교정용 열가소성 재료의 두께와 변형량이 재료의 물리적 특성에 미치는 영향

민샘,황충주,유형석,이상배,차정열 대한치과교정학회 2010 대한치과교정학회지 Vol.40 No.1

Objective: The purposes of this study were to evaluate the force and stress depending on the type, deflection and thickness of the materials and to evaluate the mechanical properties of thermoplastic materials after repeated loading. Methods: Four types of thermoplastic products were tested. Force until the deflections of 2.0 mm and the stress when the materials were restoring to its resting position were evaluated. The mechanical properties of thermoplastic materials evaluated after 5 repeated loading cycles. Results: The interaction was observed between the thickness and the deflection (p < 0.05) from the regression equation. Thickness and amount of deflection rather than products and materials showed the largest effect on force and stress. In all products, at least 159 gf of force was required for more than 1.0 mm deflection or when materials with 1.0 mm thickness were deflected. The stress recorded was more than 19 gf/mm². During repeated loading, each group showed significant difference on the force and the stress (p < 0.01), 10 - 17% reduction of force and 4 - 7% reduction of stress in average. Conclusions: Proper thickness of thermoplastic materials and deflection level of tooth movement should be decided for the physiologic tooth movement. Force decay after repeated loading should be considered for the efficient tooth movement. 다양한 열가소성 교정 재료를 이용한 성공적인 임상 결과가 보고되었지만, 재료의 물리적 성질에 관한 연구는 많지 않다. 본 연구는 열가소성 재료의 종류, 두께, 변형량과 반복변형에 따른 변형 시 필요한 하중과, 변형되었던 재료가 원래의 상태(resting position)로 돌아갈 때 재료의 복원력을 평가하였다. 실험적인 모델의 조건에서 투명교정장치의 재료로 쓰이는 4가지 종류의 열가소성 재료(0.5 mm, 0.75 mm, 1.0 mm 두께)를 최종 변형량이 2.0 mm가 될 때까지의 하중(gf)을 측정하였다. 변형 후 탄성력에 의해 원점으로 회복될 때, 재료의 복원력(gf/mm²)을 측정하였다. 동일한 방법으로 5회 반복변형 동안의 하중과 복원력의 변화를 측정하였다. 그 결과, 열가소성 재료의 두께와 변형량에 대해 상호 교호작용이 관찰되었으며 (p < 0.05), 열가소성 재료의 두께 및 변형량이 하중과 복원력에 가장 큰 영향력을 나타내었고 재료 간 혹은 제품 간의 하중과 복원력에는 유의한 차이가 없었다. 두께가 1.0 mm이거나 또는 1.0 mm 이상 변형인 경우 최소 159 gf의 하중이 필요하였고, 최소 16 gf/mm2의 복원력이 발생하였다. 각 실험군에 대한 반복하중 시 하중과 복원력에서 유의한 차이가 관찰되었고 (p < 0.01), 평균 10 - 17%의 하중 감소와 4 - 7%의 복원력 감소가 관찰되었다. 이상의 결과, 하중과 복원력에 가장 영향을 많이 주는 요소는 재료의 두께와 치아의 이동량 이었다. 제품에 상관없이 두께가 1.0 mm 이상인 재료를 사용하거나 치아를 1.0 mm 이상 이동 시에는 과도한 힘이 발생하였다. 따라서 투명교정장치를 이용하여 생리적으로 치아를 이동시키기 위해서는 초기 치아배열을 위해 사용하는 열가소성 재료의 두께와 셋업 시 치아 이동량을 고려하여 과도한 힘이 가해지지 않도록 해야 한다. 또한 반복하중 후에 열가소성 재료의 피로도에 의한 힘의 상쇄를 고려하여 임상에 적용해야 한다.

뇌종양 수술 후 방사선치료에 의해 발생한 이차성 조증

유범희,우종민,신형진,김승태 大韓神經精神醫學會 1997 신경정신의학 Vol.36 No.5

국소적 대뇌 병변에 의한 이차성 조증은 드물게 보고되어 왔다. 저자들은 정신과적 병력이 없던 사람이 좌측 측두엽 뇌종양의 종양 절제술을 받은 뒤 별다른 문제없이 잘 지내다가 수술 후 방사선치료를 받은지 약 4개월만에 조증 삽화를 보인 증례를 경험하였다. 정위적 조직검사 결과 이는 방사선치료에 의한 후유증으로 지연성 손상이 일어나 우측 해마 부위가 괴사되었기 때문이 것으로 밝혀졌다. 본 증례를 통해 저자들은 이차성 조증의 발병과 우측 해마 부위의 병변이 밀접하게 관련되어 있음을 확인할 수 있었다. 이처럼 이차성 조증과 뇌의 국소적 병변 부위 사이의 관련성을 밝히는 것은 앞으로 일차성 조증의 신경해부학적, 신경생물학적 원인을 규명하는 데에도 크게 기여할 수 있으리라 생각된다. Secondary mania associated with focal brain lesion has only rarely been reported. The authors report a case of secondary mania after postoperative radiation therapy for primary brain tumor. Localized necrotic lesion was found in the right basotemporal lobe involving hippocampus, which might be the result of late delayed damage of the postoperative radiation therapy. This case suggests that secondary mania is closely related to focal, right basotemporal lesions. Knowing the relationship between the location of brain lesions and manic syndrome may be helpful to us in understanding the neuroanatomical and neurobiological mechanism of primary mania.

줄기 세포 분야의 유전자 치료 연구 동향

오유경,정형민 한국약제학회 2002 Journal of Pharmaceutical Investigation Vol.32 No.2

Recently, stem cell-mediated gene therapy is emerging as a novel therapeutic approach. For the successful gene modification of stem cells, the development of a suitable gene transfer technique needs to be preceded. This review focuses on the various gene transfer techniques based on nonviral and viral vectors, and physical methods. The advantages and disadvantages of each gene transfer method are compared, and the general properties of these vectors are discussed in relation to the gene transfer in stem cell research. This review also highlights the therapeutic application of stem cell-mediated gene therapy. The choice of gene transfer vectors may vary depending on the type of the stem cells and the target of stem cell therapy. Of various gene transfer methods, viral vector-based gene therapy has been emphasized due to the higher transfection efficiency. The current status and up-to-date findings of stem cell-mediated gene therapy are discussed in the viewpoint of the various targets of stem cell therapy such as the modification of stem cell potency, the acceleration of regeneration process and the formation of expressional organization.

殺蟲性 結晶蛋白質 特異的인 抗體의 生産

김기윤,이정민,유형진,백길현,권무식 성균관대학교 생명과학자원연구소 1996 生命資源科學硏究 Vol.3 No.1

Bacillus thuringiensis is a gram-positive soil bacterium characterized by its ability to produce crystalline inclusions during sporulation. These parasporal bodies consist of protoxins known as crystal proteins exhibiting highly specific insecticidal activities. The Lepidoptera-specific protoxin, Cry IAc, was purified from E.coli JM103 harboring the cry IAc gene. The gene was isolated from Bacillus thuringiensis kurstaki HD-73 and subcloned into an expression vector, pKK223-3. The recombinant DNA(pOS4201) was transformed into E.coli JM103. The Cry I Ac protoxin overexpressed in the E.coli was isolated from the total proteins by differential solubility. The protoxin were trypsinized to obtain activated toxin. The proteins was resolved on SDS gel. The molecular weights of the pro-and toxin were resistered about 130,000 and 65,000 Daltons respectively. The Cry IAc toxin was used as immunogen to produce anti-Cry IAc antiserum in a rabbit. The immunogen (200㎍/ 200㎕) was mixed with an equal volume of Freund's complete adjuvant, and the mixture was hypodermically injected to the hide back (30 spots) and paws (2 spots) of the rabbit. The immunization was performed four times every two weeks. The dosage of the immunogen was decreased by half, and incomplete adjuvant was substituted for the complete one from the second immunization. The serum was prepared from the blood as described elsewhere. Immunoreactivity of the serum was examined by dot-blotting with the aid of GAR-HRP indirect immunoassay kit. It has been found that the anti-Cry I Ac antiserum recognized nano-gram quantity of antigen under these experimental conditions. The antiserum will he used for the development of immunochemical mean(s) to screen transgenic plants transformed by the insecticidal characteristics of Cry I Ac.

Amylase 特異的인 抗體의 生産

강미란,이정민,유형진,김기윤,권무식 성균관대학교 생명과학자원연구소 1997 生命資源科學硏究 Vol.4 No.1

The advent of immunochemistry expedites the development of a number of important procedures for gene cloning, disease control (diagnosis, treatment) and biochemical analyses in animal systems. These procedures can be applicable to plant systems : immunochemical detection of biopolymers (proteins, carbohydrates, growth hormones, and pathogenic virus particles). It is not quite difficult to purify various palnt immunogens. However, immunochemical screening methods for specific substances of plants are scarce, so that these procedures for each substance are to be developed. During the cereal germination, amylase converts the starchy endosperm of the seed to nutrient that support the growing seedling. α-Amylase and β-amylase hydrolyze internal α-1,4 glycosidic linkages in starch and dextrin. They produce α-maltose and β-maltose respectively. Their gene expression is regulated by gibberellic acid (negative regulator) and abscisic acid (positive regulator). In this study, α-amylase (from barley malt) protein was analyzed with SDS-PAGE. The molecular weight of α-amylase was about 60,000 daltons. α-Amylase protein was used as immunogen to produce antiα-amylase antiserum in a rabbit. The immunogen was mixed with an equal volume of Freund's complete adjuvant, and the mixture was hypodermically injected to the hideback (30 spots) and paws (2 spots) of the rabbit. The immunization was performed with two week interval. The dosage of the immunogen was decreased by half, and incomplete adjuvant was substituted for the complete one from the second immunization. The serum was prepared from the blood, and immunoreactivity of the serum was examined by dot-blotting and western blotting using the GARHRP indirect immunoassay kit. It was found that the anti α-amylase antiserum recognized nano-gram quantity of antigen under these experimental conditions. The antiserum will be used for the development of immunochemical assay to detect the time of the seed germination.

골수 유래 기질 줄기세포의 탐식작용 매개성 케모카인 수용체 발현 연구

정영신,변향민,신지영,김정목,정형민,오유경 한국약제학회 2003 Journal of Pharmaceutical Investigation Vol.33 No.4

To design gene delivery systems which can deliver higher amounts of genes into stem cells, we studied the expression of receptors involved in the receptor-mediated endocytosis of bone marrow stromal stem cells. Bone marrow was isolated from ICR mice, and bone marrow stromal stem cells were isolated based on their plastic adherence property. Several cultrure conditions were screened for effective and continuous culture of marrow stromal stem cells. MesenCult medium was finally used to cultivate marrow stromal stem cells in vitro. As candidate receptors, various chemokine receptors were studied. Both bone marrow cells and marrow-derived stromal stem cells showed expression of CC chemokine receptors (CCR) and CXC chemokine receptors (CXCR). Marrow stromal stem cells showed higher expression of CCR5 and CXCR4 chemokine receptors as compared to other types of chemokine receptors. Moreover, though the expression chemokine receptors generally decreased in most chemokine receptors with the cultivation of marrow stromal stem cells, CCR5 and CXCR4 chemokine receptors retained the higher lever of receptor expressions over prolonged periods. These results suggest that the ligands exhibiting specific binding to CCR5 or CXCR4 might be used to modify gene delivery systems for increased level of receptor-mediated gene delivery into stromal stem cells.

엄지발가락에 발생한 건초 섬유종 1예

이경호,조유경,한예원,김진아,김형민,박철종 대한피부과학회 2006 大韓皮膚科學會誌 Vol.44 No.4

Doppler ultrasound를 이용한 교정적 치아 이동 시 치수 혈류량의 변화의 측정 : 예비실험

임경섭,배영민,차정열,유형석,황충주 대한치과교정학회 2009 대한치과교정학회지 Vol.39 No.6

교정적 치아 이동 시 지속되는 압력에 의해 혈류변화가 발생하게 되며, 이러한 변화양상에 있어서 선학들의 연구 방법 및 그 결과의 다양성이 존재하였다. 본 연구에서는 Doppler ultrasound를 이용하여, 교정치료 전과 교정치료 시작 3주, 6주 후 치수 혈류량의 연속적인 변화를 알아보고자 하였다. 만 15세 이상 환자 18명을 연구대상으로 Doppler ultrasound를 이용하여 상, 하악 6전치 중 경도의 총생(2 mm 미만)을 보이는 치아(총생측정: required space-available space)와 인접치아를 포함한 3개의 치아를 대상으로 치수 혈류량의 변화를 알아보았다. 연구결과 부위별(상, 하악), 치아별, 기간에 따른 치수 혈류량의 변화는 교정 치료 시작 전과 시작 후 3주, 6주 혈류량에 유의한 차이가 없었다. 또한 치수 생활력 상실의 내재적 위험성을 비교하고자 교정 치료 시작 전 치아별로 치수혈류량을 비교하였을 때, 상악에서는 측절치, 하악에서는 견치에서 통계학적으로 유의한 차이는 나타나지 않았지만, 모든 항목에서 적은 값을 나타냈다 (p > 0.05). 본 연구의 결과는 이후에 진행될 Doppler ultrasound의 치아이동유형, 환자의 연령을 고려한 세부적인 실험 시 방법론적인 기초 자료로서 뿐만 아니라, 교정치료 시 치수 생활력의 상실에 대한 참고 자료가 될 수 있을 것이다. Objective: This study was to change of pulp blood flow among maxillary and mandibular anterior tooth with mild crowding and adjacent teeth using Ultrasound Doppler graphy. Methods: The change of pulp blood flow was measured three times using Ultrasound Doppler graphy; before the attachment of brackets, after 3 week, and after 6 week. The sample consists of 15 year old eighteen patients. Results: Before the attachment of brackets, after 3 weeks, and after 6 weeks, there were no significant differences in the change of pulp blood flow in each part (maxilla and mandible) and each tooth according to period. In addition, to compare internal dangerousness of loss of the pulp vitality, when pulp blood flow is compared in each tooth before orthodontic treatment, there were no statistically significant differences in maxillary lateral incisor and mandibular canine but it showed low values in all measurement items (p > 0.05). Conclusions: Results of this study can be not only methodological preliminary data in further study such as tooth movement type of Ultrasound Doppler graphy and particular study considered the patient age, but also reference materials for the loss of pulp vitality in orthodontic treatment.

장중첩증을 동반한 맹장 지방종 1예

홍의실,나병규,김민옥,유일영,채지영,채희복,윤세진,이상전,송형근,박길선,정현용 충남대학교 의과대학 의학연구소 2002 충남의대잡지 Vol.29 No.2

대장 지방종은 주로 우측 결장에 호발하고 특히 회맹판 부위와 맹장 부위에 호발한다. 또한 50~60대에 빈도가 높고 증상이 있는 환자에서 장중첩증이 높게는 40~50%에서 보고되고 있어 성인 장중첩증의 원인으로 중요한 비중을 차지한다. 특히 성인 장중첩증 및 장폐쇄의 중요 원인인 악성 종양과 임상 양상이 유사하여 감별진단이 중요하다. 저자들은 반복적인 복통을 주소로 내원한 환자에서 맹장의 4×5㎝의 점막하 지방종이 말단 회장부위와 반복적인 장중첩중이 발생했던 1례를 부분 절제술로 치료하여 양호한 임상 경과를 경험하였기에 문헌 고찰과 함께 보고하는 바이다. Lipomas are one of the most common benign nonepithelial tumors of the colon which are often detected incidentally by radiologic investigation or on operation. These tumors are usually without specific symptoms. Colonic lipomas occur most often in the right colon, particularly in the ileocecal valve and the cecum. Most patients are asymptomatic. but tumors larger than 2 cm tend to produce a change in bowel habit. abdominal pain. rectorrhagia and complications including luminal obstruction or intestinal intussusception. Diagnosis can be made by colonoscopy abdominal CT. MRI, or barium enema. We report a case of lipoma of the cecum that originated in the submucosa and presented as a intussusception in a 50-year-old woman with a brief review of the literature.

안지오텐신 변환효소 억제제와 안지오텐신 II 수용체 차단제 투여 후 발생한 급성 신부전과 폐부종으로 전원된 선천성 단일신 환자의 치료 1예

백두현,김경진,홍성철,강석형,송하응,김혜인,김수현,오현정,강혜원,김서우,유민아,류동열,최규복,강덕희 이화여자대학교 의과대학 2010 EMJ (Ewha medical journal) Vol.33 No.1

Blockers of renin-angiotensin system(RAS) including ACE inhibitor or ARB are one of the most frequently prescribed medications for the treatment of hypertension, heart failure and proteinuria. One of the major side effects of these RAS blockers is the deterioration of renal function, mainly due to a reduction of intraglomerular pressure. Therefore, close monitoring of renal function is recommended when RAS blockers are initially prescribed, especially for the patients with impaired renal function. We report a patient who was transferred to our hospital due to the sudden development of oliguria and dyspnea after treatment for hypertension with ACEi and ARB. She was finally diagnosed as RAS blocker-induced acute renal failure with pulmonary edema complicated on congenital solitary kidney. After hemodialysis and conservative treatment, her renal function was recovered with maintenance of normal urine output. Conclusion:This case highlights the necessity of the functional and structural evaluation of kidney to prevent the serious complication such as acute renal failure before the administration of ACEi and/or ARB.