양극산화에 의한 티타늄 산화피막의 전기화학적 거동과 형상

변기정,김진수,김교한,Byeon K.J.,Kim C.S.,Zhu Xiaolong,Kim K.H. 대한의용생체공학회 2000 의공학회지 Vol.21 No.3

The galvanostatic anodization of commercially Pure titanium plate (c.p.Ti, grade 2) was investigated in various concentrations of aqueous $H_3PO_4$ from 0.05M to 0.7M. The surfaces of anodic oxide films, formed by the current density in the range between 0.3 and $l.0 A/dm^2$. were analyzed by SEM and XRD. The voltage-time (V-T) curves displayed an initial linear part and a subsequent parabolic part, and the initial slopes increased with an increase in the current density in 0.05M $H_3PO_4$. As the concentration of the electrolyte increased, the V-T corves exhibit no change but the final voltage decreased. The anodic oxide film of titanium developed from fine grains to snowflake-like grains in a layered structure with an increase in the concentration of the electrolyte and current density. Sparking at the interface of the oxide/electrolyte accompanied the local deposition and dissolution of the oxide film through discharging. The crystallinity of the anodic oxide film increased with the anodizing voltage and decreased with an increase in the concentration of the electrolyte.

Pierre Robin 症候群의 一例

卞基禎 대한치과의사학회 1994 대한치과의사학회지 Vol.15 No.8

가령에 따른 흰쥐 하악과두 섬유층의 미세구조 및 교원원섬유의 변화

변기정,Byeon, Ki-Jeong 대한악안면성형재건외과학회 1998 Maxillofacial Plastic Reconstructive Surgery Vol.20 No.4

The fibrous layer of mandibular condyle of the neonatal, 1-, 7-, 14-, 27-, 55-days and 1 year old rats were examined in the electron microscope with particular attention to the ultrastructure and diameter of collagen fibrils. In the 1-day rats, most of the cells of the fibrous layer were undifferentiated mesenchymal cells and fibroblasts with rough a little developed rough endoplasmic reticulum(RER) and golgi apparatus(GA). In 7-, 17 and 27-days old rats, most of the fibroblast showed well developed GA and RER with widely distended cisternae containing granular materials. In many of these cells contained intracytoplasmic filaments among the cytoplamic organelle. In 55-day and 1-year old rats, three types of cells were observed, ie, cells containing well developed cytoplasmic organelle presumed to be involved in the collagen fibril synthesis, cells showing well developed lysosomes, golgi apparatus, mitochondria and short cytoplasmic process presumed to be involved in the active resorption of the injured collagen fibrils or cellular debris, cells containing many intracytoplasmic filaments and a little organelle presumed to be cells of inactive state. The average diameters of collagen fibrils were similar in 1- and 7-day old rats as $38.48{\pm}3.81nm$, $38.06{\pm}3.86nm$. That was thickest in 14 days old rats as $50.21{\pm}3.93nm$ among experimental groups. They were gradually thinner in 27-, 55-day rats as $40.05{\pm}2.52nm$, $43.63{\pm}1.20nm$ and thinnest in 1-year old rats as $37.38{\pm}2.17nm$. The distribution pattern of diameters of collagen fibrils were unimordal with peak of 30-60nm in rats from 1-day to 17-day old. With aging from 27-day to 1 year old rats, collagen fibril diameters showed wide distribution pattern and percentage of thin collagen fibrils increased. These results may show the functional adaptation of fibrous layer of mandibular condyle to the increased mechanical forces with aging.

화학적 발암화에 따른 Protein Kinase C의 발현 변화

변기정,홍락원,김진수 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.4

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 Ca2+-dependent classical isoform and steroid hormone enhances PKC activation. Among cPKC isoforms examined, only PKC-α and r showed significant translocation of protein levels from cytosolic fraction to membrane fraction, as analyzed by immunoblot. PKC-ε 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 treat-ment. The study demonstrated that there was a certain specificity in the patterns of isoform induc-tion 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 cances including oral cancer.

하악골 골절선상의 치아와 관련된 합병증 이환율

卞基禎,卞鍾秀 慶北大學校 齒科大學 1984 慶北齒大論文集 Vol.1 No.2

Complications related to teeth in the lines of mandibular fractures were studied in a retrospective review of 172 fractures. 19 Fractures(11.0%) resulted in some form of morbidity out of 172 fractures. Statistically this study made no difference in this group of 130 patients, but morbidity was slightly greater with fractures in which the teeth were removed before or at reduction.

구강저에 발생한 유피낭종

변기정(Ki Jeong Byeon),이기호(Ki Ho Lee),김진수(Chin Soo Kim) 대한구강악안면외과학회 1999 대한구강악안면외과학회지 Vol.25 No.1

Dermoid cyst has evolved to represent any cyst filled with sebumlike material and with evidence of specialized skin derivatives from defective embryonic development. Approximately 7% of all dermoid cyst arise in the head and neck region and 0.01% of all oral cysts. The anterior region of the floor of the mouth is the most common site of occurrence in the oral cavity. There is no sex predilection and the age at presentation is usually in the second or third decades. Clinically, the lesions present as a rubbery or doughy mass that may vary in size from a few millimeters to 12 ㎝. An intraoral dermoid cyst usually presents as a slowly growing, painless swelling in the anterior floor of the mouth which may eventually cause elevation and displacement of the tongue resulting in dysphonia, dysphonia and dyspnea. Treatment involves surgical removal and recurrences have not been reported. We report three cases of dermoid cyst that were cared successfully in the department of dentistry, Kyung-pook National University. One case is a sublingual type, another case is a geniohyoid type, and the other is a lateral type. 저자등은 구강저에 발생한 3 증례의 유피낭종 및 유표피낭종을 악설골근을 기준으로 존재하는 위치에 따라 구내 및 구외접근법을 통한 외과적 적출을 시행하여 다른 합병증없이 양호한 결과를 얻었기에 보고하는 바이다.

국가청정생산지원센터(KNCPC) 현황

변기정(Gee-Jeung Byun),권몽주(Mong Joo Kwon) Korean Society for Precision Engineering 2003 한국정밀공학회지 Vol.20 No.8

흰쥐의 발치와 재상피화에 따른 상피내 CGRP 면역양성 신경섬유의 분포변화

변기정(Ki Jeong Byeon),김진수(Chin Soo Kim) 대한구강악안면외과학회 2000 대한구강악안면외과학회지 Vol.26 No.4

The purpose of this study was to investigate the distribution pattern of CGRP immunoreactive nerve fibers in the healing mucosa of extracion wound. Maxillary 1st molars of rats were extracted. All extraction sites and adjacent tissues of 3 groups of rats(1-week, 2-week and 4-week groups) were removed en bloc and processed for immunostaining and were subjected to light microscopic examination. The results obtained were as follows; In 1-week group, there was no difference in the distribution pattern of CGRP immunoreactive nerve fiber between epithelial margin adjacent to extraction socket and normal gingival epithelium. In 2-week group, some CGRP-immunoreactive nerve fibers were seen in epithelial layer. In 4-week group, many intercellular CGRP immunoreactive nerve fibers were abundant in all layers of immature epithelium characterized by scab on the mucosa and thick keratinized cell layer with irregular surface. Intraepithelial CGRP immunoreactive nerve fibers were reduced to normal level in adjacent mature epithelium. These results suggest that density of CGRP immunoreactive nerve fibers are increased transiently in epithelium during reepithelialization process and CGRP released from these nerve fibers may play an important role in the reepithelialization in the wound healing.

Pierre Robin 症候群의 一例

卞基禎(Ki Jeong Byeun) 대한치과의사협회 1977 대한치과의사협회지 Vol.15 No.8

해양공간계획 적용을 통한 해상교통관제구역의 효율적 관리 방안

강윤호, 정중식, 김주성, 심재호, 변기정 한국항해항만학회 2014 한국항해항만학회 학술대회논문집 Vol.2014 No.춘계

해상교통관제(VTS, Vessel Traffic Service)는 초창기 정보 전달 역할에서 최근에 선박의사결정지원과 정보통신기술이 결합된 e-Navigation의 중심축으로 그 역할이 확대 되고 있다. 관제 구역은 선박이 항해하는 항로, 정박지, 준설구역, 급유작업, 수상레져 활동, 낚시등 다양한 해양 활동이 동시에 이뤄지고 있다. 따라서 발전하는 관제센터의 역할에 발맞춰 관제 구역에도 해양공간계획(MSP, Marine Spatial Planning) 개념을 도입하여 구역에 대한 관리를 강화해 나갈 필요가 있다. 본 연구에서는 해양공간계획을 도입한 선행 연구 사례를 검토하고 이를 우리나라 해상교통관제에 적용하기 위한 제안을 하고자 한다.