• Title/Summary/Keyword: sample pretreatment

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Accumulation of Organonitrogen Pesticides in Fishes and Amphibians from the Basin of Major Rivers of S. Korea (우리 나라 주요 하천유역에 서식하는 양서류 및 어류의 유기질소계 농약류 축적)

  • Oh, Dong-Jin;Kim, Young-Bok;Lee, Ji-Young;Moon, Ji-Yong;Jeong, Gi-Ho
    • Analytical Science and Technology
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    • v.15 no.6
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    • pp.489-495
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    • 2002
  • In this study, we determined distribution status of organonitrogen pesticides such as trifluralin, atrazine, metribuzin, alachlor, malathion, nitrofen, permethrin, cypermethrin, fenvalerate, and parathion accumulated in the fresh water fishes and amphibians. We collected those samples at 31 sites from the basin of major rivers, and separated the muscular tissue as a final sample for analysis. In the pretreatment process, lipid was eliminated by using acetonitrile and n-hexane, and pesticides were reextracted with dichloromethane. The extract was dehydrated and concentrated, and then cleaned it up by passing the Florisil column, and pesticide content was finally determined by using a GC-MS system after introducing isotope labelled references. The accumulation level was observed in the range of $0.17{\sim}6.8{\mu}g/kg$ in amphibians and $0.26{\sim}16{\mu}g/kg$ in fishes including cypermethrin as $16{\mu}g/kg$.

Trace impurities analysis of the electronic polymer resins by neutron activation analysis (중성자방사화분석법에 의한 전자소재용 고분자수지의 불순물 분석법연구)

  • Yoon, Yoon Yeol;Cho, Soo Young;Lee, Kil Yong;Yang, Myung Kwon;Shim, Sang Kwon;Chung, Yong Sam
    • Analytical Science and Technology
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    • v.17 no.4
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    • pp.308-314
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    • 2004
  • When the polymer was used for the guard raw materials of electronic device, the content of U, Th and their daughter nuclides were known as a factor of soft error. Because emitted alpha ray could be caused of mis-operation. And ionic impurities such as Cl, Fe, Na could shorten the device life-time. For the analysis of trace impurities in the polymer, neutron activation analysis(NAA) and ICP/AES have been studied. To improve the accuracy and sensitivity of the trace and ultratrace metallic impurities in the epoxy and phenol polymer, sample pretreatment method and optimum analytical condition of NAA were developed. Using the above method, U, Th and other 23 trace impurity elements were analyzed.

Regulator of Calcineurin 1 Isoform 4 (RCAN1.4) Is Overexpressed in the Glomeruli of Diabetic Mice

  • Jang, Cho-Rong;Lim, Ji-Hee;Park, Cheol-Whee;Cho, Young-Jin
    • The Korean Journal of Physiology and Pharmacology
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    • v.15 no.5
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    • pp.299-305
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    • 2011
  • Calcineurin (CaN) is activated in diabetes and plays a role in glomerular hypertrophy and extracellular matrix (ECM) accumulation. Here, kidneys from diabetic model mice were investigated for the expression of the regulator of CaN 1 (RCAN1) isoform 4 (RCAN1.4) which had been shown to be transcriptionally upregulated by CaN activation. We found the increased immunoreactivity for RCAN1 in the glomerular cells of db/db mice and streptozotocin-induced diabetic mice. In concordance, the expression of RCAN1 protein and RCAN1.4 mRNA were elevated in the whole kidney sample from db/db mice. Interleukin-$1{\beta}$ (IL-$1{\beta}$), tumor necrosis factor-${\alpha}$, and glycated albumin (AGE-BSA) were identified as inducers of RCAN1.4 in mesangial cells. Pretreatment of cyclosporine A blocked the increases of RCAN1.4 stimulated by IL-$1{\beta}$ or AGE-BSA, suggesting that activation of CaN is required for the RCAN1.4 induction. Stable transfection of RCAN1.4 in Mes-13 mesangial cells upregulated several factors relevant to ECM production and degradation. These results suggested that RCAN1.4 might act as a link between CaN activation and ECM turnover in diabetic nephropathy.

Monitoring of Aflatoxins in Herb Medicines (한약재 중 아플라톡신 Monitoring)

  • Lee, Sung-Deuk;Kim, Yeon-Sun;Yoon, Young-Tae;Park, Ae-Sook;Shin, Young;Kim, Hwa-Soon;Kim, Yoo-Kyung;Choi, Byung-Hyun
    • Korean Journal of Medicinal Crop Science
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    • v.18 no.5
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    • pp.338-344
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    • 2010
  • Our paper shows the results of 302 samples of herb medicines about fungal contamination at Yakyeang markets in Seoul. The sample medicines were treated VICAM pretreatment and analysed by post column derivatisation procedure(PHRED-HPLC) with a fluorescence detector. Aflatoxin B1 was founded from 50.3% of samples, aflatoxin B2 was 39.7%, aflatoxin G1 was 21.2% and aflatoxin G2 was 23.5%. The detected ranges of aflatoxin B1, B2, G1 and G2 were from 0.1 to $57.2\;{\mu}g/kg$, 0.1 to $42.6\;{\mu}g/kg$, 0.1 to $23.5\;{\mu}g/kg$ and 0.1 to $9.5\;{\mu}g/kg$ respectively. Among total samples, 26 samples contained aflatoxin B1 violated the regulation (less than 10 ug/kg) for aflatoxin B1 of KFDA. From the result, we could presumed that more than a half of samples were contaminated by aflatoxins. Therefore, it seems to be necessary that the new safety giudeline will be established aflatoxin B2, G1 and G2 from herb medicines as aflatoxin B1.

Anti-stress Effects of Natural Products from Jeju Island in Zebrafish (제브라피쉬에서의 제주도 천연추출물의 항스트레스 효과)

  • Lee, Jeongwon;Lee, Seungheon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.85-85
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    • 2019
  • Objective: In this study, the anti-stress effects of extract of Hydrangeae Dulcis Folium (EHDF) or ethalonic extract of Opuntiaficus-indica (EOF) of natural extracts from Jeju Island were investigated. Methods: We performed measurement of whole-body cortisol level and behavioral experiments including the novel tank test (NTT) or the open field test (OFT) to assess stress responses in zebrafish. To induce physical stress, we used the net handling stress (NHS). Fish were treated with EOF or EHDF for 6 min before they were exposed to stress. And then, we sacrificed fish for collecting body fluid from whole-body or conducted behavioural tests, including novel tank test and open field test, were evaluated to observe anxiety-like behaviours and locomotion. We used the cortisol enzyme-linked immunoassay kit to measure the amount of cortisol in each zebrafish sample. Results: The results indicate that increased anxiety-like behaviours in novel tank test and open field test under stress were prevented by treatment with both EOF and EHDF (P < 0.05). Moreover, compared with the unstressed group, which was not treated with NHS, the whole-body cortisol level was significantly increased by treatment with NHS. Compared with the NHS-treated stressed control group, pre-treatment with each EHDF and EOF for 6 min significantly prevented the NHS-increased whole-body cortisol level (P < 0.05). Conclusions: In conclusion these results suggest that both EOF and EHDF pretreatment may prevent stress responses and that its mechanism of action may be related to its positive effects on cortisol release.

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Optimized pretreatment conditions for the environmental DNA (eDNA) analysis of Apostichopus japonicus

  • Kang, Yu-An;Lee, Soo Rin;Kim, Eun-Bi;Park, Sang Un;Lim, Sang Min;Andriyono, Sapto;Kim, Hyun-Woo
    • Fisheries and Aquatic Sciences
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    • v.25 no.5
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    • pp.264-275
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    • 2022
  • A non-destructive environmental DNA protocol for the genetic analysis of sea cucumber (Apostichopus japonicus) resources DNA was established. Among the several commercial DNA extraction kits, the DNeasy® Plant Mini Kit was selected as the best choice to obtain the high-quality genomic DNAs from the mucous sea cucumber. As the temperature and incubation time increased, the amount of extracted environmental DNA was also large, but it was judged that the increased amount did not affect as much as 2-3 times. Therefore, these conditions were not considered to be the main factors to consider in actual environmental DNA extraction. However, the amount of seawater relative to the size of the sample was judged as a major consideration, and a sufficient amount of environmental DNA for analysis was secured when stored within 1 min while stirring the volume of seawater corresponding to the total sea cucumber weight (g). In securing the environmental DNA of sea cucumbers, the mortality rate of sea cucumbers in all experiments was 0, and it was judged that the effects of sea cucumbers were not significant through this treatment. Through the results of this study, sea cucumber DNA research, which has been conducted in a destructive method, can be conducted non-destructively through environmental DNA analysis. Through this study, we have secured a standard protocol that can successfully extract the sea cucumber DNA through environmental DNA. It is not only excellent in terms of time and cost of traditional DNA analysis method currently used, but it is completely non-destructive in the ecosystem of the survey area. It is believed that the system can be transformed in a way that does not affect it. However, it is thought that various standard protocols should be established considering the characteristics of each type.

Assessment of pharyngeal airway in Korean adolescents according to skeletal pattern, sex, and cervical vertebral maturation: A cross-sectional CBCT study

  • Elagib, Tassneem;Kyung, Hee-Moon;Hung, Bui Quang;Hong, Mihee
    • The korean journal of orthodontics
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    • v.52 no.5
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    • pp.345-353
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    • 2022
  • Objective: To investigate airway volumes using cone-beam computed tomography (CBCT) by skeletal patterns, sex, and cervical vertebral maturation (CVM) stages in Korean adolescents. Methods: The sample consisted of pretreatment CBCT and cephalograms of 95 adolescents (aged 12-19) obtained out of 1,611 patients examined for orthodontic treatment from 2018 to 2020 in Kyungpook National University Dental Hospital. The samples were classified into two sex groups; three skeletal pattern groups, four chronological age groups and four CVM stages. Nasopharyngeal volumes (NPV), oropharyngeal volumes (OPV), total pharyngeal airway volume (TAV) and minimum cross-sectional area (MCA) measurements were taken from the CBCT. Multiple linear regression analyses to find out which one of the independent variables are good predictors for airway variables. Significant factors were analyzed by two-way multivariate analysis of variance (MANOVA) then multiple comparisons were analyzed using a t-test, and Fisher least significant difference. Results: Age, sex, CVM, and Sella-Nasion-B point have significant influence on airway variable. Males and females showed similar patterns of change in chronological age groups 1-3; however, males had larger NPV, OPV, and MCA at CVM in group 4. According to CVM stages, males had larger OPV, TAV, and MCA at CVM stage 6 (p-value: 0.019, 0.021, 0.015, respectively) and no sex differences at CVM stages 3, 4, and 5. Conclusions: Skeletal patterns have an effect on airway volume. Sex differences were found in CVM 6.

Mood and Emotional Changes After PEERS® Program in Parents of Young Adults With Autism Spectrum Disorder

  • Chansoo Son;Hee Jeong Yoo;Joo-Hyun Kim;Miae Oh
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.34 no.1
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    • pp.30-36
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    • 2023
  • Objectives: This study examined the changes in anxiety and depressive symptoms in the parents of Korean adults with autism spectrum disorder (ASD) after participating in the Korean version of the Program for the Education and Enrichment of Relational Skills for Young Adults (PEERS® -YA-K). Methods: Forty-six parents were enrolled (mean age 54.7 years; 22 fathers and 24 mothers), of whom 27 participated in the PEERS® - YA-K as social coaches. Participants completed self-report scales, including the Test of Young Adult Social Skills Knowledge (TYASSK), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and Symptom Check-List-90-R (SCL-90-R). The scales were administered three times: before and after the 16-week program and 4 months after the program ended. Differences between participant variables at pretreatment, post-treatment, and follow-up were analyzed using paired-sample t-tests. Results: Participants showed a significant improvement in their social skills knowledge (TYASSK) (p<0.01). There was a significant improvement in the BAI and BDI scores of parents with severe depressive and anxiety symptoms at the baseline (p<0.05). Paternal paranoia and maternal hostility results also significantly improved on the SCL-90-R. Conclusion: This study suggests that PEERS® -YA-K can reduce parental anxiety and depressive symptoms. To the best of our knowledge, this is the first to compare the degree of depression and anxiety after PEERS® -YA-K in parents of adults with ASD.

Effect of post-treatment routes on the performance of PVDF-TEOS hollow fiber membranes

  • Shadia R. Tewfik;Mohamed H. Sorour;Hayam F. Shaalan;Heba A. Hani;Abdelghani G. Abulnour;Marwa M. El Sayed;Yomna O. Mostafa;Mahmoud A. Eltoukhy
    • Membrane and Water Treatment
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    • v.14 no.2
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    • pp.85-93
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    • 2023
  • Membrane separation is widely used for several applications such as water treatment, membrane reactors and climate change. Cross-linked organic-inorganic hybrid polyvinylidene fluoride (PVDF) / Tetraethyl orthosilicate (TEOS) was adopted for the preparation of optimized hollow membrane (HFM) for membrane distillation or other low pressure separators for mechanical properties and permeability under varying pretreatment schemes. HFMs were prepared on semi-pilot membrane fabrication system. Novel adopted post-treatment schemes involved soaking in glycerol, magnesium sulphate (MgSO4), sodium hypochlorite (NaOCl), and isopropanol for different durations. All fibers were characterized for morphology using a scanning electron microscope (SEM), surface roughness using atomic force microscope (AFM), elemental composition by examining Energy Dispersive Spectroscopy (EDS), water contact angle (CA°) and porosity. The performance of the fibers was evaluated for pure water permeation flux (PWF). Post-treatment with MgSO4 gave the highest both tensile modulus and flux. Assessment of properties and performance revealed comparable results with other organic-inorganic separators, HF or flat. In spite of few reported data on post treatment using MgSO4 in presence of TEOS, this proves the potential of low cost treatment without negative impact on other membrane properties. The flux is also comparable with hypochlorite which manifests substantial precaution requirements in actual industrial use.The relatively high values of flux/bar for sample treated with TEOS, post treated with MgSO4 and hypochlorite are 88 and 82 LMH/bar respectively.

Comparative analysis of glycerin in cosmetics by LC/MS and 1H NMR (LC/MS와 1H NMR을 이용한 화장품속의 글리세린 비교분석)

  • Park, Gyo-Beom;Park, Chan Jo;Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.20 no.5
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    • pp.400-405
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    • 2007
  • The comparative analysis of glycerin in cosmetic samples was carried out by LC/MS and $^1H$ NMR spectrometry. For the LC/MS analysis, aqueous solution was controlled in strong basic condition with sodium hydroxide, and benzoyl chloride was added to the solution for the derivatization of glycerin. The derivative was extracted using pentane and analyzed by the LC/MS. For the $^1H$ NMR analysis, sample was directly dissolved in $D_2O$ solvent without pretreatment. The quantitative analysis of glycerin was done by $^1H$ NMR ERETIC method. The analysis results of LC/MS and $^1H$ NMR showed that the calibration curves were a good linearity with $r^2=0.9991$ in the range of 0.1 to $10{\mu}g/mL$ and $r^2=1$ in the range of 25 to $500{\mu}g/mL$, respectively.