• Molecules and Cells
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• v.27 no.4
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• pp.491-492
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• 2009

We present the result of our research on the tumorigenic ability of single cell clones isolated from an aggressive murine breast cancer cell line in a matched allografting mouse model. Tumor formation is basically dependent on the cell numbers injected per location. We argue that in vivo tumor formation from single cell clones, isolated in vitro from cancer cell lines, may not provide conclusive evidence to disprove the cancer stem cell (CSC) theory without additional data.

• Molecules and Cells
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• v.26 no.5
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• pp.514-516
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• 2008

The cancer stem cell hypothesis posits that tumor growth is driven by a rare subpopulation of cells, designated cancer stem cells (CSC). Studies supporting this theory are based in large part on xenotransplantation experiments wherein human cancer cells are grown in immunocompromised mice and only CSC, often constituting less than 1% of the malignancy, generate tumors. Herein, we show that all colonies derived from randomly chosen single cells in mouse lung and breast cancer cell lines form tumors following allografting histocompatible mice. Our study suggests that the majority of malignant cells rather than CSC can sustain tumors and that the cancer stem cell theory must be reevaluated.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.322-325
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• 1996

ABO incompatible allografting is contraindicated in most organ transplantations including heart because of the hyperacute and acute rejections caused by preexisting antibodies. However several reports showed that ABO incompatible organ transplantation could be managed successfully by plasmapheresis, antibody adsorption, immunosuppression, splenectomy, and so on. We experienced one success in ABO incompatible cardiac transplantation by means of plasmapheresis and immunosuppression. However, this does not justify heart transplantation across ABO blood group barriers. Because the effect of ABO incompatibility on continued acute rejection or chronic rejection has not been fully understood, long-term follow-up study is required.

• The Journal of the Korean bone and joint tumor society
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• v.2 no.1
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• pp.78-87
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• 1996

The results of treatment of eighteen lesions of fibrous dysplasia which of them seventeen lesions were treated with surgery were reviewed at the Department of Orthopedic Surgery, College of Medicine, Hanyang University Hospital. We studied to evaluate the functional clinical results and the recurrence according to the type of disease, grafted bone, methods of treatment and location of lesion. We treated sixteen patients(five males and eleven females) and their mean age was 22.6 years. There was no association with skin pigmentation or dysfunction of endocrine system. Twelve patients had a monostotic pattern and four patients had a polyostotic pattern. Twelve lesions were treated with curettage and bone grafting and four lesions in the proximal femur were treated by internal fixation with curettage and bone grafting. One lesion was treated by en-bloc resection. There were eleven satisfactory results in twelve monostotic lesions and there were four satisfactory results in five polyostotic lesions, but the recurrence were four cases, respectively. The two unsatisfactory results were seen in two patients treated by autografting, but there were three recurrence of four lesions in autografting only, one of five in autografting and allografting, four of eight in allgrafting or xenografting. Four of six lesions in upper extremity were recurred after curettage and bone grafting and five of them showed satisfactory results. In pelvic and lower extremity lesions, the recurrence were occurred in two lesions after curettage and bone grafting and in two lesions after internal fixation and bone grafting. The recurrence does not always provide an unsatisfactory functional results and the recurrence showed higher rate in radiologic pattern of ground glass appearance with-out marginal sclerotic rim, but the recurrence according to grafted bone showed similar rates. Curettage and bone grafting is adequate for a symptomatic lesion and firm internal fixation is needed for a lesion in proximal femur. In use of grafted bone, xenograft or allograft may be preferable to autograft because of the disadvantage of autografting like a increased blood loss, prolonged operation times, etc.

• Clinics in Shoulder and Elbow
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• v.19 no.4
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• pp.216-222
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• 2016

Background: We investigated the effectiveness of fibular strut allograft augmentation of proximal humerus fractures to prevent varus deformity in patients over the age of 65 years with insufficient medial support. Methods: We analyzed the clinical and radiological outcomes of locking plate fixation with adjunct fibular strut allograft augmentation in 21 patients with proximal humeral fractures. The inclusion criteria were age (65-year-old or older); presence of severe medial comminution; inadequate medial support; and those who could participate in at least a one year follow-up. The average age was 76.4 years. We analyzed each patient's Constant score, our indicator of clinical outcome. As radiological parameters, we analyzed time-to-bone union; restoration of the medial hinge; difference between the immediately postoperative and the last follow-up humeral neck-shaft angles;; and anatomical reduction status, which was assessed using the Paavolainen method. Results: A successful bone union was achieved in all patients at an average of 11.4 weeks. We found that the average Constant score was 74.2, showing a satisfactory outcome. The average difference in the humeral neck-shaft angles between the immediately postoperative time-point and at the final follow-up was $3.09^{\circ}$. According to the Paavolainen method, the anatomical reduction was rated excellent. The medial hinge was restored in 14 of 21 patients. Although we did not find evidence for osteonecrosis, we found that a single patient had a postoperative complication of screw cut-out. Conclusions: Fibular strut allografting as an adjunct treatment of proximal humeral fractures may reduce varus deformity in patients with severe medial comminution.

• Archives of Plastic Surgery
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• v.50 no.4
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• pp.415-421
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• 2023

The revision of the Korea Organ Transplantation Act (KOTA) in 2018 included hand/arm among the organs that can be transplanted. The first hand transplantation since the revision of KOTA took place in January 2021. A 62-year-old male patient experienced hand amputation on July 13, 2018, by a catapult injury. The patient first visited our institute 3 months after the injury. After serial interviews and an overall evaluation, the patient was registered on the hand transplantation waiting list in January 2020. On January 9, 2021, the patient underwent hand transplantation at the right distal forearm level. The total operation time was 17 hours 15 minutes, and the cold ischemic time was 4 hours 9 minutes. Postoperative immunosuppression was administered based on the protocol used for kidney transplantation. Two acute rejection episodes occurred, on postoperative days 33 and 41. Both rejection episodes were reversible with rescue therapy of a higher tacrolimus trough level, steroid pulse therapy, and topical immunosuppressants. Controlled passive range of motion exercise was started on postoperative day 10. Dynamic splint was applied on postoperative day 18. At 1 year, graft maintenance and functional improvement were satisfactory, and the patient showed a Disabilities of Arm, Shoulder and Hand score of 25.8. We successfully performed the first hand transplantation surgery under the KOTA amendment. It came from the organic and effective cooperation of plastic, orthopaedic, and transplantation departments and we believe it will guarantee the future ongoing success.

• Journal of Periodontal and Implant Science
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• v.24 no.3
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• pp.618-632
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• 1994

The ultimate goal of periodontal therapy is promoting the regeneration of lost periodontal tissue. The purpose of this study is to evaluate the effect of treatment using decalcified freeze dried bone allograft as a bone graft material. 47 intrabony defects from 27 patients with clinical diagnosis of chronic periodontitis were selected among those 24 defects were treated via flap operation only and designated as the control group, the other 23 defects were treated with decalcified freeze dired bone allografting via flap operation and designated as the experimental group. Clinical parameters including probing depth, loss of attachment, probing bone level and gingival recession have been recorded at 6th months, and the significance of the changes has been analyzed. The results are as follows : 1. Probing depths were reduced significantly in both control group($2.75{\pm}0.99mm$) and experimental group($3.69{\pm}0.97mm$) postoperatively(p<0.01). Experimental group showed significantly higher decrease compared to the control group(p]0.01). 2. Loss of attachment showed statistically significant decrease in both control group($1.77{\pm}1.08mm$) and experimental group postoperatively($2.70{\pm}1.55mm$). Experimental group showed significantly higher decrease compared to the control group(p]0.05). 3. Probing bone levels were reduced with statistically significance in both control group($1.08{\pm}0.97mm$) and experimental group($4.00{\pm}1.41mm$) postoperatively(p<0.01). Experimental group showed significantly higher decrease compared to the control group(p<0.01). 4. Gingival recession showed statistically significant increase in the control group($1.21{\pm}0.72mm$) and experimental group($1.00{\pm}1.09mm$) postoperatively(p<0.01). There was no statistical significance between the control group and the experimental group. On the basis of these results, treatment using allogenic decalcified freeze dried bone is effective in reducing probing depth, loss of attachment and probing bone level. Therefore allogenic decalcified freeze dried bone is an effective bone graft material in periodontal regeneration.

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.385-392
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• 2008

Purpose: The most effective methods of harvesting, preparing, and injecting autologous fat grafts have been inconsistent and conflicting. With its limitation as resorption in fat grafting, handling various techniques affect adipocyte survival, and is crucial to optimizing its long-term survival. To improve graft survival, re-implantation of cryopreserved adipocytes was developed. In addition, adipocytes do not induce immune rejection in response to non-self lymphocytes in a mixed lymphocyte reaction. The purpose of this study is to analyze the changes in cryopreserved adipocytes so as to determine the most efficient long-term storage period, and to analyze the changes in cryopreserved allografted adipocytes so as to determine the efficacy of cryopreserved adipocytes allografting. Methods: Fat tissues were harvested from the inguinal and retroperitoneal fat pad of mice. After the centrifugation of the harvested fat tissues, they were disintegrated with collagenase. The adipocytes were obtained by centrifugation of the disintegrated fat tissues. The adipocytes were treated as follows: (1) They were examined for weight and then frozen at $-20^{\circ}C$(n=25). For four months, each five frozen samples were taken and examined for weight and histologic changes in the 1st week, the 1st month, the 2nd month, the 3rd month, and the 4th month, respectively. (2) The adipocytes were immediately frozen at $-20^{\circ}C$(n=125). For four months, five frozen samples were taken, and allografted in the same time period as above. Finally, for four months, five cryopreserved allografted adipocytes were taken and examined for histologic changes in the same time period as above. Results: (1) Significant weight changes and histologic findings with inflammatory and destructive changes were observed in the cryopreserved adipocytes in three months. (2) Significant fat necrotic changes in the histologic changes with Hematoxylin and eosin stain were observed in the cryopreserved allografted adipocytes since the first week, independent of the freezing period. Conclusion: The study results show that the adipocytes that were cryopreserved for more than three months underwent obvious weight reductions and necrotic changes, and the adipocytes that were allografted without freezing were viable for four months, but the cryopreserved allografted adipocytes had obvious necrotic changes since the first week regardless of the freezing period.