• Journal of Chest Surgery
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• v.29 no.7
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• pp.713-722
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• 1996

Poor long term patient survival (60% at 2 years) in lung allograft recipients are mainly due to rejection and complications associated with the use of nonspecific immunosuppressants. Better means to achieve waft acceptance is desperately needed. 1 have investigated whether mixed allogeneic chimerism in the form of bone marrow stem cell engraftment would induce donor-specific tolerance for lung allografts. Fisher (F344) and Wistar Forth (WF)rats were lethally irradiated (1100c0y) and reconstituted with a mixture of T-cell depleted syngeneic and allogeneic bone marrow (F344+WFIWF, ACI +F344- F344). After Mixed chimerism was documented by peripheral blood Ipnphocyte typing at 28 days, orthotopic left single lung transplantation was performed, using donor-s ecific or third party allografts. No immunosuppressants were administered. Graft rejection was monitored by chest rentgenography, and con- firmed by histology Mixed chimeric rats accepted lung allografts permanently, and it was not strain specific effect. Tolerance was all or none phenomenon which had nothing to do with the percentage of chimerlsm. Mixed chimeras rejected third party allografts in less than 10 days, a time course similar to that of unmanipulated controls. No acute or chronic rejection was observed in donor specific grafts more than 150 days posttransplant. These data suggest that mixed chimerism in the form of bone marrow stem cell engraftment results in stable, systemic donor-specific transplantation tolerance for lung allografts.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1127-1133
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• 1998

Background: There are no ideal substitutes for tracheal replacement. Therefore we investigated the possibility of clinical use of cryopreserved tracheal homograft with special interest in the viability and rejection of the epithelial cell and cartilage. Material and Method: Rabbit's trachea was sected and stored in liquid nitrogen tank for 1 month. Tracheal replacement was done in 45 rabbits with autograft(n=15, Group 1), fresh allograft(n=15, Group 2) and cryopreserved homograft(n=15, Group 3). After 7, 14, and 30 days, 5 rabbits in each group were sacrificed and the regeneration of epithelium and cartilage and the degree of rejection were assessed by counting the monocellular infiltration. Result: Investigation at day 7, showed no difference in epithelial regeneration, however, at days 14 and 30, Group 1 showed better regeneration of epithelium than groups 2 and 3. There was no difference of epithelial regeneration between group 2 and 3. There was little rejection at day 7, but at days 14 and 30, there was significant rejection in group 2 and group 3.(P<0.05). Group 3 showed lesser rejection than group 2 at days 14 and 30, but it was not statistically significant. Cartilage showed no rejection and maintained its viability in groups 2 and 3. Conclusion: Cryopreserved tracheal homograft can maintain its viability, therefore it may represent a possibility of clinical application for tracheal replacement. However, cryopreservation can not eliminate the antigenicity of the trachea completely. Furthere studies for lowering the antigenicity and rejection should be performed for an ideal substitute for tracheal replacement.

• Journal of the Korean Arthroscopy Society
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• v.14 no.3
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• pp.175-179
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• 2010

동종 반월상 연골 이식술은 불가피하게 반월상 연골이 소실된 환자에서 증상을 호전을 위한 매우 효과적인 치료이다. 관절연골의 보호 효과 등 장기적인 결과에 대해서는 아직까지는 많은 연구가 필요한 상태이지만, 이러한 환자에서 반월상 연골의 기능을 회복시키기 대안이 많아 점차 널리 시행되는 추세이다. 이식된 반월상 연골이 제 기능을 하기 위해서는 적절한 수술방법을 통하여 반월상 연골 이식물을 정확한 위치에 이식을 하는 것은 필수적일 것이다. 여러 저자들 마다 서로 다른 다양한 반월상 연골 이식술의 방법들을 사용하고 있지만, 어떤 방법을 선택하던지 간에 이식된 반월상 연골의 전각 및 후각을 해부학적인 위치에 견고하게 고정을 하는 것이 매우 중요하다. 술자의 선호도에 따라 다양한 방법중의 하나를 선택을 할 수 있지만, 어떤 방법이든 수술 술기상의 어려움이 있으므로, 철저한 준비와 노력이 필요할 것이다. 본 종설에서는 반월상 연골 이식술 중 개방적 방법에 대한 간단한 소개와 함께 저자들이 사용하는 관절경을 이용한 수술방법을 정리하였다.

• Journal of the Korean Orthopaedic Association
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• v.55 no.3
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• pp.200-209
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• 2020

The first human meniscal allograft transplantations (MATs) were performed 30 years ago. In the early era, candidates were limited to patients who have favorable joint conditions. MAT is currently indicated for patients with post-meniscectomy symptoms, such as compartmental pain or effusion after a subtotal or total meniscectomy. The current indication for MAT is being expanded to other patients who were not indicated previously. The present article reviews how the indications of MAT have changed over the years.

• Journal of Veterinary Clinics
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• v.22 no.4
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• pp.322-327
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• 2005

DLA class I complement-dependent cytotoxicity (CDC) cross-match method was established to control hyperacute rejections in organ transplantation. The aim of the present study is to investigate if DLA class 1 CDC corssmatch method is effective to prevent hyperacute rejections in canine renal allografts. Seven mongrel dogs of similar age and weight were used. Erythrocyte crossmatch was first performed and only the negatives were used. Among the same blood types, CDC cross-match was performed. Anti-dog serum, Hank's balanced salt solution(HBSS), and tile self-serum was used as a positive-, a negative-, and all auto-control respectively. After the reaction with class I complement, it was stained with eosin and scored by international cytotoxicity scoring system under inverted phase microscope. According to these results, kidneys oi CDC negatives among same blood types were cross-transplanted to observe the incidence of hyperacute rejections. One of four 1.2 B blood type dogs had autoantibodies. here were negative CDC results among each blood type, and also there were negative results between different blood types. Two pairs with the same blood types and negative CDC results underwent allo-transplantation each other. There were no hyperacute rejections. DLA cross-match method studied in this experiment for canine renal allograft can be effective to prevent hyperacute rejections. it may be applicable for the future studies of histocompatibility testing in canine renal allografts.

• Journal of Chest Surgery
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• v.30 no.3
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• pp.270-274
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• 1997

In recent years, the use of allograft conduits in repair of congenital cardiac disease is widely accepted. However, the supply of homograft. is currently limiting their increased clinical application, especially small cryopreserved homografts for use in neonates and inf'ants. We used a technique to surgically reduce the size of the more readily available large-diameter allografts, making them suitable for right ventricular outflow tract reconstruction in small infants and children. From December 1994 to March 1996, a total of 11 patients ranging in age from 10 months to 6 years (mean age, 27.3 months) and ranging in weight from 5.6 to 18.5 kg (mean 11.5 kg) underwent reconstruction of the right ventricular outflow tract using this surgical technique (pulmo ary atresia with ventricular septal defect, 9 cases ; tetralogy of Falloff, 2 cases). The diameter after downsizing ranged from 14 to 19 mm with a mean of 16.8 mm. There was one operative death due to rupture of the infected homograft. Evaluation of these patients between 2 and 15 months (mean 6.9 months) after homograft implantation reveals excellent clinical and echocardiographic results. There were no significant homograft insufficiency and RVOT obstructions. Although a longer follow-up is certainly required to evaluate the long term fate of the surgically modified bicuspid homografts, we believe that this technique may represent a valuable therapeutic alternative, at least in the short term, to the use of synthetic grafts when an appropriately sized homograft is not available.

• Journal of the Korean Orthopaedic Association
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• v.56 no.1
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• pp.14-25
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• 2021

Several factors need to be considered for a successful anterior cruciate ligament (ACL) reconstruction, such as preoperative planning, operation technique, and postoperative rehabilitation. Graft choice, fixation, preparation method, maturation, incorporation to host bone, and graft tension should also be considered to achieve a good outcome after an ACL reconstruction. Factors to consider when selecting a graft are the graft strength, graft fixation, fixation site healing, and donor site morbidity, as well as the effects of initial strength, size, surface area, and origin of the graft on its potential for weakening during healing. There are two types of graft for an ACL reconstruction, autograft or allograft. Several autografts have been introduced, including the bone-patellar tendon-bone, hamstring tendon, and quadriceps tendon-bone. On the other hand, each has its advantages and disadvantages. The recent increased use of allografts for an ACL reconstruction is the lack of donor site morbidity, decreased surgical time, diminished postoperative pain, and good availability of source. Despite this, there are no reports suggesting that an allograft may have a better long-term outcome than an autograft. Allografts have inherent disadvantages, including a longer and less complete course of incorporation, remodeling, biomechanically inferiority to autograft, the potential risk of an immunogenic reaction and disease transmission. Higher long-term failure rates and poorer graft maturation scores were reported for allografts compared to autografts. An autograft in an ACL reconstruction should remain the gold standard, although the allograft is a reasonable alternative. If adequate length and diameter of autograft can be obtained for an ACL reconstruction, an autograft with adequate graft fixation and postoperative rehabilitation should be chosen instead of an allograft to achieve better results.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.17.2-17.2
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• 2011

모든 생물은 늙어가면서 그 생물체를 이루고 있는 생체조직들이 낡게 되고 약해지기 마련이며, 이외에도 자동차 사고 등 재해에 의해 생체 장기의 손상을 가져올 수도 있다. 또한 인간의 평균수명 연장과 함께 소득 수준이 높아지고 또한 'quality of life'를 추구하는 고령화 시대로 접어듦에 따라, 인공골, 인공치아 또는 인공 고/슬관절 등의 골조직 대체재료의 수요가 빠르게 증가하고 있다. 이와 같은 골조직 대체, 즉 골이식은 크게 자기골 이식(autografting), 동종이식(allografing), 인공재료(man-made materials)의 이식으로 구분된다. 현재 대체물질의 약 58%를 차지하고 있는 자기골 이식의 경우, 거부면역 반응이 없어 임상성공율이 80%에 달한다는 장점을 가지고 있으나, 비용이 비싸고 감염과 통증의 위험이 있다. 또한 시신으로부터 골을 이식하는 동종이식의 경우 대체물질의 약 34%를 차지하고 있는데, 성공률이 떨어지고 질병 감염의 위험이 있는 단점이 있다. 이외에 약 8%를 차지하고 있는 인공재료 이식의 경우, 파단, 독성반응, 마모, 골조직의 remodeling 등이 일어나는 단점이 있으나, 앞에서 언급한 바와 같이 그 필요성이 급격히 증가함에 따라 보다 나은 치료법과 골이식 대체물질의 개발에 많은 노력이 경주되고 있다. 2003년 6월 미국 Financial Times에 의하면, 인체내 식립형 생체재료의 세계시장 규모는 약 650억 달러에 이르며, 매년 200% 이상씩 신장하고 있다고 한다. 따라서 세계 각국의 의학, 약학, 임상학, 생명과학, 공학 등의 관련 연구 분야에서는 이 수요를 충족시키기 위한 활발한 연구활동을 펼치고 있다. 한편 인체내 식립용 임플란트의 국내 시장규모는 치과 임플란트의 경우 2006년 현재 2000억원 규모로, 정형외과, 악안면 성형외과, 이비인후과를 포함하면 소위 'bone-anchored metal implant' 영역의 시장 규모는 4~5조원에 이를 것으로 추산 되고 있다. 또한 소비 신장률 10~15%를 감안하면 향후 시장 규모는 폭발적으로 증가될 것으로 예상된다. 이에 발맞추어, 최근 들어 선진국은 물론, 국내에서도 인체내 식립을 목적으로 하는 생체재료에 관한 연구개발이 활발히 진행되고 있으며, 일부는 실용화 단계에 진입하고 있다. 본 강연에서는 금속 임플란트의 시장현황과 앞으로의 추세에 대하여 조망하고, Ti 임플란트를 중심으로 이의 생체활성을 부여하는 표면개질 필요성 및 최근의 연구개발 동행에 대해 소개하고자 한다.

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

• Journal of the Korean Arthroscopy Society
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• v.3 no.1
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• pp.54-61
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• 1999

The current treatment of extensive meniscal injuries has resulted in numerous investigations and clinical trials to restore normal meniscal functions. A cryopreserved meniscal allograft transplantation is one of the successful methods available to restore the meniscus. All the procedures of 26 cases were performed in an minimal open fashion, though initial four cases were done with the aid of arthroscope. In all of the grafts, we used a bone bridge which was attached to meniscus for better stability and healing. Anterior cruciate ligament reconstructions were also performed simultaneously with the meniscal procedures. We attempted to minimize articular cartilage by employing so called the "Key-hole technique" for the medial meniscus transplantation. First, the meniscal cartilage bone bridge was shaped into a cylinder and a bone tunnel was made just beside the medial border of the anterior criciate ligament insertion of the recipient knee joint, and the bone bridge of the meniscal cartilage was push to press-fit. The inserted meniscal cartilage was sutured by the usually employed technique under arthroscopic control. The lateral meniscus was shaped different to the medial meniscus in that the bone bridge was semicylindrical and the bone trough was made beside the lateral border of the anterior criciate ligament insertion of the recipient knee joint. The meniscus was put into the bone trough and the leading suture was extracted anterior to the tibia and tied the knot. The inserted meniscus was sutured in the same manner as the medial meniscus transplantation. By the above described method, the authors were able to minimize the articular cartilage invasion and transplant the meniscus with relative accuracy.