• Transactions of the Korean hydrogen and new energy society
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• v.15 no.1
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• pp.39-45
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• 2004

A 12-cell PEMFC stack was fabricated using the TiN-coated 316 stainless steel bipolar plates as substitute for the expensive and brittle graphite bipolar plates. Open cirtuit voltage and the maximum power of the stack was 12.08 V and 1.197 kW (199.5 A @ 6 V), respectively. Volumetric and gravimetric power density of the stack was calculated to be 373 W/L and 168 W/kg, respectively. Performance of each cell was quite uniform initially while degraded at a singnificantly different rate. During the 1,000 hr-operation at a constant load of 48 A, stack voltage decreased from 9.0 to 7.98 V at a degradation rate of 11 %/1,000 hr. However, degradation rate of each cell was in the wide rage from 1.2 to 31 %/1,000 hr.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.447-453
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• 2007

With a broad objective for the development of microbial based fertilizers, a total of 373 strains were isolated from rhizoplane and rhizosphere of pepper, tomato, lettuce, pasture, and grass. The efficacy of the isolates to augument overall plant growth was evaluated. After screening for their plant growth promotion and antagonistic properties in vitro efficient strains were further selected. The most efficient strains was characterized by 16S rRNA gene sequences and biochemical techniques and was designated as Bacillus subtilis S37-2. The strains facilitated plant growth and inhibited the plant phathogenic fungi such as Fusarium oxysporum (KACC 40037, Rhizoctonia solani (KACC 40140), and Sclerotinia sclerotiorum (KACC 40457). Pot based bioassay using lettuce as test plant was conducted by inoculating suspension ($10^5$ to $10^8cells\;mL^{-1}$) of B. subtilis S37-2 to the rhizosphere of lettuce cultivated in soil pots. Compared with non-inoculated pots, marked increase in leaf (42.3%) and root mass (48.7%) was observed in the inoculation group where the 50ml of cell mixture ($8.7{\times}10^8cells\;ml^{-1}$) was applied to the rhizosphere of letuce either once or twice. Antagonistic effects of B. subtilis S37-2 strain on S. sclerotiorum (KACC 40457) were tested. All the tested lettuce plants perished after 9 days in treatment containing only S. sclerotiorum, but only 17% of lettuce was perished in the inoculation plot. B. subtilis grew well in the TSB culture medium. The isolates grew better in yeast extracts than peptone and tryptone as nitrogen source. The growth rate was 2~4 times greater at $37^{\circ}C$ as compared with $30^{\circ}C$ incubation temperature. B. subitlis S37-2 produced $0.1{\mu}g\;ml^{-1}$ of IAA (indole 3-acetic acid) in the TSB medium containing L-tryptophan($20mg\;L^{-1}$) in 24 hours.

• Journal of Ginseng Research
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• v.36 no.1
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• pp.86-92
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• 2012

The glioblastoma multiforme (GBM) is the most common malignant brain tumor in adults. Despite combination treatments of radiation and chemotherapy, the survival periods are very short. Therefore, this study was conducted to assess the potential of ginsenoside $F_2$ (F2) to treat GBM. In in vitro experiments with glioblastoma cells U373MG, F2 showed the cytotoxic effect with $IC_{50}$ of 50 ${\mu}g/mL$ through apoptosis, confirmed by DNA condensation and fragmentation. The cell population of cell cycle sub-G1 as indicative of apoptosis was also increased. In xenograft model in SD rats, F2 at dosage of 35 mg/kg weight was intravenously injected every two days. This reduced the tumor growth in magnetic resonance imaging images. The immunohistochemistry revealed that the anticancer activity might be mediated through inhibition of proliferation judged by Ki67 and apoptosis induced by activation of caspase-3 and -8. And the lowered expression of CD31 showed the reduction in blood vessel densities. The expression of matrix metalloproteinase-9 for invasion of cancer was also inhibited. The cell populations with cancer stem cell markers of CD133 and nestin were reduced. The results of this study suggested that F2 could be a new potential chemotherapeutic drug for GBM treatment by inhibiting the growth and invasion of cancer.

• Tuberculosis and Respiratory Diseases
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• v.54 no.1
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• pp.57-70
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• 2003

Background : Small cell lung cancer represents approximately 20% of all carcinomas of the lung, and is recognized as having a poor long term outcome compared to non-small cell lung cancer. Therefore, this study investigated the prognostic factors in small cell lung cancer patients in order to improved the survival rate by using the proper therapeutic methods. Material and method : The clinical data from 394 patients who diagnosed with small cell lung cancer and treated from 1993 to 2001 at the Kosin University Gospel Hospital, were analyzed. Result : There were 314 male patients (79.7%), and 80 female patients (20.3%). The number of those with limited disease was 177 (44.9%), and the number of those with extensive disease was 217 (55.1%). Overall, 366 out of 394 enrolled patients had died. The median survival time was 215 days (95% CI : 192-237days). The disease stage, Karnofsky performance state, 5% body weight loss for the recent 3 months, chemotherapy regimens, and the additive chest radiotherapy were identified as being statistically significant factors for the survival time. The median survival times of the supportive care group, one anticancer therapy, and two or more treatment groups were 17 days, 211 days, and 419 day, respectively (p<0.001). These data emphasize the importance of anticancer treatment to improve survival time for patients. The group of concurrent chemoradiotherapy (30 patients) showed significantly longer survival time than the group given sequential chemoradiotherapy (55 patients) (528 days versus 373 days, p=0.0237). The favorable prognostic factors of laboratory study were groups of leukocyte =8,000/mm3, ALP=200 U/L, LDH=450 IU/L, NSE=15 ng/mL, s-GOT=40 IU/L. In extensive disease, there was no difference according to the number of metastatic site. However, the median survival time of patients with ipsilateral pleural effusion had longer than patients having other metastatic sites. According to the survey periods, three groups were divided into 1993-1995, 1996-1998, and 1999-2001. The median survival time was significantly prolonged after 1999 in comparison to previous groups (177 days, 194 days, 289 days, p=0.001, 0.002, respectively). Conclusion: Disease stage and 5% body weight loss for recent 3 months at diagnostic state were significant prognostic factors. In addition, the performance status, serum ALP, LDH, NSE, CEA levels also appear to be prognostic factors. The survival time of those patients with small cell lung cancer has been prologned in recent years. It was suggested that the used of the EP (etoposied and cisplatin) chemotherapy method and concurrent chemoradiotherapy for patients with a limited stage contributed to the improved survival time.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.373-377
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• 2012

This study was carried out in order to investigate the functional properties of 50% methanol extracts from four parts (root, stem, leaf and fruit) of Acanthopanax sessiliflorus by means of measuring the contents of eleutheroside B, E, and total polyphenols as well as determining electron donating ability (EDA), nitrite scavenging ability (NSA), and anticancer activity. The highest contents of eleutheroside B and E were found in the fruit (538.99 ${\mu}g/g$) and the stem (556.00 ${\mu}g/g$). The root extract demonstrated the highest polyphenol content (2.97 mg/g). EDA of the stem and root extracts were 90.21% and 85.71%. All of the extracts showed 81.5-93.0% of NSA at pH 1.2. In addition all extracts indicated no cytotoxicity to normal cell line (DC2.4). The root extract had a 23% inhibitory effect against the stomach cancer cell line (SNU-719). These results revealed that 50% methanol extracts from A. sessiliflorus can be used as a potential resource of nutraceuticals.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.517-523
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• 1996

From May 1988 to June 1994, )73 patients underwent exploratory thoracotomy for resection of non- small cell lung cancer, and 48 patients staged pathologically as lIIB were analyzed. 74 lesions were involvement of great vessel (n=26), heart (n=5), ipsilateral lung metastasis(n=4), esophagus (n=4), carina(n=3), mediastinum (n=2), trachea(n=1), spine (n=1) and 13lourO seeding(A=15). N3 lesions were involved in 6 patients. Extended pulmonary resection with radical mediastinal node dissection was possible in 25 patients, and exploration only was performed in 23 patients. The most frequent cause of unresectability was pleural seeding. Postoperative morbidity was )2 % (8125) and mortality was 16 % (41 25) in resected group. The adjutant therapy was given to 37 patients. The 1 year and 3 year survival for resected group ncluding operative deaths was 57.2%, and 2).8 % (median 15 months), but 48.4%, and 0 % (median 7 months) for exploration only group (Log-Rank test, p : 0.17). Our results suggest that extended pulmonary resection might be helpful for carefully selected patients with 74 non-small cell lung cancer, but meticulous preoperative work-up for staging, especially to detect pleural seeding and Invasion to the irlediastinal structures is a prerequisite to avoid unnecessary thoracotomy.

• Journal of the Korean Chemical Society
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• v.18 no.5
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• pp.373-380
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• 1974

Direct electrochemical preparation of periodate from iodide $(I^-{\to}{IO_4}^-)$ was investigated using a none-diaphragm cell and lead dioxide anode. The direct electrolytic conditions were combinations of the respectively results on the processes of iodate from iodide$(I^-{\to}{IO_3}^-)$, and periodate from iodate$({IO_3}^-{\to}{IO_4}^-)$ which were reported by the author, previously. The optimum condition was achieved when 1.0 M potassium iodide solution containing 0.5 g/l potassium dichromate as an anti-reducing agent was electrolyzed at anodic current density of $15{\AA}/dm^2$ and electrolytic temperature of $60^{\circ}C$. Under such a condition, the current efficiency was found to be 84 % at 98 % conversion of iodide to periodate. The explanation of electrode reaction was also given a consideration based on the polarization curves at lead dioxide anode in various electrolyte solutions.

• Molecules and Cells
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• v.37 no.3
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• pp.202-212
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• 2014

ClC-1 is a member of a large family of voltage-gated chloride channels, abundantly expressed in human skeletal muscle. Mutations in ClC-1 are associated with myotonia congenita (MC) and result in loss of regulation of membrane excitability in skeletal muscle. We studied the electrophysiological characteristics of six mutants found among Korean MC patients, using patch clamp methods in HEK293 cells. Here, we found that the autosomal dominant mutants S189C and P480S displayed reduced chloride conductances compared to WT. Autosomal recessive mutant M128I did not show a typical rapid deactivation of Cl- currents. While sporadic mutant G523D displayed sustained activation of $Cl^-$ currents in the whole cell traces, the other sporadic mutants, M373L and M609K, demonstrated rapid deactivations. $V_{1/2}$ of these mutants was shifted to more depolarizing potentials. In order to identify potential effects on gating processes, slow and fast gating was analyzed for each mutant. We show that slow gating of the mutants tends to be shifted toward more positive potentials in comparison to WT. Collectively, these six mutants found among Korean patients demonstrated modifications of channel gating behaviors and reduced chloride conductances that likely contribute to the physiologic changes of MC.

• Korean Journal of Veterinary Research
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• v.28 no.2
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• pp.285-297
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• 1988

The present study was conducted in order to get the normal hematologic values of Korean Jindo dogs. Blood samples were taken from 328(♂ 92, ♂ 236) healthy Jindo dogs in Jindo area. The results obtained in this study were summarized as follows: 1. The mean values of red blood cell(RBC) count, hemoglobin(Hb) content and packed cell volume(PCV) in the age group of less than one year were 6.77(♂ 6.80, ♂ 6.76)${\times}10^6/{\mu}l$, 13.14 (♂ 13.53, ♂ 12.99)g/100ml and 43.28(♂ 44.47, ♂ 42.79)ml/100ml, respectively, whereas the RBC count, Hb content and PCV in the age group of one year and more were 7.42(♂ 7.44, ♂ 7.42)${\times}10^6/{\mu}l$, 14.98(♂ 15.56, ♂ 14.76)g/100ml and 47.18 (♂ 48.43, ♂ 46.71)ml/100ml, respectively. The values of RBC count, Hb content and PCV appeared to be higher in the male than in the female and it increased with aging in the age group of less than one year. 2. The mean values of mean corpuscular volume(MCV), mean corpuscular hemoglobin(MCH) and mean corpuscular hemoglobin content(MCHC) in the age group of less than one year were 63.93(♂ 65.40, ♂ 63.30)fl, 19.41(♂ 19.90, ♂ 19.22) pg and 30.36(♂ 30.43, ♂ 30.36)g/100ml respectively, whereas the MCV, MCH and MCHC in the age group of one year and more were 63.58(♂ 65.09, ♂ 62.95)fl, 20. 19(♂ 20.91, ♂ 19.89) pg and 31.75(♂ 32.13, ♂ 31.60)g/100ml respectively. The values of MCV, MCH and MCHC appeared to be higher in the male than in the female. No differences were found in the MCV and MCH between age groups. The MCHC appeared to be higher in older age group. 3. The mean values of white blood cell(WBC) count in the age group of less than one year were 14,356(♂ 13,878, ♂ 14,551)/${\mu}l$, whereas the values of WBC count in the age group of one year and more were 13,394(♂ 12,656, ♂ 13,672)/${\mu}l$. The WBC count appeared to be higher in the female than in the male. No differences were found between age groups in the WBC count. 4. In WBC differential count the mean percentage of lymphocyte, monocyte, neutrophil and eosinophil of the age group less than one year were 33.45(♂ 31. 64, ♂ 34.18), 2.77(♂ 3.00, ♂ 2.68), 57.40(♂ 58.18, ♂ 57.08) and 6.38(♂ 7.18, ♂ 6.06)% respectively, while those of the age group one year and more were 30. 22(♂ 28.38, ♂ 30.90), 3.03(♂ 3.23, ♂ 2.95), 60.93(♂ 63.34, ♂ 60.03) and 5.82(♂ 5.04, ♂ 6.11)% respectively. Lymphocyte count appeared to be higher in the female and in the age group below one year than in the male and in the age group of one year and more, whereas the reverse was the case with neutrophil and monocyte counts. 5. Mean platelet count in the age group of less than one year was 377,391(♂ 398,778, ♂ 368,721)/${\mu}l$, whereas mean platelet count in the age group of one year and more was 354,657 (♂ 373,660, ♂ 347,512)/${\mu}l$. The platelet count appeared to be higher in the male than in the female and especially lower in the age group of three years and more($305,513/{\mu}l$) than in the other age groups.

• Childhood Kidney Diseases
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• v.20 no.2
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• pp.69-73
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• 2016

Purpose: The aim of this study was to compare the clinical and laboratory features of infants with roseola infantum due to human herpesvirus 6 (HHV6) infection and those with urinary tract infection (UTI). Methods: We retrospectively reviewed the medical records of children who were hospitalized at Cheil General Hospital and Women's Health Care Center, College of Medicine, Dankook University, and diagnosed as having HHV6 infection or UTI. Results: Among the infants admitted between September 2014 and May 2016, 92 (male, 45 and female, 47) were included in the study and divided into a HHV6 infection group (n=50) and a UTI group (n=42). The relative risk of UTI compared with that of HHV6 infection increased with pyuria (P<0.001), increased with leukocytosis (mean white blood cell [WBC] count, $15,048{\pm}5,756/mm^3$ vs $87,916{\pm}54,056/mm^3$; P<0.001), increased with C-reactive protein (CRP) level ($4.89{\pm}4.85 mg/dL$ vs $1.04{\pm}1.76mg/dL$; P<0.001), and younger age ($6.3{\pm}3.2months$ vs $18.3{\pm}12.6months$; P<0.001). The relative risk of HHV6 infection compared with that of UTI increased with fever duration ($4.3{\pm}1.7days$ vs $2.8{\pm}1.7days$; P<0.001) and decreased with platelet (PLT) count ($373{\pm}94{\times}10^3/mm^3$ vs $229{\pm}90{\times}10^3/mm^3$; P<0.001). No significant differences were found between the HHV6 groups according to the presence or absence of pyuria. Conclusion: Pyuria, age, fever duration, WBC count, CRP level, and PLT count were the differentiating factors of HHV6 infection from UTI. However, sterile pyuria can occur in children with HHV6 infection. In the presence of pyuria, CRP level and PLT count were the strong predictors of UTI compared with HHV6.