• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.37.1-37.7
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• 2018

Background: Fibrous dysplasia (FD) is characterized by the replacement of normal bone by abnormal fibro-osseous connective tissue and typically treated with surgical contouring of the dysplastic bone. When dysplastic lesions involve occlusion, not only is surgical debulking needed, orthognathic surgery for correction of dentofacial deformity is mandatory. However, the long-term stability of osteotomized, dysplastic bone segments is a major concern because of insufficient screw-to-bone engagement during surgery and the risk of FD lesion re-growth. Case presentation: This case report reviewed two patients with non-syndromic FD that presented with maxillary occlusal canting and facial asymmetry. Le Fort I osteotomy with recontouring of the dysplastic zygomaticomaxillary region had been performed. The stability of osseous segments were favorable. However, dysplastic, newly formed bone covered the previous plate fixation site and mild bony expansion was observed, which did not influence the facial profile. Including the current cases, 15 cases of orthognathic surgery for FD with dentition have been reported in the literature. Conclusion: The results showed that osteotomy did not appear to significantly reduce the long-term stability of the initial fixation insufficiency of the screw to the dysplastic bone. However, based on our results and those of the others, long-term follow-up and monitoring are needed, even in cases where the osteotomized segment shows stable results.

• 한국항공우주학회지
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• 제36권6호
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• pp.587-593
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• 2008

본 연구의 목적은 신체 조직의 손상을 최소화할 수 있는 경피(transdermal) 및 국부적인(topical) 약물전달을 가능하게 하는 마이크로 입자가속시스템 개발에 있다. Ballistic 역학을 기반으로 하는 본 방법을 통하여 체순환을 위한 경피 및 국부적 약물 전달이 가능하다. 얇은 금속 포일의 한 쪽 면에 마이크로 입자들을 얹어놓고 뒷면에 레이저를 조사하면 충격파가 발생하고, 이 충격파는 포일을 통과하며 포일의 끝에서 금속-공기간의 acoustic impedance 차이로 expansion wave로 반사되어 포일이 반대 방향으로 변형을 일으키게 한다. 이 순간적인 변형으로 인해 포일에 붙어있던 마이크로 입자들이 가속되어 튕겨 나가게 된다. 입자들이 가속되는 속도가 굉장히 크기 때문에 이들은 신체 조직을 침투할 만한 충분한 운동량을 갖고 있다. 입자들의 침투 여부를 확인하기 위해 우리는 5${\mu}m$ 크기의 코발트 입자들을 연조직을 묘사하는 젤라틴에 가속시켰으며, 주목할 만한 침투 깊이를 얻으며 실험에 성공하였다.

• 한국발생생물학회지:발생과생식
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• 제23권3호
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• pp.213-221
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• 2019

The epididymal fat of mouse is a part of visceral fat deposit and is divided into the distal or proximal part based on its histochemical characteristics. Even though the formation of the epididymal fat pad begins before the birth, a detailed adipogenic procedure of the epididymal fat has not been revealed. The epididymal fat pad becomes enlarged and expended with age, and expressional changes of numerous genes are associated with the maturation of fat tissues. In the present research, expressional patterns of adipose tissue-related genes in the distal epididymal fat of mouse at 2, 5, 8, and 12 months of postnatal age were determined by a quantitative real-time polymerase chain reaction (PCR) analysis. The lowest transcript levels of fatty acid binding protein 4 (Fabp4), lipoprotein lipase (Lpl), delta like non-canonical Notch ligand 1 (Dlk1), peroxisome proliferator-activated receptor gamma (Pparg), leptin (Lep), adiponectin (Adipoq), and resistin (Retn) were detected at 2 months of age, except fatty acid synthase (Fasn) showing the lowest level at 5 months of age. Even though expression of Lep and Fabp4 were gradually increased until 12 months of age, significant increases of Pparg and Adipoq transcript levels were continued until 8 months of age. The transcript levels of Lpl, Rent, Dlk1, and Fasn were significantly increased at 8 months of age, compared with those at 2 months of age. The current findings suggest that the expansion of the distal epididymal fat of mouse during postnatal period would be companied with differential expression of various adipocyte-associated molecules.

• 대한금속재료학회지
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• 제48권4호
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• pp.369-375
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• 2010

Ti-6Al-4V ELI alloy, which is commonly used as a biomaterial, is associated with a high elastic modulus and poor biocompatibility. This alloy presents a variety of problems on several areas. Therefore, the development of good non-toxic biocompatible biomaterials with a low elastic modulus is necessary. Particularly, hydroxyapatite (HA) is an attractive material for human tissue implantation. This material is widely used as artificial bone due to its good biocompatibility and similar composition to human bone. Many scientists have studied the fabrication of HA as a biomaterial. However, applications of bulk HA compact are hindered by the low strength of HA when it is sintered. Therefore, HA has been coated on Ti or Ti alloy to facilitate good bonding between tissue and the HA surface. However, there are many problems when doing this, such as the low bonding strength between HA and Ti due to the different thermal expansion coefficients and mechanical properties. In this study, a Ti-HA composite with a porous surface was successfully fabricated by pulse current activated sintering (PCAS) and a subsequent leaching process.

• Journal of Food and Nutrition Research
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• 제9권3호
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• pp.163-169
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• 2021

Decreased adipocyte fatty acid oxidation (FAO) and impaired preadipocyte differentiation characterize hypertrophic expansion of adipose tissue (AT) from obese and insulin resistant humans and are recognized as potential mechanisms for obesity-mediated dyslipidemia. Supplementation of formononetin (FMN), one of the principal isoflavones extracted from red clover or Huangqi (Astragalus roots), has been shown to have beneficial effects on obesity-related hyperlipidemia, a well-established cardiovascular risk factor. However, a target tissue and underlying mechanism(s) through which FMN acts have been under-investigated. Thus, we investigated whether FMN promotes adipocyte FAO and preadipocyte differentiation using 3T3-L1 preadipocytes to provide potential mechanisms of FMN action. We further extended this to the culture of 10T1/2 mesenchymal stem cells (MSCs) as well as mouse AT explants to reflect in vivo effects of FMN. In fully differentiated 3T3-L1 adipocytes, FMN-treatment significantly increased the expression levels of FAO-related proteins such as pAMPK, pACC, and CPT1, all of which were consistently upregulated in AT explant cultures treated with 10 μM FMN. In addition, FMN significantly enhanced the degree of differentiation of both 3T3-L1 preadipocytes and 10T1/2 MSCs into adipocytes as evidenced by Oil Red O staining of cellular lipids. This observation correlated with increased expression levels of key adipogenic transcription factors (PPARγ and C/EBPα) and their down-stream target proteins (FABP4, Glut4 and adiponectin). Moreover, FMN failed to exert its stimulatory effects on preadipocyte differentiation in both cell types in the presence of a PPARγ antagonist, suggesting a PPARγ-dependent effect of FMN. Collectively, these data provide possible mechanisms of action of FMN on lipid metabolism and further support the favorable in vivo effects of FMN in diet and obesity-induced dyslipidemia.

• 대한치과교정학회지
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• 제32권5호
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• pp.313-325
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• 2002

3차원 CT에서는 환자의 움직임에 의한 오차와 상의 확대나 왜곡을 감소시킨 실측치를 얻을 수 있으며 두개안면부의 입체적인 영상을 구성할 수 있고 원하는 조직이나 구조물의 관찰이 용이하다 디지털 영상 기술이 빠르게 발전하고 있고 치료의 범위가 더욱 넓어지면서 두개악안면 구조의 3차원적인 분석법의 개발은 시급한 과제가 되었다. 이에 본 연구에서는 Vworks 프로그램$^{TM}$ (Cybermed Inc., Seoul, Korea)과 건조두개골을 이용하여 3차원 CT 영상의 오차와 확대율을 평가하고Vmorph-proto프로그램 $^{TM}$ (Cybermed Inc., Seoul, Korea)을 이용하여 정상인과 비대칭 환자의 3차원 CT영상에서 지정이 용이하고 반복재현성이 높은 계측점을 설정하고자 하여 다음과 같은 결론을 얻었다 ; 1. 건조두개골의 실측치와 Vworks 프로그램을 이용하여 구성한 3차원 CT영상에서 의 계측치를 비교한 결과 평균오차가 0.99mm, 확대율이 1.04%로 나타났다. 2. 3차원 CT영상에서 경조직 계측점으로 Supraorbitale, Lateral orbital margin, Infraorbitale, Natron, ANS, A point, Zygomaticomaxilla, Upper incisor, Lower incisor, B point, Pogonion, Menton, PNS, Condylar inner margin, Condylar outer margin, Porion, Condylion, Gonionl, Gonion2, Gonion3, Sigmoid notch, Basion 등이 임상적으로 유용하다고 판단되었다. 3. 3차원 CT영상에서 연조직 계측점으로 Endocanthion, Exocanthion, Soft tissue Nasion, Pronasale, Alare lateralis, Upper nostril point, Lower nostril point, Subnasale, Upper lip point, Cheilion, Stomion, Lower lip center, Soft tissue B, Pogonion, Menton, Preaurale 등이 임상적으로 유용하다고 판단되었다. Vworks 프로그램으로 3차원 CT영상을 구성하고 계측하는 것이 임상적으로 유용하다고 판단되었다. 또한 위에서 제안된 연조직 및 경조직 계측점들은 3차원 CT영상에서 반복 재현성이 높고 지정이 용이하며 해부학적 특징을 나타내주는 점들로 두개악안면 구조의 3차원적인 진단과 술전, 술후의 예측과 비교에 유용하게 사용될 것으로 사료되는 바이다.

• Imaging Science in Dentistry
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• 제32권3호
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• pp.167-173
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• 2002

Purpose : To evaluate clinical and radiographic differential diagnosis between ameloblastoma and odontogenic keratocyst (OKC) using clinical data, plain radiographs, and CT. Materials and Methods: 25 cases of ameloblastoma and 44 cases of OKC diagnosed in biopsy, were selected from the files stored in Department of Oral and Maxillofacial Radiology, Seoul National University Dental Hospital from 1999 to 2001, and evaluated using following criteria: sex and age, location, shape, border to normal bone tissue, effect to adjacent tissues, homogeneity in the lumen of the lesion, response of the cortical bone, long-to-short length (LIS) ratio of the lesion, and expansion angle of the cortex. Results: Ameloblastoma and OKC were seen most frequently in third decades and no statistical significance was noted between both sexes. Ameloblastoma occurred most frequently in mandibular angle and ramus area (68%) and OKC at the maxillary molar (34.1 %), and mandibular angle and ramus area (43.2%). The root resorption of the adjacent teeth, mandibular canal displacement, and the impaction of teeth were seen more frequently in ameloblastoma than in OKC. The LIS ratio measured in CT was largest in maxillary OKC cases, followed by mandibular ameloblastoma, and mandibular OKC (1.2, 1.8 and 2.4 respectively). The expansion angle of the cortex shows a statistically significant difference between ameloblastoma (48.8°) and OKC (31.5°). Conclusion : The numeric morphology (LIS ratio) and expansion angle of the cortical bone of the lesion measured in computed tomography can be used to differentiate the ameloblastoma and odontogenic keratocyst.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권6호
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• pp.649-652
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• 2008

Osteoblastoma is a relatively rare benign bone tumor representing less than 1% of all bone tumors. The tumor usually involves the spine and sacrum of young individuals, less than 10% being localized to the skull, and nearly half of these affect the mandible, especially the posterior segments. In clinical finding, osteoblastoma present mainly with pain, swelling, and expansion of bone cortex. Radiographic appearances are variable, but frequently a well-delineated radiolucent lesion containing varying amounts of mineral deposits is seen. Histologically, ostoeblastoma is consists of irregular trabeculeae of osteoid and immature bone present within highly vascular connective tissue matrix. Osteoblastoma must be differentiated from a number of bone-producing lesions, including osteoid osteoma, fibrous dysplasia, ossifying fibroma, fibrous dysplasia, and osteosarcoma. If diagnosis may be mistaken for osteosarcoma, there are risks of more aggressive and irreversible treatment. Differential diagnosis of osteoblastoma is important. The preferred treatment of osteoblastoma is conservative approach and surgical excision. Recurrence following surgical intervention is rare. We treated osteoblastoma located in premolar area of mandible by excision with preservation of vital structure, such as nerves and teeth. So we report our clinical treatment with literature review

• 대한소아치과학회지
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• 제26권1호
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• pp.119-125
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• 1999

Air turbine handpiece를 사용하여 치간 법랑질을 삭제하는 Air-rotor stripping 술식은 악궁확장이나 발치 술식에 대한 대체방안으로써 arch length discrepancy를 해결할 수 있는 효과적인 접근법으로 사료된다.

• 식물조직배양학회지
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• 제27권4호
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• pp.269-282
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• 2000

Benzylisoquinoline alkaloids are a diverse group of natural products that include many pharmacologically active compounds produced in a limited number of plant families. Despite their complexity, intensive biochemical research has extended our knowledge of the chemistry and enzymology of many important benzylisoquinoline alkaloid pathways, such as those leading to the analgesic drugs morphine and codeine, and the antibiotics sanguinarine and berberine. The use of cultured plant cells as an experimental system has facilitated the identification and characterization of more than 30 benzylisoquinoline alkaloid biosynthetic enzymes, and the molecular cloning of the genes that encode at least 8 of these enzymes. The recent expansion of biochemical and molecular technologies has creat-ed unique opportunities to dissect the mechanisms involved in the regulation of benzylisoquinoline alkaloid biosynthesis in plants. Research has suggested that product accumulation is controlled by the developmental and inducible regulation of several benzylisoquinoline alkaloid biosynthetic genes, and by the subcellular compartmentation of biosynthetic enzymes and the intracellular localization and trafficking of pathway intermediates. In this paper, we review our current understanding of the biochemistry, cell biology, and molecular regulation of benzylisoquinoline alkaloid biosynthesis in plants. We also summarize our own research activities, especially those related to the establishment of protocols for the genetic transformation of benzylisoquinoline alkaloid-producing species, and the development of metabolic engineering strategies in these plants.