that were positive in the SSM by the total number of study participants. The rate of results that had changed to positive (CR, cases per 100 000 screenee-months) was calculated by dividing the number of cases with results that were positive in the SSM by the total number of months of the follow-up period. Results: The overall CP and CR in all age groups (n=77 908) were 2.26% and 93.94 cases per 100 000 screenee-months, respectively. The median CP interval in the subjects who had positive SSM results was 30 to 36 months, while that in the age group of 30 to 39 years was shorter. Conclusions: Different screening intervals should be considered among women aged between 30 and 59 years. In addition, a strategy for a screening program should be developed for the age group of 30 to 39 years, in particular.

• 농약과학회지
• /
• 제6권3호
• /
• pp.202-208
• /
• 2002

피에서 분리한 Fusarium oxysporum균주로부터 여러 번의 chromatography를 통하여 좀개구리밥의 생장을 억제하는 물질을 분리하였다. 질량분석과 핵자기공명분석을 통하여 이 물질은 dehydrofusaric acid로 동정되었다. Dehydrofusaric acid는 좀개구리밥의 생장에 대한 $EC_{50}$ 값이 $1.5{\mu}g/ml$로 매우 활성이 높은 것으로 나타났다. 또한 이 물질은 식용피, cress, 강피 및 동진벼의 뿌리의 생장도 억제하였으나, 식용피와 cress의 발아 및 네 가지 식물의 지상부의 생장에는 전혀 영향을 주지 않았다.