• Archives of Pharmacal Research
• /
• 제27권12호
• /
• pp.1202-1206
• /
• 2004

A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC-MS/ MS) method for the determination of lithospermic acid B (LSB) in rat serum was developed. LSB and internal standard, 7-hydroxy-3-phenyl-chromen-4-one (HPC) were extracted from rat serum with methyl-tert-butyl ether at acidic pH and analyzed on a Luna $C_8$ column with the mobile phase of acetonitrile-ammonium formate (10 mM, pH 6.5) (50:50, v/v). The analytes were detected using a negative electrospray ionization tandem mass spectrometry in the multiple- reaction-monitoring mode. The standard curve was linear $(r^2 = 0.997)$ over the concentration range of 10.0-500 ng/mL. The coefficient of variation and relative error for intra- and interassay at three QC levels were 1.1~6.2% and -10.3~-2.7%, respectively. The recovery of LSB from serum sample ranged from 73.2 to 79.5%, with that of HPC (internal standard) being 75.1 %. The lower limit of quantification for LSB was 10 ng/mL using 50 ${\mu}L$ of serum sample.

• Investigative Magnetic Resonance Imaging
• /
• 제20권4호
• /
• pp.259-263
• /
• 2016

Primary diffuse large B-cell lymphoma of the seminal vesicle is an extremely rare disorder, with only two cases reported in the English literature. Here, we present imaging findings of a case of primary diffuse large B-cell lymphoma of the seminal vesicle. On transrectal ultrasonography, the mass presented as a 3.0-cm-sized heterogeneous, hypoechoic lesion in the right seminal vesicle. Computed tomography (CT) revealed a mass with rim-like enhancement in the right seminal vesicle. On magnetic resonance imaging (MRI), the tumor showed iso-signal intensity on T1-weighted images and heterogeneously intermediate-high signal intensity on T2-weighted images. The tumor showed rim-like and progressive enhancement with non-enhancing portion on dynamic scanning. Diffusion restriction was observed in the mass. On fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) imaging, a high standardized uptake value (maxSUV, 23.5) by the tumor was noted exclusively in the right seminal vesicle.

• Nuclear Engineering and Technology
• /
• 제56권1호
• /
• pp.123-131
• /
• 2024

Electron paramagnetic resonance (EPR) dosimetry for a tooth from an individual exposed is well known as retrospective dosimetry in radiological accidents. A major constraint of the conventional X-band tooth-EPR dosimetry is the necessity to extract the tooth of the exposed patient for dose assessment. In this study, to conduct the dose assessments of exposed patients through part-extraction of tooth enamel, the minimum detectable dose (MDD) of the tooth enamel was evaluated based on the amount of mass. Further, a field test was conducted via intercomparison using various dose assessment methods to verify the feasibility of X-band tooth-EPR dosimetry using the minimum mass of tooth enamel. The intercomparison results demonstrated that effective dose determination via X-band tooth-EPR dosimetry is reliable. Consequently, it was determined that the minimum mass of tooth enamel required to evaluate an absorbed dose above 0.5 Gy is 15 mg. Thus, EPR dosimetry using 15 mg of tooth enamel can be applied in the triage and initial medical response stages for patients exposed during radiological accidents. This approach represents an advancement in managing radiological accidents by offering a more efficient and less invasive method of dose assessment.

• Bulletin of the Korean Chemical Society
• /
• 제35권11호
• /
• pp.3363-3365
• /
• 2014

• Mass Spectrometry Letters
• /
• 제2권2호
• /
• pp.33-36
• /
• 2011

The misuse of anabolic androgenic steroids is of particular concern in sports and society. Thus, it is of great importance to discriminate endogenous steroids such as testosterone or testosterone prohormones from their chemically identical synthetic copies. In this study, gas chromatography-combustion/isotope ratio mass spectrometric (GC-C/IRMS) method has been developed and validated for discriminating the origin of anabolic androgenic steroids. The method involves the solid-phase extraction, enzymatic hydrolysis with ${\beta}$-glucuronidase, HPLC-fractionation for the cleanup and analysis by GC-C/IRMS. The difference(${\Delta}^{13}C$) of urinary ${\delta}^{13}C$ values between synthetic analogues and endogenous reference compounds (ERC) by GC-C/IRMS was used to elucidate the origin of steroids, and intra- and inter-day precision, specificity and isotope fractionation were evaluated. The present GC-C/IRMS method combined with HPLC cleanup was accurate and reproducible enough to be successfully applied to the test of urine sample from suspected anabolic steroid abusers.

• 전자공학회논문지SC
• /
• 제43권5호
• /
• pp.80-88
• /
• 2006

본 논문에서는 치밀 유방영상에서 mass형 암 검출을 목적으로 하는 시스템을 개발한다. 본 논문에서 제시하는 방법과 기존의 방법과의 차이점은 1) mass 영역의 중심의 위치와 반경을 영상신호의 불규칙성에 영향을 받지 않고 안정적으로 결정하는 방법을 제시하고, 2) mass형 유방암 영상에 적용하기 적합한 방사형 필터를 개발하며, 3) mass형 유방암 검출을 위해 mass 경계선의 불규칙성, mass 영역 중심부의 homogeneity, mass 영역의 이심율에 근거하여 다중 특징 함수 개발에 있다. 본 논문에서 제안한 시스템은 기존의 시스템보다 치밀 유방에 적용하였을 때 false alarm은 영상 당 1개 정도 높으나 true alarm 비율은 10%이상 향상 되었다.

• Mass Spectrometry Letters
• /
• 제12권3호
• /
• pp.66-75
• /
• 2021

Interleukin-4 (IL-4) and IL-13 are cytokines secreted by immune cells. Cytokines induce the proliferation of macrophages or promote the differentiation of secretory cells. The initiation and progression of allergic inflammatory diseases, such as asthma, are dependent on cytokines acting through related receptor complexes. IL-4 and IL-13 are N-glycoproteins. Glycan structures in glycoproteins play important roles in protein folding, protein stability, enzymatic function, inflammation, and cancer development. Therefore, the glycan structure of IL-4 and IL-13 needs to be elucidated in detail for the development of effective therapies. We report the first attempt to characterize the site-specific N-glycosylation of recombinant IL-4 and IL-13 via liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The tandem mass spectra of intact N-glycopeptides were identified using the Integrated GlycoProteome Analyzer (I-GPA) platform, which can automatically and rapidly analyze multiple N-glycopeptides, including their glycan composition and amino acid sequences. The recombinant IL-4 and IL-13 were identified with amino acid sequence coverages of 84% and 96%, respectively. For IL-4, 52 glycoforms on one N-glycosylation site were identified and quantified. In IL-13, 232 N-glycopeptides from three N-glycosylation sites were characterized, with the site Asn52 being the most extensively glycosylated (~80%). The complex glycans were the most abundant glycan on IL-4 and IL-13 (~96% and 91%, respectively), and the biantennary glycans were the most abundant in both recombinant IL-4 and IL-13 proteins.

• 대한한의학원전학회지
• /
• 제21권2호
• /
• pp.39-47
• /
• 2008

After reviewing literatures of Han dynasty or earlier that recognize tumor, bump or mass, we concluded as follows. The recognition or study on tumor, bump or mass started at least Seoju(西周) Dynasty or earlier, and academic system was developed since earlier Han Dynasty(漢代). Until Han Dynasty, main characters that recognize Tumor, bump or mass include Jong(腫), Yang(瘍), Yu(瘤), Yeong, Chang (瘡), Ong(癰), Jeo(疽), Jeok(積), Chwi(聚), Byeok(癖), Jing, and Ga, Hyeon that firstly appeared in Southern and Northern Dynasties(南北朝), and Am(癌) that firstly appeared in Song Dynasty[宋代] can also be considered as significant characters. The main perception of cancer(腫瘍) until Han Dynasty was started by understanding the concept of the word Yu(瘤) and developed through visual, tactile sensation and symptom observation of following 2 categories, One is tumor, btm1p or mass which is expressed in outer body like Yeong, Jong(腫), Chang(瘡), Yang(瘍), Ong(癰), and Jeo(疽), The other is tumor, bump or mass which is expressed internally like Jeok(積), Chwi(聚), Byeok (癖), Jing, and Ga.

• Korean Journal of Radiology
• /
• 제22권2호
• /
• pp.189-197
• /
• 2021

Objective: Muscle depletion in patients undergoing liver transplantation affects the recipients' prognosis and therefore cannot be overlooked. We aimed to evaluate whether changes in muscle and fat mass during the preoperative period are associated with prognosis after deceased donor liver transplantation (DDLT). Materials and Methods: This study included 72 patients who underwent DDLT and serial computed tomography (CT) scans. Skeletal muscle index (SMI) and fat mass index (FMI) were calculated using the muscle and fat area in CT performed 1 year prior to surgery (1 yr Pre-LT), just before surgery (Pre-LT), and after transplantation (Post-LT). Simple aspects of serial changes in muscle and fat mass were analyzed during three measurement time points. The rate of preoperative changes in body composition parameters were calculated (preoperative ΔSMI [%] = [SMI at Pre-LT - SMI at 1 yr Pre-LT] / SMI at Pre-LT x 100; preoperative ΔFMI [%] = [FMI at Pre-LT - FMI at 1 yr Pre-LT] / FMI at Pre-LT x 100) and assessed for correlation with patient survival. Results: SMI significantly decreased during the preoperative period (mean preoperative ΔSMI, -13.04%, p < 0.001). In the multivariable analysis, preoperative ΔSMI (p = 0.016) and model for end-stage liver disease score (p = 0.011) were independent prognostic factors for overall survival. The mean survival time for patients with a threshold decrease in the preoperative ΔSMI (≤ -30%) was significantly shorter than for other patients (p = 0.007). Preoperative ΔFMI was not a prognostic factor but FMI increased during the postoperative period (p = 0.009) in all patients. Conclusion: A large reduction in preoperative SMI was significantly associated with reduced survival after DDLT. Therefore, changes in muscle mass during the preoperative period can be considered as a prognostic factor for survival after DDLT.

• 천문학회보
• /
• 제38권1호
• /
• pp.60.2-60.2
• /
• 2013

We investigate several eruptive hot plasma observations by Hinode/XRT. Their corresponding EUV and/or white light CME features are visible in some events. Using those observations, we determine the mass constraints of eruptive plasma by assuming simplified geometrical structures of the plasma. In some events, their associated prominence eruptions and eruptive plasma were observed in EUV observations as absorption or emission features. The absorption feature provides the lower limit to the cold mass while the emission feature provides the upper limit to the mass of observed eruptive plasma in X-ray and EUV passbands. We compare the mass constraints for each temperature responses and find that the mass in EUV and XRT are smaller in their upper or lower limit than total mass in coronagraph. About half eruptive events in XRT have no corresponding CME, which may be due to failed eruptions or low plasma density. In addition, some events were observed by a few passbands in X-ray, which allows the determination of the eruptive plasma temperature using a filter ratio method. We present the isothermal plasma temperatures by the filter ratio method. These are possibly an average temperature for higher temperature plasma because the XRT is more sensitive in higher temperature.