• 분석과학
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• 제17권1호
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• pp.60-68
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• 2004

폴리올레핀 부직포는 녹는점이 ${\sim}162^{\circ}C$며 구성비가 40%인 폴리프로필렌과 녹는점이 ${\sim}132^{\circ}C$며 구성비가 60%인 폴리에틸렌으로 구성된것을 이용하였다. 전지격막을 제조하기 위하여 방사선그래프트 법을 이용하여 이 폴리올레핀에 스틸렌을 그래프트 시킨 후 다음으로 술폰산기를 도입하였다. 술폰산기를 갖은 폴리올페핀 부직포를 XPS, SEM, DSC, TGA, 및 Porosimeter를 사용하여 특성 평가 하였다. 술폰화 반응후, 폴리올레핀 부직포에 대한 전해질 보존 (electrolyte retention), 전기저항 (electrical resistance) 및 $K^+$에 대한 운반율과 같은 전기화학적 특성을 조사하였다. 그 결과 술폰산기의 함량이 증가하면 할수록 전해질 보존율은 증가하였으며 반면에 전기저항은 감소하는 사실을 알았다. 또한 술폰산기의 함량이 0.22 ~ 3.60 mmol/g에서 $K^+$의 운반율은 0.90 ~ 0.93이었다.

• Composites Research
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• 제32권6호
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• pp.335-341
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• 2019

본 연구는 전자선 조사를 이용하여 폴리프로필렌(polypropylene, PP) 부직포에 아크릴산(acrylic acid, AAc)을 그라프트 한 후 납 이온에 대한 흡착성능을 평가하였다. 다양한 조건에서 그라프트를 실시하여 조사량 100 kGy, 단량체 농도 60%에서 약 50%의 그라프트율을 갖는 아크릴산이 그라프트 된 폴리프로필렌(PP-g-AAc) 부직포를 제조하였다. 제조된 PP-g-AAc 부직포의 물리/화학적 특성을 SEM, ATRIR, 열분석, 인장강도 등의 분석을 통해 평가하였다. SEM으로 확인한 PP와 PP-g-AAc 부직포의 형태에는 큰 변화가 없었으며, ATR-FTIR 결과로부터 PP 부직포에 AAc가 도입되었다고 판단하였다. PP-g-AAc 부직포는 PP 부직포와 비교하여 인장강도는 증가하고 인장변형률은 감소하였다. 하지만 그 변화의 값이 크지 않아 물리적 특성에 큰 영향력은 없을 것이라 판단된다. 다양한 이온들에 대한 PP-g-AAc 부직포의 흡착특성을 평가한 결과 납에 대해 선택적 흡착 거동을 보였다. 결론적으로, 본 연구에서 제조된 PP-g-AAc는 납 이온 흡착을 위한 흡착제로서 응용이 기대된다.

• 대한두개안면성형외과학회지
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• 제21권4호
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• pp.229-236
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• 2020

Background: Oncologic resection of the scalp confers several obstacles to the reconstructive surgeon dependent upon patient-specific and wound-specific factors. We aim to describe our experiences with various reconstructive methods, and delineate risk factors for coverage failure and complications in the setting of scalp reconstruction. Methods: A retrospective chart review was conducted, examining patients who underwent resection of fungating scalp tumors with subsequent soft-tissue reconstruction from 2003 to 2019. Patient demographics, wound and oncologic characteristics, treatment modalities, and outcomes were recorded and analyzed. Results: A total of 189 patients were appropriate for inclusion, undergoing a range of reconstructive methods from skin grafting to free flaps. Thirty-three patients (17.5%) underwent preoperative radiation. In all, 48 patients (25.4%) suffered wound site complications, 25 (13.2%) underwent reoperation, and 47 (24.9%) suffered from mortality. Preoperative radiation therapy was an independent risk factor for wound complications (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.1-7.3; p=0.028) and reoperations (OR, 4.45; 95% CI, 1.5-13.2; p=0.007). Similarly, the presence of an underlying titanium mesh was an independent predictor of wound complications (OR, 2.49; 95% CI, 1.1-5.6; p=0.029) and reoperations (OR, 3.40; 95% CI, 1.2-9.7; p=0.020). Both immunosuppressed status (OR, 2.88; 95% CI, 1.2-7.1; p=0.021) and preoperative radiation therapy (OR, 3.34; 95% CI, 1.2-9.7; p=0.022) were risk factors for mortality. Conclusion: Both preoperative radiation and the presence of underlying titanium mesh are independent risk factors for wound site complications and increased reoperation rates following oncologic resection and reconstruction of the scalp. Additionally, preoperative radiation, along with an immunosuppressed state, may predict patient mortality following scalp resection and reconstruction.

• 멤브레인
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• 제16권2호
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• pp.133-143
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• 2006

방사선 그라프트 중합법을 적용하여, 폴리에틸렌 다공성 중공사막에 전자선을 조사시킨 후, glycidyl methacrylate(GMA)를 그라프트 중합하였다. 그 후, 음이온 교환기로서 diethylamine (DEA), triethylamine (TEA)를 도입시켜 2종류의 음이온 교환막을 합성하였다. DEA막과 TEA막의 이온교환 밀도는 3.4 mmol/g, 1.74 mmol/g으로 DEA막이 TEA막보다 높은 이온교환기를 얻을 수 있었다. 이 2종류의 음이온교환막에 단백질(bovine serum albumin, BSA)을 투과법에 의해 고정시켜 BSA 고정막을 만들었다. DEA-BSA막의 경우, 그라프트 체인에 BSA가 8층 이상으로 다층 흡착하였으나, TEA-BSA막의 경우, 강한 음이온에 의해 다층 흡착이 이루어지지 않았다. DEA-BSA막의 경우, BSA 다층 흡착성 고정을 나타내기 때문에 L-Trp가 D-Trp보다 더 강한 흡착 특성을 나타내었다. L, D-Trp 이성질체 혼합물을 투과시킨 BTC에 있어서, DEA-BSA 막의 경우, BSA에 대한 L-Trp와 D-Trp의 키랄 인식이 다르기 때문에 2단계의 BTC곡선을 얻을 수 있었다.

• Fibers and Polymers
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• 제4권3호
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• pp.107-113
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• 2003

The branched polypropylene (b-PP) was prepared by melt blending process with initiator, antioxidant, and functional monomers to improve the melt strength through the melt grafting. The melt flow index (MFI) of the b-PP was increased with increasing the initiator content. On the introduction of the alkylamine as the branching agents the MFI of the b-PP was increased, while that of the b-PP with the pentaerythritol triacrylate (PT) was decreased. It may be caused by the chain scission of the i-PP backbone due to the reduced thermal stability of the i-PP on the melt blending. The MFI of the b-PP without the antioxidant was increased due to the chain scission occurred during the melt processing, while on the introduction of the antioxidant, the MFI of the b-PP was decreased. The crystallization temperature of the b-PP was higher than that of PP, which was attributed to the branched chain structure. It was found that the PT was the most effective functional monomers for enhancing the melt properties of the b-PP.

• 한국잠사곤충학회지
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• 제34권1호
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• pp.49-56
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• 1992

반응개시제로 potassium persulfate를 사용하여 견섬유에 MAA를 처리하였을 때의 반응 mechanism을 구명하기 위하여, 열분석과 일련의 기구분석을 행하였으며, 이 중 열분석에 의해 얻어진 결과는 다음과 같다. Differential scanning calorimeter 관찰로부터는 metharcrylamide에 의한 가공견섬유는 견 fibroin과 methacrylamide polymer의 열분석에 의한 peak가 뚜렷하게 분리되어 나타났으며, 가공율이 증가함에 따라 두 peak가 모두 고온측으로 이동하는 것으로 나타났다. 가공견섬유의 흡습율은 가공율이 증가함에 따라 증가하였다.

• Archives of Plastic Surgery
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• 제42권5호
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• pp.601-607
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• 2015

Background Autologous or implant-based breast reconstruction after nipple-sparing mastectomy is increasingly preferred worldwide as a breast cancer treatment option. However, postoperative nipple-areola complex (NAC) necrosis is the most significant complication of nipple-sparing mastectomy. The purpose of our study was to identify the risk factors for NAC necrosis, and to describe the use of our skin-banking technique as a solution. Methods We reviewed cases of immediate autologous breast reconstruction after nipple-sparing mastectomy at our institution between June 2005 and January 2014. The patients' data were reviewed and the risk of NAC necrosis was analyzed based on correlations between patient variables and NAC necrosis. Moreover, data pertaining to five high-risk patients who underwent the donor skin-banking procedure were included in the analysis. Results Eighty-five patients underwent immediate autologous breast reconstruction after nipple-sparing mastectomy during the study period. Partial or total NAC necrosis occurred in 36 patients (43.4%). Univariate analysis and binary regression modeling found that body mass index, smoking history, radiation therapy, and mastectomy volume were significantly associated with NAC necrosis. Of the 36 cases of NAC necrosis, 31 were resolved with dressing changes, debridement, or skin grafting. The other five high-risk patients underwent our prophylactic skin-banking technique during breast reconstruction surgery. Conclusions NAC necrosis is common in patients with multiple risk factors. The use of the skin-banking technique in immediate autologous breast reconstruction is an attractive option for high-risk patients. Banked skin can be used in such cases without requiring additional donor tissue, with good results in terms of aesthetic and reconstructive outcomes.

• Archives of Plastic Surgery
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• 제44권4호
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• pp.313-318
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• 2017

Background Jeju Island is geographically and socioeconomically distinct from the mainland of South Korea. Thus, the presentation and management of non-melanocytic skin cancers (NMSC) of the head and neck may differ from those in other regions of the country. We compared the clinical characteristics and treatment modalities of NMSC on Jeju Island with the findings of similar regional studies. Methods Patient data, including age, sex, diagnosis, tumor site, treatment, and recurrence, were obtained from the medical and pathology records of patients diagnosed with NMSC between January 2010 and June 2015. Results In total, 190 patients (57 men) with a mean age of 75 years (range, 42-97) were assessed. Overall, 203 NMSCs were diagnosed, including 123 basal cell carcinomas and 80 squamous cell carcinomas. The tumor sites included the nose, cheeks, periorbital area, and lips (n=55, 54, 25, and 20, respectively). We identified 92 T1-stage and 60 T2-stage tumors, and 120 cases were treated with wide surgical resection and 17 cases were treated with radiation therapy at the medical center. Of the 120 cases treated surgically, 69 required reconstructive surgery using a local skin flap, 22 required full-thickness skin grafting, and 12 underwent primary closure. Basal and squamous cell carcinomas recurred in 2 and 1 cases, respectively. Conclusions Compared to the reports from other regions, the average patient age was 10 years higher, with a marked female preponderance. While the proportion of squamous cell carcinoma was higher than in other regions, the tumor distribution and surgical management profiles were similar.

• Journal of Chest Surgery
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• 제43권1호
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• pp.92-95
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• 2010

고위험군의 대동맥 질환 환자에서 고전적인 수술에 대한 대안책으로서 혈관내 스텐트 그라프트를 고려할 수 있다. 본원에서는 유방암에 대한 항암 방사선 치료로 인한 전 흉부 괴사와 그에 따른 상행 대동맥 파열이 발생한 79세 여자 환자에 대해 혈관내 스텐트 그라프트를 이용하여 효과적으로 치료하였기에 문헌 고찰과 함께 보고하는 바이다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권2호
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• pp.140-147
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• 2012

Microvascular reconstruction, in the oral and maxillofacial regions, is a widely accepted as the best way to overcome the complex oral cavity defects. Many patients requiring composite reconstructions have been treated previously with radiation therapy, chemotherapy, selective and/or functional neck dissection or any of these combinations. In many cases of these patients, inadequate neck vessels for the microanastomosis of free flap are available, due to a lack of recipient vessels in the neck, poor vessel quality or vessel caliber mismatch. To achieve a tension-free anastomosis, vein grafting must be considered to span the vessel gap between the free flap pedicle and the recipient neck vessels. Although most microsurgeons believed that interpositional grafts are to be avoided due to vessel thrombosis and increased number of necessary microanastomosis, we, authors have some confidence of equivalency between reconstruction with and without interpositional saphenous vein graft. The great saphenous vein, also known as the long saphenous vein, is the large subcutaneous superficial vein of the leg and thigh. It joins with the femoral vein in the region of femoral triangle at the saphenofemoral junction, and coursed medially to lie on the anterior surface of the thigh before entering an opening in the fascia lata, called the saphenous opening. For a better understanding of the great saphenous vein graft for the interpositional vessel graft in the oral cavity reconstructions, and an avoidance of any uneventful complications during these procedures, the related surgical anatomies with their harvesting tips are summarized in this review article in the Korean language.