• Bulletin of the Korean Chemical Society
• /
• 제29권2호
• /
• pp.422-426
• /
• 2008

Hemodialysis graft coated with paclitaxel prevents stenosis; however, large initial burst release of paclitaxel causes many negative effects such as drug toxicity and inefficient drug loss. Therefore we developed and tested a novel coating method, double dipping, to provide controlled and sustained release of paclitaxel locally. Expanded polytetrafluoroethylene (ePTFE) grafts were dipped twice into a solution of several different paclitaxel concentrations. In vitro release tests of the double dipping method showed that early burst release could be somewhat retarded and followed by sustained release for a long time. We observed the effect of paclitaxel coating by double dipping in porcine model of arterio-venous (AV) grafts between the common carotid artery and the external jugular vein. 12 weeks after constructing AV grafts, cross sections of the graft venous anastomosis were obtained and analyzed. Paclitaxel coated ePTFE grafts by double dipping were observed to prevent neointimal hyperplasia and therefore reduced stenosis of the arteriovenous hemodialysis grafts, especially at the graft venous anastomosis sites. Our results demonstrate that second dipping of ePTFE graft, which was already coated once with paclitaxel, washes off the drug on a surface of the graft and affects the ratio of paclitaxel on the surface to that of the inner space, possibly by diffusion: thus the early burst of drug can be somewhat reduced.

• Archives of Plastic Surgery
• /
• 제38권5호
• /
• pp.567-575
• /
• 2011

Purpose: Acellular human dermis is very useful implant for use in plastic and reconstructive surgery. However, the volume of acellular human dermis graft is known to decrease for a long time. Basic fibroblast growth factor (bFGF) is a polypeptide that enhances the collagen synthesis and angiogenesis. In the current study we examined whether bFGF could improve the survival of acellular human dermis ($SureDerm^{(R)}$) by increasing angiogenesis of the graft. Methods: Forty rats were divided into two groups (control and bFGF). A 2-mm thick piece of $SureDerm^{(R)}$ was cut into smaller pieces that were $15{\times}5$ mm in size. Two subcutaneous pockets were made on the back of each rat. Grafts sprayed with bFGF were implanted in the bFGF group and injected with bFGF after transplantation every 3 days for 2 weeks. In the control group, the grafts were treated with phosphate-buffered saline (PBS) instead of bFGF. Four days, and 1, 4, and 12 weeks after the implantation, the grafts were harvested and gross and histologic examinations were performed. Inflammation grade, graft thickness, neocollagen density, and neocapillary count were measured. Results: The bFGF group displayed more rapid accumulation of inflammatory cells with a higher density of neocapillaries, and increased active collagen synthesis. After 12 weeks, the thickness of the grafts in the control and bFGF groups was $75.15{\pm}4.80%$ and $81.79{\pm}5.72%$, respectively, in comparison to the thickness before transplantation. There was a statistically significant difference between both groups ($p$ <0.05). Conclusion: bFGF was effective in reducing the absorption of acellular human dermal grafts by increasing angiogenesis and accelerating engraftment. In conclusion, bFGF may be a good tool for use in acellular human dermal graft transplantation for reconstructive surgery involving soft-tissue defects.

• Journal of Chest Surgery
• /
• 제44권5호
• /
• pp.323-331
• /
• 2011

Background: Myocardial revascularization in patients with renal insufficiency is challenging to the cardiac surgeon, irrespective of utilizing extracorporeal circulation. This study aimed to compare the number of bypass grafts and the mid-term results and to evaluate independent survival predictors in patients with renal insufficiency undergoing on-pump or off-pump myocardial revascularization. Materials and Methods: We retrospectively analyzed the data of 103 patients with renal insufficiency, who had isolated myocardial revascularization between January 1999 and January 2009. The patients were divided into two groups, the on-pump group and the off-pump group. Results: The off-pump group received a significantly greater number of distal arterial grafts than the on-pump group. However, the mean number of total grafts, the degree of complete revascularization, and survival rate of the patients were not significantly different between the two groups. Multivariate analysis showed the independent predictors for reduced mid-term survival were the number of total grafts and postoperative periodic renal replacement therapy. Off-pump myocardial revascularization does not decrease the number of bypass grafts or influence on the mid-term results for patients with renal insufficiency, compared to on-pump myocardial revascularization. Conclusion: Myocardial revascularization with a large number of total grafts has a beneficial effect on survival in patients with renal insufficiency, irrespective of utilizing extracorporeal bypass.

• Archives of Plastic Surgery
• /
• 제46권2호
• /
• pp.152-159
• /
• 2019

Background Nasal framework-supporting procedures such as septal extension grafts, derotation grafts, and columellar strut grafts are usually required in rhinoplasty in Asian patients because the skin envelope is tight, but the nasal framework is small and weak. Autologous materials are preferred, but they have some limitations related to the amount that can be harvested and the frequency of use. Therefore, synthetic materials have been used to overcome these limitations. Methods A total of 114 patients who received a polydioxanone (PDS) plate as an adjuvant material in rhinoplasty from September 2016 to August 2017 were retrospectively investigated. The PDS plate was used as to support the weak framework and to correct the contour of the alar cartilages. The PDS plate was used for reinforcement of columellar struts and septal L-struts, alar cartilage push-down grafts, fixation of septal extension grafts, and correction of alar contour deformities Results Primary and secondary rhinoplasty was performed in 103 and 11 patients, respectively. Clinically, no significant inflammation occurred, but decreased projection of the tip was observed in seven patients and relapse of a short nose was noted in five patients. Conclusions PDS plates have been used in the United States and Europe for more than 10 years to provide a scaffold for the nasal framework. These plates can provide reinforcement to columellar struts, L-struts, and septal extension grafts. In addition, they can assist in deformity correction. Therefore, PDS plates can be considered a good adjuvant material for Asian patients with weak and small nasal cartilage.

• Journal of Chest Surgery
• /
• 제54권6호
• /
• pp.500-508
• /
• 2021

Background: The major limitation of arteriovenous graft access is the high incidence of thrombotic occlusion. This study investigated the outcomes of our salvage strategy for thrombosed hemodialysis arteriovenous grafts (including surgical thrombectomy with balloon angioplasty) and evaluated the efficacy of intragraft curettage. Methods: Salvage operations were performed for 290 thrombotic occluded arteriovenous grafts with clinical stenotic lesions from 2010 to 2018. Of these, 117 grafts received surgical thrombectomy and balloon angioplasty from 2010 to 2012 (group A), and 173 grafts received surgical thrombectomy and balloon angioplasty, with an additional salvage procedure using a curette and a graft thrombectomy catheter, from 2013 to 2018 (group B). Outcomes were described in terms of post-intervention primary patency and secondary patency rates. Results: The post-intervention primary patency rates in groups A and B were 44.2% and 66.1% at 6 months and 23.0% and 38.3% at 12 months, respectively (p=0.003). The post-intervention secondary patency rates were 87.6% and 92.6% at 6 months and 79.7% and 85.0% at 12 months, respectively (p=0.623). Multivariate Cox regression analysis demonstrated that intragraft curettage was a positive predictor of post-intervention primary patency (hazard ratio, 0.700; 95% confidence interval, 0.519-0.943; p=0.019). Conclusion: Surgical thrombectomy and balloon angioplasty showed acceptable outcomes concerning post-intervention primary and secondary patency rates. Additionally, intragraft curettage may offer better patency to salvage thrombotic occluded arteriovenous grafts with intragraft stenosis.

• Journal of Chest Surgery
• /
• 제56권5호
• /
• pp.313-321
• /
• 2023

Background: This study evaluated the early, 1-year, and 3-year graft patency rates and mid-term clinical outcomes after no-touch saphenous veins (NT-SVs) were used as aortocoronary grafts in coronary artery bypass grafting (CABG). Methods: In total, 101 patients who underwent CABG using NT-SVs as aortocoronary grafts were included. The 2 most common indications for performing aortocoronary grafting with NT-SVs were unavailability of the left internal thoracic artery (n=36) and moderate lesions where flow competition was expected (n=27). Early (median, 1 day; interquartile range [IQR], 1-2 days), 1-year (median, 13 months; IQR, 11-16 months), and 3-year (median, 34 months; IQR, 27-41 months) graft angiography was performed in 98 (97.0%), 84 (83.2%), and 40 patients (39.6%), respectively. The median follow-up duration was 43 months (IQR, 13-76 months). Overall survival rates and the cumulative incidence of major adverse cardiac events were evaluated. Results: The operative mortality rate was 2% (2 of 101 patients). Early postoperative patency rates for overall and aortocoronary NT-SV grafts were 98.2% (223 of 227 distal anastomoses) and 98.2% (164 of 167), respectively. The 1- and 3-year patency rates for aortocoronary SV grafts were 94.9% (131 of 138) and 90.6% (58 of 64), respectively. The overall survival rates at 5 and 10 years were 81.7% and 59%, respectively. The cumulative incidence of major adverse cardiac events at 5 and 10 postoperative years was 20.7% and 39%, respectively. Conclusion: The feasibility of using NT-SVs as aortocoronary grafts in CABG was shown in this study, based on the graft patency rates up to 3 years and the mid-term clinical outcomes.

• Investigative Magnetic Resonance Imaging
• /
• 제7권1호
• /
• pp.22-30
• /
• 2003

목적 : 본 연구에서는 호흡멈춤 K-space 분할 2D-FASTCARD 자기공명영상 기법에 의한 관상동맥우회로내의 혈류개방성 검사의 임상 적 유용성을 조사하였다. 대상 및 방법: 관상동맥우회로 시술을 한 38명의 환자에서 내유동맥의 수는 36개이었고 대복제정맥편은 56개였다. 2차원 FASTCARD 기법을 이용하여 sagittal과 transverse평면에서 13-18초 동안 호흡을 멈추고 영상을 심장박동주기에 맞추어 획득하였다. 신호크기-영상의 hard copy를 이용하여 관상동맥우회로가 예상되는 지점에서 혈류에 의한 작은 원형부분이 밝게 보이면 해당 graft가 개방되었다고 판독하였다. 결과: 시술 환자의 다양한 관상동맥우회술의 양상에 따라 분류하여 Sagittal평면과 transverse 평면에서 내유동맥편과 대복제정맥편의 개방성을 검사하였다 좌회선지관상동맥의 분지로 연결되는 대복제정맥편은 Sagittal평면에서, 좌전하행지 관상동맥 혹은 그의 분지나 우관상동맥으로 연결되는 내유동맥편 혹은 대복제정맥편은 transverse평면에서 최대 감도의 개방성 영상을 보였다. 전체 38명의 환자 중에 23명의 영상획득 가능환자에서 45개의 관상동맥우회로가 보였으며 9개가 보이지 않았다. 증상이 있던 두 명의 환자중 2개의 관상 동맥우회로가 보이지 않았다. 결론: 호흡멈춤 K-space 분할 2D-FASTCARD 자기공명영상 기법으로 관상동맥우회로의 혈류 개방성의 비침습적 평가가 가능하다. 그러나 이 방법으로 보이지 않는 관상동맥 우회로는 조영제를 사용한 자기공명 혈관조영술이나 일반 혈관조영술등의 방법으로 그 진위를 재검사하여 확진하는 것이 필요하다.

• 한국산림과학회지
• /
• 제85권3호
• /
• pp.532-538
• /
• 1996

Indoor seed orchard의 가능성을 시험하기 위해 온실의 화분에서 자라는 낙엽송 접목묘와 야외에서 자라는 실생묘에 Gibberellins(GA4/7) 살포, 주입 및 몇가지 보조 처리를 사용하여 조기개화를 유도하였다. 온실의 화분에 지라는 접목묘에 대해서는 GA4/7 반복 살포 단독처리가 가장 효과적이었으나 보조 처리로서 사용된 root pruning은 상승효과를 보이 지 못했다. GA4/7 주입은 접목표의 치사를 초래하였기 때문에 유용한 방법이 아니었다. 10년생 실생묘를 이용한 야외실험에서는 GA4/7 살포와 보조처리로서 root pruning 또는 plastic mulching의 사용이 개화의 유도에 가장 효과적이었다.

• Journal of Chest Surgery
• /
• 제26권4호
• /
• pp.271-275
• /
• 1993

In this country, the number of patients with coronary artery disease is progressively increasing with the change of life style and improvement of the diagnostic procedures. In addition, the medically invasive procedure for treating ischemic heart disease was rapidly developed and the surgical patients have more complex and multiple lesions and more surgical risks. Fifty three patients with ischemic heart disease underwent coronary bypass grafting [CABG] for recent 24 months. Twenty patients had three-vessel disease, 17 patients two-vessel disease, and 2 patients single-vessel disease. The average number of distal anastomoses was 3.3 per patient with the range of I to 6 grafts. Forty-one patients [77.4 %] had preoperative left ventricular ejection fraction of 50 % or more and 14 patients[26.4%] had a significant left main coronary lesion. Saphenous vein grafts were employed in 52/53 patients [98.1%] and internal mammary grafts, which were anastomosed to left anterior descending artery, in 38/53 patients[71.7%]. Two patients, whom percutaneous transluminal coronary angioplasty failed for, underwent emergency CABG with only saphenous vein grafts and both patients survived.The hospital mortality was 1.9 % and there was no late death. Perioperative myocardial infarction occurred in 1.9%. All survivors were asymptomatic[in 83% of the patients] and/or improved over their preoperative status. Twenty-nine patients were included in blood conservation group and 21 patients [72.4 %] underwent CABG without any homologous blood transfusion. Our early result of coronary bypass grafting was comparable to that which was reported in other coronary surgery units.

• Archives of Plastic Surgery
• /
• 제42권3호
• /
• pp.341-345
• /
• 2015

Background A tie-over dressing is the accepted method to secure skin grafts in order to prevent haematoma or seroma formation. We describe the novel application of a barbed suture tie-over for skin graft dressing. The barbs act as anchors in the skin so constant tensioning of the suture is not required. Methods From January 2014 to August 2014 we used the technique in 30 patients with skin defects requiring split-thickness or full-thickness grafts. Patient demographics, clinicopathological details and graft outcome were collected prospectively. Results The majority of cases were carried out for split-thickness skin grafts (n=19) used on the lower limb (n=20). The results of this novel technique were excellent with complete (100%) graft take in all patients. Conclusions Our results demonstrate the clinical application of a barbed device for securing skin grafts with excellent results. We find the technique quick to perform and the barbed device easy to handle, which can be applied without the need for an assistant.