• Title/Summary/Keyword: $MS^n$

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Adverse Effects of Ligation of an Aberrant Left Hepatic Artery Arising from the Left Gastric Artery during Radical Gastrectomy for Gastric Cancer: a Propensity Score Matching Analysis

  • Lee, Sejin;Son, Taeil;Song, Jeong Ho;Choi, Seohee;Cho, Minah;Kim, Yoo Min;Kim, Hyoung-Il;Hyung, Woo Jin
    • Journal of Gastric Cancer
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    • v.21 no.1
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    • pp.74-83
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    • 2021
  • Purpose: No consensus exists on whether to preserve or ligate an aberrant left hepatic artery (ALHA), which is the most commonly encountered hepatic arterial variation during gastric surgery. Therefore, we aimed to evaluate the clinical effects of ALHA ligation by analyzing the perioperative outcomes. Materials and Methods: We retrospectively reviewed the data of 5,310 patients who underwent subtotal/total gastrectomy for gastric cancer. Patients in whom the ALHA was ligated (n=486) were categorized into 2 groups according to peak aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels: moderate-to-severe (MS) elevation (≥5 times the upper limit of normal [ULN]; MS group, n=42) and no-to-mild (NM) elevation (<5 times the ULN; NM group, n=444). The groups were matched 1:3 using propensity score-matching analysis to minimize confounding factors that can affect the perioperative outcomes. Results: The mean operation time (P=0.646) and blood loss amount (P=0.937) were similar between the 2 groups. The length of hospital stay was longer in the MS group (13.0 vs. 7.8 days, P=0.022). No postoperative mortality occurred. The incidence of grade ≥ IIIa postoperative complications (19.0% vs. 5.1%, P=0.001), especially pulmonary complications (11.9% vs. 2.5%, P=0.003), was significantly higher in the MS group. This group also showed a higher Comprehensive Complication Index (29.0 vs. 13.9, P<0.001). Conclusions: Among patients with a ligated ALHA, those with peak AST/ALT ≥5 times the ULN showed worse perioperative outcomes in terms of hospital stay and severity of complications. More precise perioperative decision-making tools are needed to better determine whether to preserve or ligate an ALHA.

A New Analytical Method for Erythromycin in Fish by Liquid Chromatography/Tandem Mass Spectrometry

  • Park, Mi-Jung;Park, Mi-Seon;Lee, Tae-Seek;Shin, Il-Shik
    • Food Science and Biotechnology
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    • v.17 no.3
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    • pp.508-513
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    • 2008
  • Erythromycin has been used to treat Streptococosis, Edwardsiel1osis, Vibriosis, Bacterial enteritis in the cultured fish. In this study, a rapid and effective erythromycin analysis method with new sample treatment protocol and liquid chromatography/tandem mass spectrometry (LC/MS/MS) system for fish products was developed. For the erythromycin extraction from fish muscle, the solvent mixture composed of 0.2% meta-phosphoric acid and methanol (6:4) showed good recovery rate, and the optimum extraction solvent volume was 20 mL. Erythromycin detection using LC/MS/MS were carried out under electro spray ionization (ESI) positive condition and erythromycin mass value 576.2 and 157.9. And the detection limit of the established method was 0.005 mg/kg in fish products. The recovery rate of the developed method applied to the fish species were as following, olive flounder, $87.6{\pm}5.0%$; black rockfish, $87.2{\pm}6.4%$; eel, $85.2{\pm}4.8%$; and rainbow trout, $86.0{\pm}6.2%$. In the established method in this study, the correlation of coefficient values ($R^2$) of erythromycin calibration curve (n=11) was 0.9998.

Optimization of Enzyme Digestion Conditions for Quantification of Glycated Hemoglobin Using Isotope Dilution Liquid Chromatography-Tandem Mass Spectrometry

  • Jeong, Ji-Seon
    • Mass Spectrometry Letters
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    • v.5 no.2
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    • pp.52-56
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    • 2014
  • Glycated hemoglobin (HbA1c) is used as an index of mean glycemia over prolonged periods. This study describes an optimization of enzyme digestion conditions for quantification of non-glycated hemoglobin (HbA0) and HbA1c as diagnostic markers of diabetes mellitus. Both HbA0 and HbA1c were quantitatively determined followed by enzyme digestion using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) with synthesized N-terminal hexapeptides as standards and synthesized isotope labeled hexapeptides as internal standards. Prior to quantification, each peptide was additionally quantified by amino acid composition analysis using ID-LC-MS/MS via acid hydrolysis. Each parameter was considered strictly as a means to improve digestion efficiency and repeatability. Digestion of hemoglobin was optimized when using 100 mM ammonium acetate (pH 4.2) and a Glu-C-to-HbA1c ratio of 1:50 at $37^{\circ}C$ for 20 h. Quantification was satisfactorily reproducible with a 2.6% relative standard deviation. These conditions were recommended for a primary reference method of HbA1c quantification and for the certification of HbA1c reference material.

The Design and Implementation of the Mutual Message Processing between WME Module and MLME Module for Vehicle Communication Technology (차량 통신 기술을 위한 WME 모듈과 MLME 모듈 간의 상호 메시지 처리과정 설계 및 구현)

  • Jang, Chung Ryong;Lee, Dae Sik;Lee, Yong Kwon
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.2
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    • pp.63-71
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    • 2013
  • WAVE(Wireless Access for Vehicular Environment) System is a communication technology to monitor system failure and vehicle functions and management services to prevent possible incidents of driving a vehicle. In this paper, we have designed and implemented the mutual message processing through parameter between WME management module that manages WAVE system and MLME that manages the upper layer MAC(Media Access Control) module. Also, in order to verify the validity, we have carried out experiments to compare the speed of data processing by dividing data of 1Mbyte, 2Mbyte, 3Mbyte into the packets of 2KByte and 4KByte. Experiments data processing speed of 2KByte packet were shown about 173.62ms in 1MByte, 2MByte about 352.61ms, 3MByte about 550.13ms and, data processing speed of 4KByte packet, 1MByte approximately 87.56ms, 2MByte about 177.94ms, 3MByte about 277.18ms. Therefore, in WAVE system, the mutual messages processing through the parameters between WME and MLME module can be utilized in the various service of ITS(Intelligent Transportation Systems) depending on the speed of data processing.

A Fast and Sensitive Method for the Simultaneous Determination and Quantification of Six Anionic Surfactants in Surface Water using HILIC-ESI-MS Technique

  • Dash, Upendra N.;Paul, Saroj Kumar
    • Mass Spectrometry Letters
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    • v.3 no.3
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    • pp.78-81
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    • 2012
  • The hydrophobic hydrocarbon chain and the polar sulfate group confer surfactant properties and enable them to be used as anionic surfactants. Anionic surfactants (AS) are known for their adverse impact on environment, particularly on aquatic ecosystem. In the present study a fast, sensitive and selective method for the determination and subsequent quantification of six anionic surfactants was developed using hydrophilic interactive liquid chromatography (HILIC) coupled to a electrospray ionization (ESI) mass spectrometer (MS), in the concentration range 15-20 ${\mu}g/L$. The capability of the method was established using regression analysis and ANOVA. The method performance was evaluated by analyzing real time surface water spiked with 1-dodecyl hydrogen sulfate at 15 ${\mu}g/L$. Combined efficiency of solid phase extraction and MS detection established recovery of 89% in presence of natural matrix. These results point out that HILIC coupled to multistage MS procedures can be a powerful technique for environmental applications concerning the screening of polar contaminants.

Liquid Chromatography-Tandem Mass Spectrometry Analysis of Riboflavin in Beagle Dog Plasma for Pharmacokinetic Studies

  • Jeong, Hyeon Myeong;Shin, Beom Soo;Shin, Soyoung
    • Mass Spectrometry Letters
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    • v.11 no.1
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    • pp.10-14
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    • 2020
  • Riboflavin is a water-soluble vitamin, which serves as a precursor to flavin mononucleotide and flavin adenine dinucleotide. This study aimed to develop a simple and rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis for the quantification of riboflavin in the Beagle dog plasma. This method utilized simple protein precipitation with acetonitrile and 13C4, 15N2-riboflavin was used as an internal standard (IS). For chromatographic separation, a hydrophilic interaction liquid chromatography (HILIC) column was used with gradient elution. The mobile phase consisted of 0.1% (v/v) aqueous formic acid with 10 mM ammonium formate and acetonitrile with 0.1% (v/v) formic acid. Since riboflavin is an endogenous compound, 4% bovine serum albumin in phosphate buffered saline was used as a surrogate matrix to prepare the calibration curve. The quantification limit for riboflavin in the Beagle dog plasma was 5 ng/mL. The method was fully validated for its specificity, sensitivity, accuracy and precision, recovery, and stability according to the US FDA guidance. The developed LC-MS/MS method may be useful for the in vivo pharmacokinetic studies of riboflavin.

Global Absolute Quantitation of Proteins in Human Whole Saliva by nLC-QIMS-TOF Employing MSE

  • Cho, Ha Ra;Jin, Sung Giu;Park, Jun Seo;Kim, Han Sol;Choi, Yong Seok
    • Mass Spectrometry Letters
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    • v.8 no.4
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    • pp.114-118
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    • 2017
  • While saliva can be considered as good biological fluid for monitoring biomarkers due to many advantages including its communication with blood and the non-invasive nature during its sampling, its applications to that purpose is still limited. As a part of efforts to expand the applications of saliva to the protein biomarker research, we carried out global absolute quantitation of proteins in human whole saliva (WS) by bottom-up proteomics techniques mainly based on nLC-Q-IMS-TOF employing $MS^E$. From the analyses of a pooled WS sample collected from 22 healthy Korean volunteers, 93 proteins ranging from $5.89{\times}10^1ng/mL$ (immunoglobulin heavy chain) to $1.59{\times}10^4ng/mL$ (${\alpha}-amylase$ 1) were confirmed. For the validation of the present results, human serum albumin in the same sample was quantitated by ELISA and its result was compared with that from the nLC-Q-IMS-TOF study. As a result, there was no significant difference between two results from individual approaches ($1.18{\times}10^4{\pm}0.03{\times}10^4 ng/mL$ from nLC-Q-IMS-TOF experiments vs. $1.23{\times}10^4{\pm}0.07{\times}10^4ng/mL$ from ELISA experiments, n=3, p=0.309). To our knowledge, this is the first global absolute quantitation of proteins in human whole saliva and information from the present study can be widely used as the first level reference for the discovery of new protein biomarkers from human whole saliva as well as for quantitative applications of human whole saliva proteins.

Comparison of Heart Rate Variability Indices between Obstructive Sleep Apnea Syndrome and Primary Insomnia (폐쇄성 수면무호흡 증후군과 일차성 불면증에서 심박동률 변이도 지수의 비교)

  • Nam, Ji-Won;Park, Doo-Heum;Yu, Jaehak;Ryu, Seung-Ho;Ha, Ji-Hyeon
    • Sleep Medicine and Psychophysiology
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    • v.19 no.2
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    • pp.68-76
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    • 2012
  • Objectives: Sleep disorders cause changes of autonomic nervous system (ANS) which affect cardiovascular system. Primary insomnia (PI) makes acceleration of sympathetic nervous system (SNS) tone by sleep deficiency and arousal. Obstructive sleep apnea syndrome (OSAS) sets off SNS by frequent arousals and hypoxemias during sleep. We aimed to compare the changes of heart rate variability (HRV) indices induced by insomnia or sleep apnea to analyze for ANS how much to be affected by PI or OSAS. Methods: Total 315 subjects carried out nocturnal polysomnography (NPSG) were categorized into 4 groups - PI, mild, moderate and severe OSAS. Severity of OSAS was determined by apnea-hypopnea index (AHI). Then we selected 110 subjects considering age, sex and valance of each group's size [Group 1 : PI (mean age=$41.50{\pm}13.16$ yrs, AHI <5, n=20), Group 2 : mild OSAS (mean age=$43.67{\pm}12.11$ yrs, AHI 5-15, n=30), Group 3 : moderate OSAS (mean age $44.93{\pm}12.38$ yrs, AHI 16-30, n=30), Group 4 : severe OSAS (mean age=$45.87{\pm}12.44$ yrs, AHI >30, n=30)]. Comparison of HRV indices among the four groups was performed with ANCOVA (adjusted for age and body mass index) and Sidak post-hoc test. Results: We found statistically significant differences in HRV indices between severe OSAS group and the other groups (PI, mild OSAS and moderate OSAS). And there were no significant differences in HRV indices among PI, mild and moderate OSAS group. In HRV indices of PI and severe OSAS group showing the most prominent difference in the group comparisons, average RR interval were $991.1{\pm}27.1$ and $875.8{\pm}22.0$ ms (p=0.016), standard deviation of NN interval (SDNN) was $85.4{\pm}6.6$ and $112.8{\pm}5.4$ ms (p=0.022), SDNN index was $57.5{\pm}5.2$ and $87.6{\pm}4.2$ (p<0.001), total power was $11,893.5{\pm}1,359.9$ and $18,097.0{\pm}1,107.2ms^2$(p=0.008), very low frequency (VLF) was $7,534.8{\pm}1,120.1$ and $11,883.8{\pm}912.0ms^2$ (p=0.035), low frequency (LF) was $2,724.2{\pm}327.8$ and $4,351.6{\pm}266.9ms^2$(p=0.003). Conclusions: VLF and LF which were correlated with SNS tone showed more increased differences between severe OSAS group and PI group than other group comparisons. We could suggest that severe OSAS group was more influential to increased SNS activity than PI group.

Establishment of the Analytical Method for Residual Pharmaceuticals in Raw Water Using Online Sample Preparation and High Resolution Orbitrap LC/ESI-MS (온라인 자동화 시료 전처리 및 HR Orbitrap LC/ESI-MS를 이용한 환경시료 중 잔류 의약물질 분석방법 확립)

  • Hwang, Yoonjung;Sin, Sanghee;Park, Jongsuk
    • Journal of Korean Society on Water Environment
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    • v.29 no.3
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    • pp.409-419
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    • 2013
  • In this study, the analytical method for 27 residual pharmaceuticals in raw water was developed. Online sample preconcentration/extraction and analysis with high resolution Orbitrap mass spectrometry (LC-ESI/Orbitrap MS) were performed. The calibration curves showed good linearities (above $r^2$ = 0.998) in the range of 5 ~ 1,000 ng/L. The method detection limit and the limit of quantification were 1.1 ~ 10.0 ng/L and 3.4 ~ 31.7 ng/L, respectively. Recoveries of the target compounds were between 70.1% and 115.8% (except cefadroxil, cefradine, vancomycin, and iopromide (50.2 ~ 67.0%)). The optimized analytical method can be useful to determine the residual pharmaceuticals in raw water.

Rapid Propagation of Pelagonium Inquinans Via Organogenesis from Mature Leaf Explants

  • Hwang, Sung-Jin
    • Korean Journal of Medicinal Crop Science
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    • v.14 no.2
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    • pp.92-95
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    • 2006
  • A method for plant regeneration via organogenesis from Pelagonium inquinans leaf disc has been developed. Mature leaf explants were collected from field-grown plants and used for the induction of adventitious shoot regeneration on Murashige and Skoog (MS) medium supplemented with 3% (w/v) sucrose plus plant growth regulators. Maximum shoot organogenesis, with $11.8{\pm}1.5$ shoots (98.6%) per leaf disc, was obtained with $2\;mg/l$ $N^6-benzyladenine$ (BA) and $0.5\;mg/l$ ${\alpha}-naphthyleneacetic$ acid (NAA) in 30 days. For rooting, the in vitro proliferated and elongated shoots were excised into 1.5-2 cm in length microcutting, which were plated individually on an half-strength MS (1/2MS) medium supplemented with 2% (w/v) sucrose plus various concentrations of indole-3-butyric acid (IBA). Shoots rooted with a frequency of 100% following culture on 1/2MS medium containing $0.5\;mg/l$ IBA.