• KSBB Journal
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• v.22 no.4
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• pp.239-243
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• 2007

A method of forming agar microcapsule with fibroin coating was developed in this report. The capsules were prepared from a W/O emulsion of hot agar in mineral oil and were subsequently coated by fibroin. The capsules were harvested as precipitated aggregates, which can be dispersed in an aqueous media. The diameter of the microcapsule was less than $10{\mu}m$ by microscopic observation and 90% of them were between $1.32{\mu}m\;and\;6.0{\mu}m$. The structure of the aggregates and their dispersed microspheres were investigated by scanning electron microscope. Confocal microscopy was applied to visualize the core-shell structure of the agar microcapsule with fibroin coating. Thermogravimetric analysis (TGA) measured their composition to be agar 51.2%, fibroin 13.8%, Span 80 1.4% by weight.

• Korean journal of applied entomology
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• v.28 no.3
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• pp.105-112
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• 1989

The nuclear polyhedrosis viruses of Bombyx mori (BmNPV) and Hyphantria cunea (HcNPV) were characterized by electron microscopic observation, SDS-PAGE of polyhedral and virion proteins, and restriction endonuclease analysis of viral DNAs. Polyhedra of BmNPV were octadecahedral in shape with the diameter of $3 \mu\textrm{m}$, whereas those of HcNPV showed irregular appearances having the diameter of $1.5~2\mu\textrm{m}$. Under alkaline protease inactivated condition, polyhedral proteins of two NPVs were resolved into a major polypeptide, 30~31 KD, and several minor polypeptides by SDS-PAGE. Examination of virion proteins by silver staining after SDS-PAGE showed that BmNPV was composed of 47 polypeptides with M.W. range of 9.6~112 KD and HcNPV was composed of 48 polypeptides with M.W. range of 9.4~111 KD. The approximate genome size of two NPVs were determined by restriction endonuclease analysis: BmNPV and HcNPV were 114.6 Kb, respectively.

• Restorative Dentistry and Endodontics
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• v.42 no.3
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• pp.188-199
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• 2017

Objectives: This in vitro study evaluated the effect of dentin biomodifiers on the immediate and long-term bond strengths of a simplified etch and rinse adhesive to dentin. Materials and Methods: Flat coronal dentin surfaces were prepared in 120 extracted human molars. Teeth were randomly divided into 5 groups (n = 24) according to 5 different surface pre-treatments: No pre-treatment (control); 1M carbodiimide (EDC); 0.1% epigallocatechin-3-gallate (EGCG); 2% minocycline (MI); 10% sodium ascorbate (SA). After surface pre-treatment, adhesive (Adper Single Bond 2 [SB], 3M ESPE) was applied. Composite was applied into transparent plastic tubes (2.5 mm in diameter), which was placed over the bonded dentin surface. From each group, 10 samples were subjected to shear bond strength (SBS) evaluation at 24 hours (immediate) and remaining 10 samples were tested after 6 months (delayed). Additionally, 4 samples per group were subjected to scanning electron microscopic analysis for observation of resin-dentin interface. The data were statistically analysed with Shaperio-Wilk W test, 2-way analysis of variance (ANOVA), and post hoc Tukey's test. Results: At 24 hours, SBS of all surface pre-treatment groups were comparable with the control group, with significant differences found between EDC and SA groups only (p = 0.009). After 6 months storage, EDC, EGCG, and MI pre-treatments preserved the resindentin bond strength with no significant fall. Conclusions: Dentin pre-treatment with all the dentin biomodifiers except SA resulted in significant preservation of resin-dentin bond over 6 months storage period, without negatively affecting the immediate bond strength of the etch and rinse adhesive tested.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.235-241
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• 2017

The purpose of this study was to investigate the enhanced physiological activities of two Pichia strains, yeasts isolated from grapes pericarp. Based on phylogenetic analysis using 18S rRNA sequencing, two isolates were identified as Pichia manshurica GU-3 and Pichia terricola GU-4, respectively. The scanning electron microscopic analysis showed that the two isolates grown on YPD medium were of typical elliptical shape with buds and bud scars on cell surface. Physiological activities of the single and mixed Pichia cultures were monitored and compared. In mixed cultures after 72 h of incubation, the maximum activities of tyrosinase inhibition, ACE inhibition, and antioxidant were 81.7%, 45.9%, and 42.7%, respectively. Superoxide dismutase-like activity was approximately 30% in the mixed cultures. These studies demonstrate that Pichia species cultured in the form of mixture can enhance the physiological activities and has potential for the development of new bioactive products.

• Korean Journal of Plant Resources
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• v.20 no.5
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• pp.437-441
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• 2007

The argE gene of E.coli was introduced into #Ilmibyeo# cultivar of rice by Agrobacterium tumefaciens and a large number of transgenic plants were produced. Embryogenic calli were co-cultivated with A. tumefaciens strain AGL1 carrying the plasmid pCAMBIA1300 containing hygromycin resistance(HygR). Transgenic plants showing in vitro resistance to 50mg/L hygromycin were obtained using a selection procedure. Stable integration of argE and HPT genes into chromosomal DNA was proven by southern blot analysis and PCR analysis of genomic isolated from $T_0$ progenies. The fragments of 650 bp(HPT) were detected in transgenic rice lines. The 230 bp(argE) fragments were showed in agarose gel, and detected fragments were matched with size of argE specific primer. The microscopic feature of leaf on scanning electron microscope(SEM) revealed differences between clear and chalky in shape and arrangement of stoma but did not discriminate.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.188-203
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• 2023

Lysozymes are well-known antibacterial enzymes that mainly target the peptidoglycan layer of the bacterial cell wall. Animal lysozymes are mainly categorized as g-type, c-type, and i-type based on protein sequence and structural differences. In this study, c-type (AcLysC) and g-like-type (AcLysG-like) lysozymes from Amphiprion clarkii were characterized in silico via expressional and functional approaches. According to in silico analysis, open reading frames of AcLysC and AcLysG-like were 429 bp and 570 bp, respectively, encoding the corresponding polypeptide chains with 142 and 189 amino acids. Elevated expression levels of AcLysC and AcLysG-like were observed in the liver and the heart tissues, respectively, as evidenced by quantitative real-time polymerase chain reaction assays. AcLysC and AcLysG-like transcript levels were upregulated in gills, head kidney, and blood cells following experimental immune stimulation. Recombinant AcLysC exhibited potent lytic activity against Vibrio anguillarum, whereas recombinant AcLysG-like showed remarkable antibacterial activity against Vibrio harveyi and Streptococcus parauberis, which was further evidenced by scanning electron microscopic imaging of destructed bacterial cell walls. The findings of this study collectively suggest the potential roles of AcLysC and AcLysG-like in host immune defense.

• Applied Microscopy
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• v.32 no.3
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• pp.285-290
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• 2002

The therapeutic effect of safflower seed powder on experimental osteoporosis in the rat induced by ovariectomy was evaluated. Thirty Sprague-Dawley rats were ovariectomized at the age of 12 weeks. Seven weeks postovariectomy, rats were divided into two groups: control and safflower seed powder treated group. Five animals from each group were sacrificed at the following time points: 1, 3, and 5 weeks. Scanning electron microscopic observation and morphometric analysis of the tibiae epiphysis showed that the administration of safflower seed powder significantly prevented reduction of cortical bone width and bone volume compared with the control group. In conclusion, safflower seed powder contains something that prevent bone loss due to estrogen deficiency, and was effective in preventing the osteoporotic decrease of bone mass.

• Applied Microscopy
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• v.42 no.1
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• pp.1-7
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• 2012

The possibility of nanoparticles (NPs) in biotechnology had been discussed by biomedical investigators. Here we report to suggest a solution and problems when using electron microscopy to determine the distribution of quantum dots (QDs) nanoparticles that penetrate skin. The results of this study showed that NPs were able to penetrate stratum corneum (SC) and sebocyte via hair follicle. However, we have found artifacts such as nanoparticles that are produced from combination of free fatty acid and osmium tetroxide during specimen preparation. It is usually difficult to identify NPs. Therefore, we tried to resolve these problems by comparing the cross-correlation image pattern that are derived from the images of sample that had been processed differently. This method can contribute to more accurate interpretation and minimal errors during the analysis using quantum dot as tracer.

• Journal of the Korean Society for Heat Treatment
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• v.11 no.2
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• pp.140-149
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• 1998

The graphitization is affected by the addition of small amount of the elements, such as Si, Al, Ni, B, Cr and Mn etc. Boron is well known as the most effective element for the graphitization of cementite in high carbon steels. But a study on quantitative analysis of B effect on the graphitization is few reported. Therefore the effect of boron addition in Fe-0.65%C-1.0%Si-0.5%Mn steels on the graphitization is investigated quantitatively using hardness tester, optical microscope and scanning electron microscope, neutron induced microscopic radiography. The graphitization in high carbon steels is promoted with 0.003~0.005%B addition. But the graphitization in steels which has no boron takes long holding time at $680{\sim}720^{\circ}C$. The hardness of quenched steel containing 0.003%B is higher than that of 0.005%B added steel due to complete dissolution of fine graphites into the austenite. The 0.003%B added high carbon steel graphitized at $680^{\circ}C$ for 25hr is useful steel for the agricultural implements and automobile parts which needed a good formability and high hardness.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.5
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• pp.192-200
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• 2014

Purpose: The objective of this study was to evaluate the interaction between 4-hexylresorcinol (4HR) and antibody as that affects the performance of a silk-4HR combination graft for soft tissue augmentation in an animal model. Methods: The silk graft materials consisted of four types: silk+10% tricalcium phosphate (TCP) (ST0), silk+10% TCP+1% 4HR (ST1), silk+10% TCP+3% 4HR (ST3), and silk+10% TCP+6% 4-HR (ST6). The antibody binding assay tested the 4HR effect and scanning electron microscopic (SEM) exam was done for silk grafts. The animal experiment used a subcutaneous pocket mouse model. The graft - SH0 or SH1 or SH3 or SH6 - was placed in a subcutaneous pocket. The animals were killed at one, two, and four weeks, postoperatively. The specimens were subjected to histological analysis and lysozyme assay. Results: Groups with 4HR applied showed lower antibody binding affinity to antigen compared to groups without 4HR. In the SEM examination, there was no significant difference among groups. Histological examinations revealed many foreign body giant cells in ST0 and ST1 group at four weeks postoperatively. Both ST3 and ST6 groups developed significantly lower levels of giant cell values compared to ST0 and ST1 groups (P < 0.001) at four weeks postoperatively. In the lysozyme assay, the ST1 and ST3 groups showed denser signals than the other groups. Conclusion: 4HR combined silk implants resulted in high levels of vascular and connective tissue regeneration.