• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.4
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• pp.295-305
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• 2001

Protein kinase C (PKC) is known to play a pivotal role in neoplastic transformation cells and its high expression is often found in a variety of types of tumors including oral cancer. While PKC is associated with the altered signal transduction pathway of the tumor cells, it is still unclear which isoform is involved in the carcinogenesis process. Since the cellular distributions and the roles of PKC are isoform-specific, it is very important to identify the specific target molecules to improve our understanding of the carcinogenesis processes. Thus, the present study attempted to perform chemical carcinogen-induced neoplastic transformation of human epithelial cells and analyze the specific isoform of PKCs involved in the cellular transformation. The study analyzed overall PKC responses upon MNNG(N-Methyl-N'-nitro-N-nitroso guanidine) exposure with [$^3H$] PDBu binding assay. PKC translocation was observed at high doses of MNNG treatment in the presence of extracellular calcium. Such effects were not observed in the absence of extracellular calcium. Translocational effects with exposure of MNNG was further enhanced in the presence of hydrocortisone. The result suggests that the type of PKC involved may be $Ca^{2+}$-dependent classical isoform and steroid hormone enhances PKC activation. Among cPKC isoforms examined, only $PKC-{\alpha}$ and r showed significant translocation of protein levels from cytosolic fraction to membrane fraction, as analyzed by immunoblot. $PKC-{\varepsilon}$ in nPKC class showed an inch·eased translocation, but other forms in this class did not show the effect. None of isoforms in aPKC class was affected by MNNG treatment. The study demonstrated that there was a certain specificity in the patterns of isoform induction follwong chemical carcinogen exposure and helped identify all the types of PKC isoforms expressed in human epithelial cells. It was revealed that PKC isoforms were activated in an early resonse to chemical carcinogen, suggesting that PKC be associated with carcinogenesis process from an early stage in this particular cell system. The study will contribute to improving our understanding of chemical-induced carcinogenesis in human cells and may provide a scientific basis to introduce the specific PKC inhibitors as an anticancer drug of epithelial cell-origin cancers including oral cancer.

• Korean Journal of Animal Reproduction
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• v.18 no.2
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• pp.141-150
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• 1994

Morphological features of the interaction between the hatching blastocyst and implantation in pig were studied by electron microscopy. The observations extended from late blastocyst stage to the completion of trophoblastic erosion of the epithelium and early decidual transformation of the epithelium and early decidual transformation of the stromal cells. Between day 7 and 17 of pregnancy, blastocysts from 0.3 to 12 mm in diameter were flushed from the uterine horns of Dutch Landrace pigs. On the 7th of development in the pig blastocyst, the blastocyst shedded of the zona pellucida established the tips of microvilli and with bleb-like cytoplasmic protrusions of the epithelial cells. From day 11 on in pig embryo, the bilayered trophoblast undergoes a dramatic phase of elongation so that the initially spherical expanded blastocyst becomes tubular. In pig, close apposition to the uterine wall beg-ins at about 12 $^1$/$_2$ days and then attachment occurred during the afternoon of the 16th or 18th day post coitum. At this stage, embryonic loss compared with corpus luteum number is up to 40% of ovulated oocytes. Therefore, the implantation failture of these embryos may be mainly caused by morphological abnormality and failture of zona shedding.

• Korean Journal of Materials Research
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• v.30 no.4
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• pp.176-183
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• 2020

The high-temperature stability of YSZ specimens fabricated by die pressure and cold isostatic press (CIP) is investigated in CaCl₂-CaF₂-CaO molten salt at 1,150 ℃. The experimental results are as follows: green density 46.7 % and 50.9 %; sintering density 93.3 % and 99.3 % for die press and CIP, respectively. YSZ foremd by CIP exhibits higher stability than YSZ formed by die press due to denseness dependency after high-temperature stability test. YSZ shows peaks mainly attributed to CaZrO₃, with a small t-ZrO₂ peak, unlike the high-intensity tetragonal-ZrO₂ (t-ZrO₂) peak observed for the asreceived specimen. The t-ZrO₂ phase of YSZ is likely stabilized by Y₂O₃, and the leaching of Y₂O₃ results in phase transformation from t-ZrO₂ to m-ZrO₂. CaZrO₃ likely forms from the reaction between CaO and m-ZrO₂. As the exposure time increases, more CaZrO₃ is observed in the internal region of YSZ, which could be attributed to the inward diffusion of molten salt and outward diffusion of the stabilizer (Y₂O₃) through the pores. This results in greater susceptibility to phase transformation and CaZrO₃ formation. To use SOM anodes for the electroreduction of various metals, YSZ stability must be improved by adjusting the high-density in the forming process.

• KSBB Journal
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• v.10 no.1
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• pp.23-29
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• 1995

Calli were induced from leaf base region of germinated rice(Oryza sativa L. cv. Nakdong) with high frequency of up to 65% on LS medium supplemented with $2.5mg/{\ell}2$, 4-D in the dark at $27^{\circ}C$. Embryogenic calli of pale yellow, globular type were selected and used for the initiation of cell suspension cultures in AA2 liquid medium with $2mg/\ell$ 2,4-D, 0.2mg/$\ell$ kinetin arid $0.1mg/\ell$ GA3. Protoplasts were isolated from the embryogenic cell suspensions after 4 months of culture and then were electroporated with 400V/cm for 1 msec. Electroporated protoplasts divided with plating efficiency of 1.1% on PCM liquid medium supplemented with $2.5mg/\ell$ 2, 4-D, $0.1mg/\ell$ kinetin and 10mM proline. The protoplasts-derived microcalli were cultured on $0.2{\mu}m$ membrane fitter placed onto LS2.5 solid medium containing fine suspension cells as a feeder cells, for 2 weeks in the dark at $27^{\circ}C$. After an additional 2 weeks of culture under fluorescent light of $30{\pm}/3{\mu}E$.m^{-2}S^{-1}, yellow calli of 2mm diameter were transferred to regeneration medium. Shoots were produced from the green spot of protoplasts-derived calli and plants were regenerated form protoplast-derived green calli with frequencies of 11∼33%.

• Journal of Nutrition and Health
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• v.48 no.4
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• pp.310-318
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• 2015

Purpose: The aim of this study is to investigate anti-arthritis activity using natural eggshell membrane (NEM). Methods: NEM was administered at 52 mg/kg, 200 mg/kg, and 400 mg/kg to SD-Rat, where arthritis was induced by monosodium iodoacetate (MIA) at 3 mg. NO production in serum was measured using Griess reagent. Cytokines including IL-$1{\beta}$, and IL-6 were measured by Luminex and $PGE_2$, MMP-2, MMP-9, TIMP-1, $LTB_4$, and hs-CRP were measured by ELISA. The cartilage of patella volume was examined and 3-D high-resolution reconstructions of the cartilage of patella were obtained using a Micro-CT system. Results: Production of NO, IL-$1{\beta}$, IL-6, $PGE_2$, MMP-2, MMP-9, TIMP-1, $LTB_4$, and hs-CRP in serum was decreased, respectively, in comparison with control. The cartilage of patella volume increased significantly. In addition, the NEM group showed a decrease in the cartilage of patella, synovial membrane, and transformation of fibrous tissue. Conclusion: The results for NEM showed significant anti-arthritis activity. These results may be developed as a raw material for new health food to ease the symptoms mentioned above.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.187-187
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• 2012

In this report, the plasmonic nanopores of less than 5 nm diameter were fabricated on the apex of the pyramidal cavity array. The metallic pyramidal pit cavity can also utilized as the plasmonic bioreactor, and the fabricated Au or Al metallic nanopore can provide the controllable translocation speed down using the plasmonic optical force. Initially, the SiO2 nanopore on the pyramidal pit cavity were fabricated using conventional microfabrication techniques. Then, the metallic thin film was sputter-deposited, followed by surface modification of the nanometer thick membrane using FESEM, TEM and EPMA. The huge electron intensity of FESEM with ~microsecond scan speed can provide the rapid solid phase surface transformation. However, the moderate electron beam intensity from the normal TEM without high speed scanning can only provide the liquid phase surface modification. After metal deposition, the 100 nm diameter aperture using FIB beam drilling was obtained in order to obtain the uniform nano-aperture. Then, the nanometer size aperture was reduced down to ~50 nm using electron beam surface modification using high speed scanning FESEM. The followed EPMA electron beam exposure without high speed scanning presents the reduction of the nanosize aperture down to 10 nm. During these processes, the widening or the shrinking of the nanometer pore was observed depending upon the electron beam intensity. Finally, using 200 keV TEM, the diameter of the nanopore was successively down from 10 nm down to 1.5 nm.

• Journal of Korean Dental Science
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• v.6 no.2
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• pp.87-95
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• 2013

Synovial chondromatosis (SC) is a rare, benign disease found in metaplastic cartilaginous nodules within the synovial membrane. The etiology of SC is not well-known, but it may be associated with trauma, chronic abnormal loading, or inflammatory joint disease. It is often found in knee, elbow, ankle, and shoulder joint but rarely in the temporomandibular joint (TMJ) area. SC of TMJ frequently appears in middle age and more often in females. Clinical symptoms include periarticular swelling, pain, crepitus, and limitation of joint motion. The most common feature is a radiographic finding of loose bodies in the joint. Irregularity of joint space and condylar head is also observed. Treatment involves the surgical removal of synovium and loose bodies. The prognosis is good, with low postsurgical recurrence rate. Functional improvement of the joint and pain relief are noted in many patients. Malignant transformation of SC has not been recorded. In this study, we report a 54-year-old female patient who experienced discomfort on the right TMJ with SC on the area but made a satisfactory recovery after surgery.

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.438-445
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• 2009

We investigated global gene expression from both mouse liver and mouse hepatic cell lines treated with acetaminophen (APAP) in order to compare in vivo and in vitro profiles and to assess the feasibility of the two systems. During our analyses of gene expression profiles, we picked up several down-regulated genes, such as the cytochrome P450 family 51 (Cyp51), sulfotransferase family cytosolic 1C member 2 (Sult1c2), 3-hydroxy-3-methylglutaryl-Coenzyme A synthase 1 (Hmgcs1), and several genes that were up-regulated by APAP, such as growth arrest and DNA-damage-inducible 45 alpha (Gadd45a), transformation related protein 53 inducible nuclear protein 1 (Trp53inp1) and zinc finger protein 688 (Zfp688). For validation of gene function, synthesized short interfering RNAs (siRNAs) for these genes were transfected in a mouse hepatic cell line, BNL CL.2, for investigation of cell viability and mRNA expression level. We found that siRNA transfection of these genes induced down-regulation of respective mRNA expression and decreased cell viability. siRNA transfection for Cyp51 and others induced morphological alterations, such as membrane thickening and nuclear condensation. Taken together, siRNA transfection of these six genes decreased cell viability and induced alteration in cellular morphology, along with effective inhibition of respective mRNA, suggesting that these genes could be associated with APAP-induced toxicity. Furthermore, these genes may be used in the investigation of hepatotoxicity, for better understanding of its mechanism.

• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.233-244
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• 2002

As one of the serial studies on the taxonomy of Conthocamptus mirabilis species group in South Korea, C. semicirculus Kikuchi, widely distributed in the southern part of the Far East, and C. coreensis n. sp. from the middle west of South Korea are recorded. Intraspecific variability of some important characters like outer caudal setae and the spinous process of male leg 3 exopod was examined in Korean population of C. semicirculus. Canthocamptus coreensis n. sp. possesses the plesiomorphic characters of the round and narrow hyaline membrane of anal operculum and lacking the sexual reverse transformation in female caudal rami, while it also evolves the apomorphic ones of the modified outer apical setae of male leg 4 exopod and the spinous process of male leg 3 exopod. A key to the five species of the species group known from Korea is prepared.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.308-315
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• 1996

Osteoarthritis is a noninflammatory degenerative disease affecting the articular surfaces and is accompanied by remodeling of the underlying bone. The sympotms of osteoarthritis of the temporomandibular joint are pain in the joint and muscles of mastication, limitation. Osteoarthritis is generally accepted that several factors can contribute to the trauma, aging process, internal derangement and MPDS. Radiographic features of the osteoarthritis are seen flattening of joint, sclerosis on flattened area and osteophyte or anterior lipping. In the past, osteoarthritis was considered to self-limiting disease. Currently, synovial chondromembrane is part of the process of osteoarthritis secondary to trauma. Synovial chondromatosis is an uncommon disease of cartilaginous transformation of synovial membrane with formation of loose bodies within the joint space. The pathogenesis is more an active metaplastic than a neoplastic process. The cause of synovial chondromatosis is unknown. Although trauma and inflammation have all been cited as possible factors in tis pathogenesis. The clinical sign and symptoms are unilateral swelling of the joint region, pain in the joint area and crepitus seem to be the most reliable signs and symptoms. Radiographic evidence of loose bodies may or may not be present. This is a case report of 66 year old female with synovial chondromatosis, that is advanced disease of the osteoarthrits. We treated patient with surgical excision of lose bodies, diskectomy and synovectomy. The defected articular fossa area was reconstructed with temporalis fascia flap. The result was satisfactory.