• 대한소아치과학회지
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• 제34권1호
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• pp.53-61
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• 2007

치아우식증이나 치주질환으로 치아를 상실한 경우 여러 가지 방법으로 수복 치료할 수 있으나 그 중에서 임플란트와 치아 이식에 대한 관심이 높아지고 있다. 최근에는 치아 이식에 대한 성공률을 높이기 위해서 치아를 형성시키고 발육시키는 과정에 관한 많은 연구가 이루어지고 있다. 치아싹 이식은 생체 내와 생체 외에서 연구되고 있고, 생체 내 이식은 쥐와 생쥐, 고양이, 개 등 여러 동물에서 시행되고 있다. 이러한 생체 내 이식은 대부분 구강 외에서 시행되고 있으며 구강 내 이식에 대한 연구는 드물다. 본 연구는 악골 내에 이식한 치아싹이 발육되고 석회화되는지 관찰하기 위하여 성숙한 흰쥐의 상악 제 1 구치를 발치하고 그 발치와에 임신 13.5일 된 태아쥐에서 모상기의 하악 제 1 구치의 치아싹을 이식하고 2, 6 개월 후 희생하여 방사선학적 그리고 조직학적으로 관찰하여 다음과 같은 결과를 얻었다. 12 개월과 6개월 동안 악골 내에 이식한 치아싹은 석회화된 치아 조직이 형성 되었고 치아 조직에서 상아질과 백악질, 치수 조직이 관찰되었으며 법랑질 공간 주변은 상피로 둘러싸여 있었다. 2. 6개월 동안 구강 상피 하방에 위치한 치아 조직은 상피로 둘러싸여 있었고 주위에 치주인대 및 결합조직이 관찰되었다. 3. 이식한 시간이 경과함에 따라 치아 형성이 진전되었으나 치아 조직은 크기가 작았고 형태학적으로 완전하지 못하였다.

• Archives of Plastic Surgery
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• 제32권4호
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• pp.533-538
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• 2005

Due to its safety and softness, autologous fat transplantation has been commonly performed for soft tissue correction. However, the injected fat is absorbed resulting in the reduction of volume of the graft by 40-60% within a few months. Thus, there was an attempt to use adipocytes differentiated from preadipocytes in vitro for transplantation. Differentiated adipocytes were biocompatible and matured with gradual volume increase at transplantation site in clinical study(unpublished data). In addition, they did not induce immune rejection in response to nonself lymphocytes in a mixed lymphocyte reaction(MLR)(unpublished data). The purpose of this study is to differentiate mouse preadipocytes following labeling into adipocytes to establish an animal model for allogenic transplantation. Preadipocytes isolated from inguinal and retroperitoneal fat pad of C57BL/6 mice were proliferated with growth medium by passage 3 and differentiated into adipocytes with different culture conditions after labeled with BrdU. At most suitable conditions, above 90% of preadipocytes were differentiated and BrdU labeling did not affect differentiation rate and function of differentiated adipocytes. These results demonstrate that BrdU-labeled adipocytes resulting from this in vitro differentiation protocol are useful for allogenic transplantation study.

• IMMUNE NETWORK
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• 제11권6호
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• pp.358-363
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• 2011

Background: Traditionally, interferon-${\gamma}$ (IFN-${\gamma}$) was regarded as a pro-inflammatory cytokine, however, recent reports suggested role of IFN-${\gamma}$ in immune tolerance. In our previous report, we could induce tolerance to male antigen (HY) just by male islet transplantation in wild type C57BL/6 mice without any immunological intervention. We tried to investigate the influence of IFN-${\gamma}$ deficiency on tolerance induction by male islet transplantation. Methods: To examine the immunogenicity of male tissue in the absence of IFN-${\gamma}$, we transplanted male IFN-${\gamma}$ knock-out (KO) skin to female IFN-${\gamma}$ KO mice. Next, we analyzed male IFN-${\gamma}$ KO islet to streptozotocin-induced diabetic female IFN-${\gamma}$ KO mice. And, we checked the functionality of grafted islet by graft removal and insulin staining. Results: As our previous results in wild type C57BL/6 mice, female IFN-${\gamma}$ KO mice rejected male IFN-${\gamma}$ KO skin within 29 days, and did not reject male IFN-${\gamma}$ KO islet. The maintenance of normal blood glucose level was dependent on the presence of grafted male islet. And the male islet recipient did not reject 2nd challenge of male islet graft also. Conclusion: Deficiency of IFN-${\gamma}$ does not have influence on the result of male skin graft and male islet transplantation. Conclusively, male islet transplantation induced T cell tolerance is not dependent on the presence of IFN-${\gamma}$.

• 폴리머
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• 제38권2호
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• pp.113-128
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• 2014

Tissue engineering and regenerative medicine strategies could offer new hope for patients with serious tissue injuries or end-stage organ failure. Scientists are now applying the principles of cell transplantation, material science, and engineering to create biological substitutes that can restore and maintain normal function in diseased or injured tissues/organs. Specifically, creation of engineered tissue construct requires a polymeric biomaterial scaffold that serves as a cell carrier, which would provide structural support until native tissue forms in vivo. Even though the requirements for scaffolds may be different depending on the target applications, a general function of scaffolds that need to be fulfilled is biodegradability, biological and mechanical properties, and temporal structural integrity. The scaffold's internal architecture should also enhance the permeability of nutrients and neovascularization. In addition, the stem cell field is advancing, and new discoveries in tissue engineering and regenerative medicine will lead to new therapeutic strategies. Although use of stem cells is still in the research phase, some therapies arising from tissue engineering endeavors that make use of autologous adult cells have already entered the clinic. This review discusses these tissue engineering and regenerative medicine strategies for various tissues and organs.

• 대한미세수술학회:학술대회논문집
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• 대한미세수술학회 1998년도 제18차 학술대회
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• pp.195-196
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• 1998

• Journal of Cardiovascular Imaging
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• 제30권4호
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• pp.263-275
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• 2022

BACKGROUND: Cardiac allograft vasculopathy (CAV) is a complication beyond the first-year post-heart transplantation (HTx). We aimed to test the utility of cardiac magnetic resonance (CMR) to detect functional/structural changes in HTx recipients with CAV. METHODS: Seventy-seven prospectively recruited HTx recipients beyond the first-year post-HTx and 18 healthy controls underwent CMR, including cine imaging of ventricular function and T1- and T2-mapping to assess myocardial tissue changes. Data analysis included quantification of global cardiac function and regional T2, T1 and extracellular volume based on the 16-segment model. International Society for Heart and Lung Transplantation criteria was used to adjudicate CAV grade (0-3) based on coronary angiography. RESULTS: The majority of HTx recipients (73%) presented with CAV (1: n = 42, 2/3: n = 14, 0: n = 21). Global and segmental T2 (49.5 ± 3.4 ms vs 50.6 ± 3.4 ms, p < 0.001;16/16 segments) were significantly elevated in CAV-0 compared to controls. When comparing CAV-2/3 to CAV-1, global and segmental T2 were significantly increased (53.6 ± 3.2 ms vs. 50.6 ± 2.9 ms, p < 0.001; 16/16 segments) and left ventricular ejection fraction was significantly decreased (54 ± 9% vs. 59 ± 9%, p < 0.05). No global, structural, or functional differences were seen between CAV-0 and CAV-1. CONCLUSIONS: Transplanted hearts display functional and structural alteration compared to native hearts, even in those without evidence of macrovasculopathy (CAV-0). In addition, CMR tissue parameters were sensitive to changes in CAV-1 vs. 2/3 (mild vs. moderate/severe). Further studies are warranted to evaluate the diagnostic value of CMR for the detection and classification of CAV.

• Archives of Reconstructive Microsurgery
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• 제9권1호
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• pp.27-36
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• 2000

February 1995 to September 1999, authors have experienced seven cases of infected nonunion of tibial fractures with associated soft tissue injury and skin defect, and have accomplished union in all cases by free vascularized fibular graft. All grafts healed with no radiographic evidence of bone necrosis or resorption and have been able to treat large bony defect and skin defect simultaneously. In this study, five cases of vascularized free fibular osteocutaneous flap transfer and two cases of free fibular graft are reported. All of seven cases were infected nonunion of tibia. The results were obtained as follows 1) The mean duration of the radiologic bone union was average 5.3months. 2) Grafted fibular has been hypertrophied, average 10.6 months. 3) In five cases of preservation of posterior cortex of tibia, bony union and hypertrophy of grafted bone were earlier than that two cases of complete segmental resection of tibia. 4) In two cases which only free vascularized fibular graft were performed because achievement of cutaneous flap was failed, authors found that soft tissue defect was filled with granulation tissue and split-thickness skin graft was possible over the granulation tissue after 3 weeks postoperatively.

• International Journal of Stem Cells
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• 제9권2호
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• pp.186-191
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• 2016

Background and Objectives: With the global demand for dairy protein for consumption growing annually, there has been increasing activity in the research field of dairy protein synthesis and production. From a manipulation perspective, it is more difficult to use live cattle for laboratory studies on the production of milk as well as of dairy protein such as casein, as compared with using laboratory animals like rodents. Therefore, we aimed to develop a mouse model of bovine mammary alveolar ducts for laboratory-scale studies. We studied the formation of the bovine mammary gland ductal structure by transplanting the MAC-T bovine alveolar cell line into mice. Methods and Results: MAC-T cells ($1{\times}10^7$) were suspended in Matrigel and injected into the dorsal tissue of 8-week-old male BALB/C nude mice. Histological analysis of tissue dissected from the MAC-T cell-transplanted mice after 6 weeks showed the typical morphology of the tubuloalveolar female gland, as well as glands made up of branching ducts that were surrounded by smooth muscle with small alveoli budding off the ducts. In addition, the epithelial markers CK14 and CK18 were expressed within the duct-like structure. Prolactin was detected in the duct interior in these CK14+ and CK18+ cells but not in the non-transplanted MAC-T cells. Conclusions: These results showed that duct-like tissue had been successfully formed after 6 weeks of transplantation of the CK14+ and CK18+ MAC-T cells into mice dorsal tissue. This mouse model will be a useful tool for further research on the bovine mammary gland.

• Archives of Reconstructive Microsurgery
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• 제14권1호
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• pp.14-17
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• 2005

Purpose: Authors have performed free tissue transplantation in the upper and lower extremities with sensory flaps and evaluated the sensory function recovery. Materials and methods: Between 1992 through 2004, sensory free flap articles published in the journal of the Korean microsurgical society, were reviewed and recovery of sensory function was assessed by static two-point discrimination test. Results: Static two point discrimination test showed average 6.7 mm in the thumb, average 12 mm in the hand and 7 cm of the dorsalis pedis flap, 20.5 mm of the lateral arm flap and over 8 cm of the forearm flap in the foot. Conclusion: Sensory flaps provide the protective and useful coverage in the upper and lower extremities and have benefit for activities for daily life in free tissue transferred patients.

• Archives of Reconstructive Microsurgery
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• 제11권2호
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• pp.167-172
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• 2002

The only treatment method for crushed soft tissue injuries in the proximal leg involving the knee joint is the microsurgical free flap transplantation, especially latissimus dorsi myocutaneous free flap is useful to cover the extensive soft tissue defects, therefore prevents iatrogenic below knee amputation and facilitates early wound healing, early ambulation and shortens hospital stay. Authors have treated the open amputation with crushed soft tissue and bone injuries in the proximal leg, and the repeated abrasion and infectious wound with traumatic neuroma in the below knee with myocutaneous free flap and succeeded to wear below knee amputation prosthesis and return to normal activities of the daily living in the relatively shorter period than usual.