• 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.

• Korean Journal of Pharmacognosy
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• v.3 no.4
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• pp.199-204
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• 1972

A new physico-chemical method for identifying botanical drugs was investigated. Fifty drugs were chosen from the presently exported botanical drugs and were classified into 12 groups chemotaxonomically. Various extract(either, 50% ethanol and water) of each group were developed with same solvent system by using chromatographic method(TLC) and observed a characteristic pattern of each drugs. This method, therefore, can be applicable to identify each botanical drug out of the combined phyto-preparations.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.11a
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• pp.47-50
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• 1997

Drug development began with the finding of biologically active compounds which are obtained by chemical synthesis or from natural sources. The advent of Combinatorial Chemistry is recognized as a strategy which has a potential to change the methodology of research and development(R&D) of new drugs. Drug development has been carried out with diverse strategies. In the past several decades a variety of new methodology have been introduced in R&D. Random screening of accumulated synthetic samples which had been synthesized for development of other drugs led to the discovery of new drugs. The typical examples are anti-asthma drug trimethoquinol and calcium antagonist diltiazem. (herbesser). In particular the latter drug has been used as a calcium antagonist worldwide, however it was first synthesized to find new tranquilizer and this is the reason why diltiazem has benzodiazepam skeleton. The random screening contributed in the finding of new drugs were carried out with whole animal test and it is a standard methodology in R&D of new drugs. Aspirin is the first synthetic non-steroidal antiinflammatory drug(NSAID) and has been used for more than one hundred years. It is the first example of drug developed from natural product. Salicin is the main constituent of willow bark which had been used in Europe for a long time to treat arthritis and aspirin was developed from salicin. Most of NSAID used clinically were developed from the structure of aspirin, however it took 70 years to clarify why aspirin exhibits its antiinflammatory, analgesic and antipyretic activities. The target of aspirin is cyclooxygenase(COX)which is the first enzyme involved in arachidonate cascade leading to the production of prostaglandins(PG) and thromboxan(TX). Side effect of aspirin causing ulcer in stomach is rather serious problem, since aspirin is so popular drug easily obtained in drug store(OTP). This problem is now going to be solved by a new finding on COX, which have two different types, one is constitutionally expressed COX 1 in almost all organs and the other is inducible COX 2. COX 2 is the responsible enzyme in inflammation etc and now the search of COX 2 specific inhibitors is the target of R&D of next generation NSAID.

• Journal of Pharmaceutical Investigation
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• v.39 no.4
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• pp.299-307
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• 2009

Data exclusivity is one of the most important intellectual property rights of pharmaceuticals. During data exclusivity period, third parties are prohibited from relying on the data which the original company has submitted to regulatory authority for drug application. I investigated data exclusivity systems for pharmaceuticals in the US, EU, Canada and Korea. New chemical entities were usually given the longest periods of data exclusivity compared to drugs with new indication or new formulation, although the protection periods varied by country. For new drugs to be entitled to a data exclusivity, strict conditions should be met. Data exclusivity has also been provided as an incentive to promote clinical investigation and drug development for pediatric population or orphan diseases. In Korea, data exclusivity was adopted in 1995 as an additive provision to "drug re-examination" which is to investigate post-marketing safety information of new drugs. It was introduced with few discussion on the purposes or effects of data exclusivity on pharmaceutical industry and pharmaceutical market in this country. I found that Korea's data exclusivity system falls short of considerations on valuing innovation of pharmaceutical research. It is necessary to improve data exclusivity system in order to promote innovative pharmaceutical development and to balance intellectual property rights protection and access to drugs in this country.

• Korean Journal of Veterinary Pathology
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• v.1 no.2
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• pp.91-96
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• 1997

General steps in the discovery and development of novel drugs in the United States are presented. The first step is the discovery of novel drugs. Brief histories and mechanisms of a few novel drugs in the American market are outlined. In this presentation preclinical animal toxicologic studies (drug safety evaluateion) are emphasized in regard to drug development. When preclinical animal studies have defined the toxicity and the doses at which it occurs an Investigational new Drug Application (IND) is submitted to the Food and Drug Administration (FDA) An IND notifies the FDA the intention to begin testing a novel drug in human subjects.

• YAKHAK HOEJI
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• v.56 no.1
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• pp.66-69
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• 2012

This study aims to assess the aggregate contribution of new drugs to the increase in life expectancy. We constructed a panel data combining mortality data in KOSIS and a drug dataset generated by assigning new drugs listed in 2000~2009 to their respective ICD codes. We found that 10% increase in stock of new drug led to 0.13~0.27% increase in the probability of survival to age 65. Due to lack of disease-specific life table, we used indirect approach to estimate the effect of new drugs on longevity. Using ordinary least squares, the estimate of the probability of survival to age 65 (logarithm) on life expectancy for all ages was 24.92. In conclusion, the increase in life expectancy of the entire population in Korea between 2000 and 2009 resulting from NMEs is 1.95 years, which explains 46.6% of real increase in life expectancy.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.3
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• pp.137-143
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• 2006

The market for anti-inflammatory drugs is large and is expanding rapidly as populations age. Key to the development of new drugs are novel chemotypes. Marine organisms harbour a diverse range of unique compounds with applications in a multitude of disease indications. This review looks at anti-inflammatory compounds isolated from New Zealand marine organisms.

• Natural Product Sciences
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• v.21 no.4
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• pp.227-230
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• 2015

Chemical investigation of the fermentation broth of a Soft Coral-Derived fungus Pestalotiopsis sp., led to the isolation of a new phthalide derivative, pestalotiolide A (1), three known analogues (2, 3 and 4), along with 5'-O-acetyl uridine (5) first isolated as a natural product. The structure of the new compound (1) was established by comprehensive spectroscopic analysis and chemical methods. Compounds 1 - 4 possessed varying degrees of antiviral activities, which was reported for the first time. Compared to the positive control ribavirin ($IC_{50}=418.0{\mu}M$), pestalotiolide A (1) exhibited significant anti-EV71 activity in vitro, with an $IC_{50}$ value of $27.7{\mu}M$. Furthermore, the preliminary structure-activity relationship of antiviral activities was also discussed.

• Korean Journal of Biological Psychiatry
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• v.5 no.2
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• pp.175-183
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• 1998

To consider current concepts of epilepsy further, the brief review begins with a discussion of what is epilepsy, discribes multifactorial nature of epileptic disorders, and ends with a presentation of current classifications. A combination of the standard antiepielptic drugs(AEDs) may be necessary to treat intractable seizures, but no studies have been done to indicate an optimal combination. The new AEDs provide alternative choices, but questions remain about the optimal timing and manner of administration. AEDs selection must individualized, no drug of choice can be named for all patients.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5715-5719
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• 2014

Autophagy is crucial in the maintenance of homeostasis and regenerated energy of mammalian cells. Macroautophagy and chaperone-mediated autophagy(CMA) are the two best-identified pathways. Recent research has found that in normal cells, decline of macroautophagy is appropriately parallel with activation of CMA. However, whether it is also true in cancer cells has been poorly studied. Here we focused on cross-talk and conversion between macroautophagy and CMA in cultured Burkitt lymphoma Raji cells when facing serum deprivation and exposure to a toxic compound, arsenic trioxide. The results showed that both macroautophagy and CMA were activated sequentially instead of simultaneously in starvation-induced Raji cells, and macroautophagy was quickly activated and peaked during the first hours of nutrition deprivation, and then gradually decreased to near baseline. With nutrient deprivation persisted, CMA progressively increased along with the decline of macroautophagy. On the other hand, in arsenic trioxide-treated Raji cells, macroautophagy activity was also significantly increased, but CMA activity was not rapidly enhanced until macroautophagy was inhibited by 3-methyladenine, an inhibitor. Together, we conclude that cancer cells exhibit differential responses to diverse stressor-induced damage by autophagy. The sequential switch of the first-aider macroautophagy to the homeostasis-stabilizer CMA, whether active or passive, might be conducive to the adaption of cancer cells to miscellaneous intracellular or extracellular stressors. These findings must be helpful to understand the characteristics, compensatory mechanisms and answer modes of different autophagic pathways in cancer cells, which might be very important and promising to the development of potential targeting interventions for cancer therapies via regulation of autophagic pathways.