• Toxicological Research
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• v.14 no.3
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• pp.315-320
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• 1998

In vitro skin iritation of anti-inflammatory drugs was investigated in terms of the cytotoxicity method to human skin fibroblast cells. Five anti-inflammatory drugs (Diclofenac, Naproxen, Meclofenamic acid, Ibuprofen and Fnoprofen) which are commercially available as oral preparations or injections were tested. The cytotoxicity of 5 chemicals was evaluated by using MTT[tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. NRU (neutral red uptake) assay and Alamar Blue assay after fibroblast cells had been exposed to the chemicals for 24 hours or 489 hours. The $IC_{50}$ values of the chemicals showed the comparative strength of cytotoxicity as following order of Meclofenamic acid>Diclofenac>Fenoprofen>Ibuprofen>Naproxen. The values of $IC_{50}$ determined by Alamar Blue assay were lower than those of MTT and NRU assay. These data suggest Alamar Blue assay can be useful method for assessing in vitro skin irritation potential of anti-inflammatory drugs.

• Toxicological Research
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• v.2 no.2
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• pp.103-111
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• 1986

• Polymer(Korea)
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• v.36 no.3
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• pp.332-337
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• 2012

The primary objective of this work is to find the properties of sustained release dissolution pattern depending on solubility of drugs, so venlafaxine HCl and carbamazepine tablets were made by using polymer wich various particle size. Hydroxy propyl methyl cellulose (HPMC) has been utilized in this study as an excipient that is one of the most widely used polymers for an oral sustained release formulation, and drug release pattern was strongly influenced by swelling rate depending on particle size of HPMC. Scanning electron microscope (SEM) was employed to investigate the surface of tablets with various HPMC particle size, and differential scanning calorimeter (DSC) was employed to investigate the crystallization of drugs in tablets. The release model equation was applied to analyze the main mechanism of drug release pattern. The results demonstrate that drug release pattern is controlled by the drug solubility and HPMC particle size.

• Safety and Health at Work
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• v.4 no.1
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• pp.1-11
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• 2013

This review surveys the recent literature on the neurodevelopmental impacts of chemical exposures during pregnancy. The review focuses primarily on chemicals of recent concern, including phthalates, bisphenol-A, polybrominated diphenyl ethers, and perfluorinated compounds, but also addresses chemicals with longer histories of investigation, including air pollutants, lead, methylmercury, manganese, arsenic, and organophosphate pesticides. For some chemicals of more recent concern, the available literature does not yet afford strong conclusions about neurodevelopment toxicity. In such cases, points of disagreement among studies are identified and suggestions provided for approaches to resolution of the inconsistencies, including greater standardization of methods for expressing exposure and assessing outcomes.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.217-217
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• 1994

Calcium entry blockers, capable of inhibiting transmembrane influx of extracellular calcium through specific calcium channels, are useful drugs in the treatment of angina pectoris, hypertension, cardiac arrythmia, and various cardiovascular disorders. Compounds having isoquinoline structures have recently been reported to possess calcium antagonistic action. Therefore, in the present study, we have attempted to synthesize some isoquinoline and related compound.; in order to search for potentially effective chemicals acting on cardiovascular system, and evaluated their pharmacological properties focusing on calcium antagonistic actions. Almost all of the compounds so far synthesized, had inhibitory action against phenylephrine or high potassium-induced contraction in vascular smooth muscle with different degrees of potencies depending on their structures, However, some of tetrahydroisoquinoline analogs showed directly inhibit calcium current in isolated rabbit cardiac myocytes examined by patch clamp techniques. The pharmacological properties of these compounds need more intensive investigation as to whether these chemicals may have developed as a new cardiovascular active drugs. Therefore, we are now under investigation of the mechanism of action of these compounds.

• Toxicological Research
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• v.31 no.2
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• pp.97-104
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• 2015

The skin exposure to solar irradiation and photoreactive xenobiotics may produce abnormal skin reaction, phototoxicity. Phototoxicity is an acute light-induced response, which occurs when photoreacive chemicals are activated by solar lights and transformed into products cytotoxic against the skin cells. Multifarious symptoms of phototoxicity are identified, skin irritation, erythema, pruritis, and edema that are similar to those of the exaggerated sunburn. Diverse organic chemicals, especially drugs, are known to induce phototoxicity, which is probably from the common possession of UV-absorbing benzene or heterocyclic rings in their molecular structures. Both UVB (290~320 nm) and UVA (320~400 nm) are responsible for the manifestation of phototoxicity. Absorption of photons and absorbed energy (hv) by photoactive chemicals results in molecular changes or generates reactive oxygen species and depending on the way how endogenous molecules are affected by phototoxicants, mechanisms of phototoxcity is categorized into two modes of action: Direct when unstable species from excited state directly react with the endogenous molecules, and indirect when endogeneous molecules react with secondary photoproducts. In order to identify phototoxic potential of a chemical, various test methods have been introduced. Focus is given to animal alternative test methods, i.e., in vitro, and in chemico assays as well as in vivo. 3T3 neutral red uptake assay, erythrocyte photohemolysis test, and phototoxicity test using human 3-dimensional (3D) epidermis model are examples of in vitro assays. In chemico methods evaluate the generation of reactive oxygen species or DNA strand break activity employing plasmid for chemicals, or drugs with phototoxic potential.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.233-243
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• 1999

Food safety or sanitation are terms broadly applicable to procedures designed to ensure that food quality is high and free of factors which may adversely affect human health. These factors include zoonotic diseases and acute and chronic effects of ingesting natural and human-made xenobiotics. Use of drugs in animal production for the treatment and control of animal diseases, to promote growth rate, and to improve feed conversion efficiency has expanded year by year, thus increasing the possibilities for occurrences in animal products of residues harmful to humans. Governmental agencies have made efforts to control or prevent residue problems. The Korean Food and Drug Administration (KFDA) is charged with the responsibility of establishing tolerances for veterinary drugs, pesticides, and mycotoxins and other non-pharmaceutical substances. The Department of Veterinary Service is responsible for establishing guidelines regarding withdrawal times of drugs, approval of drugs, their uses, and sanitation enforcement of livestock products. The authors describe the toxicological basis for the establishment of tolerance levels for xenobiotics and the pharmacokinetic basis for establishing withdrawal time for veterinary drugs. The regulatory tolerance levels of chemicals in pork and swine feed, Korean regulations on the use of feed additives, rapid residue test methods, the National Residue Program, and the Food Animal Residue Avoidance Databank are discussed. Rapid EIA methods that are under development for the screening of live animals are described These methods predict tissue residues from an examination of blood samples taken from pigs before they are slaughtered.

• Toxicological Research
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• v.18 no.3
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• pp.215-226
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• 2002

Acute or repeated physical exercise affects a large number of physiological parameters including hemodynamics, respiration, pH, temperature, gastrointestinal function and biotransformation, which determine the pharmacokinetics of drugs and chemicals. The rate and the amount of a chemical reaching the active site are altered by physical exercise, which results in significant changes in pharmacolosical/toxicological activity of the chemical. This aspect of physical exercise has vast implication in therapeutics and in safety evaluation, particularly for chemicals that have a low margin of safety. However there appears to be a wide inter- and intraindividual variation in the effects of physical exercise depend-ing on the duration, intensity and type of exercise, and also on the properties of each chemical. It is suggested that more studies need to be done to determine which factor(s) plays a major role in the disposition of chemicals in human/animals performing physical exercise. Certain chemicals induce severe toxicity due to metabolic conversion to reactive intermediate metabolites. it is suggested that repeated exercise may enhance the free radical scavenging system by increasing the activity of antioxidant enzymes. This area of research remain to be explored to elucidate the interaction of exercise and chemical on the antioxidant system.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.97-102
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• 2002

Life Science Research Center of SK Chemicals has developed a 3rd-generation anticancer platinum drug for the first time in the nation′s 100-year-old pharmaceutical industry. The Korea Food and Drug Administration (KFDA) approved the sale of "Sunpla" (code name SKI 2053R, general name : Heptaplatin) on July 14, 1999 for the treatment of advance, metastatic gastric cancer. Cisplatin, the 1 st-generation anticancer drug, which was developed by Bristol-Myers of the United States in 1976, is one of the most potent anticancer drugs and is a major component of combination chemotherapy for a variety of human cancers. However its clinical usefulness has frequently been limited not only by undesirable side effects such as severe renal toxicity, nausea, vomiting, ototoxicity, and neurotoxicity but also by the development of resistance. Carboplatin, the 2nd-generation anticancer platinum drug, which was also developed by Bristol-Myers in 1986, has modified the problems of the renal and gastrointestinal toxicities of cisplatin. Carboplatin, however, has no enhanced therapeutic efficacy over cisplatin and does not possess the property to overcome cross-resistance to cisplatin.

• Genomics & Informatics
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• v.17 no.2
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• pp.15.1-15.7
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• 2019

Automatically detecting mentions of pharmaceutical drugs and chemical substances is key for the subsequent extraction of relations of chemicals with other biomedical entities such as genes, proteins, diseases, adverse reactions or symptoms. The identification of drug mentions is also a prior step for complex event types such as drug dosage recognition, duration of medical treatments or drug repurposing. Formally, this task is known as named entity recognition (NER), meaning automatically identifying mentions of predefined entities of interest in running text. In the domain of medical texts, for chemical entity recognition (CER), techniques based on hand-crafted rules and graph-based models can provide adequate performance. In the recent years, the field of natural language processing has mainly pivoted to deep learning and state-of-the-art results for most tasks involving natural language are usually obtained with artificial neural networks. Competitive resources for drug name recognition in English medical texts are already available and heavily used, while for other languages such as Spanish these tools, although clearly needed were missing. In this work, we adapt an existing neural NER system, NeuroNER, to the particular domain of Spanish clinical case texts, and extend the neural network to be able to take into account additional features apart from the plain text. NeuroNER can be considered a competitive baseline system for Spanish drug and CER promoted by the Spanish national plan for the advancement of language technologies (Plan TL).