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Drug Interaction in New Antipsychotics (새로운 항정신병약물의 약물상호작용)

Kim, Yong Sik;Kang, Ung Gu;Roh, Myoung Sun
- Korean Journal of Biological Psychiatry
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- v.7 no.1
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- pp.14-20
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- 2000
Recently atypical antipsychotics have been used as first line agent in the treatment of schizophrenia, and also played a significant role in the treatment of many kinds of psychiatric disorders. The pharmacokinetic and pharmacodynamic properties of these newer antipsychotics are well known through preclinical and early clinical trials. However, it is important to note the limitations of the results due to its relatively short experience. Clozapine is eliminated principally by the hepatic P450 1A2 and 3A4 cytochrome enzymes. 1A2 inducers such as carbamazepine and smoking can reduce its half-life, while 1A2 inhibitors such as SSRIs, especially fluvoxamine can increase its duration of action. Carbamazepine should be avoided in a patient on clozapine because of carbamazepine's potential effects on bone marrow. Benzodiazepines tend to increase the chances of sedation, delirium and respiratory depression. Risperidone is metabolized to 9-hydroxyriperidone by the hepatic P450 2D6 cytochrome enzymes. Fluoxetine and paroxetine, 2D6 inhibitors interfere with metabolism, but 9-hydroxyrisperidone has similar biological activity as parental drug, so it has little affect on the outcome. Olanzapine shows minimal capacity to inhibit cytochrome P450 isoenzymes and shows minimal chance of drug interaction. It is eliminated principally by the hepatic P450 1A2 and 2D6 cytochrome enzymes.
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Physicochemical Characterization and Carcinoma Cell Interaction of Self-Organized Nanogels Prepared from Polysaccharide/Biotin Conjugates for Development of Anticancer Drug Carrier

Park Keun-Hong;Kang Dong-Min;Na Kun
- Journal of Microbiology and Biotechnology
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- v.16 no.9
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- pp.1369-1376
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- 2006
Self-organized nanogels were prepared from pullulan/biotin conjugates (PU/Bio) for the development of an effective anticancer drug delivery system. The degree of biotin substitution was 11, 19, and 24 biotin groups per 100 anhydroglucose units of pullulan. The physicochemical properties of the nanogels (PU/Bio1, 2 and 3) in aqueous media were characterized by dynamic light scattering, transmission electron microscopy, and fluorescence spectroscopy. The mean diameter of all the samples was less than 300 nm with a unimodal size distribution. The critical aggregation concentrations (CACs) of the nanoparticles in distilled water were $2.8{\times}10^{-2},\;1.6{\times}10^{-2}$, and $0.7{\times}10^{-2}mg/ml$ for the PU/Bio1, 2, and 3, respectively. The aggregation behavior of the nanogels indicated that biotin can perform as a hydrophobic moiety. To observe the specific interaction with a hepatic carcinoma cell line (HepG2), the conjugates were labeled with rhodamine B isothiocyanate (RITC) and their intensities measured using a fluorescence microplate reader. The HepG2 cells treated with the fluorescence-labeled PU/Bio nanoparticles were strongly luminated compared with the control (pullulan). Confocal laser microscopy also confirmed internalization of the PU/Bio nanogels into the cancer cells. Such results demonstrated that the biotin in the conjugate acted as both a hydrophobic moiety for self-assembly and a tumor-targeting moiety for specific interaction with tumor cells. Consequently, PU/Bio nanogels would appear to be a useful drug carrier for the treatment of liver cancer.
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Small Molecules Targeting for ESX-Sur2 Proteins' Interaction

Kwon, Young-Joo
- Proceedings of the Korean Society of Applied Pharmacology
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- 2008.04a
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- pp.77-86
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- 2008
It's been known that overexpression of the oncoprotein Her2 (eu/ErbB2), transmembrane receptor protein, occurs in human breast cancer. Her2-positive breast cancer patients who have Her2 overexpression show less therapeutic efficacy with enhanced metathesis and increased resistance to chemotherapy. So far, a humanized monoclonal antibody against Her2 protein called Herceptin is the only drug approved by Food and Drug Administration for treatment of Her2-overexpressing breast tumors. However, antibody therapy of Herceptin may not be ideal method for therapeutic intervention of Her2 protein expression. The therapeutic intervention of Her2 protein expression may be more efficiently achieved by inhibiting the expression of Her2 gene rather than by down-regulating the Her2 protein already overexpressed. Here, we found that the interaction of two proteins of ESX (an epithelial-restricted transcription factor) and DRIP130/CRSP130/Sur2 (a Ras-linked subunit of human mediator complexes) mediates the expression of Her2 gene. The association of ESX with Sur2 is mediated by a small hydrophobic face of 8-amino acid helix in ESX, suggesting that the ESX-Sur2 interaction can be a new novel target for Her2-positive cancer. The process to develop potent ESX-Sur2 interaction inhibitors targeting for Her2-positive cancer therapeutics will be discussed.
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