Orthodontic Tooth Movement in the Osteoporotic Rat Maxilla by Local Application of Human Parathyroid Hormone

허현아,박수현,Hyun-Sun LEE,이원,Hyun Joon Yoon,표성운 대한통합치과학회 2021 대한통합치과학회지 Vol.10 No.2

This study aimed to investigate the effect of parathyroid hormone (PTH) on tooth movement in an osteoporotic rat by comparing of the tooth movement distances and histologic observation. Fifteen, 8-week-old female rats were classified into three groups (n=5, respectively): (1) sham-operated control group, (2) ovariectomized group (OVX), and (3) ovariectomized rats injected with 30 μg/kg of PTH group (PTH). To induce the orthodontic tooth movement, a closedcoil spring appliance was placed and activated with the continuous force of 50 cN to the maxillary first molar. During the experimental period, the amount of tooth movement was measured at 7, 14, 21 days and all rats were sacrificed for histologic specimen preparation. The OVX group showed the fastest tooth movement, and the distance of tooth movement in the OVX group was significantly greater than that in the other two groups at 14 and 21 days (P=0.00 and P=0.02, respectively). The histologic sections revealed the evidence of osteopenia in both the OVX and PTH than the control group. And there was tendency to enhanced bone turnover in the inter-radicular bone of the PTH group. In summary, PTH treatment did not promote tooth movement in the osteoporotic rat model but showed the increased bone turnover. Therefore, further study is required to consider the clinical application of PTH during orthodontic treatment.

심부경부감염으로 진행되는 치성감염의 중증도 평가

허현아 대한치과의사협회 2021 대한치과의사협회지 Vol.60 No.1

Uncontrolled odontogenic infections can lead to deep neck infection. Once it progresses to deep spaces of the neck, it can be life-threatening. Therefore, prompt recognition and effective management is mandatory. The aim of this study was to introduce the criteria for evaluating the severity of infection and deciding hospitalization which enables clinicians to effectively manage patients and furthermore to save lives.

Tooth Loss and Long-term Clinical Outcomes in Kidney Transplantation Recipients

허현아,박수현,윤현중,표성운 대한통합치과학회 2023 대한통합치과학회지 Vol.12 No.1

Tooth loss is considered as a representative index of poor oral health. The aim of this study was to identify clinical outcomes following kidney transplantation in relation with the number of tooth loss. Clinical data from 978 patients receiving kidney transplantation between 2010 and 2020 in a single cohort was investigated. Groups were divided according to number of tooth loss (0 to 4, 5 to 9, over 10). Retrospective study was performed by univariate and multivariate logistic statistical analysis for association of clinical variables, recipient’s kidney function, acute rejection episode after kidney transplantation and death with the number of tooth loss. The age, gender, body mass index, accompanying comorbidities, preoperative laboratory values and immunosuppressive regimens were not related with the number of tooth group. No significant association was found between the number of tooth loss and kidney function and risk of rejection after kidney transplantation. However, tooth loss was positively associated with patient survival who had more than 10 teeth lost (HR 26.268, 95% CI 3.506-196.82, P<0.001). There was no direct evidence that poor oral health could worsen the clinical outcome of kidney transplantation. However, the status of tooth loss might jeopardize the survival of kidney transplantation recipients. The participation of oral health care providers in the transplantation team is recommended.

엔드밀 마멸에 따른 절삭력과 표면조도의 특성

허현,이기용,강명창,김정석,황경현 한국생산제조학회 1996 한국공작기계학회 추계학술대회논문집 Vol.1996 No.-

Parylene 버퍼층 구조 $H:LiNbO_3$ 광변조기 제작

허현,김희주,강동성,반재경,Huh, Hyun,Kim, Hee-Ju,Kang, Dong-Sung,Pan, Jae-Kyung 대한전자공학회 1999 電子工學會論文誌, D Vol.d36 No.3

재현성 있는 H:LiNbO\sub 3\ 광변조기의 제작을 위해 기존 광변조기에서 사용되는 Au/Cr/SiO\sub 2\ 전극구조 대신 상온에서 버퍼층 및 전극공정이 가능하고, 광대역 설계에도 유리하도록 새로운 Cu/parylene 전극구조를 사용한 광변조기의 설계 및 제작을 수행하였다. 이를 위해 유한요소법을 이용한 광변조기의 해석 및 설계, 소자제작을 위한 저손실 1550m H:LiNbO\sub 3\ 광도파로 공정, parylene 박막증착 및 CPW 전극형성 등의 단위 공정들을 확립하였다. 이러한 소자설계 기술 및 단위공정들의 결합을 통해 parylene 버퍼층구조 H:LiNbO\sub 3\ 광변조기 내부칩을 제작하였고, 저주파 구동특성 측정시스템을 통해 변조특성을 확인하였다. 특히 Cu/parylene 전극공정 전·후의 광도파로 특성이 일정하게 유지됨으로서 재현성 있는 소자제작이 가능함을 알 수 있었다. $H:LiNbO_3$ optical modulator with Cu/parylene electrode layer, which has a merits in the bandwidth, power consumption and fabrication conditions as compared with conventional Au/Cr/$SiO_2$, is proposed and fabricated. Analysis and design of optical modulator is performed by finite element calculation. Various unit processes for fabricating the proposed modulator, 1550nm $H:LiNbO_3$ optical waveguide, parylene buffer layer, and CPW Cu electrode, were developed, After dicing and end-face polishing of fabricated modulator chip, optical modulation responses as sawtooth electrical driving voltage has been measured at low frequencies. Properties of optical waveguide had not been changed before and after Cu/parylene electrode processes, which make confirm the reproducible fabrication of optical modulator.

직선패턴 인식을 위한 새로운 광/디지틀 불변 인식에 관한 연구

허현,정동규,강동성,반재경,Huh, Hyun,Jung, Dong-Gyu,Kang, Dong-Seung,Pan, Jae-Kyung 대한전자공학회 1994 전자공학회논문지-B Vol.b31 No.11

본 논문에서는 직선특징을 포함한 2차원 패턴에 대하여 패턴의 이동, 회전, 크기변화에도 불변하게 인식할 수 있는 새로운 광/디지틀 패턴인식 방법을 제안하였다. 제시한 방법은 먼저 패턴의 직선특징을 Hough변환과 threshold과정을 통해서 추출한다. 두 번째로 추추된 특징에 본 논문에서 유도된 수식을 적용하여 불변성을 부여한다. 마지막으로 추출된 패턴의 불변특징을 신경회로망으로 학습시켜 패턴인식에 사용하였다. 제시한 방법의 유용성 확인을 위해 9개의 2차원 직선패턴으로 컴퓨터 모의실험을 수행하였으며, 결국 패턴의 이동, 회전, 크기변화에도 불변한 인식이 가능하였다. A novel opto-digital pattern recognition method which has shift, rotation, and scale invariant properties is proposed for recognizing two dimensional images having straight lines. The algorithm is composed of three stages. In the first stage the line features of the image are extracted. The second stage imposes the shift, rotation, and scale invariant properties on the extracted features through normalizing procedure. The required normalizing equations are analytically explained. In the last stage, the artificial feedforward neural network is trained with the extracted features. In order to evaluated the proposed algorithm, nine different edge enhnaced binary images composed of straight lines are tested. Thus the proposed algorithm can recognize the patterns event though they are shifted, rotated, and scaled.

H:LiNbO$_{3}$ 광변조기에서 Parylene 버퍼층의 유용성

허현,반재경,Huh, Hyun,Pan, Jae-Kyung 대한전자공학회 1997 電子工學會論文誌, D Vol.d34 No.8

H:LiNbO$_{3}$ optical modulator buffered by parylene layer, which has a merits in the bandwidth, power consumption and fabrication as compared with conventional SiO$_{2}$ buffered optical modulator, is proposed and analyzed. The dependences of velocity matching condition, charcteristics impedance, and driving voltage on dielectric constants, thickness of buffer layer, and electrode configurations are demonstrated with finite element calculation. And we performed the physical and chemical test of parylene buffer layer deposited on LiNbO$_{3}$ and under Au electrodes.

측정용 전리함에 따른 고 선량율 근접치료용 방사성 선원의 겉보기 활성도의 정확도 비교 분석

허현도,최진호,최상현,김성훈,김우철,김헌정,이레나,김금배,홍성언,신동오,Huh, Hyun-Do,Choi, Jin-Ho,Choi, Sang-Hyoun,Kim, Seong-Hoon,Kim, Woo-Chul,Kim, Hun-Jeong,Lee, Re-Na,Kim, Kum-Bae,Hong, Seong-Eon,Shin, Dong-Oh 한국의학물리학회 2008 의학물리 Vol.19 No.4

The aim of this study is to introduce the accuracy of Ir-192 source's apparent activity using the well-type chamber and the Farmer-type ionization chamber in the high dose rate brachytherapy. We measured the apparent activity of Ir-192 that each medical center in the country has and the apparent activity of calibration certificate provided by manufacturer is compared with that by our experimental measurement. The number of sources used for the activity comparison was 5. The accuracy of the measured activity was in the range of -2.8% to -1.0% and -2.1% to 0.2% for the Farmer-type chamber system (Jig) and for the well-type, respectively. The maximum difference was within 1.0% for comparison with two calibration's tool. Our results demonstrate that well-type chamber as wall as Farmer-type chamber is a appropriate system as the routine source calibration procedures in HDR brachytherapy. Whenever a new source is installed to use in clinics, by periods, a source calibration should be carried out. 본 연구에서는 측정 방법이 다른 두 전리함을 이용하여 고선량율 근접치료용 방사성 선원의 겉보기 활성도를 측정하여 선원의 활성도 정확성 및 두 장비간의 정확도를 비교 분석하였다. 국내 5개 의료기관을 선정하여 공기 중 기준거리에서 겉보기 활성도를 측정하고 동일한 선원에 대하여 측정 방법이 다른 두 팬톰을 동시에 측정하여 측정방법에 따른 상호 오차와 측정용 전리함의 정확도를 평가하였다. 우물형 전리함과 Jig 팬톰의 상대 오차는 각각 -2.1%~0.2%, -2.8%~-1.0%로 나타났다. 동일한 방사성선원에 대하여 두 교정 장비간의 정확도 평가는 최대 상대오차 1%로 나타났다. 선원의 세기 검증 시 측정 방법에 따른 의존도는 없었다. 고 선량율 근접방사선치료에 사용되는 방사성 선원의 세기의 변화는 환자의 종양 및 인접장기에 미치는 영향이 매우 크므로 방사성 선원의 세기 오차는 환자치료의 최적화에 심각한 영향을 미칠 수 있다. 그러므로 새로운 선원 교체 시 뿐만 아니라 주기적인 선원 점검이 요구된다.

생진양혈탕(生津養血湯) 물 추출물의 Streptozotocin 유발 고지혈증에 대한 효과

허현,김대준,변준석,최빈혜,Hur, Hyun,Kim, Dae-Jun,Byun, Joon-Seok,Choi, Bin-Hye 대한한방내과학회 2006 大韓韓方內科學會誌 Vol.27 No.2

In the Present study, the therapeutic hypolipemic effect of water extract of Saengjinyanghyl-tang (SJYHT), a herbal extract mixture for treatment of diabetes in oriental medicine was tested in Streptozotocin-induced diabetic hyperlipemic SD rats. For detect the therapeutic effects, the test articles were once a day dosed for 28 days by gastric gavage at a dosage 1000, 500 and 250mg/kg from 25 days after STZ-dosing, and the changes on body weight and gains, serum LDL, HDL, Triglyceride and Total Cholesterol levels were observed In addition, the effects of test articles were compared to that of Simvastatin, a well known hypolipemic agents 10mg/kg-dosing group. Base on these results, although no meaningful effects were detected on the serum HDL levels, it is concluded that Saengjinyanghyul-tang water extracts have relatively good favorable effect treatment of STZ-induced diabetic hyperlipemia because they showed clear evidences inhibit the increase of serum LDL, Triglyceride and Total Cholesterol levels. Therefore, it is expected that Saengjinyanghyul-tang extract has favorable potency to development hypolipemic drugs. In addition, about 1000mg/kg of Saengjinyanghyul-tang extracts have similar effect compared to that of Simvastatin 10mg/kg. The effective dosage of Saengjinyanghyul-tang water extracts in the present study was considered as below 250mg/kg.

새로운 자유의 탄생? : 미국 내전의 신화와 미완의 제2차 혁명전쟁

허현 강원사학회 2020 江原史學 Vol.0 No.35

The Civil War remains a myth of Abraham Lincoln’s emancipation narrative in the American history. Especially, the Gettysburg Address that declared “a new birth freedom” was considered a historical moment in which Lincoln defined the Civil War as the abolition war. As Eric Foner argues, the Civil War could be defined as a revolutionary war in that it made “the Second Founding” through the constitutional revolution. However, labelling the Civil War only as a moral victory or as a “the Second Founding” restrains from understanding what the Civil War really was. In fact, the Civil War started as a the Confederate’s war to defend slavery. And Lincoln’s war against secession was not a emancipation narrative but reunion narrative or democracy narrative. Northerners also regarded the war as “the white men’s war” or “the brothers’ war,” consistently avoiding the transformation of the meaning of the Civil War into a social revolution. However, blacks’ struggles for freedom during the war turned the war into a ‘revolution’ in the end. As a result, Lincoln confessed in the Second Inaugural that slavery was the major cause of the Civil War from the start. But, the Confederates transformed the war for the slavery into the war for the states’ rights and democracy against the centralized federal government after their defeat. Using the ideology of “the Lost Cause,” the Confederates defended their war as moral and liberal, pretending that secession had nothing to do with slavery and race. This fabricated history enabled the Confederates’ honorable re-incorporation into the American history. Then, it is said that the Civil War remains another myth of the Confederates’ liberation narrative as well as that of Lincoln’s emancipation narrative. Unlessthe Civil War considered an unfinished revolution for universal freedom and human equality, there is no truth in the historical narrative of the Civil War. 미국 내전은 미국 역사에서 일종의 신화적 드라마로 남아있는 전쟁이다. 많은역사가들은 특히 “새로운 자유의 탄생”을 선언했던 당시 미합중국 대통령 링컨의게티즈버그 연설이 내전을 해방 서사로 묘사하면서 노예제 폐지를 위한 위대한혁명전쟁으로서 규정하는 데 결정적인 역할을 했다고 평가한다. 에릭 포너(Eric Foner)가 주장하듯 미국 내전이 헌법적 혁명을 통해 ‘제2의 건국’에 해당하는 역사적 국면을 열어젖혔다는 점에서 내전을 해방 서사라 규정할 수도 있겠지만 이렇게내전을 일종의 도덕적 승리의 드라마이자 재건국의 장(場)으로서만 바라보는 것은내전의 역사적 실체를 제대로 파악하지 못하게 만들어 결과적으로 내전을 탈역사화하는 우(愚)를 범할 수밖에 없다. 실제로 미국 내전은 애초에 노예제를 폐지하기 위한 혁명전쟁이 아니라 노예제를사수하기 위한 남부연합 세력의 반(反)혁명전쟁으로 시작되었고 더구나 이러한 남부연합 세력의 반(反)혁명전쟁에 맞서 써내려갔던 대통령 링컨의 서사는 결코 해방서사가 아니라 연방 수복의 서사, 연방분리주의 분쇄의 서사, 그리고 민주주의 원리의 수호 서사였다. 링컨뿐만 아니라 북부인들의 내전에 대한 일반적인 인식도 흑인노예들 및 노예제와 관련성을 적극적으로 부정하는 “백인들의 전쟁”이요 “형제들의전쟁”일 뿐이었다. 이들은 내전이 인종질서의 붕괴를 야기하는 급진적인 사회혁명으로 전화하는 것에 대해 늘 경계와 우려의 시선을 거두지 않았다. 하지만 자유를위한 흑인들의 투쟁은 기어코 내전을 ‘혁명’으로 만들어버렸고 링컨은 마침내 전쟁에서 승리하는 유일한 길은 내전을 노예제 폐지를 위한 혁명전쟁으로 만드는 것뿐이라는 사실을 깨달았다. 그러나 반란을 일으켰던 남부연합 세력은 전쟁이 ‘혁명’이되어 노예해방전쟁으로 역사화되어 가던 바로 그 시점에 내전의 의미를 재규정하여노예제 사수를 위한 전쟁이 아니라 주권(州權)과 민주주의의 수호를 위한 전쟁으로만들어버렸다. 남부 노예제세력은 패전과 더불어 노예제 사수를 위한 반란의 기억을철저히 지워버리고 중앙집권적인 연방정부의 압제에 맞서 주권 수호와 민주주의를위해 분연히 떨쳐 일어난 허구적인 해방 투쟁의 역사를 만들기 시작했다. 이렇게날조된 전쟁의 역사는 남부인들에게 “좌절된 대의(the Lost Cause)”로 남게 되었고미국 역사에 다시 명예롭게 편입할 명분이 되어버렸다. 그렇다면 결국 미국 내전은 또 다른 의미에서 신화적 드라마로 남아있는 전쟁이라고 할 수 있다. 링컨의 해방 서사로서가 아닌 남부연합 세력의 해방 서사로서 말이다. 내전이 그 누구, 어떤 세력의 해방 서사가 아닌 미완의 혁명으로 설명되지 않는한 미국 내전의 역사 속에는 링컨의 본 모습도, 남부연합의 진실도, 결연한 흑인들의혁명 서사도 존재할 수 없다.