• Proceedings of the PSK Conference
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• 2000.10a
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• pp.234.2-234.2
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• 2000

• Journal of Haehwa Medicine
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• v.3 no.2
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• pp.315-321
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• 1995

An extensive anticancer drug screening from natural resources has been carried out primarily using murine tumor model for past fourty years. Recently a new screening program from NCI, so called disease-oriented screening system. has been estabished to detect anticancer drugs that show selective growth inhibition toward variety of tissue specific human solid tumors originated from leukemia, lung, colon, CNS, melanoma, ovarian, renal, prostate amd breast. To develope the anticancer drugs from oriental medicinal herbs, we investigated the cytotoxic effects against human tumor cell panels with 23 kinds of MeOH extract of medicinal herbs. Evodiae Fructus, Meliae Toosendan Fructus, Saussureae Radix and Pharbitidis Semen showed strong activities against several tumor cell lines.

• Proceedings of the Plant Resources Society of Korea Conference
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• 1993.08a
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• pp.14-20
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• 1993

We in anticancer drug development from natural resources have conceived and used a wide variety of experimental screening systems to support our efforts during the past 20 tears. Screens have been devided to address targets at the molecular, biochemical and cellular levels, both in vivo and in vitro. Screens have been essential for the experimental evaluation of the products from natural sources. In this congress, antitumor screening methods for deveol[ment of new drugs from natural sources and evaluation of their crude drugs are discussed.

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.155-155
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• 2001

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.11a
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• pp.150-150
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• 2004

• Mass Spectrometry Letters
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• v.13 no.4
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• pp.158-165
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• 2022

Many therapeutic class drugs such as beta-blocker, corticosteroids, NSAIDs, etc are prohibited substances in the horse racing industry. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology makes it possible to isolate drugs from interference, enables various drug analyses in complex biological samples due to its sensitive sensitivity, and has been successfully applied to doping control. In this paper, we describe a rapid and sensitive method based on solid-phase extraction (SPE) using solid phase cartridge and LC-MS/MS to screen for different class's 35 drug targets in equine plasma. Plasma samples were pretreated by SPE with the NEXUS cartridge consisted non-polar carbon resin and minimum buffer solvent. Chromatographic separation of the analytes was performed on ACQUITY HSS C18 column (2.1 × 150 mm, 1.8 ㎛). The elution gradient was conducted with 5 mM ammonium formate (pH 3.0) in distilled water and 0.1% formic acid in acetonitrile at a flow rate of 0.25 mL/min. The selected reaction monitoring (SRM) mode was used for drug screening with multiple transitions in the positive ionization mode. The specificity, limit of detection, recovery, and stability was evaluated for validation. The method was found to be sensitive and reproducible for drug screening. The method was applied to plasma sample analysis for the proficiency test from the Association of Racing Chemist.

• Journal of The Korean Society of Clinical Toxicology
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• v.19 no.1
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• pp.24-30
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• 2021

Purpose: In Korea, it is predicted that the proportion of drug abusers among patients visiting the emergency room will soon increase. Several emergency medical institutions in Korea are conducting field urine screening tests for poisoning. In this study, we investigated the characteristics and usefulness of urine toxicology screening tests. Methods: The medical records of patients with positive results for tetrahydrocannabinol and methamphetamine from urine toxicology screening tests at a tertiary university hospital from August 2016 to August 2019 were reviewed retrospectively. The subjects were classified into positive and false-positive groups, and their clinical characteristics were compared and analyzed. Results: Of the 2,026 patients surveyed, 823 patients (40.6%) tested positive for one or more drugs. Among them, 12 cases (0.6%) were positive for methamphetamine and 40 cases (2.0%) were positive for tetrahydrocannabinol. The positive and the false-positive rates for methamphetamine were 66.7% and 33.3%, respectively. The positive and the false-positive rates for tetrahydrocannabinol were 2.5% and 97.5%, respectively. Conclusion: Methamphetamine showed a relatively low false-positive rate in our study. Therefore, this test seemed to assist in diagnosing methamphetamine poisoning when considered together with the present illness and physical examination results. On the other hand, the high false-positive rate for tetrahydrocannabinol tests indicates that this test was unlikely to assist in diagnosing tetrahydrocannabinol poisoning. However, considering the growing trend of illegal drug abusers in Korea, it may still be useful as a diagnostic tool for identifying drug users.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2291-2295
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• 2016

Small molecule tyrosine kinase inhibitors targeting HER 2 receptors have emerged as an important therapeutic approach in inhibition of downstream proliferation and survival signals for the treatment of breast cancers. Recent drug discovery efforts have demonstrated that naturally occurring polyphenolic compounds like delphinidin have potential to inhibit proliferation and promote apoptosis of breast cancer cells by targeting HER2 receptors. While delphinidin may thus reduce tumour size, it is associated with serious side effects like dysphonia. Owing to the narrow therapeutic window of delphinidin, the present study aimed to identify high affinity compounds targeting HER2 with safer pharmacological profiles than delphinidin through virtual screening approaches. Delphinidin served as the query parent for identification of structurally similar compounds by Tanimoto-based similarity searching with a threshold of 95% against the PubChem database. The compounds retrieved were further subjected to Lipinski and Verber's filters to obtain drug like agents, then further filtered by diversity based screens with a cut off of 0.6. The compound with Pubchem ID: 91596862 was identified to have higher affinity than its parent. In addition it also proved to be non-toxic with a better ADMET profile and higher kinase activity. The compound identified in the study can be put to further in vitro drug testing to complement the present study.

• YAKHAK HOEJI
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• v.13 no.4
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• pp.147-148
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• 1969

As one of projects of this Institute, 330 species of plants which are currently used as herb drugs in Korea were screened for the presence of alkaloids, phenolic compounds, flavonoids, chalcones, lactones, glycosides, carbohydrates, terpenoids, steroids, proteins, polypeptides, saponins, and organic acids. The most reliable presence of alkaloids detected by thin layer chromatography is presented by screening of 52 species.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.41-49
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• 1994

The most common conventional method of discovering a drug involves a massive screening of a large number of compounds in chemical libraries or in the extracts from natural sources such as plants or microbial broths followed by chemical modification of one or more active compounds to improve their properties as a drug. When the three-dimensional structure of the target molecule for which the drug is searched is known the drug discovery process can be significantly simplified, This is especially true when the three-dimensional structure of a complex between the target and a lead compound is known. In this lecture our experience on the structure-based drug design for human CDK2(cyclin-dependent protein kinase 2) will be discussed with special emphasis on the strength and weakness of this approach of drug discovery. The regulation of the activity of CDK2 plays an important role in the cell proliferation of normal and cancer cells.