• Journal of Korean Institute of Industrial Engineers
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• v.26 no.1
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• pp.73-80
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• 2000

To determine the exact direction and location of the human joint in motion is crucial in developing a more accurate human model and producing a more fitting artificial joint. There have been several reports on the biomechanical analysis of the joint to determine the anatomy and movement of joints. However, all the previous researches were made in vitro study, that is, they investigated the passive movement of the joint from cadavers and the suggested location of the joint axis was difficult to make practical applications due to the lack of the direction of joint axis. Also, in many biomechanical models, each joint axis is assumed to lie horizontally or vertically to the adjacent links. Such an assumption causes inherent inaccuracy. In this study, the direction and location of the transverse elbow axis was obtained with respect to the global coordinate system whose origin is on the lateral epicondyle of the humerus. The suggested result based on the global coordinate system lying on the external landmark will be helpful to understand the information of the axis and to make an application. From the experiments conducted for five subjects, the direction and location of the elbow transverse joint was determined for each subject by the helical axis method. A statistical validation was also performed to confirm the result. Finally, the result was applied to develop a simple elbow model which is a part of the kinematic arm model. The simple elbow movement model was developed to validate the significance of the result and the kinematic arm model was able to describe the geometry of any complex linkage system. As a result, the errors incurred from the proposed model were significantly reduced when compared to the ones from the previous approach.

• BMB Reports
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• v.50 no.2
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• pp.97-102
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• 2017

Patients with inflammatory bone disease or cancer exhibit an increased risk of fractures and delayed bone healing. The S100A4 protein is a member of the calcium-binding S100 protein family, which is abundantly expressed in inflammatory diseases and cancers. We investigated the effects of extracellular S100A4 on osteoblasts, which are cells responsible for bone formation. Treating primary calvarial osteoblasts with recombinant S100A4 resulted in matrix mineralization reductions. The expression of osteoblast marker genes including osteocalcin and osterix was also suppressed. Interestingly, S100A4 stimulated the nuclear factor-kappaB (NF-${\kappa}B$) signaling pathway in osteoblasts. More importantly, the ex vivo organ culture of mouse calvariae with recombinant S100A4 decreased the expression levels of osteocalcin, supporting the results of our in vitro experiments. This suggests that extracellular S100A4 is important for the regulation of bone formation by activating the NF-${\kappa}B$ signaling pathway in osteoblasts.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7611-7615
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• 2014

Aims: To prepare 5-fluorouracil (5-Fu) nanoparticles with higher encapsulation efficiency and drug loading, and then investigate interaction with the SGC-7901 gastric cancer cell line. Materials and Methods: Prescription was optimized by orthogonal experiments, the encapsulation efficiency and loading capacity were tested by high-performance liquid chromatography, and inhibition of proliferation by 5-Fu nanoparticles and 5-Fu given to cells for 24, 48 and 72 hours was investigated by methyl thiazolyl tetrazolium assay (MTT). In addition, 5-Fu nanoparticles were labeled by fluorescein isothiocyanate (FITC), and absorption into cells was tested by flow cytometry. Results: The optimal conditions for preparation were concentrations of 5-Fu of 5mg/ml, of $CaCl_2$ of 60 mg/ml and of chitosan of 2 mg/ml. With a stirring speed of 1200rpm, encapsulation efficiency of 5-Fu nanoparticles was $55.4{\pm}1.10%$ and loading capacity was $4.22{\pm}0.14%$; gastric cancer cells were significantly inhibited by 5-Fu nanoparticles in a time and concentration dependent manner, and compared to 5-Fu with slower drug release, in a certain concentration range, inhibition with 5-Fu nanoparticles was stronger. 5-Fu nanoparticles were absorbed by the cells in line with the concentration. Conclusions: 5-Fu nanoparticles can inhibit growth of gastric cancer cells in vitro to a greater extent than with 5-Fu with good adsorption characteristics, supporting feasibility as a carrier.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.690-695
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• 2005

The purpose of this thesis is to dedicate to get the objectivity of herbal medicine treatments by choosing herbs likely to work as antifungal agents against Candida albicans which is the causes of Candida vaginitis, making experiments on them and getting the significant results. Each herb's efficacy on control the number of Candida vaginitis is noticed by using Disk Susceptibility test with six herbs medicine and Broth dilution assay of the culture. Cinamon Ramulus, Pulsatillae Radix, Dictamni Radicis Cortex, Paeoniae Radix, Arecae Semen, Artemisiae Capillaries Herba extracts experimented on the efficiency of antifungal activities against Candida albicans by disk susceptibility test. Pulsatillae Radix has the strongest efficiency. In Dictamni Radicis Cortex never appeared antifungal effect on treatment. MIC (minimal inhibition concentration) in vitro antifungal agents of Cinamon Ramulus, Pulsatillae Radix, Paeoniae Radix, Artemisiae Capillaries Herba extracts against Candida albicans was determined by broth dilution assay. MIC against Candida albicans is that Pulsatillae Radix is 2.5 mg/ml and Cinamon Ramulus is 5 mg/ml and Paeoniae Radix is 10 mg/ml and Artemisiae Capillaries Herba is 40 mg/ml.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.1016-1021
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• 2005

The purpose of this thesis is to dedicate to get the objectivity of herbal medicine treatments by choosing herbs likely to work as antibacterial agents, Moutan Cortex Radicis, Caesalpiniae Lignum, Houttuyniae Herba, Forsythiae Fructus, Prunellae Herba, Scrophulariae Radix against Gardnerella vaginalis which is associated with Bacterial vaginosis, making experiments on them and getting the significant results. Each herb's efficacy on control the number of Bacterial vaginosis is noticed by using Disk Susceptibility test with six herbs medicine and Broth dilution assay of the culture. Disk Suseptibility Test : The efficiency strength is as follows in a row : Caesaipiniae Lignum, Moutan Cortex Radicis, Prunellae Herba, Forsythiae Fructus, Houttuyniae Herba, Scrophulariae Radix. MIC Prunellae Herba is 1.5 mg/ml, Caesalpiniae Lignum is 5 mg/ml, Forsythiae Fructus and Moutan Corex Radicis is 10mg/ml for G. vaginalis. As a results, herbmed which tested in this study have an antibacterial effects against G. vaginalis and that may be used for treament of Bacterial vaginosis. Assistant use of external medicine to p.o medicine is expected to bring the good effect of treatment which is used for the origin of this disease.

• Mycobiology
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• v.30 no.1
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• pp.31-36
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• 2002

Soil bacteria were screened for the ability to control cucumber anthracnose caused by Colletotrichum orbiculare through induced systemic resistance(ISR). Sixty-four bacterial strains having in vitro antifungal activity were used for selecting ISR-inducing strains in cucumber. Cucumber seeds(cv. Baeknokdadagi) were sown in potting mixtures incorporated with the soil bacteria, at a rate of ca. $10^8$ cells per gram of the mixture. Two week-old plants were then transplanted into the steam-sterilized soil. Three leaf-stage plants were inoculated with a conidial suspension($5{\times}10^5$ conidia/ml) of C. orbiculare. Diseased leaf area(%) and number of lesions per $cm^2$ leaf were evaluated on third leaves of the plants, $5{\sim}6$ days after inoculation. Among 64 strains tested, nine strains, GC-B19, GC-B35, GK-B18, MM-B22, PK-B14, RC-B41, RC-B64, RC-B65, and RC-B77 significantly(P=0.05) reduced anthracnose disease compared to the untreated control. In contrast, some bacterial strains promoted susceptibility of cucumber to the disease. From the repeated experiments using the nine bacterial strains, GC-B19, MM-B22, PK-B14, and RC-B65 significantly(P=0.05) reduced both diseased leaf area(%) and number of lesions per $cm^2$ leaf in at lease one experiment. These strains with control efficacy of $37{\sim}80%$ were determined to be effective ISR-inducing strains.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.11
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• pp.1191-1198
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• 2011

The use of a ventricular assist device (VAD) can raise the one-year survival rate without cardiac transplantation from 25% to 52%. However, malfunction of the VAD system causes 6% of VAD patients' deaths, which could possibly be avoided through the development of new VADs in which VAD malfunctions do not affect the patient's heart movement or hemodynamic state. A conventional VAD has an impeller or vane for propelling blood that can allow blood to regurgitate when the propelling force is weaker than the aortic pressure. In this paper, we developed a new pulsatile conduit-shaped VAD that has two valves. This device removes the possibility of blood regurgitation and has a small stationary area even when the pumping force is extremely weak. We estimated the characteristics of the device by measuring the outflow and the pressure of the pump in in-vitro and in-vivo experiments.

• Journal of Biomedical Engineering Research
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• v.21 no.4
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• pp.419-431
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• 2000

In this paper, a new beamforming technique is proposed, which can completely eliminate all the artifacts caused by digital scan converter. In the proposed method, named display-pixel-based focusing(DPBF) by the authors, ultrasound waves are focused directly at the display pixels instead of sampling points on the polar coordinate. Consequently. the DPBF system does not require the digital scan converter. To verify the proposed method, we modified a commercial scanner and performed experiments with a 3.5 MHz convex array and a 7.5 MHz linear array. We also defined and measured ICRA/B(Image Coarseness Ratio) to compare the image quality quantitatively. The experimental results with in vivo and in vitro data show that the proposed method improves the ICRA/B considerably, resulting in much smoother and finer images.

• Parasites, Hosts and Diseases
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• v.39 no.3
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• pp.233-240
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• 2001

Although some reports have been published on the protective effect of antibodies to Toxoplasma gondii surface membrane proteins, few address the inhibitory activity of antibodies to dense granular proteins (GRA proteins) . Therefore, we performed a series of experiments to evaluate the inhibitory effects of monoclonal antibodies (mAbs) to GRA proteins (GRA2, 28 kDa; GRA6, 32 kDa) and surface membrane protein (SAGI, 30 kDa) on the invasion of T. gondii tachyzoites. Passive immunization of mice with one of three mAbs following challenge with a lethal dose of tachyzoites significantly increased survival compared with results for mice treated with control ascites. The survival times of mice challenged with tachyzoties pretreated with anti-GRA6 or anti-SAG 1 mAb were significantly increased. Mice that received tachyzoties pretreated with both mAb and complement had longer survival times than those that received tachyzoites pretreated with mAb alone. Invasion of tachyzoites into fibroblasts and macrophages was significantly inhibited in the anti-GRA2, anti-GRA6 or anti-SAG 1 mAb pretreated group. Pretreatment with mAb and complement inhibited invasion of tachyzoites in both fibroblasts and macrophages. These results suggest that specific antibodies to dense-granule molecules may be useful for controlling infection with T. gondii.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.162-169
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• 2021

Global warming has affected the distribution of organisms for decades and has displayed rapid ascent recently. Research into the effects on tropical organisms are vital. Padina boryana is a resourceful marine microalgae in the Maldives Sea in the Laccadive region. A 70% ethanol extraction (PBE) of this seaweed was used to investigate its antioxidant potential. Both in vitro and in vivo models were implemented. PBE exhibited protective potential against H₂O₂ induced apoptosis. ROS levels were suppressed due to PBE. PBE expressed a cytoprotective nature. In vivo experiments involving the zebra fish model conformed its validity. The antioxidant efficacy of PBE was dose dependent. Study outcomes suggest PBE has potential as a novel and valuable marine resource to aid the functional food and cosmeceutical industries.