• 약학회지
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• 제48권2호
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• pp.105-110
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• 2004

Akt (or Protein Kinase B; PKB) is a serine/threonine kinase and is activated by phosphoinositide 3-kinase (PI3K) pathway. Recent evidence indicates that the abnormal activities or expression of Akt is closely associated with cancer, diabetes and neuro-degenerative diseases. These findings mean that Akt is likely to be a new therapeutic target for the treatment of disease. Here, we screened the effects of dithiolo-dithione derivatives such as SWU-20004, SWU-20009 and SWU-20025 on Akt activities. Among these compounds, only SWU-20009 (2-Thioxo-[1,3]dithiolo[4,5- $\beta$][1,4]dithiine-5,6-dicarboxylic acid dimethyl ester) inhibited the growth of KATOIII cell at micromolar range of concentration. Further investigation also revealed that SWU-20009 inhibited cellular Akt activity and induced apoptotic cell death.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.95-95
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• 2002

Cyclooxygenases (COXs) are key enzymes in the conversion of arachidonic acid into prostanoids, which are involved in cell proliferation and inflammation. Two distinct COXS have been identified: COX-l which is constitutively expressed and COX-2 which is induced by different products such as tumor promoters or growth factors.(omitted)

• 한국세라믹학회지
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• 제23권1호
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• pp.7-12
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• 1986

Dielectric properties of $Ba_{0.9}Ca_{0.1}(Ti_{1-x}Sn_x)O_3$ were investigated from x=0 to 0.20, and temperature range -4$0^{\circ}C$~13$0^{\circ}C$ Density and grain size decreased with increasing Sn content due to grain growth inhibitor. Dielectric constant below the Curie temperature increased with increasing Sn content and dissipation factor dec reased. These results are due to grain size effect and internal stress. Curie temperature was shifted to lower temperature with increasing ratio of total polarizability to volume resulting from substitution of $Ba^{2+}$ ion with $Ca^{2+}$ ion $Ti^{4+}$ ion with $Sn^{4+}$ ion.

• Asian-Australasian Journal of Animal Sciences
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• 제29권11호
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• pp.1523-1529
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• 2016

Soybean meal (SBM), a commonly used protein source for animal feed, contains anti-nutritional factors such as trypsin inhibitor, phytate, oligosaccharides among others, which limit its utilization. Microbial fermentation using bacteria or fungi has the capability to improve nutritional value of SBM by altering the native composition. Both submerged and solid state fermentation processes can be used for this purpose. Bacterial and fungal fermentations result in degradation of various anti-nutritional factors, an increase in amount of small-sized peptides and improved content of both essential and non-essential amino acids. However, the resulting fermented products vary in levels of nutritional components as the two species used for fermentation differ in their metabolic activities. Compared to SBM, feeding non-ruminants with fermented SBM has several beneficial effects including increased average daily gain, improved growth performance, better protein digestibility, decreased immunological reactivity and undesirable morphological changes like absence of granulated pinocytotic vacuoles.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2819-2822
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• 2013

In this study, antiproliferative effects of the selective estrogen receptor modulator Tamoxifen and the aromatase inhibitor letrozole (Femara) were evaluated and compared using the FM3A cell line, originating from a C3H mouse mammary carcinoma and positive in terms of estrogen receptor (ER) expression. Cell kinetic parameters including labelling index, mitotic index and labelling index were assessed after exposure of the. FM3A cell line to $0.001{\mu}g/ml$ of Tamoxifen and $0.25{\mu}g/ml$ of Femara for 4, 8, 16 and 32 h for all parameters. The results showed that cell growth was inhibited by both agents. There was a significant decrease in labelling index and mitotic index and significant increase in apoptotic index for all experimental groups. The differences between control and all experimental groups were statistically significant (p<0.001) for all applications.

• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.829-833
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• 2002

Angiogenesis is an essential event in a variety of physiological and pathological processes. Therefore, effective inhibition of this event is a promising strategy for treating angiogenesis-related diseases, including cancer. The current study investigated two unique bafilomycin-type macrolide inhibitors of angiogenesls, PC-766B' (1) and PC-766B (2). The strain RK97-56 which produced the inhibitors was identified as Nocardia sp. by chemotaxonomic analyses, and the purification of the inhibitors was guided by their anti-angiogenic activities. PC-766B' (1) and PC-766B (2) exhibited potent inhibitory activities towards endothelial cell migration stimulated by the vascular endothelial growth factor (VEGF).

• Biomolecules & Therapeutics
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• 제16권1호
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• pp.1-8
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• 2008

Mitochondria are important sensor of apoptosis. $H_2O_2-induced$ cell death rate was enhanced by serum deprivation. In this study, we investigated whether serum deprivation using 0.5 or 3 % FBS induces apoptotic cell death through mitochondrial enzyme activation as compared to 10 % FBS. Apoptotic cell death was observed by chromosome condensation and the increase of sub-G0/G1 population. Serum deprivation reduced cell growth rate, which was confirmed by the decrease of S-phase population in cell cycle. Serum deprivation significantly increased caspase-9 activity and cytochrome c release from mitochondria into cytosol. Serum deprivation-induced mitochondrial changes were also indicated by the increase of ROS production and the activation of mitochondrial enzyme, succinate dehydrogenase. Mitochondrial enzyme activity increased by serum deprivation was reduced by the treatment with rotenone, mitochondrial electron transport inhibitor. In conclusion, serum deprivation induced mitochondrial apoptotic cell death through the elevation of mitochondrial changes such as ROS production, cytochrome c release and caspase-9 activation. It suggests that drug sensitivity could be enhanced by the increase of mitochondrial enzyme activity in serum-deprived condition.

• Biomolecules & Therapeutics
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• 제22권1호
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• pp.1-9
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• 2014

Vascular endothelial growth factor (VEGF)-VEGF receptor (VEGFR) system has been shown to play central roles not only in physiological angiogenesis, but also in pathological angiogenesis in diseases such as cancer. Based on these findings, a variety of anti-angiogenic drugs, including anti-VEGF antibodies and VEGFR/multi-receptor kinase inhibitors have been developed and approved for the clinical use. While the clinical efficacy of these drugs has been clearly demonstrated in cancer patients, they have not been shown to be effective in curing cancer, suggesting that further improvement in their design is necessary. Abnormal expression of an endogenous VEGF-inhibitor sFlt-1 has been shown to be involved in a variety of diseases, such as preeclampsia and aged macular degeneration. In addition, various factors modulating angiogenic processes have been recently isolated. Given this complexity then, extensive studies on the interrelationship between VEGF signals and other angiogenesis-regulatory systems will be important for developing future strategies to suppress diseases with an angiogenic component.

• Natural Product Sciences
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• 제21권4호
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• pp.255-260
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• 2015

Two new thiodiketopiperazines (TDKPs), designated graphiumins I (1) and J (2), were isolated from the culture broth of the marine-derived fungus Graphium sp. OPMF00224 by solvent extraction, silica gel column chromatography, and HPLC. Their absolute structures were elucidated by spectroscopic analyses (1D and 2D NMR data, ROESY correlations, and CD data) and chemical methods. They were found to be structurally rare TDKPs with a phenylalanine-derived indolin substructure. Compounds 1 and 2 inhibited yellow pigment production by methicillin-resistant Staphylococcus aureus (MRSA) with $IC_{50}$ values of 63.5 and $76.5{\mu}g/ml$, respectively, without inhibiting its growth, even at $250{\mu}g/ml$.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.150-150
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• 2001

$\beta$ -lapachone, the product of a tree (Tabebuia avellanedae) from South America, is known to exhibit various pharmacologic properties, the mechanisms of which are poorly understood. The aim of the present study was to further elucidate the possible mechanisms by which $\beta$-lapachone exerts its anti-proliferative action in cultured human prostate cancer cells.(omitted)