• Title/Summary/Keyword: Reaction monitoring

Search Result 585, Processing Time 0.03 seconds

Analysis of Korean japonica rice cultivars using molecular markers associated with blast resistance genes

  • Suh, Jung-Pil;Roh, Jae-Hwan;Cho, Young-Chan;Han, Seong-Sook;Jeon, Yong-Hee;Kang, Kyung-Ho;Kim, Yeon-Gyu
    • Korean Journal of Breeding Science
    • /
    • v.40 no.3
    • /
    • pp.215-222
    • /
    • 2008
  • Fifty-two Korean japonica rice cultivars were analyzed for leaf blast resistance and genotyped with 4 STS and 26 SSR markers flanking the specific chromosome sites linked with blast resistance genes. In our analysis of resistance genes in 52 japonica cultivars using STS markers tightly linked to Pib, Pita, Pi5(t) and Pi9(t), the blast nursery reaction of the cultivars possessing the each four major genes were not identical to that of the differential lines. Eight of the 26 SSR markers were associated with resistant phenotypes against the isolates of blast nursery as well as the specific Korean blast isolates, 90-008 (KI-1113), 03-177 (KJ-105). These markers were linked to Pit, Pish, Pib, Pi5(t), Piz, Pia, Pik, Pi18, Pita and Pi25(t) resistance gene loci. Three of the eight SSR markers, MRG5836, RM224 and RM7102 only showed significantly associated with the phenotypes of blast nursery test for two consecutive years. These three SSR markers also could distinguish between resistant and susceptible japonica cultivars. These results demonstrate the usefulness of marker-assisted selection and genotypic monitoring for blast resistance of rice in blast breeding programs.

FT-IR Spectroscopic Study of Preparation of Lead Zirconium Titanate (PZT) by Sol-Gel Processing

  • 오영재;황인욱;심인보;김용록
    • Bulletin of the Korean Chemical Society
    • /
    • v.18 no.6
    • /
    • pp.588-594
    • /
    • 1997
  • Gelation time, gel structure and volatility of by-products during gelation of PZT sol-gel processing were investigated by FT-IR spectroscopy. FT-IR spectroscopic study was performed on PZT gels with the various H₂O contents (1, 2 and 3 mol) and the several types (HNO₃, NH₄OH) and amounts (0.1, 0.2 mol) of catalysts, monitoring temporal (0, 1, 3, 10 weeks, 3 months and 3 years) and thermal (100-700 ℃) changes of FT-IR spectra. The interpretation of temporal change of the spectra revealed two trends. One is under the condition of 1 mol H₂O, 1 mol H₂O+0.1 mol HNO₃, 3 mol H₂O and the other is for 1 mol H₂O+0.1 mol NH₄OH, 2 mol H₂O, 1 mol H₂O+0.2 mol HNO₃. The gel structures and the gelation times for these conditions were discussed in comparison with the reported results of SiO₂, and we suggested the reaction mechanisms for these structural characteristics. Thermal variation of FT-IR spectra was interpreted as the evolution processes of gel by investigating the evaporation of solvent and the decomposition of organic residues.

Stoichiometry and Stability of Complexes Formed between 18-Crown-6 as well as Digenzo-18-Crown-6 Ligands and a Few Metal Ions in Some Non-aqueous Binary Systems Using Square Wave Polarography

  • A. Nezhadali, Gh. Rounaghi;M. Chamasaz
    • Bulletin of the Korean Chemical Society
    • /
    • v.21 no.7
    • /
    • pp.685-689
    • /
    • 2000
  • The complexation reaction between Pb2+,TI and Cd2+ions and macrocyclic ligands, 18-crown-6 ( 18C6) and dibenzo- 18-crown-6 (DB 18C6), was studied in dimethylsulfoxide (DMSO)-nitromethane (NM) and dimethyl-formamide (DMF)-nitromethane binary system s by square wave polarography (SWP) technique. The stoichiometry and stability of the complexes were determined by monitoring the shifts in half-waves or peak potentials of the polarographic waves of metal ions against the Iigand concentration. In most cases, the stability constants of complexes increase with increasing amounts of the nitromethane in mixed binary solvents used in this study. The complexes formed between 18C6 and DB18C6 and these metal cations in all cases had a stoichiometry of 1 : 1. The results obtained show that there is an inverse relationship between the formation constant of complexes and the donor number of solvents based on a Gatmann donocity scale and the stability constants show a high sensitivity to the composition of the mixed solvent systems. A linear behavior was observed for variation of log Kf of I8C6 complexes vs the composition of the mixed solvent systems in NM/DMSO and NM/DMF,but a non-linear behavior was observed in the case of DB 18C6 complexes in these binary systems. In most of the systems investigated, the Pb2+ cation forms a more stable complex with the 18C6 than other two cations and the order of selectivity of this Iigand for cations is: Pb2+ > TI+,Cd2+.

Experiences of Emergency Surgical Treatment for a COVID-19 Patient with Severe Traumatic Brain Injury at a Regional Trauma Center: A Case Report

  • Yun, Jung-Ho
    • Journal of Trauma and Injury
    • /
    • v.34 no.3
    • /
    • pp.212-217
    • /
    • 2021
  • Various medical scenarios have arisen with the prolonged coronavirus disease 2019 (COVID-19) pandemic. In particular, the increasing number of asymptomatic COVID-19 patients has prompted reports of emergency surgical experiences with these patients at regional trauma centers. In this report, we describe an example. A 25-year-old male was admitted to the emergency room after a traffic accident. The patient presented with stuporous mentality, and his vital signs were in the normal range. Lacerations were observed in the left eyebrow area and preauricular area, with hemotympanum in the right ear. Brain computed tomography showed a contusional hemorrhage in the right frontal area and an epidural hematoma in the right temporal area with a compound, comminuted fracture and depressed skull bone. Surgical treatment was planned, and the patient was intubated to prepare for surgery. A blood transfusion was prepared, and a central venous catheter was secured. The initial COVID-19 test administered upon presentation to the emergency room had a positive result, and a confirmatory polymerase chain reaction (PCR) test was administered. The PCR test confirmed a positive result. Emergency surgical treatment was performed because the patient's consciousness gradually deteriorated. The risk of infection was high due to the open and unclean wounds in the skull and brain. We prepared and divided the COVID-19 surgical team, including the patient's transportation team, anesthesia team, and surgical preparation team, for successful surgery without any transmission or morbidity. The patient recovered consciousness after the operation, received close monitoring, and did not show any deterioration due to COVID-19.

Visual Field Defect after Taking Atorvastatin/Ezetimibe, a Case Study (Atorvastatin/ezetimibe 복합제 복용 후 발생한 시야결손 부작용 사례보고)

  • Kim, Jiyoon;Lee, Kyunggyu;Kim, Junyoung;Lee, Jung-Min;Kim, Na-Young;Lee, Mo-Se;Ji, Eunhee
    • Korean Journal of Clinical Pharmacy
    • /
    • v.29 no.2
    • /
    • pp.133-137
    • /
    • 2019
  • Atorvastatin is one of the most widely prescribed medications for dyslipidemia treatment. In Korea, post combined therapy with ezetimibe, a 73-year-old woman was reported by a community pharmacy to have experienced visual field defect, which recovered after drug discontinuation. She had never experienced this symptom before, and several studies have reported an association between use of statins and visual disorders such as blurred vision, diplopia, and cataract. Blockage of cholesterol accumulation, oxidative stress, or myopathy is expected to be a cause of this symptom. Naranjo scale, Korean causality assessment algorithm (Ver.2), and World Health Organization-Uppsala Monitoring Center (WHO-UMC) criteria were the three tools used to determine causality between the visual disorder and atorvastatin. The results represent 'probable', 'certain', and 'probable/likely' causality, respectively. Our results, in combination with a review of literature, indicate that ocular adverse effects are highly likely related to atorvastatin.

Validation of an analytical method for cyanide determination in blood, urine, lung, and skin tissues of rats using gas chromatography mass spectrometry (GC-MS)

  • Shin, Min-Chul;Kwon, Young Sang;Kim, Jong-Hwan;Hwang, Kyunghwa;Seo, Jong-Su
    • Analytical Science and Technology
    • /
    • v.32 no.3
    • /
    • pp.88-95
    • /
    • 2019
  • This study was conducted to establish the analytical method for the determination of cyanide in blood, urine, lung and skin tissues in rats. In order to detect or quantify the sodium cyanide in above biological matrixes, it was derivatized to Pentafluorobenzyl cyanide (PFB-CN) using pentafluorobenzyl bromide (PFB-Br) and then reaction substance was analyzed using gas chromatography mass spectrometer (GC/MS)-SIM (selected ion monitoring) mode. The analytical method for cyanide determination was validated with respect to parameters such as selectivity, system suitability, linearity, accuracy and precision. No interference peak was observed for the determination of cyanide in blank samples, zero samples and lower limit of quantification (LLOQ) samples. The lowest limit detection (LOD) for cyanide was $10{\mu}M$. The linear dynamic range was from 10 to $200{\mu}M$ for cyanide with correlation coefficients higher than 0.99. For quality control samples at four different concentrations including LLOQ that were analyzed in quintuplicate, on six separate occasions, the accuracy and precision range from -14.1 % to 14.5% and 2.7 % to 18.3 %, respectively. The GC/MS-based method of analysis established in this study could be applied to the toxicokinetic study of cyanide on biological matrix substrates such as blood, urine, lung and skin tissues.

Simultaneous Determination of Statins in Human Urine by Dilute-and-Shoot-Liquid Chromatography-Mass Spectrometry

  • Jang, Haejong;Mai, Xuan-Lan;Lee, Gunhee;Ahn, Jae Hyoung;Rhee, Jongsook;Truong, Quoc-Ky;Vinh, Dinh;Hong, Jongki;Kim, Kyeong Ho
    • Mass Spectrometry Letters
    • /
    • v.9 no.4
    • /
    • pp.95-99
    • /
    • 2018
  • An innovative, simple, and rapid assay method based on liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was developed and validated for the simultaneous determination of eight statin drugs in human urine. A simple sample clean-up procedure using the "dilute and shoot" (DAS) approach enabled a fast and reliable analysis. The influence of the dilution factor was investigated to ensure detectability and reduce the matrix effect. Chromatographic separation was performed on a Phenomenex Kinetex C18 column ($50{\times}3.0mm$ i.d., $2.6{\mu}m$) using an elution gradient of mobile phase A composed of 0.1% acetic acid, and mobile phase B composed of acetonitrile, at a flow rate of 0.35 mL/min. Quantitation was performed on a triple quadrupole mass spectrometer operated in multiple reaction monitoring (MRM) mode using electrospray ionization in positive ion mode. The total chromatographic run time was 15 min. The method was validated for selectivity, sensitivity, recovery, linearity, accuracy, precision, and stability. The present method was successfully applied to the analysis of Rosuvastatin in urine samples after oral administration to healthy human subjects.

A Sensitive and Rapid LC-MS/MS Method for Determination of Berberine in Human Plasma

  • Kim, Jae Hee;Mai, Xuan-Lan;Kim, Kyu Yeon;Sim, Min-Seok;Lee, So-Yeon;Seo, Hee-Won;Lee, Gunhee;Kim, Dae-Jung;Kim, Kyeong Ho
    • Mass Spectrometry Letters
    • /
    • v.10 no.2
    • /
    • pp.56-60
    • /
    • 2019
  • Coptidis Rhizoma (CR) has been used widely in traditional medicine to treat common diseases. This study aimed to develop a high-sensitivity liquid chromatography-tandem mass (LC-MS) spectrometry method for the evaluation of the pharmacokinetics of a new natural product that contain CR extract with the main bioactive compound, berberine, at trace concentrations. Human plasma samples were pretreated with methanol by a protein precipitation method. Berberine was analyzed on a Kinetex C18 column ($2.1mm{\times}50mm$, $100{\AA}$, $1.7{\mu}m$) using a mobile phase of 10 mM ammonium formate/0.1% formic acid in water (A) and acetonitrile (B) (50:50, v/v) with a flow rate of 0.25 mL/min. The analyte was detected by using electrospray ionization in positive mode with multiple reaction monitoring (MRM). The method was sensitive, with a lower limit of quantification of 1 pg/mL, which has not been previously obtained. The method was validated (over the range of 1-50 pg/mL) and applied successfully for the pharmacokinetic study of human plasma samples.

Anti-inflammatory Activity of Standardized Fraction from Inula helenium L. via Suppression of NF-κB Pathway in RAW 264.7 Cells

  • Chun, Jaemoo;Song, Kwangho;Kim, Yeong Shik
    • Natural Product Sciences
    • /
    • v.25 no.1
    • /
    • pp.16-22
    • /
    • 2019
  • Inula helenium L. is rich source of eudesmane-type sesquiterpene lactones, mainly alantolactone and isoalantolactone, which have the various pharmacological functions. In this study, we examined the inhibitory effects of nitric oxide (NO) production of hexane, methylene chloride, ethyl acetate, butanol, and water fractions from I. helenium and investigated the anti-inflammatory effect of hexane fraction of I. helenium (HFIH) in LPS-induced RAW 264.7 cells. Quantification of alantolactone and isoalantolactone from HFIH was carried out for the standardization by multiple reaction monitoring using triple quadrupole mass spectrometer. HFIH significantly inhibited inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) protein as well as their downstream products NO and prostaglandin $E_2$ ($PGE_2$) in LPS-stimulated RAW 264.7 cells. Moreover, HFIH suppressed $NF-{\kappa}B$ transcriptional activity by decreasing the translocation of p65 to the nucleus. The in vivo study further confirmed that HFIH attenuated the paw edema induced by carrageenan in an acute inflammation model. These findings suggest that HFIH may be useful as a promising phytomedicine for inflammatory-associated diseases.

Development of Colorimetric Paper Sensor for Pesticide Detection Using Competitive-inhibiting Reaction

  • Kim, Hyeok Jung;Kim, Yeji;Park, Su Jung;Kwon, Chanho;Noh, Hyeran
    • BioChip Journal
    • /
    • v.12 no.4
    • /
    • pp.326-331
    • /
    • 2018
  • Contamination by pesticides is an everincreasing problem associated with fields of environmental management and healthcare. Accordingly, appropriate treatments are in demand. Pesticide detection methods have been researched extensively, aimed at making the detection convenient, fast, cost-effective, and easy to use. Among the various detecting strategies, paper-based assay is potent for real-time pesticide sensing due to its unique advantages including disposability, light weight, and low cost. In this study, a paper-based sensor for chlorpyrifos, an organophosphate pesticide, has been developed by layering three sheets of patterned plates. In colorimetric quantification of pesticides, the blue color produced by the interaction between acetylcholinesterase and indoxyl acetate is inhibited by the pesticide molecules present in the sample solutions. With the optimized paper-based sensor, the pesticide is sensitively detected (limit of detection =8.60 ppm) within 5min. Furthermore, the shelf life of the device is enhanced to 14 days after from the fabrication, by treating trehalose solution onto the deposited reagents. We expect the paper-based device to be utilized as a first-screening analytic device for water quality monitoring and food analysis.