• Biomolecules & Therapeutics
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• v.12 no.2
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• pp.85-91
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• 2004

In all attempt to elucidate the role of apoptosis in drug resistance, cisplatin-resistant human chronic myelogenous leukemia (CML) K562 cells (K562/CDDP) were established and compared with drug sensitive parent cells (K562) in the induction of apoptosis. K562/CDDP cells were 5-fold more resistant to cisplatin compared to K562 cells. In addition, K562/CDDP cells were significantly more resistant to apoptois as judged by DNA fragmentation and DAPI staining. K562/CDDP cells exhibited decreased proleolytic activity of caspase-3 and this was further demonstrated by decreased cleavage of its substrate poly (ADP-ribose) polymerase (PARR- Western blot analysis showed that K562/CDDP cells had longer sustained levels of BCL-$X_L$ whereas no difference was noted in the level of Bcl-2. the translocation of Bax to mitochondria was significantly delayed in K562/CDDP cells. These results suggest that the reduced translocation of Bax and the sustained expression of BCL-$X_L$ may cause resistance to apoptosis through prevention of mitochondria release of cytochrome c, which subsequently induces reduction of caspase-3 activity and that this response is partly responsible for the acquired resistance to cisplatin ill K562 cells.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.352-355
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• 1987

The isolation and characterization of type II restriction endonuclease from Clostridium thermocellum ATCC 27405 were described. This enzyme (Cth I endonuclease) is an isoschizomer of Bcl I endonuclease recognizing 5'-TGATCA-3'. Cth I endonuclease requires MG$^{2+}$ ion for its activity and is maximally active at PH 1.5 to 10.5 in the Presence of 0 to 10mM NaCl. Cth I endonuclease is heat stable and has an optimum temperature of 6$0^{\circ}C$. The activity of Cth I enzyme is sensitive to dam methylation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2133-2139
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• 2014

4-Methylsulfinyl-3-butenyl isothiocyanate (MTBITC) found in the radish (Raphanus sativus L.), is a wellknown anticancer agent. In this study, the mechanisms of the MTBITC induction of cell apoptosis in human A549 lung cancer cells were investigated. Our PI staining results showed that MTBITC treatment significantly increased the apoptotic sub-G1 fraction in a dose-dependent manner. The mechanism of apoptosis induced by MTBITC was investigated by testing the change of mitochondrial membrane potential (${\Delta}{\Psi}m$), the expression of mRNAs of apoptosis-related genes by RT-PCR, and the activities of caspase-3 and -9 by caspase colorimetric assay. MTBITC treatment decreased mitochondrial membrane potential by down-regulating the rate of Bcl-2/Bax and Bcl-xL/Bax, and activation of caspase-3 and -9. Therefore, mitochondrial pathway and Bcl-2 gene family could be involved in the mechanisms of A549 cell apoptosis induced by MTBITC.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.209-209
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• 2009

ITO 박막은 박막 태양전지, 유기 태양전지뿐만 아니라 유연한 디스플레이, 발광다이오드와 같은 광학적 장치에 투명한 전극으로써 널리 사용된다. 글라스나 플라스틱 기판위에 형성된 투명 전극은 식각을 통하여 전기회로를 구성한다. 또한 식각 특성을 개선할 필요가 있다. 이 연구에서 우리는 유리 기판위에 코팅된 ITO 박막을 유도결합 $BCl_3/Ar$ 플라즈마를 이용하여 식각하였다. ITO 박막은 RF 마그네트론 스퍼터링을 사용해 200 $^{\circ}C$에서 비알칼리 글라스 위에 증착하였고 ITO 박막의 총 두께는 약 250 nm 이었다. 또한 전기 전도성은 $4.483{\times}10^{-4}{\Omega}cm$, 캐리어 농도는 $3.923{\times}10^{20}cm^{-3}$이고, 홀 이동도는 $3.545{\times}10cm^{-2}/Vs$이었다. Ar 플라즈마에 $BCl_3$ 가스를 첨가시키면서 가스 비율에 따른 ITO의 식각 속도와 ITO와 PR과의 선택비를 측정하였다. 최대 식각 속도는 $BCl_3$(25%)/Ar(75%), 500 W의 RF power, -200 V의 DC-bias voltage, 그리고 2 pa의 공정압력일 때 588 nm/min이었고 선택비는 0.43으로 다소 낮게 측정되었다. 식각된 표면의 화학적 반응은 엑스선 광전자 분광법 (X-ray Photoelectron Spectroscopy)을 사용해 조사되었다. 그리고 식각된 표면의 거칠기는 원자현미경 (Atomic Force Microscopy)을 사용해 측정하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3843-3849
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• 2013

This study was conducted to determine the effects of fetal bovine serum (FBS), bovine serum albumin (BSA) and epidermal growth factor (EGF) on blastocoel formation, total cell number, apoptosis and apoptosis-related gene expression of porcine diploid parthenotes developing in vitro. The addition of 0.4% BSA to the culture medium enhanced the development of 2-cell stage parthenotes to the blastocysts stage (p<0.01). Treatment of FBS reduced cell numbers of blastocysts (p<0.01) and increased the percentage of apoptosis in blastocysts (p<0.001). However, BSA increased cell numbers, only in the presence of EGF reverse-transcriptase polymerase chain reaction revealed that EGF enhanced the mRNA expression of Bcl-xL in the presence of 0.4% BSA but BSA and EGF alone had no effect. However, Treatment of FBS reduced Bcl-xL mRNA expression (p<0.05) and enhanced Bak expression. This result suggests that apoptosis related gene expression is significantly affected by supplements, which may result in alteration of apoptosis and embryo viability of porcine embryos developing in vitro.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.7
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• pp.731-736
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• 2012

A new method for producing boron-containing nanoparticles is described. Boron trichloride ($BCl_3$) and methane ($CH_4$) are dissociated through injection into a thermal plasma followed by a nucleation process producing boron or boron carbide nanoparticles. X-ray photoelectron spectroscopy was used to detect B-C bonds related to the carbide state and to probe the ratio of boron to carbon in the B-C bond structure. In addition, nanoparticles were characterized with scanning transmission electron microscopy and electron energy loss spectroscopy. It was found that nanoparticles were in the range 30-70 nm and a boron to carbon ratio in the B-C bond structure of up to 2 can be reached when $BCl_3$ of 20 sccm and $CH_4$ of 25 sccm were used.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1408-1414
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• 2008

The anticancer properties of Scolopendra subspinipes mutilans extract were investigated. The extract from S. subspinipes mutilans by 80% EtOH was fractionated with n-hexane, dichloromethan ($CH_2Cl_2$), ethylacetate (EtOAc), and butanol (BuOH) in order. The EtOAc fraction showed the highest inhibitory activity (about 80%) against human leukemia (HL-60) cell growth at $50\;{\mu}g/mL$. To explore the mechanism of cytotoxicity, we used several measures of apoptosis to determine whether these processes were involved in EtOAc fraction-induced HL-60 cell death. Our results showed EtOAc fraction induced cell shrinkage, cell membrane blebbing, apoptotic body, and DNA fragmentation. The EtOAc fraction gradually decreased the expression of anti-apoptotic Bcl-xL and led to the activation of caspase-3, -9 and cleavage of PARP. These findings suggest that S. subspinipes mutilans exhibits potential anticancer properties.

• The Journal of Korean Medicine
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• v.25 no.2
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• pp.67-76
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• 2004

Objectives : This study was designed to investigate the protective mechanisms of Palmul-tang on hypoxia-induced cytotoxicity in H9c2 cardiomyoblast cells. Methods : In this study, we used H9c2 cells. Cells were subjected to hypoxia in the absence and presence of $1000\mu\textrm{g}/ml$ Palmul-tang for 24 hrs. Cells were treated with various concentrations of Palmul-tang for 24 hrs. Cell viability was measured by MTT assay. Hypoxia markedly decreased the viability of H9c2 cells, which was characterized with apparent apoptotic features such as chromatin condensation as well as fragmentation of genomic DNA and nuclei. Results : Palmul-tang significantly reduced hypoxia-induced cell death and apoptotic characteristics. Also, Palmul-tang prevented mitochondrial dysfunction including the disruption of mitochondrial membrane permeability transition (MPT) and an increase in expression of apoptogenic Bcl-2 proteins in hypoxia-H9c2 cells. Conclusions; This study suggests that the protective effects of Palmul-tang against hypoxic damages may be mediated by the modulation of Bcl-2, Bax expression.

• BMB Reports
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• v.41 no.1
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• pp.11-22
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• 2008

Apoptosis (programmed cell death) is a cellular self-destruction mechanism that is essential for a variety of biological events, such as developmental sculpturing, tissue homeostasis, and the removal of unwanted cells. Mitochondria play a crucial role in regulating cell death. $Ca^{2+}$ has long been recognized as a participant in apoptotic pathways. Mitochondria are known to modulate and synchronize $Ca^{2+}$ signaling. Massive accumulation of $Ca^{2+}$ in the mitochondria leads to apoptosis. The $Ca^{2+}$ dynamics of ER and mitochondria appear to be modulated by the Bcl-2 family proteins, key factors involved in apoptosis. The number and morphology of mitochondria are precisely controlled through mitochondrial fusion and fission process by numerous mitochondria-shaping proteins. Mitochondrial fission accompanies apoptotic cell death and appears to be important for progression of the apoptotic pathway. Here, we highlight and discuss the role of mitochondrial calcium handling and mitochondrial fusion and fission machinery in apoptosis.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.804-808
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• 1998

The inductively coupled plasma(ICP) etching of platinum with BCl$_3$/Cl$_2$ gas chemistry has been studied. X-ray photoelectron spectroscopy (XPS) was used to investigate the chemical binding states of the etched surface. The plasma characteristics was extracted from optical emission spectroscopy (OES) and a single Langmuir probe. In this case of Pt etching using BCl$_3$/Cl$_2$ gas chemistries, the result of OES and Langmuir probe showed the increase of Cl radicals and ion current densities in the plasmas with increasing Cl$_2$ gas ratio. At the same time, XPS results indicated that the intensities of Pt 4f decreased with increasing Cl$_2$ gas ratio. The decrease of Pt 4f intensities implies the increase of residue layer thickness on the etched Pt surface.