• Food Science and Biotechnology
• /
• v.16 no.3
• /
• pp.457-462
• /
• 2007

Histone acetyltransferase (HAT) is a family of enzymes that regulate histone acetylation. Dysfunction of HAT plays a critical role in the development of cancer. Here we have screened the various plant extracts to find out the potent HAT inhibitors. The bellflower (Platycodon grandiflorum) root have exhibited approximately 30% of the inhibitory effects on HAT activity, especially p300 and CBP (CREB-binding protein) at the concentration of $100\;{\mu}g/mL$. The cell viability was decreased approximately 52% in LNCaP cell for 48 hr incubation. Furthermore, mRNA level of 3 androgen receptor target genes, PSA, NKX3.1, and TSC22 were decreased with bellflower root extract treatment ($100\;{\mu}g/mL$) in the presence of androgen. In ChIP assay, the acetylation of histone H3 and H4 in PSA promoter region was dramatically repressed by bellflower root treatment, but not TR target gene, Dl. Therefore, the potent HAT inhibitory effect of bellflower root led to the decreased transcription of AR target genes and prostate cancer cell growth with the repression of histone hyperacetylation.

• Korean Journal of Materials Research
• /
• v.26 no.4
• /
• pp.222-227
• /
• 2016

Tin oxides have been studied for various applications such as gas detecting materials, transparent electrodes, transparent devices, and solar cells. p-type SnO is a promising transparent oxide semiconductor because of its high optical transparency and excellent electrical properties. In this study, we fabricated p-type SnO thin film using rf magnetron sputtering with an SnO/Sn composite target; we examined the effects of various oxygen flow rates on the SnO thin films. We fundamentally investigated the structural, optical, and electrical properties of the p-type SnO thin films utilizing X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV/Vis spectrometry, and Hall Effect measurement. A p-type SnO thin film of $P_{O2}=3%$ was obtained with > 80% transmittance, carrier concentration of $1.12{\times}10^{18}cm^{-3}$, and mobility of $1.18cm^2V^{-1}s^{-1}$. With increasing of the oxygen partial pressure, electrical conductivity transition from p-type to n-type was observed in the SnO crystal structure.

• Proceedings of the KIEE Conference
• /
• 2003.10a
• /
• pp.89-91
• /
• 2003

The determination of DNA hybridization reaction can apply the molecular biology research, clinic diagnostics, bioengineering, environment monitoring, food science and other application area. So, the improvement of DNA detection system is very important for the determination of this hybridization reaction. In this study, we report the characterization of the probe and target oligonucleotide hybridization reaction using the evanescent field microscopy. First, we have fabricated DNA chip microarray. The particles which were immobilized oligonucleotides were arranged by the random fluidic self-assembly on the pattern chips, using hydrophobic interaction. Second, we have detected DNA hybridization reaction using evanescent field microscopy. The 5'-biotinylated probe oligonucleotides were immobilized on the surface of DNA chip microarray and the hybridization reaction with the Rhodamine conjugated target oligonucleotide was excited fluorescence generated on the evanescent field microscopy. In the foundation of this result, we could be employed as the basis of a probe olidonucleotide, capable of detecting the target oligonucleotide and monitoring it in a large analyte concentration range and various mismatching condition.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.675-675
• /
• 2013

CIGS thin films have received a great attention as a promising material for solar cells due to their high absorption coefficient, appropriate bandgap, long-term stability, and low cost production. CIGS thin films have been deposited by various methods such as co-evaporation, sputtering, spray pyrolysis and electro-deposition. In this study, Cu(In,Ga)Se2(CIGS) thin films were prepared using a single quaternary target by rf magnetron sputtering. The effect of sulfurization on the structural, compositional and electrical properties of the films was examined in order to develop the deposition process. An optimal sulfurization process will be selected for the preparation of CIGS thin films with good structural, optical and electrical properties by applying various sulfurization processes. In addition, the electrical properties of CIGS thin films were investigated by post-deposition annealing process. The carrier concentration of CIG(SSe) thin films after sulfurization was increased from $10^{14}cm^{-3}$ to $10^{16}cm^{-3}$ and the resistivity was increased from 10 ${\Omega}cm$ to $10^3$ ${\Omega}cm$. It is confirmed that CIG(SSe) thin films prepared at optimal deposition condition have similar atomic ratio to the target value after sulfurization.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.11C no.3
• /
• pp.85-90
• /
• 2001

The determination of DNA hybridization reaction can apply the molecular biology research, clinic diagnostics, bioengineering, environment monitoring, food science and other application area. So, the improvement of DNA detection system is very important for the determination of this hybridization reaction. In this study, we report the characterization of the probe and target oligonucleotide hybridization reaction using the evanescent field microscopy. First, we have fabricated DNA chip microarray. The particles which were immobilized oligonucleotides were arranged by the random fluidic self-assembly on the pattern chips, using hydrophobic interaction. Second, we have detected DNA hybridization reaction using evanescent field microscopy. The 5'-biotinylated probe oligonucleotides were immobilized on the surface of DNA chip microarray and the hybridization reaction with the Rhodamine conjugated target oligonucleotide was excited fluorescence generated on the evanescent field microscopy. In the foundation of this result, we could be employed as the basis of a probe olidonucleotide, capable of detecting the target oligonucleotide and monitoring it in a large analyte concentration range and various mismatching condition.

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.2
• /
• pp.91-96
• /
• 2007

The measurement of pathologically low levels of tissue $pO_2$ is an important diagnostic goal for determining the prognosis of many clinically important diseases including cardiovascular insufficiency, stroke and cancer. The target tissues nowaday have mostly been tumors or the myocardium, with less attention centered on the brain. Radiolabelled nitroimidazole or derivatives may be useful in identifying the hypoxic cells in cerebrovascular disease or traumatic brain injury, and hypoxic-ischemic encephalopathy. In acute stroke, the target of therapy is the severely hypoxic but salvageable tissue. $^{18}F-MISO$ PET and $^{99}mTc-EC-metronidazole$ SPECT in patients with acute ischemic stroke identified hypoxic tissues and ischemic penumbra, and predicted its outcome. A study using $^{123}I-IAZA$ in patient with closed head injury detected the hypoxic tissues after head injury. Up till now these radiopharmaceuticals have drawbacks due to its relatively low concentration with hypoxic tissues associated with/without low blood-brain barrier permeability and the necessity to wait a long time to achieve acceptable target to background ratios for imaging in acute ischemic stroke. It is needed to develop new hypoxic marker exhibiting more rapid localization in the hypoxic region in the brain. And then, the hypoxic brain imaging with imidazoles or non-imidazoles may be very useful in detecting the hypoxic tissues, determining therapeutic strategies and developing therapeutic drugs in several neurological disease, especially, in acute ischemic stroke.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2000.11a
• /
• pp.12-12
• /
• 2000

This paper investigated the effect of the film deposition rate for $CrN_x$ microstructure and mechanical properties. For these purpose, pure Cr an stoichiometric CrN films were deposited with various target power density on Si hardened M2 tool steel. The variation of ni trogen concentration in $CrN_x$ f analyzed by AES and deposition rate was calculated by measuring of thickness using ${\alpha}-step$ profilometer. The microstructure was analyzed by X-Ray Diffract and Scanning Electron Microscopy(SEM), and mechanical properties were evalua residual stress, microhardness and adhesion tests. Deposition rate of Cr and CrN increased as an almost linear function of target power density from $0.25\mu\textrm{m}/min$ and $0.15\mu\textrm{m}/min$ to $0.43\mu\textrm{m}/min$. Residual stresses of Cr and CrN films were from tensi Ie to compressive stress with an increase of deposi tion rate a compressive stresses were increased as more augmentation of deposition r maximum hardness value of $2300kg/\textrm{mm}^2$ and the best adhesion strength correspond HF 1 were obtained for CrN film synthesized at the highest target densitY($13.2W/\textrm{mm}^2$) owing to high residual compressive stress and increasing mobility.

• Environmental Engineering Research
• /
• v.17 no.4
• /
• pp.217-225
• /
• 2012

In this study, the treatability of two target contaminants during the Fenton reaction, n-hexadecane and 1-methylnaphthalene, was evaluated as a function of the amounts of $FeCl_2$ and $H_2O_2$ injected into open and closed reaction systems. In the Fenton reaction of n-hexadecane and 1-methylnaphthalene, the mass recovery of the target contaminants was above 95% in the closed system. However, when the Fenton reaction was performed with high amounts of $H_2O_2$ and $FeCl_2$ injected in the open system, a reduction of approximately 40% of the initial mass of 1-methylnaphthalene was observed. This trend may be explained by the unique physical properties of 1-methylnaphthalene, which has higher volatility than n-hexadecane. Further, this trend was well correlated with the rise in high temperature at the initial reaction stage. Considering the mass recovery of the two target contaminants, the reaction temperature, and the residual concentration of $H_2O_2$ at different amounts of $FeCl_2$ and $H_2O_2$ injected, it can be suggested that the Fenton reaction should be performed with controlled conditions that can provide a suitable reaction environment between oxidant and contaminants.

• Journal of the Korean institute of surface engineering
• /
• v.47 no.6
• /
• pp.311-315
• /
• 2014

Indium tin oxide (ITO) thin films (30 nm) were deposited on PET substrate by reactive DC magnetron sputtering using In/Sn(2, 5 wt.%) metal alloy target without intentionally substrate heating during the deposition under different DC powers of 70 ~ 110 W. The electrical properties were estimated by Hall-effect measurements system. The resistivity of ITO thin film deposited using In/Sn (5 wt.%) metal alloy target at low DC power increased with increasing annealing time. However, they increased with increasing annealing time at high DC power. In the case of ITO (Sn 2 wt%), we can't find clear change in resistivity with increasing annealing time. However, carrier density and mobility showed difference behavior due to change of oxygen vacancy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.34 no.2
• /
• pp.99-104
• /
• 2021

Ion-beam sputtering (IBS) was used to deposit semiconducting IZTO (indium zinc tin oxide) thin films onto heavily-doped Si substrates using a sintered ceramic target with the nominal composition In0.4Zn0.5Sn0.1O1.5, which could work as a channel layer for oxide TFT (oxide thin film transistor) devices. The crystallization behavior and electrical properties were examined for the films in terms of deposition parameters, i.e. target tilt angle and substrate temperature during deposition. The thickness uniformity of the films were examined using a stylus profilometer. The observed difference in electrical properties was not related to the degree of crystallization but to the deposition temperature which affected charge carrier concentration (n), electrical resistivity (ρ), sheet resistance (Rs), and Hall mobility (μH) values of the films.