• BMB Reports
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• v.36 no.3
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• pp.305-311
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• 2003

A modified actinomycin D was prepared with a hydroxyl group that replaced the amino group at the chromophore 2-position, a substitution known to strongly reduce affinity for double-stranded DNA. Interactions of the modified drug on single-stranded DNAs of the defined sequence were investigated. Competition assays showed that 2-hydroxyactinomycin D has low affinity for two oligonucleotides that have high affinities ($K_a\;=\;5-10{\times}10^6\;M^{-1}$ oligomer) for 7-aminoactinomycin D and actinomycin D. Primer extension inhibition assays performed on several single-stranded DNA templates totaling around 1000 nt in length detected a single high affinity site for 2-hydroxyactinomycin D, while many high affinity binding sites of unmodified actinomycin D were found on the same templates. The sequence selectivity of 2-hydroxyactinomycin D binding is unusually high and approximates the selectivity of restriction endonucleases. Binding appears to require a complex structure, including residues well removed from the polymerase pause site.

• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.461-470
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• 2017

Anticoagulant drugs, like vitamin K antagonists and heparin, have been the mainstay for the treatment and prevention of venous thromboembolic disease for many years. Although effective if appropriately used, traditional anticoagulants have several limitations such as unpredictable pharmacologic and pharmacokinetic responses and various adverse effects including serious bleeding complications. New oral anticoagulants have recently emerged as an alternative because of their rapid onset/offset of action, predictable linear dose-response relationships and fewer drug interactions. However, they are still associated with problems such as bleeding, lack of reversal agents and standard laboratory monitoring. In an attempt to overcome these drawbacks, key steps of the hemostatic pathway are investigated as targets for anticoagulation. Here we reviewed the traditional and new anticoagulants with respect to their targets in the coagulation cascade, along with their therapeutic advantages and disadvantages. In addition, investigational anticoagulant drugs currently in the development stages were introduced.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.9.2-9.2
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• 2011

Ultrathin polyelectrolyte (PE) multilayer films prepared by the versatile layer-by layer (LbL) assembly method have been utilized for the preparation of light-emitting diodes, electrochromic, membrane, and drug delivery system, as well as for selective area patterning and particle surface modification because the various materials with specific properties can be inserted into the film with nano-level thickness irrespective of the size or the shape of substrate. Since the introduction of the LbL technique in 1991 by Decher and Hong, various hydrophilic materials can be inserted within LbL films through complementary interactions (i.e., electrostatic, hydrogen-bonding or covalent interaction). In this study, it is demonstrated that LbL SA multilayer films based on nucleophilic substitution reaction can allow the preparation of the highly efficient magnetic and/or optical films and nonvolatile memory devices.

• Advances in Traditional Medicine
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• v.2 no.2
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• pp.80-86
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• 2002

Ginseng is a perennial herb widely used in China, Japan, and Korea. It is also one of the most commonly used herbal medicines in the U.S. Although it is generally considered safe to use, adverse effects associated with ginseng use have been reported. Inappropriate ginseng use, such as high dose administration, may cause insomnia, headaches, diarrhea, as well as cardiovascular and endocrine disorders. Other factors that may contribute to adverse effects of ginseng include the variety of ginseng species, variability in commercial ginseng preparations, and potential ginseng-drug interactions. To minimize adverse effects of ginseng, consumers should be advised to use it appropriately, and the herbal industry should try to provide standardized ginseng preparations.

• Korean Journal of Clinical Pharmacy
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• v.26 no.4
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• pp.269-282
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• 2016

Venous thromboembolism, encompassing deep vein thrombosis and pulmonary embolism, has increased in cancer patients and adversely affects their prognosis. Low-molecular-weight heparins are recommended as efficacious and safe anticoagulation treatment in cancer patients. However, in practice, oral anticoagulation is preferred, especially if longterm or extended treatment is necessary. Novel oral anticoagulants have recently emerged as an alternative to the standard therapy owing to the ease of administration, predictable anticoagulation effect without the need of laboratory monitoring, and fewer drug interactions. These new agents have been shown as effective and safe for the management of cancer-associated thrombosis in ongoing head-to-head comparative trials. Here we review the advances and limitation of current anticoagulant therapies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.518-524
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• 1998

Liposomes have been widely employed as biomembrane-mimetic system and drug-delivery system. In these applications, the low stability of liposomes has been the most serious problem. They have relatively short half-lives and easily lysed through interactions with biological components. This study was performed to investigate the effects of godulbaegi extracts on the fludity of phospholipid liposomes. We used dipalmitoyl phosphatidylcholine(DPPC) liposomes which make most stable liposomes among the other phosphatidylcholines. The thermograms of the DPPC liposomal bilayers incorporated with the hexane extract of godulbaegi(Ixeris sonchifolia H.) were obtained, and the enthalpy changes and the sizes of cooperative unit of the transition were calculated. The incorporation of the Ixeris sonchifolia H. into the liposomal bilayers effectively reduced the transition temperature at which the transition from gel state to liquid-crystalline state occurs, broadened the thermogram peaks, and reduced the ratio of van't Hoff to calorimetric enthalpies. These results indicate indicate that the godulbaegi extracts (Ixeris sonchifolia H.) have significant effects on the fluidity of biological membrance.

• Korean Journal of Biological Psychiatry
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• v.18 no.2
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• pp.61-71
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• 2011

Substance addiction is a chronically relapsing disorder that has been characterized by a vicious cycle composed of intoxication, craving/anticipation, withdrawal, and response inhibition/bingeing. Here we summarize the findings from neuroimaging studies in addiction according to these behavioral components and suggest the integrated neurobiological model of drug addiction and related brain correlates. The roles of various prefrontal regions, thalamus, memory circuit, anterior cingulated, and insula were also suggested in addition to those of classical mesolimbic dopaminergic system and its responsivity. Limited studies of behavioral addiction demonstrated a similarity with substance addiction on the neurobiological basis. Based on the current understanding of neurobiology of addiction, further researches on interactions of behavioral components and their brain correlates, behavioral addiction, and therapeutic applications will be desired.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.5005-5006
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• 2015

Gastric cancer as one of the most common cancers worldwide has various genetic and environmental risk factors including Helicobacter pylori (H.pylori) infection. Recently, loss of a tumor suppressor gene named promyelocytic leukemia (PML) has been identified in gastric cancer. However, no mutation has been found in this gene in gastric cancer samples. Cag A H.pylori protein has been shown to exert post transcriptional regulation of some tumor suppressor genes. In order to assess such a mechanism for PML degradation, we performed in silico analyses to establish any interaction between PML and Cag A proteins. In silico interaction and docking studies showed that these two proteins may have stable interactions. In addition, we showed that imatinib kinase inhibitor can restore PML function by inhibition of casein kinase 2.

• 대한임상약리학회:학술대회논문집
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• 2004.12a
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• pp.10-10
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• 2004

• YAKHAK HOEJI
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• v.45 no.6
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• pp.664-669
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• 2001

Acebutolol is almost absorbed after oral administration, but its bioavailability is reduced because of considerable first-pass metabolism through the gastrointestinal tract and liver. The purpose of this study was to report the pharmacokinetic changes of acebutolol (15 mg/kg,oral) and its main metabolite, diacetolol in rabbits pretreated (15 mg/kg, oral) and coadministered (15 mg/kg, S. C., bid for 3 days) with diltiazem. The plasma concentration and area under the plasma concentration-time curves (AUC) of acebutolol and diacetolol were significantly increased in rabbits pretreated and coadministered with diltazem. The elimination rate constant ( $K_{el}$ ) and total body clearances (CL $_{t}$) of acebutolol and diacetolol were significantly decreased and half-life of those were significantly prolonged in the rabbit. Metabolite percentage rate of diacetolol to the plasma concentration of total acebutolol in rabbits pretreated and coadministered with diltiazem were significantly decreased. The results suggest that the dosage of acebutolol should be adjusted when the drug would be administered chronically with diltiazem in a clinical situation.n.