• Analytical Science and Technology
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• v.30 no.1
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• pp.10-19
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• 2017

Anabolic steroids have similar structures to testosterone, both of which promote the growth of muscle mass and increase strength. However, the side effects of anabolic steroid use may lead to heart attacks or strokes. Additionally, the excessive use of steroids inhibits the production of the sex hormones in the body via a negative feedback loop, which results in testicular atrophy in males and amenorrhea in females. Currently, the method of choice used to test for the presence of anabolic steroids is GC-MS. However, GC-MS methods require chemical derivatization of the steroid sample to ensure compatibility with the analytical method; therefore, analysis of many different samples is difficult and time consuming. Unlike GC-MS, the liquid chromatography-quadrupole-time of flight mass spectrometry (LC-Q-TOF-MS) method is suitable for many samples. Twenty-two different anabolic steroids were analyzed by LC-Q-TOF-MS with various collision energies (CE). Accurate mass spectral data were obtained using a Q-TOF-MS equipped with an electro-spray ionization source and operated in the positive MS/MS mode for several classes of steroids that are often the targets of testing. Based on the collected data, fragmentation pathways were carefully elucidated. The high selectivity and sensitivity of the LC-Q-TOF-MS instrument combined with these fragmentation pathways offers a new approach for the rapid and accurate screening of anabolic steroids. The obtained data from the 22 different anabolic steroids will be shared with the scientific community in order to establish a library to aid in the screening of illegal anabolic steroids.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.5-13
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• 2015

A chromatographic method for the determination of imazapyr, a non-selective herbicide, in agricultural commodities was developed to use safety control of pesticide residue on crops, and was fully validated as an official method for residue analysis. Agricultural commodities, mandarin (fruit), hulled rice (cereal grains), pepper (vegetables), potato (potatoes) and soybean (beans) were extracted with methanol and partitioned with dichloromethane to remove the interference obtained from sample extracts, adjusting pH to 2.5 by 4N hydrochloric acid. Finally, they were analyzed by high performance liquid chromatography coupled to UV detector (HPLC-UVD). The developed method had the linearity in the range of test concentrations with coefficients of determination ($r^2$) more than 0.99. Recovery studies were carried out at three concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates at each level. Recoveries were ranged between 72.1 to 108.0%, with relative standard deviations less than 10%. A consistent recovery was determined according to the CODEX guidelines (CAC/GL40, 2003). Finally, LC/MS with selected ion monitoring was also applied to confirm the suspected residues of imazapyr in agricultural samples. This developed method for determination of imazapyr residues in agricultural commodities. can be used as an official method.

• International Journal of Stem Cells
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• v.16 no.3
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• pp.281-292
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• 2023

Background and Objectives: Human induced pluripotent stem cell (hiPSC)-derived cardiomyocyte (CM) hold great promise as a cellular source of CM for cardiac function restoration in ischemic heart disease. However, the use of animal-derived xenogeneic substances during the biomanufacturing of hiPSC-CM can induce inadvertent immune responses or chronic inflammation, followed by tumorigenicity. In this study, we aimed to reveal the effects of xenogeneic substances on the functional properties and potential immunogenicity of hiPSC-CM during differentiation, demonstrating the quality and safety of hiPSC-based cell therapy. Methods and Results: We successfully generated hiPSC-CM in the presence and absence of xenogeneic substances (xeno-containing (XC) and xeno-free (XF) conditions, respectively), and compared their characteristics, including the contractile functions and glycan profiles. Compared to XC-hiPSC-CM, XF-hiPSC-CM showed early onset of myocyte contractile beating and maturation, with a high expression of cardiac lineage-specific genes (ACTC1, TNNT2, and RYR2) by using MEA and RT-qPCR. We quantified N-glycolylneuraminic acid (Neu5Gc), a xenogeneic sialic acid, in hiPSC-CM using an indirect enzyme-linked immunosorbent assay and liquid chromatography-multiple reaction monitoring-mass spectrometry. Neu5Gc was incorporated into the glycans of hiPSC-CM during xeno-containing differentiation, whereas it was barely detected in XF-hiPSC-CM. Conclusions: To the best of our knowledge, this is the first study to show that the electrophysiological function and glycan profiles of hiPSC-CM can be affected by the presence of xenogeneic substances during their differentiation and maturation. To ensure quality control and safety in hiPSC-based cell therapy, xenogeneic substances should be excluded from the biomanufacturing process.

• YAKHAK HOEJI
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• v.54 no.2
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• pp.142-149
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• 2010

Development of alternative testing methods for the replacement of hazardous reagents with less hazardous ones is strongly enforced because exposure of human and environment to hazardous reagents are restricted and hazardous reagents are gradually prohibited from using in various testing methods. Thus, in this study, we developed 8 monographs from the Korean Pharmaceutical Codex by substituting the use of the hazardous reagents including ICH class 1 such as benzene, chloroform and dioxane to the use of less toxic ones like ICH class 2 or 3 reagents. We also improved their qualification and quantification performance. Among 8 monographs, the 6 newly developed TLC methods for the identification of nifedipine, oxolamine citrate, ketoprofen lysinate, chlorquinaldol, retinol acetate, and riboflavin showed a clear spot of corresponding material without any interference in spite of the replacement with ICH class 2 or 3 reagents. For the quantification of domperidone and trimebutine, HPLC methods were developed for the substitution of UV/VIS spectrometry and titrimetry, respectively. These HPLC methods were validated for the linearity, recovery, reproducibility, and inter-laboratory variations. In conclusion, the newly developed methods could be expected to become valuable tools for revising the Korean Pharmaceutical Codex.

• Safe Food
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• v.9 no.1
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• pp.28-33
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• 2014

• Quality Improvement in Health Care
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• v.1 no.1
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• pp.44-54
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• 1994

A drug use evaluation (DUE) program has been defined as an "authorized a quality assurance process designed to ensure that drugs are used appropriately, safely, and effectively". A retrospective DUE study on ceftazidime has been conducted by reviewing patients charts following criteria for drug use evaluation established by Am.S.Hosp.Pharm. Total 60 charts of patient treated with ceftazidime in Seoul National University Hospital from Jan. 1.1993 to July.31.1993 were retrospectively reviewed. As a result, 44 cases(73%) were met with the criteria for the justification of use. In analysing process indicators including culture and sensitivity test, CBC, LFT, history of anaphylaxis monitoring before initial dose, vital sign monitoring were relatively well documented showing the accepted level above 80%, while appropriated dose were infrequently documented with low accepted level. In outcome analysis, blood culture after discontinuing drug were rarely documented, with accepted level of 46%. For using effectively and safely, ceftazidime is recommended to be administrated to optimal indication, and monitored actively for preventing adverse effect.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.220-227
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• 2021

Fluoroimide is a fungicide and is also used as a pesticide for persimmons and potatoes. The established fluoroimide pesticide analysis method takes a long time to perform and uses benzene, a carcinogen. In addition, a lower limit of quantification is required due to enforcement of the Positive List System. Therefore, this study aimed to improve the analysis method for residual fluoroimide to resolve the problems associated with the current method. The analytical method was improved with reference to the increased stability of fluoroimide under acidic conditions. Fluoroimide was extracted under acidic conditions by hydrogen chloride (4 N) and acetic acid. MgSO₄ and NaCl were used with acetonitrile. C₁₈ (octadecylsilane) 500 mg and graphitized carbon black 40 mg were used in the purification process. The experiment was conducted with agricultural products (hulled rice, potato, soybean, mandarin, green pepper), and liquid chromatograph-tandem mass spectrometry was used for the instrumental analysis. Recovery of fluoroimide was 85.7-106.9% with relative standard deviations (RSDs) of less than 15.6%. This study reports an improved method for the analysis of fluoroimide that might contribute to safety by substituting the use of benzene, a harmful solvent. Furthermore, the use of QuEChERS increased the efficiency of the improved method. Finally, this research confirmed the precise limit of quantification and these results could be used to improve the analysis of other residual pesticides in agricultural products.

• Korean Journal of Clinical Pharmacy
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• v.33 no.1
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• pp.22-34
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• 2023

Background: With the increasing use of narcotic analgesics, the Ministry of Food and Drug Safety has been operating the National Narcotics Information Management System (NIMS) since 2018 in Korea. Some studies are related to the narcotic analgesics use, but the evaluation studies of system, including NIMS users are insufficient. Objective: This study evaluated the NIMS enforcement process through in-depth interviews on the experience of using NIMS of doctors and pharmacists who prescribe or dispense opioid analgesics. Methods: Participants in this study were selected through purposeful sampling as three doctors and two pharmacists in the metropolitan area. The interviews were conducted from August 27 to October 19, 2022. Each interview was analyzed using a phenomenological method. Results: Six components of this study included "Doctors and pharmacists come across drug abusers", "They respond individually to drug abusers", "They use NIMS tailored to the needs of system managers", "They are concerned about the role of NIMS in practice settings", "They face challenges against drug abusers" and "They find a way to utilize the system to deal with drug abusers." The interviews confirmed that doctors and pharmacists used NIMS little in their work, and they only reported data. Therefore, it might be difficult for doctors and pharmacists to take measures for the safe use of narcotic analgesics. Conclusion: It is likely that adding data-feedback and medication-check function can reduce the abuse of narcotic analgesics. In the future, further studies on the evaluation of the empirical results of NIMS and review of systems in other countries will be required.

• Korean Journal of Clinical Pharmacy
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• v.9 no.1
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• pp.35-43
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• 1999

Over the last 50 years, a number of antibiotic agents have been developed and clinically used in the area of infectious diseases. Due to antimicrobial resistance problems and increasing health care costs, the rational use of antibiotics has been required. As a drug of choice to treat infections caused by MRSA, vancomycin has been extensively prescribed since the late 1970's. Recently, reports of vancomycin-resistant organisms such as VRE and VRSA have been increased to draw medical concerns. The objectives of this study were to evaluate the rational use of vancomycin and the appropriateness of the Restrictional Program of Antibiotic Utilization (RPAU) which has been operated at Samsung Medical Center. A retrospective chart review was performed in 132 hospitalized patients treated with vancomycin in the surgery departments from. January to June 1998. The guidelines of ASHP and HICPAC for vancomycin were modified and used as our criteria to determine the vancomycin DUE. In one hundred out of the patients, uses of vancomycin were approved by the Department of Infectious Diseases (DID) based on the RPAU. Vancomycin was appropriately used in $62.5\%$ of the 100 patients according to the criteria of justification of use, while $60.0\%,\;60.0\%,\;79.0\%,\;and\;51.0\%$ of the patients showed appropriate according to those of lab reports such as applicable culture obtained, pretreatment SCr, WBC and serum drug concentration monitoring, respectively. Although the rest 32 patients were not approved to receive vancomycin by the DID, twenty two percent continued receiving vancomycin treatment. This might result from the fact that the RPAU was started not before the use of antibiotics but in the middle of antimicrobial therapy. Continual education should be provide to the related health professionals and the RPAU should be simultaneously modified in order to increase the rate of appropriate uses of antibiotics.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.16-20
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• 2010

Thiosultap, a nereistoxin analog insecticide, registered in China has been used to control selected beetles and Lepidopteran pests on rice, vegetables and fruit trees. Although domestic use of thiosultap is not permitted, it is needed to monitor this insecticide from imported crops because that has been used on crops in many foreign countries, especially China. Thiosultap in hulled rice was determined as nereistoxin derived in basic condition by GC-FPD. This method accomplished ion-associated liquid-liquid partitioning for cleanup, and limit of quantification and linearity performed by the established method were 0.05 mg $kg^{-1}$ and 0.995$(r^2)$. The recoveries performed by control hulled rice fortified with thiosultap at 0.5 and 2.5 mg $kg^{-1}$ were $96.1{\pm}7.9\sim100.8{\pm}6.1%$.