• Title/Summary/Keyword: positive matrix

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Development and Validation of Analytical Method for Determination of Fungicide Spiroxamine Residue in Agricultural Commodities Using LC-MS/MS (LC-MS/MS를 이용한 농산물 중 살균제 Spiroxamine의 시험법 개발 및 검증)

  • Park, Shin-Min;Do, Jung-Ah;Lim, Seung-Hee;Yoon, Ji-Hye;Pak, Won-Min;Shin, Hye-Sun;Kuk, Ju-Hee;Chung, Hyung-Wook
    • Journal of Food Hygiene and Safety
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    • v.33 no.4
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    • pp.296-305
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    • 2018
  • Spiroxamine, one of fungicides, is used to control powdery mildew in various crops and black yellow sigatoka in bananas. The major strength of spiroxamine is to control powdery mildew in various crops and bananas yellow sigatoka in bananas. The compound has shown a high level of activity, good persistence and crop tolerance. Besides powdery mildew, good control of rust, net blotch and Rhynchosporium diseases been indicated in cereals, together with a complementary activity against Septoria diseases. In 2017, the maximum residue limit (MRL) of spiroxamine established in Korea. According to Ministry of ood and rug afety) regulations, spiroxamine residues defined only parent compound. Thus, a analytical method is needed to estimate the residue level of the parent compound. The objective of this study was to develop and validate analytical method for spiroxamine in representative agricultural commodities. Samples were extracted with acetonitrile and partitioned with dichloromethane to remove the interfering substances. The analyte were quantified and confirmed liquid chromatograph-tandem mass spectrometer (LC-MS/MS) in positive-ion mode using multiple reaction monitoring (MRM). Matrix matched calibration curves were linear over the calibration ranges ($0.0005{\sim}0.1{\mu}g/mL$) for the analyte in blank extract with coefficient of determination ($r^2$) > 0.99. For validation purposes, recovery studies will be carried out at three different concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates at each level. The recoveries 70.6~104.6% with relative standard deviations (RSDs) less than 10%. All values were consistent with the criteria ranges in the Codex guidelines (CAC/GL40, 2003) and MFDS guidelines. proposed analytical method be used as an official analytical method in the Republic of Korea.

Clinicopathologic Features and HBsAg and HBeAg Expressions in Hepatitis B Virus-associated Glomerulopathy (B형 간염 바이러스 감염과 연관된 사구체신염의 임상병리학적 특성과 신 조직내에서 HBs Ag 과 HBe Ag의 발현)

  • Jung Soo-Jin;Kim Young-Joo;Yoon Hye-Kyoung;Chung Woo-Yeong;Kim Young-Hoon;Kim Su-Yung
    • Childhood Kidney Diseases
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    • v.2 no.1
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    • pp.50-59
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    • 1998
  • Purpose : Hepatitis B virus (HBV) infection has been involved in several forms of immune-related glomerulopathy but the pathogenic role of HBV infection is not clear. To evaluate the clinicopathological features of HBV-associated glomerulopathy, a clinicopathological analysis and immunohistochemical stain for HBs Ag and HBe Ag were done. Methods : Clinicopathological features of HBV-associated glomerulopathy were analyzed with renal biopsies in 28 HBsAg seropositive patients from April 1990 to February 1997 at Pusan Paik Hospital, and immunohistochemical evaluation for HBsAg and HBeAg was done in renal tissues. Light microscopic, immunofluorescent and electron microscopic examination and immunohistochemical staining for HBsAg (DAKO) and HBeAg (BIONIKE) of renal tissue were performed. Result ; 1. The age distribution was 6 to 73 years old, and eight were children and 20 were adults. Male : female ratio was 3:1. Nineteen (67.9%) and 21 (75.0%) of 28 cases showed hematuria and proteinuria, respectively at the time of biopsy. Sixteen (57.2%) of them had nephrotic syndrome. 2. Liver function test was performed in 11 patients and seven (63.6%) of them showed increased AST and ALT levels. Liver biopsy was done in three patients and revealed findings of chronic active hepatitis. 3. HBV-associated glomerulopathy was membranous glomerulonephritis (MGN) in 10 (35.7%), mesangiopathy in 8 (28.6%), membranoproliferative glomerulonephritis (MPGN) in 7 (25.0%) and minimal change disease in 3 (10.7%) out of 28 cases. 4. Ultrastructurally HBV-associated MGN showed conspicuous subepithelial deposits with intramembranous, mesangial and subendothelial deposits and proliferation of mesangial cells and matrix, which were suggestive of MPGN. In HBV-associated MPGN, intramembranous and subepithelial deposits were scattered. 5. Immunohistochemical staining revealed no expression for HBsAg, but positive reaction for HBeAg along capillary wall in 8 cases (28.6%), of which 3 cases were checked for serum HBeAg, all showed positivity. Conclusion : HBV-associated glomerulopathy showed a wide morphologic spectrum and overlapping ultrastructural features in MGN and MPGN, and the activity of hepatitis B virus may be related to the development of HBV-associated glomerulopathy but further studies are recommended to confirm this relationship.

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Molecular Cloning of Novel Genes Specifically Expressed in Snailfish, Liparis tanakae (꼼치, Liparis tanakae에서 특이하게 발현되는 새로운 유전인자의 검색)

  • 송인선;이석근;손진기
    • Development and Reproduction
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    • v.4 no.1
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    • pp.67-77
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    • 2000
  • Snailfish usually lives at the bottom of the sea and showed typical retrogressive change with specialized tissue structures of skin and skeletons. In order to obtain the specific genes of snailfish, highly expressed in the body, we made subtracted cDNA library and analyzed 200 clones. Totally 200 clones were obtained and sequenced, and among them 62 clones were turned out to be homologous to the known gene, i.e., thioesterase (9), myosin (8), creatine kinase (7), skeletal alpha-actin (6), parvalbumin b (5), ribosomal protein (5), type I collagen (3), muscle troponin (3), dopamine receptor (2), histatin (2), and heat shock protein (2), cystatin (1), lectin (1), statherin (1), secretory carrier membrane protein (1), keratin type I (1), desmin (1), chloroplast (1), muscle tropomyosin (1), reticulum calcium ATPase (1), ribonucleoprotein (1). The remaining 138 clones were low homologous or non-redundant genes through Genbank search. Especially 5 clones were novel and specifically expressed in the body tissues of Snailfish by in situ hybridization. Therefore, we analysed these 5 clones to identify the C-terminal protein structures and motifs, and partly defined the roles of these proteins in comparison with the expression patterns by in situ hybridization. C9O-77, about 5000 bp, was supposed to be a matrix protein expressed strongly positive in epithelium, myxoid tissue, fibrous tissue and collagenous tissue. C9O-116, about 1500 bp, was supposed to be a transmembrane protein which was weakly expressed in the fibrous tissue, epithelium tissue, and myxoid tissue, but strong in muscle tissue. C9O-130, about 1200 bp, was supposed to be an intracytoplasmic molecule usually in the epithelial cells. C9O-161, about 2000 bp, was weakly expressed in epithelium, muscle tissue and myxoid tissue, but specially strong in epithelium. C9O-171, about 1000 bp, was supposed to be a transcription factor containing zinc finger like domain, which was intensely expressed in the epithelium, muscle tissue, fibrous tissue, and in collagenous tissue.

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Chemical Characteristics of PM1 using Aerosol Mass Spectrometer at Baengnyeong Island and Seoul Metropolitan Area (백령도 및 서울 대기오염집중측정소 에어로졸 질량 분석기 자료를 이용한 대기 중 에어로졸 화학적 특성 연구)

  • Park, Taehyun;Ban, Jihee;Kang, Seokwon;Ghim, Young Sung;Shin, Hye-Jung;Park, Jong Sung;Park, Seung Myung;Moon, Kwang Joo;Lim, Yong-Jae;Lee, Min-Do;Lee, Sang-Bo;Kim, Jeongsoo;Kim, Soon Tae;Bae, Chang Han;Lee, Yonghwan;Lee, Taehyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.3
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    • pp.430-446
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    • 2018
  • To improve understanding of the sources and chemical properties of particulate pollutants on the Korean Peninsula, An Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) measured non-refractory fine particle ($NR-PM_1$) from 2013 to 2015 at Baengnyeong Island and Seoul metropolitan area (SMA), Korea. The chemical composition of $NR-PM_1$ in Baengnyeong island was dominated by organics and sulfate in the range of 36~38% for 3 years, and the organics were the dominant species in the range of 44~55% of $NR-PM_1$ in Seoul metropolitan area. The sulfate was found to be more than 85% of the anthropogenic origin in the both areas of Baengnyeong and SMA. Ratio of gas to particle partition of sulfate and nitrate were observed in both areas as more than 0.6 and 0.8, respectively, representing potential for formation of additional particulate sulfate and nitrate. The high-resolution spectra of organic aerosol (OA) were separated by three factors which were Primary OA(POA), Semi-Volatility Oxygenated Organic Aerosol (SV-OOA), and Low-Volatility OOA(LV-OOA) using positive matrix factorization (PMF) analysis. The fraction of oxygenated OA (SOA, ${\fallingdotseq}OOA$=SV-OOA+LV-OOA) was bigger than the fraction of POA in $NR-PM_1$. The POA fraction of OA in Seoul is higher than it of Baengnyeong Island, because Seoul has a relatively large number of primary pollutants, such as gasoline or diesel vehicle, factories, energy facilities. Potential source contribution function (PSCF) analysis revealed that transport from eastern China, an industrial area with high emissions, was associated with high particulate sulfate and organic concentrations at the Baengnyeong and SMA sites. PSCF also presents that the ship emissions on the Yellow Sea was associated with high particulate sulfate concentrations at the measurement sites.

Development of analytical method for determination of spinetoram residues in livestock using LC-MS/MS (LC-MS/MS를 이용한 축산물 중 Spinetoram 공정시험법 개발 및 검증)

  • Ko, Ah-Young;Kim, Heejung;Do, Jung Ah;Jang, Jin;Lee, Eun Hyang;Ju, Yun Ji;Kim, Ji Young;Chang, Moon-Ik;Rhee, Gyu-Seek
    • Analytical Science and Technology
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    • v.29 no.2
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    • pp.94-103
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    • 2016
  • An analytical method was developed to determine the amount of spinetoram (spinetoram J and spinetoram L) in livestock samples. The spinetoram was extracted with acetonitrile and purified through a primary secondary amine (PSA) sorbent. The spinetoram residues were then quantified and confirmed using a liquid chromatography–tandem mass spectrometer (LC-MS/MS) in the positive ion mode using multiple reactions monitoring (MRM). Matrix-matched calibration curves were linear over the calibration ranges (0.005-0.5 mg/kg) into a blank extract with r2 > 0.994. The limits of detection and quantification were 0.002 and 0.01 mg/kg, respectively. The recovery results of spinetram ranged between 81.9-106.4% at different concentration levels (LOQ, 10LOQ, 50LOQ, n=5) with relative standard deviations (RSDs) less than 10%. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL40, 2003). An interlaboratory study was conducted to validate the method. The proposed analytical method proved to be accurate, effective, and sensitive for spinetoram determination. The method will be used as an official analytical method in Korea.

Development of Simultaneous Analytical Method for Determination of Isoxaflutole and its Metabolite (Diketonitrile) residues in Agricultural Commodities Using LC-MS/MS (LC-MS/MS를 이용한 농산물 중 Isoxaflutole과 대사산물(Diketonitrile)의 동시시험법 개발)

  • Ko, Ah-Young;Kim, Heejung;Do, Jung Ah;Jang, Jin;Lee, Eun-Hyang;Ju, Yunji;Kim, Ji Young;Chang, Moon-Ik;Rhee, Gyu-Seek
    • The Korean Journal of Pesticide Science
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    • v.20 no.2
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    • pp.93-103
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    • 2016
  • A simultaneous analytical method was developed for the determination of isoxaflutole and metabolite (diketonitrile) in agricultural commodities. Samples were extracted with 0.1% acetic acid in water/acetonitrile (2/8, v/v) and partitioned with dichloromethane to remove the interference obtained from sample extracts, adjusting pH to 2 by 1 N hydrochloric acid. The analytes were quantified and confirmed via liquid chromatograph-tandem mass spectrometer (LC-MS/MS) in positive-ion mode using multiple reaction monitoring (MRM). Matrix matched calibration curves were linear over the calibration ranges ($0.02-2.0{\mu}g/mL$) for all the analytes into blank extract with $r^2$ > 0.997. For validation purposes, recovery studies were carried out at three different concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates at each level. The recoveries were ranged between 72.9 to 107.3%, with relative standard deviations (RSDs) less than 10% for all analytes. All values were consistent with the criteria ranges requested in the Codex guideline (CAC/GL40, 2003). Furthermore, inter-laboratory study was conducted to validate the method. The proposed analytical method was accurate, effective, and sensitive for isoxaflutole and diketonitrile determination in agricultural commodities.

SEM Photomicrograph on Fluoride Concentration of Enamel by Fluoride Iontophoresis (불소이온영동에 의한 법랑질 표면 불소농도의 주사전자현미경적 관찰)

  • Jang, Jong-Hwa;Lee, Young-Soo
    • Journal of dental hygiene science
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    • v.6 no.4
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    • pp.303-307
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    • 2006
  • The objective of this study was to evaluate the effects of the topical application of fluoride by iontophoresis on the fluoride concentration in the dental enamel. Eighty-eight healthy teeth were extracted from orthodontic patients and divided into three experimental groups at 0.2 mA and 0.5 mA current and a control group. Each experimental group was further divided into three subgroups according to the application time (1, 3, and 5 min). Five to six teeth were assigned to each subgroup. Inotophoresis was performed using a 2% sodium fluoride solution and each tooth was sliced into a $3{\times}3mm$ specimen on enamel. The fluoride concentration in the enamel was measured using X-ray photoelectron spectroscopy. It was used to estimate the atomic ratio of fluoride on the enamel surface on selected samples. The specimen was observed via scanning electron microscopy as well. This finding was confirmed by the result that the fluoride ratios estimated by x-ray photoelectron spectroscopy was 2.71%, 2.87% and 3.80% after fluoride iontophoresis had been performed using a 2% sodium fluoride solution at 0.5 mA for 1, 3 and 5 min, respectively. In comparison, the fluoride ratio was 0.49% in the control group. As the current became higher and the time lapsed, the formation of irregular particles was strengthened on the enamel surface. Afterwards, the enamel surface was dissolved and new matrix was formed on the enamel. Fluorapatite was observed on the enamel after fluoride iontophoresis was performed at 0.5 mA for 5 min. The fluoride concentration tended to increase with increasing duration of iontophoresis. The study findings indicated that under proper conditions, fluoride iontophoresis has a positive effect in increasing the fluoride concentration in dental enamel.

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Relationships between Fatty Acids and Tocopherols of Conventional and Genetically Modified Peanut Cultivars Grown in the United States (미국산 전통품종과 유전자 재조합 땅콩품종의 지방산과 토코페롤의 상관관계)

  • Shin, Eui-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1618-1628
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    • 2013
  • Relationships between fatty acids and tocopherols in conventional and genetically modified peanut cultivars were studied by gas chromatography with flame ion detector and high performance liquid chromatography with fluorescence detection. Eight fatty acids and four tocopherol isomers in the sample set were identified and quantified. Oleic acid and linoleic acid are major fatty acids and the ratio of oleic and linoleic acids ranged from 1.11 to 16.26. Tocopherols contents were 6.76 to 12.24 for ${\alpha}$-tocopherol (T), 0.08 to 0.39 for ${\beta}$-T, 5.28 to 15.02 for ${\gamma}$-T, and 0.17 to 1.17 mg/100 g for ${\delta}$-T. Correlation coefficient (r) for fatty acids and tocopherols indicated a strong inverse relationship between oleic & linoleic acids (r=-0.97, P<0.05) and positive relationships between palmitic & linoleic acids (r=0.95, P<0.05) and ${\gamma}$-T & ${\delta}$-T (r=0.83, P<0.05). Principal component analysis (PCA) of fatty acids and tocopherols gave four significant principal components (PCs, with eigenvalues>1), which together account for 85.49% of the total variance in the data set with PC1 and PC2 contributing 45.27% and 21.33% of the total variability, respectively. Eigen analysis of the correlation matrix loadings of the four significant PCs revealed that PC1 was mainly contributed by palmitic, oleic, linoleic, and gondoic acids, while PC2 was by behenic acid, ${\beta}$-T, and ${\gamma}$-T. The score plot generated by PC1-PC2 identified sample clusters in the two spatial planes based on the oleic and linoleic acids. The score plot PC3-PC4 didn't separate sample groups.

The Effect of Vitamin E on Bleomycin-Induced Pulmonary Injury and Fibrosis in Rat - Comparison of Penicillamine- or Deferoxamine-Treated Group - (백서에서 Bleomycin 투여로 인한 폐손상 및 폐섬유화에 대한 Vitamin E의 영향 - Penicillamine, Deferoxamine 투여군과 비교 -)

  • Jung, Soon-Hee;Yong, Suk-Joong;Ahn, Chul-Min;Shin, Kye-Chul;Choi, In-Joon;Cho, Sang-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.2
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    • pp.184-205
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    • 1995
  • Background: Pulmonary toxicity by bleomycin has multiple mechanisms including direct tissue toxicity due to oxygen-derived free radicals and indirect toxicity through amplification of pulmonary inflammation. To evaluate the effect of chelators or free radical scavenger to lung damage induced by bleomycin, penicillamine as a copper chelator, deferoxamine as an iron chelator and vitamin E as a free radical scavenger were administered. Methods: Two hundred Wistar rats were divided into five groups: Control, bleomycin treated, bleomycin-penicillamine treated, bleomycin-deferoxamine treated, and bleomycin-vitamin E treated groups. Rats sacrificed on day 1, day 3, day 4, day 7, day 14, and day 28 after treatment. Bronchoalveolar lavage, light microscopic and immunohistologic studies for type I, III, IV collagens, fibronectin, laminin and NBD phallicidin were evaluated. Results: There was a significant increase in the total cell counts of bronchoalveolar lavage on day 1 from all treated animals and vitamin treated group showed an abrupt decrease in total cell counts with decrease of neutrophils on day 3. Bleomycin-vitamin E treated group had the least histologic changes such as pulmonary fibrosis. The alveolar basement membranes were positive for type IV collegen and laminin. Basement membranes of bleomycin, bleomycin-penicillamine, or bleomycin-deferoxamine treated groups were disrupted and fragmented on day 4 or 7. The bleomycin-vitamin E treated group had intact basement membranes until day 28. Conclusion: Bleomycin-induced pulmonary fibrosis was related to the severity of acute injury to oxygen radicals or activation of neutrophils and disruption of basement membrane. Vitamin E seemed to be the most effective antioxidant in the inhibition of bleomycin-induced pulmonary injury and fibrosis.

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Usefulness of Flow Composite Image in Raynaud Scan ($^{201}Tl$) ($^{201}Tl$을 이용한 레이노 검사에서 동적 Composite 영상의 유용성)

  • Kim, Dae-Yeon;Shin, Gyoo-Seol;Oh, Eun-Jung;Kim, Gun-Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.101-104
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    • 2010
  • Purpose: Raynaud scan is divided to flow, blood pool and local-delay image. Usually, we evaluate comparison through blood pool and local-delay image. We will evaluate about usability when comparative observe blood image and local-delay image in Raynaud scan that used $^{201}Tl$ as making flow image to one sheet of images. Materials and Methods: We have selected 29 Raynaud phenomenon patients aged 14~68 years who visited department of vascular surgery between Feb. 2008 and Aug. 2009. An intravenous injection $^{201}Tl$ of 111 MBq (3 mCi) to opposite side diagonal line limbs above an internal auditing department. Equipment used Philips gamma camera forte A-Z, and collimator used LEHR. Matrix size set up to each $64{\times}64$, $128{\times}128$, $256{\times}256$ and zoom factor used to full field. Protocol of dynamic is 2 second to 155 frames. Blood pool and delay count to 300 second. We set up ROI by a foundation to data acquired in PEGASYS processing program. Each results were analyzed with the SPSS 12.0 statistical software. Results: Each averages of count ratio (Rt / Lt) to have been given at composite image, a blood pool image, delay images analyzed at Raynaud phenomenon patients is $1.25{\pm}0.39$, $1.20{\pm}0.33$, $1.11{\pm}0.17$. The sample analysis results of blood pool image and delay image contented itself with p<0.029. Also, there don't have been each difference, and blood pool image, delay image regarding composite image was able to know. Conclusion: We were able to give help for comparison to evaluate a blood pool image and a local delay image at the Raynaud scan which used $^{201}Tl$ while making a flow image to one sheet image. Identification to be visual too was possible. If you are proceeded a researcher that there was further depth, you are more appropriate for, and you may get useful information.

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