• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.97-97
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• 2002

Human eryhropoietin (EPO) is acidic glycoprotein hormone that plays key role in hematopoiesis by facilitating differentiation of erythrocyte and formation of hemoglobin (Hb) and is used for the treatment of anemia. Human EPO is consist of 166 amino acids which is modified by three N-glycosylations (24, 38, 83) and single O-glycosylation (126). N-glycosylation is reported to be related to the cellular secretion and activity of EPO. In this study, we examined effects of mutagenesis in glycosylation site of recombinat hEPO for the cellular secretion during production from cultured CHO cell. We produced rhEpo which was cloned by PCR from human liver cDNA (TaKaRa) in cultured CHO cell. Using supernatant of the culture, ELISA assay and western analysis were performed. To estimate biological activity, 20IU of rhuEpo was subcutaneously injected into four ICR mice. After 8 days, HCT level was increased average 13 per cent, RBC was increased ca. 2${\times}$10$\^$6//${\mu}\ell$. In disease model Rat (anemia c-kit, WSRC-WS/WS), HCT was increased ca. 12%, RBC was increased ca. 1.6${\times}$10$\^$6//${\mu}\ell$. These results suggests that rhEpo we produced has biological activity. To remove glycosylation site by substituting 24, 38, 83, and 126th asparagine (or serine) with glutamic acid, overlapping -extension site-directed mutagenesis was performed. To add novel glycosylation sites, 69, 105th leucine was mutated to asparagine. Mutant EPO construct was transfected into CHO cell. Supernatant of the cell culture was analyzed using ELISA assay with monoclonal anti-EPO antibody (Medac, Germany). Since, several reports for mutagenesis of glycosylation sites showed case-by-case results, we examined both transient expression and stable expression. Addition of novel glycosylation sites resulted no secretion while deletion mutants had little effect except some double deletion mutants (24/83 and 38/83) and triple mutant. We suggest that not single but combination of glycosyl group affect secretion of EPO.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.5
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• pp.69-76
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• 2016

Current driving capability of MCT (MOS Controlled Thyristor) is determined by turn-off capability of conducting current, that is off-FET performance of MCT. On the other hand, having a good turn-on characteristics, including high peak anode current ($I_{peak}$) and rate of change of current (di/dt), is essential for pulsed power system which is one of major application field of MCTs. To satisfy above two requirements, careful control of on/off-FET performance is required. However, triple diffusion and several oxidation processes change surface doping profile and make it hard to control threshold voltage ($V_{th}$) of on/off-FET. In this paper, we have demonstrated the effect of $V_{th}$ adjustment ion implantation on the performance of MCT. The fabricated MCTs (active area = $0.465mm^2$) show forward voltage drop ($V_F$) of 1.25 V at $100A/cm^2$ and Ipeak of 290 A and di/dt of $5.8kA/{\mu}s$ at $V_A=800V$. While these characteristics are unaltered by $V_{th}$ adjustment ion implantation, the turn-off gate voltage is reduced from -3.5 V to -1.6 V for conducting current of $100A/cm^2$ when the $V_{th}$ adjustment ion implantation is carried out. This demonstrates that the current driving capability is enhanced without degradation of forward conduction and turn-on switching characteristics.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.1989-1992
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• 2014

Background: The aim of this study was to assess the response rates (clinical and pathological ) with docetaxel and epirubicin combination chemotherapy and its effect on outcome. Materials and Methods: We retrospectively analysed locally advanced breast cancer (LABC) patients who received NACT from January 2008 to December 2012 in our tertiary care centre. LABC constituted 37% of all breast cancer cases and 120 patients fulfilled the eligibility criteria. The regimens used for NACT were, six cycles of DEC (docetaxel $75mg/m^2$, epirubicin $75mg/m^2$, cyclophosphamide $50mg/m^2$ on Day 1, 3 weekly) and a sequential regimen (4 cycles of FEC, 5-flurouracil $600mg/m^2$, epirubicin $75mg/m^2$, cyclophosphamide $600mg/m^2$ followed by 4 cycles of docetaxel $85mg/m^2$). Results: The median age was 47 years (range 23-72). Ninety six ( 80 %) had T4 disease and 90% had clinically palpable lymph nodes at diagnosis. The median size of primary tumor at presentation was 5.9 cm. Hormone receptor positivity was seen in 55% and HER2/neu positivity, in 25%. Triple negative breast cancers constituted 25 % of the cases. The overall clinical response rate (complete or partial ) was 85% and pathological complete responses were obtained in 15%. Four cases defaulted, 5 patients died of treatment related toxicity and 15% developed febrile neutropenia on DEC. The median duration of follow up was 22 months. The median time to relapse was 20 months and the 3 year relapse free and overall survival rates were 50% and 70% respectively. Conclusions: LABC constituted 37% of all breast cancer cases at our institute. With NACT, pCR was seen in 15% of the cases. Sequential chemotherapy was better tolerated than concurrent anthracyline and taxane chemotherapy with a similar pCR.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1773-1777
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• 2016

Diagnostic and therapeutic radiation fields are planned so as to reduce side-effects while maximising the dose to site but effects on healthy tissues are inevitable. Radiation causes strand breaks in DNA of exposed cells which can lead to chromosomal aberrations and cause malfunction and cell death. Several researchers have highlighted the damaging effects of high dose radiation but still there is a lacuna in identifying damage due to low dose radiation used for diagnostic purposes. Blood is an easy resource to study genotoxicity and to estimate the effects of radiation. The micronucleus assay and chromosomal aberration can indicate genetic damage and our present aim was to establish these with lymphocytes in an in vitro model to predict the immediate effects low dose radiation. Blood was collected from healthy individuals and divided into 6 groups with increasing radiation dose i.e., 0Gy, 0.10Gy, 0.25Gy, 0.50Gy, 1Gy and 2Gy. The samples were irradiated in duplicates using a LINAC in the radiation oncology department. Standard protocols were applied for chromosomal aberration and micronucleus assays. Metaphases were stained in Giemsa and 200 were scored per sample for the detection of dicentric or acentric forms. For micronuclei detection, 200 metaphases. Giemsa stained binucleate cells per sample were analysed for any abnormality. The micronuclei (MN) frequency was increased in cells exposed to the entire range of doses (0.1-2Gy) delivered. Controls showed minimal MN formation ($2.0%{\pm}0.05$) with triple MN ($5.6%{\pm}2.0$) frequency at the lowest dose. MN formation increased exponentially with the radiation dose thereafter with a maximum at 2Gy. Significantly elevated numbers of dicentric chromosomes were also observed, even at doses of 0.1-0.5Gy, compared to controls, and acentric chromosomes were apparent at 2Gy. In conclusion we can state that lymphocytes can be effectively used to study direct effect of low dose radiation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5081-5086
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• 2012

Background: The liver is one of the most common metastatic sites of breast cancer, hepatic metastases developing in 6%-25% of patients with breast cancer and being associated with a poor prognosis. The aim of this study was to analyze the survival and clinical characteristics of patients with hepatic metastases from breast cancer of different molecular subtypes and to investigate the prognostic and predictive factors that effect clinical outcome. Methods: We retrospectively studied the charts of 104 patients with breast cancer hepatic metastases diagnosed at Sun Yat-sen University Cancer Center from December 1990 to June 2009. Subtypes were defined as luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) enriched, triple-negative (TN). Prognostic factor correlations with clinical features and treatment approaches were assessed at the diagnosis of hepatic metastases. Results: The median survival time was 16.0 months, and the one-, two- three-, four-, five-year survival rates were 63.5%, 31.7%, 15.6%, 10.8%, and 5.4%, respectively. Median survival periods after hepatic metastases were 19.3 months (luminal A), 13.3 months (luminal B), 18.9 months (HER2-enriched), and 16.1 months (TN, P=0.11). In multivariate analysis, a 2 year-interval from initial diagnosis to hepatic metastasis, treatment with endocrine therapy, and surgery were independent prognostic factors. Endocrine therapy could improve the survival of luminal subtypes (P=0.004) and was a favorable prognostic factor (median survival 23.4 months vs. 13.8 months, respectively, P=0.011). Luminal A group of patients treated with endocrine therapy did significantly better than the Luminal A group of patients treated without endocrine therapy (median survival of 48.9 vs. 13.8 months, P=0.003). Conclusions: Breast cancer subtypes were not associated with survival after hepatic metastases. Endocrine therapy was a significantly favorable treatment for patients with luminal subtype.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.136-143
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• 2004

The purpose of this study was to investigate the relationship between morphology and position of deciduous double teeth, and the occurrence of other dental anomalies in the same subject. Four morphological types were indentified according to Ailing's classification: type I, bifid crown-single root; type II, large crown-large root; type III, two fused crowns-single root; type IV, two fused crowns-two fused roots. Fifty-four double teeth were found in a total of 1,803 children, who had visited Wonkwang university hospital for dental treatment from January 1, 2003 to September 30, 2003. All of these children were examined clinically and intra-oral radiographs were taken. The results were as follows; 1. 49 children(2.7%) had more than one double teeth, 5 of these children had two double teeth on the bilateral side. And one child showed triple teeth which has three crowns and three roots. 2. Double teeth were predominantly situated in the anterior region, with a preference for the mandible. The ratio of cases involving central incisor and lateral incisor was higher than other cases. 3. There were 25 cases(46.2%) of missing successors among 54 cases of the double teeth. And, prevalence of the missing teeth was highest in the cases involving maxillary central incisor and lateral incisor. 4. In the case of type II(large crown-large root) had more missing successors.

• Journal of Chest Surgery
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• v.32 no.1
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• pp.22-26
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• 1999

Background: Treatment of adult patent ductus arteriosus(PDA) has many difficulty such as pulmonary hypertension, arterial wall calcification, aneurysmal chage of ductus. We tried to evaluate the effect of surgical interruption of PDA on postopeative change of heart size. Material and Method : From 1987 to 1997 we experienced 30 cases of the ligation of patent ductus arteriosus in adult at the department of cardiovacular surgery in Masan Samsung General Hospital. Result: There were 9 males and 21 females and their ages ranged from 16 to 44 years, with a mean age of 26.1 years. 15 patients had pulmonary hypertension and 9 patients complained of dyspnea with a degree of functional NYHA class III. Operation method was double or triple ligation using Teflon felt. Postoperative complications were wound dehiscence in 3 patients and transient hoarseness in 1 patient. The mean preoperative cardiothoracic ratio was 54.7%, and mean postoperative cardiothoracic ratio was 51.9%. The change of cardiothoracic ratio was more typical in the cases who had congestive heart failure. Their mean preoperative cardiothoracic ratio was 64.8% and the mean postoperative cardiothoracic ratio was 58.5% there was no postoperative deaths. Conclusion: We canclude that the improvement in cardiothoracic ratio may result from surgical intervention of PDA.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1081-1088
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• 2013

Two new metal-free organic dyes bridged by anthracene-mediated ${\pi}$-conjugated moieties were successfully synthesized for use in a dye-sensitized solar cell (DSSC). A N,N-diphenylthiophen-2-amine unit in these dyes acts as an electron donor, while a (E)-2-cyano-3-(thiophen-2-yl)acrylic acid group acts as an electron acceptor and an anchoring group to the $TiO_2$ electrode. The photovoltaic properties of (E)-2-cyano-3-(5-((10-(5-(diphenylamino)thiophen-2-yl)anthracen-9-yl)ethynyl)thiophen-2-yl)acrylic acid (DPATAT) and (E)-2-cyano-3-(5'-((10-(5-(diphenylamino)thiophen-2-yl)anthracen-9-yl)ethynyl)-2,2'-bithiophen-5-yl)acrylic acid (DPATABT) were investigated to identify the effect of conjugation length between electron donor and acceptor on the DSSC performance. By introducing an anthracene moiety into the dye structure, together with a triple bond and thiophene moieties for fine-tuning of molecular configurations and for broadening the absorption spectra, the short-circuit photocurrent densities ($J_{sc}$), and open-circuit photovoltages ($V_{oc}$) of DSSCs were improved. The improvement of $J_{sc}$ in DSSC made of DPATABT might be attributed to much broader absorption spectrum and higher molecular extinction coefficient (${\varepsilon}$) in the visible wavelength range. The DPATABT-based DSSC showed the highest power conversion efficiency (PCE) of 3.34% (${\eta}_{max}$ = 3.70%) under AM 1.5 illumination ($100mWcm^{-2}$) in a photoactive area of $0.41cm^2$, with the $J_{sc}$ of $7.89mAcm^{-2}$, the $V_{oc}$ of 0.59 V, and the fill factor (FF) of 72%. In brief, the solar cell performance with DPATABT was found to be better than that of DPATAT-based DSSC.

• Korean Journal of Materials Research
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• v.9 no.10
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• pp.1025-1031
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• 1999

Alloys of TiAl with six different compositions. i. e., Ti-(42, 44)Al-2Nb-4V. Ti-(42, 44)Al-4Nb-2V and Ti -(42, 44)Al-4Nb-2Cr, were manufactured by arc-melting. and their oxidation behavior was studied. Both isothermal and cyclic oxidation tests were performed at 700, 800 and $900^{\circ}C$ in air for 50hr. The oxidation resistance increased in the order of Ti-(42, 44)Al-2Nb-4V, Ti-(42, 44)Al-4Nb-ZV and Ti-(42, 44)Al-4Nb-2Cr. It was found that V was a deleterious element, while Cr was a beneficial element in terms of oxidation resistance. During oxidation, a simultaneous interdiffusion was observed. All the constituent elements in the base alloys diffused outward. whereas oxygen from the atmosphere diffused inward, to form triple oxide layers composed of an outermost $\textrm{TiO}_2$ layer. upper ($\textrm{TiO}_2+\textrm{Al}_2\textrm{O}_3$) mixed layer, and lower $\textrm{TiO}_2$-rich layer.

• Journal of Pharmaceutical Investigation
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• v.36 no.5
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• pp.343-348
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• 2006

The purpose of the present study was to evaluate the bioequivalence of two zolpidem tartrate tablets, Stilnox tablet(Sanofi-aventis Korea, reference product) and Zanilo tablet(ChoDang Pharm Co., Ltd., Korea, test product), according to the guidelines of Korea Food and Drug Administration(KFDA). After adding an internal standard(cimetropium), 250 ${\mu}L$ plasma samples were extracted using 1.3 mL of ethyl acetate. Extracted compounds were analyzed by HPLC with triple-quadrupole mass spectrometry. This method for determination of zolpidem is proved accurate and reproducible with the limit of quantitation of 1 ng/mL in human plasma. Twenty-four healthy male Korean volunteers received each medicine at the zolpidem tartrate dose of 10 mg in a $2{\times}2$ crossover study. There was one-week washout period between the doses. Plasma concentrations of zolpidem were monitored for over a period of 8 hr after the administration. $AUC_{0-t}$(the area under the plasma concentration-time curve) was calculated by the linear trapezoidal rule. $C_{max}$(maximum plasma drug concentration) and $T_{max}$(time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed $AUC_{0-t}$ and $C_{max}$. No significant sequence effect was found for all of the bio-availability parameters indicating that the crossover design was properly performed. The 90% confidence intervals for the log transformed data were acceptable range of log 0.8 to log 1.25(e.g., log 0.92-log 1.06 for $AUC_{0-t}$, log 0.96-log 1.13 for $C_{max}$). The major parameters, $AUC_{0-t}$ and $C_{max}$ met the criteria of KFDA for bioequivalence indicating that Zanilo tablet is bioequivalent to Stilnox tablet.