• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.699-705
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• 2000

The superoxide scavenging activities of thirteen kinds of herbal extracts were examined together with their cytotoxic and immunomodulating effects. The extracts of 6 kinds of herbs such as eucalyptus, mate, peppermint, sage, thyme and yarrow, so called medicinal herbs, showed above 70% of the superoxide scavenging activities. They also showed cytotoxicities against the cancer cell lines of Hepa-1c1c7 and KB-3-1 as well as the normal fibroblast cell line of mouse. The $IC_{50}$ values of above 6 herb extracts on the cancer cell lines were above or similar to the $IC_{50}$ values on the normal cell line, so it was unable to observe the herb extract which showed cytotoxicity only to the cancer cell lines. Considering the results of nitric oxide test that the sage extract was the only one having the immunomodulating effect(37% of positive control), there was no significant relationship between the superoxide scavenging activities of herbs and their immunomodulating effects.

• Journal of Aquaculture
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• v.19 no.3
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• pp.188-196
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• 2006

Annual reproductive cycle of small yellow croaker, Larimichthys polyactis were histologically investigated based on samples captured nearby the coast around Chujado, Youngkwang and Kanghwa, South Korea from February $2004{\sim}February$,2005. By histological survey, the annual reproductive cycle was classified into the following successive stages: The primary growth stage from September to October, the second growth stage from October to December, the mature stage from January to April, the final mature, ovulation and spawning stage from May to June, the degeneration stage from June to July and the rest stage from August to September. Throughout anatomical observation of the ovary, it is found that the small yellow croaker, L. polyactis belongs to an asynchronous and multiple spawner from late spring to early summer.

• Progress in Medical Physics
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• v.13 no.4
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• pp.224-228
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• 2002

Myocardial tagging technique such as spatial modulation of magnetization (SPAMM) allows the study of myocardial motion with high accuracy. However, the accuracy of the estimation of tag intersection can be affected by tagline spacing. The aim of this study was to investigate the relationship between tagline spacing of SPAMM image and tagging contrast-to-noise ratio (CNR) in in-vivo study. Two healthy volunteers were undergone electrocardiographically triggered MR imaging with SPAMM-based tagging pulse sequence at a 1.5T MR scanner. Horizontally modulated stripe patterns were imposed with a range from 3.6 to 9.6 mm of tagline spacing. Images of the left ventricle(LV) wall were acquired at the mid-ventricle level during cardiac cycle with FE-EPI (TR/TE = 5.8/2.2 msec, FA= 10$^{\circ}$. Tagging CNR for each image was calculated with a software which developed in our group. During contraction, tagging CNR was more rapidly decreased in case of narrow tagline spacing than in case of wide tagline spacing. In the same heart phase, CNR was increased corresponding with tagline spacing. Especially, at the fully contracted heart phase, CNR was more rapidly increased than the other heart phases as a function of tagline spacing. The results indicated that the optimization of tagline spacing provides better tagging CNR in order to analyze the myocardial motion more accurately.

• Polymer(Korea)
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• v.35 no.5
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• pp.378-384
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• 2011

Silk fibroin is a biocompatible and slowly biodegradable natural polymer. This natural polymer has excellent mechanical properties, non-toxicity, and non-immunogenic properties and has been demonstrated to support tissue regeneration. Also, gelatin is a natural material derived from collagen by hydrolysis and has an almost identical composition as that of collagen. Silk fibroin/gelatin scaffolds have been fabricated by using the freeze-drying method. To establish the scaffold manufacturing condition for silk fibroin and gelatin, we made scaffolds with various compositions of gelatin, glutaldehyde and silk fibroin. The silk fibroin/gelatin scaffolds were characterized using SEM, DSC, and water absorption ability tests. The cellular proliferation was evaluated by WST assay. These results suggested that a scaffold containing 8% of gelatin, 1% of glutaldehyde and 0.3 g of silk fibroin provided suitable characterstics for cell adhesion and proliferation. In conclusion, the silk fibroin/gelatin scaffold may serve as a potential cell delivery vehicle and a structural basis for tissue engineering.

• Polymer(Korea)
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• v.35 no.1
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• pp.7-12
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• 2011

Poly(lactic-co-glycolic acid) (PLGA) is a biodegradable synthetic polymer with acceptable mechanical strength and well-controlled degradation rate. Also, it can be easily fabricated into many shapes. Silk fibroin contains powerful bioactive molecules. We fabricated natural/synthetic hybrid films using 0, 10, 20, 40 and 80 wt% of silk fibroin. Schwann cells (SCs) were seeded on PLGA/silk fibroin hybrid films and confirmed the effects of adhesion and proliferation on SCs according to the content of silk fibroin. In this study, we confirmed PLGA/silk fibroin hybrid film containing 40% and 80% of silk fibroin interrupted adhesion and proliferation of SCs. Films containing 10% and 20% of silk, however, provided suitable environment for growth and proliferation of SCs. These results suggest that silk fibroin provides suitables surface to neural cells and its proper content provides proper culture conditions to improve cell adhesion and proliferation.

• Polymer(Korea)
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• v.37 no.2
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• pp.141-147
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• 2013

Poly(lactide-co-glycolic acid) (PLGA) has been widely used in the drug delivery and tissue engineering applications because of its good mechanical strength and biodegradation profile. However, cell attachment to the scaffold is low compared with that on fibrin although cells can be attached to the polymer surface. In this study, PLGA scaffolds were soaked in cells-fibrin suspension and polymerized with dropping fibrinogen-thrombin solution. Cellular proliferation activity was observed in PLGA/fibrin-seeded costal cartilage cells (CC) on 1, 3, and 7 days using the MTT assay and SEM. The effects of fibrin on the extracellular matrix (ECM) formation were evaluated using CC cell-seeded PLGA/fibrin scaffolds. The PLGA/fibrin scaffolds elicited more production of glycosaminoglycan (GAG) and collagen than the PLGA scaffold. In this study, fibrin incorporated PLGA scaffolds were prepared to evaluate the effects of fibrin on the cell attachment and proliferation in vitro and in vivo. In this result, we confirmed that proliferation of cells in PLGA/fibrin scaffolds were better than in PLGA scaffolds. The PLGA/fibrin scaffolds provide suitable environment for growth and proliferation of costal cartilage cells.

• Korean Journal of Optics and Photonics
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• v.30 no.6
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• pp.243-248
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• 2019

The respiratory tract is an essential part of the respiratory system involved in the process of respiration. However, if stenosis occurs, it interferes with breathing and can even lead to death. Asthma is a typical example of a reversible cause of airway narrowing, and the number of patients suffering from acute exacerbation is steadily increasing. Therefore, it is important to detect airway narrowing early and prevent the patient's condition from worsening. Optical coherence tomography (OCT), which has high resolution, is suitable for observing the microstructure of tissues. In this study we developed an endoscopic OCT system. We combined a 1300-nm OCT system with a servo motor, which can rotate at a high speed. A catheter was pulled back using a linear stage while imaging with 360° rotation by the motor. The motor was selected considering various requirements, such as torque, rotational speed, and gear ratio of pulleys. An ex vivo rabbit tracheal model was used as a sample, and the sample and catheter were immobilized by acrylic structures. The OCT images provided information about the structures of the mucosa and submucosa. The difference between normal and stenosed parts in the trachea was confirmed by OCT. Furthermore, through a three-dimensional (3-D) reconstruction process, it was possible to identify and diagnose the stenosis in the 3-D image of the airway, as well as the cross-sectional image. This study would be useful not only for diagnosing airway stenosis, but also for realizing 3-D imaging.

• Journal of Ginseng Research
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• v.28 no.1
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• pp.5-10
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• 2004

This study was carried out to investigate the effect of the active ingredients from ginseng on paraquat(PQ) toxicity. Oxidative stress was induced by intraperitreatneal injection of PQ at a single dose of 25 mg/kg. Saponin treated groups were given protopanaxadiol saponins(PPD) or protopanaxatriol saponins(PPT)(5 mg/kg, orally) per day for 1, 3, & 7 days. We also investigated the relationship between lipid peroxidation and ginseng saponins by measuring the levels of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase (GPx), reduced glutathione(GSH), malondialdehyde (MDA), and hydrogen peroxide(H$_2$O$_2$) in liver tissue. The activities of SOD, CAT, and GPx were generally high in the PPD group; the SOD activity on each day was the highest in the PPD group. The H$_2$O$_2$ content was the lowest in the PPD group. The GSH levels were significantly increased in the PPD. The levels of MDA(the end product of lipid peroxidation) were significantly lower in the red ginseng component groups than in the PQ group; the levels were especially low in the PPD groups. These results led us to conclude that the antioxidant effects of extracts from red ginseng prevent oxidative damage by direct antioxidant effects involving SOD, CAT, & GPx, and increasing the ability of the body to synthesize endogenous antioxidants.

• Korean Journal of Plant Resources
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• v.20 no.4
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• pp.367-374
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• 2007

This study was carried out to establish the micropropagation system of Bupleurum latissimum Nakai that is a Korean native endangered species. Callus were induced from the leaf, petiole and floral bud and the percentage of callus formation was highest in the floral bud on the MS medium containing 2.0 mg ${\cdot}$ $L^{-1}$ 2,4-D. Especially, callus induced from floral bud was formed 77.8% and the percentage of shoot formation was 42.6% on the MS medium containing 2.0 mg ${\cdot}$ $L^{-1}$ 2,4-D plus 1.0 mg ${\cdot}$ $L^{-1}$ TDZ. For simultaneously callus formation and shoot regeneration, 1/2 MS medium was more effective than MS medium. The percentage callus formation, shoot regeneration and rooting were 46.3%, 13.0%, 13.0% in 1/2 MS medium, respectively. Soot regeneration from callus was good in 1/2 MS medium supplemented with 2.0 mg ${\cdot}$ $L^{-1}$ 2,4-D plus 1.0 mg ${\cdot}$ $L^{-1}$ BA where percentage of shoot regeneration was 74.1 %, and the number of shoot per explant was 2.4. The percentage of rooting was lowest (57.8%) in control while it was highest (97.8%) in 1.5 mg ${\cdot}$ $L^{-1}$ NAA. In acclimatization of regenerated plantlets, the percentage of survived plantlets was highest (86.1%), and plant height, root length and fresh weight were good in the soil for horticulture.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.234-237
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• 2007

Calmodulin (CaM) is a $Ca^{2+}$-binding protein essential for biological functions mediated through $Ca^{2+}$-dependent mechanism. A cDNA clone for CaM was isolated from a cDNA library of olive flounder Paralichthys olivaceus. The CaM cDNA concists of 782 bp and encodes a polypeptide of 149 amino acids with four $Ca^{2+}$-binding motifs EF-hands (EF-I, EF-II, EF-III, and EF-IV). The deduced amino acid sequence of CaM shows 97-100% amino acid sequence identity to other CaM sequences. Semi-quantitative PCR analysis revealed that the CaM transcription was began during early development and the CaM mRNA is expressed highly in brain and intestine, and moderately in kidney, gill, and eye of healthy olive flounder. Taken together, CaM may be necessary for early olive flounder development and that it may have a part in homeostasis.