• Title/Summary/Keyword: L-Met

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Syntheses and Characterizations of Serine and Threonine Capped Water-Dispersible ZnS:Mn Nanocrystals and Comparison Study of Toxicity Effects on the growth of E. coli by the Methionine, Serine, Threonine, and Valine Capped ZnS:Mn Nanocrystals

  • Lim, Eun-Ju;Park, Sang-Hyun;Byun, Jong-Hoe;Hwang, Cheong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1741-1747
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    • 2012
  • Water-dispersible ZnS:Mn nanocrystals were synthesized by capping the surface of the nanocrystals with conventional aminoacids ligands: serine and threonine. The aminoacids capped ZnS:Mn nanocrystal powders were characterized by XRD, HR-TEM, EDXS, ICP-AES and FT-IR spectroscopy. The optical properties were also measured by UV/Vis and solution photoluminescence (PL) spectroscopies in aqueous solvents. The solution PL spectra showed broad emission peaks around 600 nm with PL efficiencies of 9.7% (ZnS:Mn-Ser) and 15.4% (ZnS:Mn-Thr) respectively. The measured particle sizes for the aminoacid capped ZnS:Mn nanocrystals by HR-TEM images were about 3.0-4.0 nm, which were also supported by Debye-Scherrer calculations. In addition, cytotoxic effects of four aminoacids capped ZnS:Mn nanocrsystals over the growth of wild type E. coli were investigated. Although toxicity in the form of growth inhibition was observed with all the aminoacids capped ZnS:Mn nanocrystals at higher dose (1 mg/mL), ZnS:Mn-Met and ZnS:Mn-Thr appeared non-toxic at doses less than 100 ${\mu}g$/mL. Low biological toxicities were seen at doses less than 10 ${\mu}g$/ mL for all nanocrystals.

Purification and Characterization of Substance P-related Peptide from the Body of the African Lungfish, Protopterus dolloi

  • Kim, Chan-Hee;Kim, Eun-Jung;Go, Hye-Jin;Lee, Hyung-Ho;Hong, Yong-Ki;Kim, Hyung-Rak;Chung, Joon-Ki;Park, Jang-Su;Muneoka, Yojiro;Park, Nam-Gyu
    • Bulletin of the Korean Chemical Society
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    • v.27 no.7
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    • pp.1015-1019
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    • 2006
  • The peptide with structural similarity to mammalian substance P (M-SP) has been isolated from extract of the body of the African lungfish, Protopterus dolloi, using the rectum of the newt as the bioassay system. The primary structure of the SP-related peptide was identified as Lys-Pro-Arg-Pro-Asp-Gln-Phe-Tyr-Gly-Leu-Met-NH2 (L-SP) and contained four substitutions ($Lys^{1}\rightarrow $ Arg, $Arg^{3}\rightarrow$ Lys, $Asp^{5}\rightarrow$ Gln, and $Tyr^{8}\rightarrow$ Phe) compared with M-SP; this structure is identical to that of the peptide isolated from the gut of the Australian lungfish. Circular dichroism spectra showed that L-SP had an unordered structure in the buffer solution and phospholipid bilayers. This peptide was found to have an excitatory effect on rectal muscle tissues of newt, quail, and fish. L-SP also had a more potent vasodilatory effect on the guinea-pig aorta than that of M-SP. The identification of the peptide provides evidence that SP family, hitherto confined to mammals, have a widespread occurrence in lungfish.

Optimization of DOSL Surfactant Solution Conditions in Surfactant-Enhanced Remediation of Soil Contaminated by Toluene (톨루엔으로 오염된 토양에서 DOSL 계면활성제를 이용한 최적의 정화 조건 규명)

  • ;;Robert D. Cody
    • Journal of Soil and Groundwater Environment
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    • v.6 no.2
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    • pp.23-30
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    • 2001
  • Column tests were carried out to examine the effect of surfactant solution conditions on the surfactant-enhanced remediation of soil columns contaminated by toluene. The conditioned parameters of the surfactant solution for the column tests were concentration, pH, temperature and flow rate. The test results revealed that an optimum condition was achieved for 4% (v/v) of concentration, 10 of pH, $20^{\circ}C$ of temperature and 4 mL/min of flow rate respectively. The removal of 95% of toluene was obtained when optimal conditions of each surfactant solution parameter were simultaneously met. This was a marked improvement and removal efficiency increased by 6-19% compared to that with unadjusted conditions. The optimum range of these parameters may be useful for a surfactant-based remediation in the aquifer contaminated by toluene.

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Validation of a Selective Method for Simultaneous Determination of Doxifluridine and 5-Fluorouracil in Dog Plasma by LC-MS/MS (LC/MS/MS를 이용한 비글견의 혈장 중 Doxifluridine 및 5-Fluorouracil의 동시 분석법 Validation)

  • Kim, Ghee-Hwan;Kim, Won;Kim, Jin-Sung;Jin, Qingri;Kang, Won-Ku;Lee, Jong-Hwa;Ha, Jung-Heun;Jeong, Eun-Ju
    • Journal of Pharmaceutical Investigation
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    • v.37 no.3
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    • pp.179-186
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    • 2007
  • A simple, sensitive and selective liquid chromatographic/tandem mass spectrometric method (LC-MS/MS) was developed and validated for doxifluridine and 5-fluorouracil (5-FU) quantification in dog heparinized plasma. Sample preparation was based on liquid-liquid extraction using a mixture of isopropanol/ethyl acetate (1/9 v/v) to extract doxifluridine, 5-FU and 5-chlorouracil (5-CU, an internal standard) from plasma. Chromatography was performed on a C-18 analytical column and the retention times were 2.7, 1.5 and 1.7 min for doxifluridine, 5-FU and 5-CU, respectively with shorter analysis time within 5 min than previously reported methods. The ionization was optimized using ESI negative mode and selectivity was achieved by tandem mass spectrometric analysis by multiple reaction monitoring (MRM) using the transformations of m/z 244.8>107.6, 129.0>42.0 and 144.9>42.1 for doxifluridine, 5-FU and 5-CU, respectively. The achieved low limit of quantification was 20.0 ng/mL and the assay exhibited linear range of 20-2000 ng/mL ($R^2>0.99957$ for doxifluridine and $R^2>0.99857$ for 5-FU), using $100{\mu}L$ of plasma. Accuracy and precision of quality control samples for both doxifluridine and 5-FU met KFDA and FDA Guidance criteria of 15% for accuracy with coefficients of variation less than 15%. This method demonstrated adequate sensitivity, specificity, accuracy, precision and stability to support the simultaneous analysis of doxifluridine and 5-FU in dog plasma samples in pharmacokinetic and bioequivalence studies.

Evaluation of Bacteriological Safety for the Shellfish Growing Waters in Taean Area, Korea (충남 태안 패류생산해역에서의 세균학적 위생안정성 평가)

  • Song, Ki-Cheol;Lee, Doo-Seog;Shim, Kil-Bo;Lim, Chi-Won;Mog, Jong-Su;Byun, Han-Seok;Park, Young-Je;Cho, Ki-Chae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.3
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    • pp.155-162
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    • 2008
  • The seawater in the Taean area was surveyed to evaluate the conditions of the bay and compliance with the bacteriological criteria for a designated area for shellfish production for export. Samples of seawater were collected monthly at 34 sampling stations established in the survey area from January 2002 to December 2004. The bacterial density in the coastal area close to a pollution source located to the northeast of the survey area was higher than in the open sea to the west. The bacteriological counts in the water did not change with 16.5mm of rainfall, but increased abruptly after 65.4mm of rainfall. The total coliform and fecal coliform most probable numbers (MPNs) of 1,224 seawater samples in the survey area were <1.8-2,400 and <1.8-790 MPN/100 mL, respectively. The geometric mean and estimated 90th percentile of total coliforms were 1.9-3.4 and 2.7-26.3 MPN/100mL, respectively, and for fecal coliforms were <1.8-2.6 and 1.8-12.0 MPN/100mL, respectively. The bacteriological water quality in the Taean seawater area met the National Shellfish Sanitation Program criteria for an approved area and the Korea Shellfish Sanitation Program criteria for a designated area for shellfish production for export.

Validation of the Eddy Viscosity and Lange Wake Models using Measured Wake Flow Characteristics Behind a Large Wind Turbine Rotor (풍력터빈 후류 유동특성 측정 데이터를 이용한 Eddy Viscosity 및 Lange 후류모델의 예측 정확도 검증)

  • Jeon, Sang Hyeon;Go, Young Jun;Kim, Bum Suk;Huh, Jong Chul
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.40 no.1
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    • pp.21-29
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    • 2016
  • The wake effects behind wind turbines were investigated by using data from a Met Mast tower and the SCADA (Supervisory Control and Data Acquisition) system for a wind turbine. The results of the wake investigations and predicted values for the velocity deficit based on the eddy viscosity model were compared with the turbulence intensity from the Lange model. As a result, the velocity deficit and turbulence intensity of the wake increased as the free stream wind speed decreased. In addition, the magnitude of the velocity deficit for the center of the wake using the eddy viscosity model was overestimated while the turbulence intensity from the Lange model showed similarities with measured values.

Plasma adipocytokines and antioxidants-status in Korean overweight and obese females with dyslipidemia

  • Ha, Ae Wha;Jeong, Su Youn;Kang, Nam E;Kim, Woo Kyoung
    • Nutrition Research and Practice
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    • v.8 no.4
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    • pp.417-424
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    • 2014
  • BACKGROUD/OBEJECTIVES: It is hypothesized that obese people with dyslipidemia is more likely to have increased oxidative stress and decreased antioxidant status, in comparison with the controls who were obese without dyslipidemia. Thus, the aims of the present study were to determine the dietary intakes, plasma adipokines, and antioxidative systems between obese with dyslipidemia and obese without dyslipidemia were investigated. SUBJECTS/METHODS: Female subjects who were between 20 and 55 years old, and whose BMI was 23 or greater were recruited. Subjects who met the criteria of $BMI{\geq}23$, total cholestero ${\geq}200mg/dL$, LDL cholesterol ${\geq}130mg/dL$, and $TG{\geq}110mg/dL$ were categorized Obese with dyslipidemia. Anthropometric measurements and blood biochemical tests were conducted. The diet survey was conducted by a trained dietitian using two days of 24 hour dietary recall. The lipid peroxidation, the plasma total antioxidant capacity (TAC), the activities of antioxidantive enzymes, and various antioxidantive vitamins levels were determined. RESULTS: Plasma adiponectin and leptin levels were also determined. There were no significant differences for age, Body Mass index (BMI), and body fat (%), waist-size between two groups. Obese with dyslipidemia had significantly high levels of total cholesterol, triglyceride, LDL-cholesterol, the ratio of total cholesterol/HDL-C, and the ratio of HDL-C/LDL-C, respectively. Blood alkaline phosphatase level was statistically different between the two groups (P < 0.05). No statistical significance in dietary intake between two groups was shown. In case of obese with dyslipidemia group, the levels of GSH-Px (P < 0.05) and catalase (P < 0.05) as well as adjusted blood retinol (P < 0.05) and tocopherol level (P < 0.05) were significantly low. However, the plasma concentration of leptin was significantly high (P < 0.05). CONCLUSIONS: Obesity with dyslipidemia was shown to have high arthtrogenic index, depleted antioxidant status, and higher blood leptin levels which suggest higher risks of oxidative stress and cardiovascular diseases.

Verification of the Reliability and Validity of the Short Form 36 Scale in Indonesian Middle-aged and Older Adults

  • Arovah, Novita Intan;Heesch, Kristiann C.
    • Journal of Preventive Medicine and Public Health
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    • v.53 no.3
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    • pp.180-188
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    • 2020
  • Objectives: The Short Form 36 (SF-36) questionnaire is increasingly being used to measure health-related quality of life (HRQoL) in Indonesia. However, evidence that it is valid for use in Indonesian adults is lacking. This study assessed the validity and reliability of the SF-36 in Indonesian middle-aged and older adults. Methods: Adults aged 46-81 years (n=206) in Yogyakarta, Indonesia completed the SF-36, another measure of HRQoL (the EuroQoL visual analogue scale [EQ-VAS]), and measures assessing their demographic characteristics. Fifty-four percent (n=121) completed the SF-36 measure again 1 week later. Confirmatory factor analysis was conducted to confirm the factor structure of the SF-36. Internal consistency reliability was estimated using Cronbach's alpha, and test-retest reliability was assessed using intraclass correlations. Convergent and discriminant validity were assessed by computing correlations among SF-36 subscales, between subscales and the 2 component scores, and between component scores and EQ-VAS scores. Results: Most scaling assumptions were met. The hypothetical factor structure fit the data poorly (root mean square error of approximation [RMSEA]=0.108) and modification was required for a good fit (RMSEA=0.060). Scores on all subscales demonstrated acceptable internal consistency (α>0.70) and test-retest reliability (r>0.70). Divergent validity was supported by weak to moderate interscale correlations (r=0.19 to 0.64). As expected, the 2 summary scores were moderately to strongly correlated with the EQ-VAS (r>0.60). Conclusions: The findings adequately support the use of SF-36 in Indonesian middle-aged and older adults, although the optimal algorithm for computing component scores in Indonesia warrants further investigation.

Performance Evaluation of Soil Media for Water Quality Purification at LID Application (분산형 빗물관리시설 적용을 위한 수질정화기능 여재 성능 평가)

  • Park, Chan Gi;Kim, Chun Soo;Kim, Hwang Hee;Yoo, Sung-Yeol;Jeon, Ji Hong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.56 no.6
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    • pp.85-91
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    • 2014
  • In this study, the water quality purification of new medias which were NPS media, hyugato, mineral stone, charcoal for applying soil media of Integrated Management Practices (IMPs) of Low Impact Development (LID) were evaluated. The influent concentrations of COD, T-N, and T-P were 117.8 mg/L, 17.1 mg/L, and 2.062 mg/L, respectively. The infiltration capacities of NPS media, hyugoto, mineral stone, charcoal, and gravel were $7.1{\times}10m/s$, $7.3{\times}10^{-5}m/s$, $7.9{\times}10^{-5}m/s$, $6.0{\times}10^{-5}m/s$, respectively. All media meet criteria of infiltration capacity as surface soil layer at IMPs which is over $1.0{\times}10^{-5}m/s$. Maximum removal rates of COD, T-N, and T-P occurred at Charcoal with 98 % of COD removal rate, NPS with 78 % of T-N removal rate, and hyugato with 75 % fo T-P removal rate, respectively. For more high removal efficiency of all water quality item, the mixed media which is 4.5(NPS media): 1(charcoal) : 4.5 (hyugato) as volume ratio was evaluated. The infiltration capacity of mixed media was $7.9{\times}10^{-5}m/s$ and met the criteria of infiltration as surface soil layer. The water quality removal efficiencies of mixed media were very high with showing 70 % for COD, 85 % for T-N, and 71 % for T-P. The mixed media could purify the water quality of surface runoff and was recommended to used at the LID site of ground water quality problem.

Pentafluorophenylprophyl Ligand-based Liquid Chromatography-Tandem Mass Spectrometric Method for Rapid and Reproducible Determination of Metformin in Human Plasma

  • Yang, Jeong Soo;Oh, Hyeon Ju;Jung, Jin Ah;Kim, Jung-Ryul;Kim, Tae-Eun;Ko, Jae-Wook;Lee, Soo-Youn;Huh, Wooseong
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3284-3288
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    • 2013
  • This paper describes first development and validation of pentafluorophenylprophyl ligand-based liquid chromatography coupled to tandem mass spectrometry (PFPLC-MS/MS) method to determine metformin, a highly polar compound, in human plasma. Metformin and Phenformin (internal standard) were extracted from human plasma 50 ${\mu}L$ with a single-step protein precipitation. The chromatographic separation was performed using a linear gradient elution of mobile phase involving 5.0 mM ammonium formate solution with 0.1% formic acid (A) and acetonitrile (B) over 3.0 min of run time on a Phenomenex Luna PFP column. The detection was performed using a triple-quadrupole tandem mass spectrometer (Waters Quattro micro) with electrospray ionization in the mode of positive ionization and multiple-reaction monitoring (MRM). The developed method was validated with 5.0 ng/mL of lower limit of quantification (LLOQ). The calibration curve was linear over 5-3000 ng/mL of the concentration range ($R^2$ > 0.99). The specificity, selectivity, carry-over effect, precision, accuracy and stability of the method met the acceptance criteria. The method developed in this study had had rapidness, simplicity and ruggedness. The reliable method was successfully applied to high throughput analysis of real samples for a practical purpose of a pharmacokinetic study.