• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.762-769
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• 2020

Vitamin K2 (menaquinone) is an essential vitamin existing in the daily diet, and menaquinone-7 (MK-7) is an important form of it. In a recent work, we engineered the synthesis modules of MK-7 in Bacillus subtilis, and the strain BS20 could produce 360 mg/l MK-7 in shake flasks, while the methylerythritol phosphate (MEP) pathway, which provides the precursor isopentenyl diphosphate for MK-7 synthesis, was not engineered. In this study, we overexpressed five genes of the MEP pathway in BS20 and finally obtained a strain (BS20DFHG) with MK-7 titer of 415 mg/l in shake flasks. Next, we optimized the fermentation process parameters (initial pH, temperature and aeration) in an 8-unit parallel bioreactor system consisting of 300-ml glass vessels. Based on this, we scaled up the MK-7 production by the strain BS20DFHG in a 50-l bioreactor, and the highest MK-7 titer reached 242 mg/l. Here, we show that the engineered strain BS20DFHG may be used for the industrial production of MK-7 in the future.

• Journal of Korean Society on Water Environment
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• v.28 no.6
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• pp.843-850
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• 2012

Due to the fast response to algae bloom issue in drinking water treatment plant, very fast determination methodology for algal toxin is required. In this study, column switching technique based online preconcentration method was combined with high resolution full scan mass spectrometer to save sample preparation time and to obtain fast and accurate result. After parameter optimization of online preconcentration, 1mL filtered sample was directly injected to trap column with switching valve system. Next, target toxins are eluted by 98% acetonitrile and analysed with 150 - 1,100 amu scan range at 50,000 resolving power. Method detection limit (MDL) for microcystin-LR, the most toxic isomer, was 0.1 ng/mL and others such as microcystin-YR, microcystin-RR and nodularin were 0.08, 0.03 and 0.04 ng/mL, respectively. This is the best improved sensitivities with 1mL volume in the literature. Furthermore, due to the use of ultra pressure HPLC (UPLC), the whole method run was completed in 4 min. Real sample applications for 173 sample including 55 surface water and 118 treatment plant samples for raw and treated water could be done within 16 hours. In our calculation, this methodology is roughly 80% faster than the previous manual solid-phase extraction with LC-MS/MS method.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.82-82
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• 1995

4-lBB molecule is expressed on the surface of activated CD4$\^$+/ and CD8$\^$+/ T cells. We generated a panel of anti-4-1 B5 murine mAbs using a fusion protein consisting of the extracellular domain of human 4-1 BB fused to Glutathione S-transferase. The binding activity against cell surface 4-1 BB molecule was assessed by flow cytometry analysis. These studies showed that several anti-4-1 BB mAbs bound to 10-30% of CD4$\^$+/ and CD8$\^$+/T cells in PHA or Con A stimulated PBLs, although these mAbs interacted with only, l-2% of CD4$\^$+/ and CD8$\^$+/ T cells in normal PBLs, indicating the specificity of mAbs to the 4-l BB molecule on activated CD4$\^$+/ and CD8$\^$+/ T cells. Next, we examined the effect of an anti-4-l BB mAb (4B4-1-1) on allogeneic mixed lymphocyte reactions (MLRs). The data indicated that the antibody significantly inhibited the proliferative response at higher concentrations. When tested with several T cell mitogens, the antibody had no stimulatory or inhibitory effects on the mitogen-mediated T cell proliferation. These data suggest that 4-1 BB molecule may play a role in the regulation of antigen-mediated immune response.

• Journal of Sensor Science and Technology
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• v.9 no.1
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• pp.44-50
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• 2000

Every object emits some energy from its surface. The emission energy forms surface heat distribution which we can capture by using an infrared thermal imager. The infrared thermal image may include valuable information regarding to the subsurface anomaly of the object. Since a thermal image reflects surface clutter and subsurface anomaly, we have difficulty in extracting the information on the subsurface anomaly only with thermal images taken under a wavelength. Thus, we use visible wavelength images of the object surface to remove exterior clutter. We, therefore in this paper, visualize the infrared image for overlaying it with a visible wavelength image. First, we make an interpolated image from two ordinary images taken from both sides of an infrared sensor. Next, we overlay the intermediate image with an infrared image taken from the infrared camera. The technique suggested in this paper can be utilized for analyzing the infrared images on non-destructive inspection against disaster and for safety.

• Journal of Pharmacopuncture
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• v.18 no.3
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• pp.49-56
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• 2015

Objectives: Anaphylactic shock can be fatal to people who become hypersensitive when bee venom pharmacopuncture (BVP) is used. Thus, sweet bee venom (SBV) was developed to reduce these allergic responses. SBV is almost pure melittin, and SBV has been reported to have fewer allergic responses than BVP. BVP has been administered only into acupoints or intramuscularly, but we thought that intravenous injection might be possible if SBV were shown to be a safe medium. The aim of this study is to evaluate the intravenous injection toxicity of SBV through a single-dose test in Sprague-Dawley (SD) rats. Methods: Male and female 6-week-old SD rats were injected intravenously with SBV (high dosage: 1.0 mL/animal; medium dosage: 0.5 mL/animal; low dosage: 0.1 mL/animal). Normal saline was injected into the control group in a similar method. We conducted clinical observations, body weight measurements, and hematology, biochemistry, and histological observations. Results: No death was observed in any of the experimental groups. Hyperemia was observed in the high and the medium dosage groups on the injection day, but from next day, no general symptoms were observed in any of the experimental groups. No significant changes due to intravenous SBV injection were observed in the weights, in the hematology, biochemistry, and histological observations, and in the local tolerance tests. Conclusion: The results of this study confirm that the lethal dose of SBV is over 1.0 mL/animal in SD rats and that the intravenous injection of SBV is safe in SD rats.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.120-126
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• 1989

This experiment was carried out to investigate the lectin of soybean (Glycine max L.) seed. Purification was done by 50-80% ammonium sulfate precipitation, CM-cellulose and Sephadex G-100 column. The purity was ascertained by electrophoresis. The molecular weight of purified lectin was estimated as 132,000. It was composed of three subunits which molecular weight was 45,000. The lectin was identified as glycoprotein by Schiff's reagent staining and Dubois method. The lectin agglutinated erythrocytes of rabbit and human. The amounts of the lectin to agglutinate human erythrocytes differed among the blood types: The blood type A required the least amount, the next was B, O, and AB in order. The agglutination was specifically inhibited by 5${\mu}$g/ml of N -acetyl.-D-galactoseamine and 200${\mu}$g/ml of D-galactose. Other tested sugars could not inhibit the agglutination of the erythrocytes by the lectin.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.2
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• pp.157-162
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• 2011

High temperature and stress are encounted in power plants and vehicle engines. Therefore, determination of the creep-fatigue life of a material is necessary prior to fabricating equipments. In this study, life design was determined on the basis of the lethargy coefficient for different temperatures, stress and rupture times. SP-Creep test data was compared with computed data. The SP-Creep test was performed to obtain the rupture time for X20CrMoV121 steel. The integration life equation was considered for three cases with various load, temperature and load-temperature. First, the lethargy coefficient was calculated by using the obtained rupture stress and the rupture time that were determined by carrying out the SP-Creep test. Next, life was predicted on the basis of the temperature condition. Finally, it was observed that life decreases considerably due to the coupling effect that results when fatigue and creep occur simultaneously.

• Journal of Microbiology and Biotechnology
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• v.29 no.9
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• pp.1478-1487
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• 2019

Ulcerative colitis (UC), a chronic inflammatory bowel disease, substantially impacts patients' health-related quality of life. In this study, an effective strategy for discovering high-efficiency probiotics has been developed. First, in order to survive in the conditions of the stomach and intestine, high bile salt-resistant and strong acid-resistant strains were screened out from the fecal flora of healthy adults. Next, the probiotic candidates were rescreened by examining the induction ability of IL-10 (anti-inflammatory factor) production in dextran sodium sulfate (DSS)-induced colitis mice, and Lactobacillus sakei 07 (L07) was identified and selected as probiotic P. In the end, fourteen bifidobacterium strains isolated from stools of healthy males were examined for their antimicrobial activity. Bifidobacterium bifidum B10 (73.75% inhibition rate) was selected as probiotic B. Moreover, the colonic IL-6 and $TNF-{\alpha}$ expression of the DSS-induced colitis mice treated with L. sakei 07 (L07) - B. bifidum B10 combination (PB) significantly decreased and the IL-10 expression was up-regulated by PB compared to the DSS group. Furthermore, Bacteroidetes and Actinobacteria decreased and Firmicutes increased in the DSS group mice, significantly. More interestingly, the intestinal flora biodiversity of DSS colitis mice was increased by PB. Of those, the level of B. bifidum increased significantly. The Bacteriodetes/Firmicutes (B/F) ratio increased, and the concentration of homocysteine and LPS in plasma was down-regulated by PB in the DSS-induced colitis mice. Upon administration of PB, the intestinal permeability of the the DSS-induced colitis mice was decreased by approximately 2.01-fold. This method is expected to be used in high-throughput screening of the probiotics against colitis. In addition, the L. sakei 07 - B. bifidum B10 combination holds potential in UC remission by immunomodulatory and gut microbiota modulation.

• Geomechanics and Engineering
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• v.30 no.2
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• pp.169-185
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• 2022

The urbanization and increasing rate of population demands effective means of transportation system (basement and tunnels) as well as high-rise building (resting on piled foundation) for accommodation. Therefore, it unavoidable to construct basements (i.e., excavation) nearby piled foundation. Since the basement excavation inevitably induces soil movement and stress changes in the ground, it may cause differential settlements to nearby piled raft foundation. To understand settlement and load transfer mechanism in the piled raft due to excavation-induced stress release, numerical parametric studies are carried out in this study. The effects of excavation depths (i.e., formation level) relative to piled raft were investigated by simulating the excavation near the pile shaft (i.e., H_e/L_p=0.67), next to (H_e/L_p=1.00) and below the pile toe (H_e/L_p=1.33). In addition, effects of sand density and raft fixity condition were investigated. The computed results have revealed that the induced settlement, tilting, pile lateral movement and load transfer mechanism in the piled raft depends upon the embedded depth of the diaphragm wall. Additional settlement of the piled raft due to excavation can be account for apparent loss of load carrying capacity of the piled raft (ALPC). The highest apparent loss of piled raft capacity ALPC (on the account of induced piled raft settlement) of 50% was calculated in in case of H_e/L_p = 1.33. Furthermore, the induced settlement decreased with increasing the relative density from 30% to 90%. On the contrary, the tilting of the raft increases in denser ground. The larger bending moment and lateral force was induced at the piled heads in fixed and pinned raft condition.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.65-69
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• 1985

For evaluation on the histopathologic studies, and age and sex distribution of the gastric carcinomas in the Taegu Area, the gastrectomized and gastoroscopic biopsy materials were collected at the Department of Pathology, College of Medicine, Yeungnam University, and the analyzed results were as follows: 1. In total of 350 cases of gastroscopic biopsy materials adenocarcinomas are 344 cases (98.3%), squamous cell carcinomas and undifferentiated carcinomas are only 6 cases (1.7%). In adenocarcinomas the most of all are tubular type, 215 cases (61.4%). In age distribution the highest is the 50th age group, and 120 cases (34.3%), the next, 60th, 81 cases (23.1%), 40th, 76 cases (21.7%), respectively. 2. In total of 130 cases of gastrectomized materials adenocarcinomas are 127 cases (97.7%), and are the highest incidence, the next, carcinomas originated from chronic peptic ulcer of the stomach, and are 3 cases (2.3%). In adenocarcinomas the highest are tubular type, 86 cases (66.2%), the next, signet-ring cell type, 20 cases (15.4%). The highest age incidence of the age group IS 50th, and the next, 60th, 40th, 30th, 70th and 10th age group, respectively.