• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6075-6080
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• 2014

Lung cancer is the leading cause of cancer-related death worldwide. Here we investigated the antitumor effect and mechanism of Zhejiang (Huzhou and Jiande) saffron against lung cancer cell lines, A549 and H446. Using high performance liquid chromatography (HPLC), the contents of crocin I and II were determined. In vitro, MTT assay and annexin-V FITC/PI staining showed cell proliferation activity and apoptosis to be changed in a dose- and time-dependent manner. The inhibition effect of Jiande saffron was the strongest. In vivo, when mice were orally administered saffron extracts at dose of 100mg/kg/d for 28 days, xenograft tumor size was reduced, and ELISA and Western blotting analysis of caspase-3, -8 and -9 exhibited stronger expression and activity than in the control. In summary, saffron from Zhejiang has significant antitumor effects in vitro and in vivo through caspase-8-caspase-9-caspase-3 mediated cell apoptosis. It thus appears to have more potential as a therapeutic agent.

• Biomedical Science Letters
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• v.11 no.4
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• pp.441-446
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• 2005

The molecular mechanism of ischemia/reperfusion injury remains unclear. Reactive oxygen species (ROS) are implicated in cell death caused by ischemia/reperfusion in vivo or hypoxia in vitro. Poly (ADP-ribose) polymerase (PARP) activation has been reported to be involved in hydrogen peroxide-induced cell death in renal epithelial cells. This study was therefore undertaken to evaluate the role of P ARP activation in chemical hypoxia in opossum kidney (OK) cells. Chemical hypoxia was induced by incubating cells with antimycin A, an inhibitor of mitochondrial electron transport. Exposure of OK cells to chemical hypoxia resulted in a time-dependent cell death. In OK cells subjected to chemical hypoxia, the generation of ROS was increased, and this increase was prevented by the $H_2O_2$ scavenger catalase. Chemical hypoxia increased P ARP activity and chemical hypoxia-induced cell death was prevented by the inhibitor of PARP activation 3-aminobenzamide. Catalase prevented OK cell death induced by chemical hypoxia. $H_2O_2$ caused PARP activation and $H_2O_2-induced$ cell death was prevented by 3-aminobenzamide. Taken together, these results indicate that chemical hypoxia-induced cell injury is mediated by PARP activation through H202 generation in renal epithelial cells.

• KSBB Journal
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• v.8 no.5
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• pp.446-451
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• 1993

In ethanol fermentation, by-products such as glycerol, acetic acid and lactic acid are produced along with ethanol. The effects of culture conditions on cell growth ethanol production and by-products biosynthesis were investigated in ethanol fermentation using S. cerevisiae. With increasing aeration rate or yeast extract concentration, ethanol and by-products biosynthesis decreased while final cell mass increased. With increasing glucose concentration or decreasing temperature, final cell mass, ethanol and by-products concentrations all increased. The optimal pH for the cell growth, ethanol and by-products productions was found to be pH 4.5. By-products biosynthesis was found, in general, to proceed with the ethanol biosynthesis. The results can be applied for the optimization of ethanol fermentation and for the recovery and purification of ethanol from the culture broth.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.6
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• pp.439-446
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• 2022

The antitumoral effects of valdecoxib (Val), an United States Food and Drug Administration-approved anti-inflammatory drug that was withdrawn due to the side effects of increased risk of cardiovascular adverse events, were investigated in hypopharyngeal squamous cell carcinoma cells by performing a cell viability assay, transwell assay, immunofluorescence imaging, and Western blotting. Val markedly inhibited cell viability with an IC50 of 67.3 µM after 48 h of treatment, and also downregulated cell cycle proteins such as Cdks and their regulatory cyclin units. Cell migration and invasion were severely suppressed by inhibiting integrin α4/FAK expression. In addition, Val activated the cell cycle checkpoint CHK2 in response to excessive DNA damage, which led to the activation of caspase-3/9 and induced caspase-dependent apoptosis. Furthermore, the signaling cascades of the PI3K/AKT/mTOR and mitogen-activated protein kinase pathways were significantly inhibited by Val treatment. Taken together, our results indicate that Val can be used for the treatment of hypopharyngeal squamous cell carcinoma.

• Journal of Microbiology
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• v.44 no.4
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• pp.439-446
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• 2006

In this study, the growth kinetics of Lactobacillus rhamnosus and lactic acid production in continuous culture were assessed at a range of dilution rates $(0.05 h^{-1}\;to\;0.40h^{-1})$ using a 2L stirred tank fermenter with a working volume of 600ml. Unstructured models, predicated on the Monod and Luedeking-Piret equations, were employed to simulate the growth of the bacterium, glucose consumption, and lactic acid production at different dilution rates in continuous cultures. The maximum specific growth rate of L. rhamnosus, ${\mu}_{max}$, was estimated at $0.40h^{-1}$I, and the Monod cell growth saturation constant, Ks, at approximately 0.25g/L. Maximum cell viability $(1.3{\times}10^{10}CFU/ml)$ was achieved in the dilution rate range of $D=0.28h^{-1}\;to\;0.35h^{-1}$. Both maximum viable cell yield and productivity were achieved at $D=0.35h^{-1}$. The continuous cultivation of L. rhamnosus at $D=0.35h^{-1}$ resulted in substantial improvements in cell productivity, of 267% (viable cell count) that achieved via batch cultivation.

• Journal of the Korean Wood Science and Technology
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• v.41 no.5
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• pp.440-446
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• 2013

To understand transition characteristics from wood to charcoal, Quercus variabilis wood was carbonized at 200, 250, 300, 340, 540 and $740^{\circ}C$, respectively. Heating value, pH and surface property by FT-IR spectroscopy of the carbonized charcoal were investigated. Heating value and pH increased with increasing carbonization temperature from 4500 cal/g and 4.3 of the control wood to 8,000 cal/g and 9 of the charcoal carbonized at $740^{\circ}C$, respectively. From FT-IR spectroscopy, the peaks from O-H, C-H and C-O stretching disappeared during carbonization at 540 and $740^{\circ}C$. Aromatic skeletal vibration at near $1,506{\sim}1,593cm^{-1}$ was repidly increased until $540^{\circ}C$. These results suggest that the chemical and physical characteristics of wood components in cell wall can be easily changed by increasing carbonization temperature and the carbonization seem to be incomplete at temperature below $540^{\circ}C$.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.5
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• pp.446-456
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• 2005

Nerve growth factor(NGF) has a critical role in peripheral nerve regeneration. The aim of this study is to construct a well-functioning hNGF-$\beta$ recombinat adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with adenovirus mediated hNGF-$\beta$ gene transfection into Schwann cells. First PCR associated cloning of GFP-tagged hNGF-$\beta$ which was ligated into E1/E3 deleted adenoviral vector was performed and tranfected into E. coli to construct hNGF-$\beta$ recombinant adenovirus. After production of recombinat adenovirus in a large scale, its transfection efficiency, expression, and function were evaluated using cell lines or primarily cultured cells of HEK293 cells, Schwann cells, fibroblast(NIH3T3) and myocyte(CRH cells). GFP expression was observed in 90% of infected cells compared to uninfected cells. Total mRNA isolated from hNGF-$\beta$ recombinat adenoviru infected cells showed strong RT-PCR band, however, LacZ recombinant adenovirus infected or uninfected cells did not. NGF quantification by ELISA showed a maximal release of 18.865 +/- 0.31ng/mL at 4th day. PC-12 cells exposed to media with hNGF-$\beta$ recombinant adenovirus infected Schwann cell demonstrated higher levels of differentiation compared with controls. We generated hNGF-$\beta$ recombinant adenovirus and induced over expression of NGF successfully in nonneuronal and neuronal cells. Following these result, it is expected to develop an improved treatment strategy peripheral nerve regeneration using the hNGF-$\beta$ gene transfected cells.

• Korean Journal of Materials Research
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• v.20 no.7
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• pp.356-363
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• 2010

For this paper, we investigated the area specific resistance (ASR) of commercially available ferritic stainless steels with different chemical compositions for use as solid oxide fuel cells (SOFC) interconnect. After 430h of oxidation, the STS446M alloy demonstrated excellent oxidation resistance and low ASR, of approximately 40 $m{\Omega}cm^2$, of the thermally grown oxide scale, compared to those of other stainless steels. The reason for the low ASR is that the contact resistance between the Pt paste and the oxide scale is reduced due to the plate-like shape of the $Cr_2O_3$(s). However, the acceptable ASR level is considered to be below 100 $m{\Omega}cm^2$ after 40,000 h of use. To further improve the electrical conductivity of the thermally grown oxide on stainless steels, the Co layer was deposited on the stainless steel by means of an electroless deposition method; it was then thermally oxidized to obtain the $Co_3O_4$ layer, which is a highly conductive layer. With the increase of the Co coating thickness, the ASR value decreased. For Co deposited STS444 with 2 ${\mu}m$hickness, the measured ASR at $800^{\circ}$ after 300 h oxidation is around 10 $m{\Omega}cm^2$, which is lower than that of the STS446M, which alloy has a lower ASR value than that of the non-coated STS. The reason for this improved high temperature conductivity seems to be that the Mn is efficiently diffused into the coating layer, which diffusion formed the highly conductive (Mn,Co)$_3O_4$ spinel phases and the thickness of the $Cr_2O_3$(S), which is the rate controlling layer of the electrical conductivity in the SOFC environment and is very thin

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.443-446
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• 2006

Carbon-supported Platinum (Pt) is the potential electro-catalyst material for anodic and cathodic reactions in fuel cell. Catalytic activity of the metal strongly depends on the particle shape, size and distribution of the metal in the porous supportive network. Conventional preparation techniques based on wet impregnation and chemical reduction of the metal precursors often do not provide adequate control of particle size and shape. We have proposed a novel route for preparing nano sized Pt colloidal particles in solution by oxidation of ethylene glycol. These Pt nano particles were deposited on large surface area carbon support. The process of nano Pt colloid formation involves the oxidation of solvent ethylene glycol to mainly glycolic acid and the presence of its anion glycolate depends on the solution pH. In the process of colloidal Pt formation glycolate actsas stabilizer for the Pt colloidal particle and prevents the agglomeration of colloidal Pt particles. These mono disperse Pt particles in carbon support are found uniformly distributed in nearly spherical shape and the size distribution was narrow for both supported and unsupported metals. The average diameter of the Pt nano particle was controlled in the range off to 3 nm by optimizing reaction parameters. Transmission electron microscopy, CV and RRDE experiments were used to compliment the results.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.446-450
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• 2000

The experiment was conducted to study the effects of water soluble vitamins and retinoic acid on the differentiation of preadipocyte from omental, subcutaneous, intermuscular and intramuscular adipose tissue of Hanwoo. Differentiation was assessed by the change in enzyme activity, glycerol-3 phosphate dehydrogenase in serum free cell culture system. Preadipocytes treated with biotin ($10{\mu}M$) and pantothenic acid ($100{\mu}M$) were significantly (p<0.05) less differentiated than those from the control in all adipose tissue depots except intramuscular tissue. Although there was no significance, vitamin C was shown to stimulate the adipocyte conversion in omental and subcutaneous, but not in intermuscular and intramuscular adipose tissues. Lower values of GPDH activity in intermuscular preadipocyte were interpreted to be caused by relatively higher amounts of protein. In this experiment vitamin C did not stimulate fat deposition in intramuscular adipose tissue but further experiments are needed on the role of vitamin C in preadipocyte differentiation. When treated with different levels of retinoic acids, differentiation of preadipocytes was significantly (p<0.05) reduced from the level of $0.5{\mu}g/ml$ in omental and intermuscular, from $50{\mu}g/ml$ in subcutaneous, and in intramuscular at $500{\mu}g/ml$, thus showing that intramuscular preadipocytes were least responsive to retinoic acid in differentiation. All-trans retinoic acid appeared to inhibit the differentiation in a dose dependent manner, regardless of adipose tissues type.