• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.4
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• pp.359-362
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• 2011

Purpose: This study evaluated the clinical applications of implant placement and guided bone regeneration using a mineralized bone allograft and a barrier membrane derived from ox pericardium Methods: From January 2007 to June 2009, among the patients who received an implant at Chosun University Dental Hospital, patients were selected if they were treated with guided bone regeneration (GBR) with simultaneous implant placement or GBR prior to implant placement. The selected patients were sorted according to the materials and membranes used in GBR, and the implant survival rate was recorded by clinical examination and reviewing the medical records and the radiographs. Each study list was analyzed by SPSS (version 12.0, SPSS Inc., USA) software and the survival rate was verified by Chi-square tests. $P$ values less than 0.05% were deemed significant. Results: 278 implants were placed on a total of 101 patients and 8 implants resulted in failure. Three implants failed among 15 implants with only a mineralized bone allograft. No failure was shown among the 74 implants placed with mineralized bone allograft and a barrier membrane derived from ox pericardium. One group of 4 implant placements showed failure among the 102 implants placed with a mineralized bone allograft and another bone graft material. The group that had a barrier membrane derived from ox pericardium with a mineralized bone allograft or other bone materials showed no implant failure. Three failures were shown among the 21 implants placed with only bone graft and not using a membrane. The group with membranes other than a barrier membrane derived from ox pericardium showed 5 failures among 170 implants. Conclusion: The implant survival rate of the group with GBR using a mineralized bone allograft was 96.3%, which meant there was little difference compared to the groups of another bone graft materials (98.9%). The implant survival rate of the group without a membrane-was 85.7% and it showed a significant difference compared to the group using a barrier membrane derived from ox pericardium (100%) and the group using another membrane (97.1%).

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.367-372
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• 2008

Purpose: Prevention of acute rejection in skin allografts without continuous immunosuppression lacks reports in worldwide literature. Needs for chronic immunosuppression preclude the use of tissue allograft as a routine surgical reconstructive option. Recently dendritic cells(DC) gained considerable attention as antigen presenting cells that are also capable of immunologic tolerance induction. This study assesses the effects of alloantigen-pulsed dendritic cells in induction of survival increase in a rat skin allograft model. Methods: Recipient-derived dendritic cells were harvested from rat whole blood and cultured with GM-CSF(200 ng/mL) and IL-4(8 ng/mL) for 2 weeks. Then donor-specific alloantigen pulsed dendritic cells were reinjected into tail vein before skin graft. The rat dorsal skin allografts were transplanted in 5 subgroups. Groups: I) untreated, II) anti-lymphocyte serum(ALS, 0.5 mL), III) FK-506(2 mg/kg), IV) DCp, VI) DCp and FK-506. Graft appearance challenges were assessed postoperatively. Results: The group V(DC and FK-506 treated) showed longest graft survival rate(23.5 days) than other groups; untreated(5.8 days), ALS(7.2 days), FK-506 (17.5 days), DCp(12.2 days). Conclusion: Donor antigen pulsed host dendritic cell combined with short-term immunosuppression prolong skin allograft survival and has potential therapeutic application for induction of donor antigen specific tolerance.

• Korean Journal of Radiology
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• v.20 no.6
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• pp.894-908
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• 2019

Kidney transplantation is the treatment of choice for patients with end-stage renal disease, as it extends survival and increases quality of life in these patients. However, chronic allograft injury continues to be a major problem, and leads to eventual graft loss. Early detection of allograft injury is essential for guiding appropriate intervention to delay or prevent irreversible damage. Several advanced MRI techniques can offer some important information regarding functional changes such as perfusion, diffusion, structural complexity, as well as oxygenation and fibrosis. This review highlights the potential of multiparametric MRI for noninvasive and comprehensive assessment of renal allograft injury.

• Journal of Chest Surgery
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• v.32 no.11
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• pp.984-988
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• 1999

Background: Donor-specific blood transfusion(DSBT) before organ transplantation has been demonstrated to prolong allograft survival; the mechanism of this effect has remained unclear. Only a few researches have been performed on this subject in our country. Material and Method: To investigate the effect of DSBT, we selected 5 donor recipient combinations using rats of pure strain such as PVG, ACI, and LEW. One ml of donor whole blood was transfused to each recipient through the femoral vein 7 days prior to transplantation. The donor heart was transplanted to the recipient's abdominal vessels heterotopically using modified Ono and Lindsey's microsurgical technique. Five transplantations were done for each combination. Postoperatively, donor heart beat was palpated everyday through the recipent's abdominal wall. Rejection was defined as complete cessation of donor heart beat. Result: The allogeneic heart grafts transplanted from PVG strain to ACI strain(PVG ACI) without DSBT were acutely rejected(mean survival 10.2 days). With pretransplant DSBT, the cardiac allografts in PVG ACI and LEW PVG combinations survived indefinitely(more than 100 days), those in ACI PVG combination survived 12 to 66 days(mean 31.8 days), those in PVG LEW survived 8 to 11 days(mean 10.0 days), and those in ACI LEW survived 7 to 9 days(mean 8.0 days). In brief, DSBT prior to heart transplantation was definitely effective in PVG ACI and LEW PVG combinations and moderately effective in ACI PVG combination, but not effective in PVG LEW and ACI LEW combinations. Conclusion: DSBT prior to heart transplantation showed variable effects, but might prolong cardiac allograft survival indefinitely in some donor recipient strain combinations. The mechanism of this effect should be further investigated.

• 대한미세수술학회:학술대회논문집
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• 1995.11a
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• pp.77.1-77.1
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• 1995

• The Journal of the Korean bone and joint tumor society
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• v.17 no.2
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• pp.65-72
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• 2011

Purpose: We evaluated the complications of allograft reconstruction after a bone tumor resection, and reviewed literatures to overcome such complications. Materials and Methods: We retrospectively reviewed clinical records and radiographs of fifteen patients in whom reconstruction with allograft after bone tumor resection. Results: Eight patients were men and seven were women with a mean age of 27.1 years (1-56 years) and a mean follow-up period of 89.5 months (33-165 months). All postoperative complications related to the allograft were recorded. Twenty patients (80.0%) obtained a radiologic bony union at a mean of 8.35 months (4-12 months). The mean Musculoskeletal Tumor Society score was 73.5% (46.6-93.0%). Nine patients (60.0%) experienced one event and 3 (20.0%) patients experienced multiple events during the follow-up period. Recorded events were infection (3), fracture (2), nonunion (2), limb length discrepancy (2) and varus deformity (2). The mean event free survival period was 60.8 months (6-144 months). The mean allograft survival period was 80.2 months and the 5 year survival rate of the allografts was 83.0%. Conclusion: In order to overcome complications, the combination of an allograft and vascularized fibular graft is highly recommended. In the near future, the tissue engineering technique, the application of the stem cell and PRP, could reduce the complication of allograft such as resorption and nonunion.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.73-76
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• 2010

Cardiac allograft vasculopathy (CAV) is a major factor that limits the long-term survival after cardiac transplantation. Because the main feature of CAV is a diffuse stenosis that predominantly develops in the distal arteries, reperfusion therapy has shown poor outcomes. The results of cardiac retransplantation for CAV are better than that for acute resection and the survival is identical to that of patients who undergo primary transplantation. We describe a case of performing cardiac retransplantation in a 28 year-old male patient with refractory CAV and who underwent primary transplantation due to dilated cardiomyopathy 8 years previously.

• Archives of Reconstructive Microsurgery
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• v.4 no.1
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• pp.9-15
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• 1995

Free vascularized composite tissue transfer is more frequently underwent for reconstruction of complicated tissue defects with the recent advance of microsurgery. But postoperative result was not satifactory because of donor site morbidity, flap bulkiness and cosmetic problem. So would no longer be a problem if we can obtain the exact donor tissue required for the recipient site as allotransplantation and designing the flap. Allotransplantation has been resolved with the recent development of immunosuppressive agents, while reconstruction has made great progress with the refinement of microsurgical techniques in the last 20 years. The final sucess or failure of the operative procedure in transplantation is so utterly dependent no the availability of strategies that can control the immune system effectively, selectively, safely to allow allotransplantation of a nonvital body part. 1 used 2 strains of rats, BUF and LEW, for the limb allotransplantation as a composite tissue transfer. The primary goal of this program is to improve results in clinical transplantation by accelerating the transformation of new immunological knowledge into useful medicine. Two of the most promising new immunosuppressive compounds are FK-t06(FK) and rapamycin(RPM). Both drugs are antibiotic macrolide fungal fermentation products that presumably suppress the immune system in ways similar to cyclosporin(CyA). This study shows that two new immunosuppressive drugs compare the immunosuppressive activity and effectiveness of FK-506 and RPM for prevention of the limb allograft rejection in the rat. Additional experiments investigate the dose, route of administration and histologic findings. These data demonstrates that rapamycin is far more potent and effective than FK-506 when both compounds are administered by the intraperitoneal route, as well as prolonged graft survival significantly in a dose-route dependent manner. These results lead to the view that vascularized allograft composite tissue transfer can become a reality with the expectation of possible future application in reconstructive surgery of humans.

• Journal of Chest Surgery
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• v.55 no.4
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• pp.338-356
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• 2022

Lung transplantation (LT) is now considered as an effective treatment option for end-stage lung diseases that improves the short and long-term survival rates and quality of life. As increasingly many LT procedures are being performed, the medical complications of LT are also increasing in frequency and emerging as a very important issue for transplant clinicians. Although chronic lung allograft dysfunction and infection are major causes of death after LT, many medical complications, several of which result from immunosuppressive treatment, contribute to increased mortality and morbidity. This article reviews the most frequent and important medical complications of LT, accompanied by a review of the literature and studies from South Korea, including lung allograft rejection, infection, and non-allograft organ systemic complications.

• Korean Journal of Transplantation
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• v.28 no.3
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• pp.113-120
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• 2014

Two-signal models are useful in explaining various types of immune responses. In particular, secondary, so-called costimulatory, signals are critically required for the process of T-cell activation, survival, differentiation, and memory formation. Early studies in rodent models showed that targeting T-cell costimulatory pathways elicits immunological tolerance, providing a basis for development of costimulatory therapeutics in allograft rejection. However, as the classic definition of T-cell costimulation continues to evolve, simple blockade of costimulatory pathways has limitations in prevention of allograft rejection. Furthermore, functions of costimulatory molecules are much more diverse than initially anticipated and beyond T cells. In this mini-review, we will discuss CD137-CD137L bidirectional signals as examples showing that two-signals can be applicable to multiple phases of immune responses.