• Archives of Plastic Surgery
• /
• v.33 no.6
• /
• pp.732-736
• /
• 2006

Purpose: The purpose of this pilot study was to investigate a potential of platelet concentrate obtained from blood bank(PCBB) in accelerating wound healing and to determine an effective treatment protocol by quantifying levels of platelet derived growth factor (PDGF)-BB in PCBB in vitro. Methods: The first study was designed to investigate quantity of PDGF-BB over stored time of the PCBB. The stored times for each PCBB were 1, 3, 5, 7, 9, 11 and 13 days. The second study was designed to determine efficacy of adding thrombin to stimulate release of PDGF-BB from the platelets of PCBB. The platelets were suspended and incubated in either with or without thrombin. On 30 minutes and days 1, 3, 5, 7 after incubation, the levels of PDGF-BB were measured. Results: PDGF-BB level showed a linear decrease over stored time of PCBB from the first day to the 13th day. Addition of thrombin increased PDGF-BB release from 30 minute through the 5th day. Conclusion: The results indicate that PCBB can provide sufficient amount of growth factors to stimulate wound healing and adding thrombin accelerate it.

• Journal of Chest Surgery
• /
• v.29 no.10
• /
• pp.1160-1165
• /
• 1996

We report a case of an angiosarcoma arising from the subclavian artery, a site not previously described. A 19-year-old girl, born with a rudimentary first rib, has been suffered from arterial thoracic outlet syndrome due to a complete occlusion of the third portion of the subclavian artery for 1 year. Partial claviculectomy, excision of completely occluded arterial segment, and reconstruction with great r saphenous vein graft were done. Histologic study for the subclavlan artery revealed mural type anglosarcoma. The histochemici1 staining for factor VIII related antigen was positive. The debilitating symptoms that did not allow her a normal daily life, almost subsided postoperatively. And she has remained well with no clinical evidence of disease for 4 months post-operation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.163-166
• /
• 1997

Aluminium foam material is a highly porous material having complicated cellular structure defined by randomly distributed air pores in metallic matrix. this structure gives the aluminium a set of properties which cannot be achieved by any of conventional treatments. The properties of aluminium foam material significantly depend on its porosity, so that a desired profile of properties can be tailored by changing the foam density. Melting method is the one of foaming processes, which the production has long been considered difficult to realize becaues of such problems as the low foamability of molten metal, the varying size of. cellular structures, solidification shrinkage and so on. These problems, however, have gradually been solved by researchers and some manufacturers are now producing foamed aluminum by their own methods. Most of all, the parameters of solving problem in electric furnace were stirring temperature, stirring velocity, foaming temper:iture, and so on. But it has not considered about those in induction heating, foaming velocity and foaming temperature in semi-solid state yet. Therefore, this paper presents the effects on these parameter to control cell size, quantity and distribution.

• Journal of the Korean Electrochemical Society
• /
• v.6 no.1
• /
• pp.53-58
• /
• 2003

It is well known that the anode substrate of anode-supported type SOFC should have high electrical conductivity and high gas permeability to minimize the polarization loss of the cell performance during operation. In this study, we made anode substrates of SOFC with two different methods, which gave different anode microstructures, especially different pore structures with each other. We performed electrical and microstructural characterization of Ni/YSZ cermet anode via extensive measurements of its electrical conductivity and gas permeability combined with adequate image analysis based on quantitative stereological theory

• Archives of Plastic Surgery
• /
• v.37 no.1
• /
• pp.7-11
• /
• 2010

Purpose: Vascular endothelial growth factor (VEGF) is known as a growth factor of endothelium and fibroblast. The purpose is to know the VEGF effects on fibroblast proliferation and fibroblast's notch receptor expression. Methods: CCD-986sk fibroblast was purchased from the Korean Cell Bank and was used in XTT assay for proliferation and wound healing assay for migration. Immunofluorescent (IF) staining and western blotting were used in testing notch expression of fibroblast. Semiquantitative RT-PCR was used in checking notch 1 mRNA production by fibroblast. Student-t test was used for analyzing results. Results: Cell proliferation assay using XTT showed significant higher proliferation in VEGF treated fibroblast, $2.324{\pm}0.0026$ vs. $2.463{\pm}0.017$ (p=0.002). Wound healing assay showed longer migration in VEGF treated fibroblast (p=0.062). The fluorescence was brighter in VEGF treated cells of notch 1 IF staining. Notch 1 expressions and mRNA productions increased more in VEGF treated cells. Conclusion: VEGF stimulates fibroblast to proliferate, migrate and to express Notch 1 simultaneously. Notch receptor could be related to VEGF mediated wound healing.

• Archives of Plastic Surgery
• /
• v.36 no.6
• /
• pp.792-794
• /
• 2009

Purpose: Clotting factor X deficiency is one of the most uncommon coagulation disorders. The authors describe a case of cleft palate in a patient with a congenital clotting factor X deficiency. Methods: In pediatric patients with a cleft palate, the coagulation problem is more worrisome, because they are more sensitive to blood than adults, and because postoperative bleeding can cause blood ingestion with subsequent vomiting, aspiration, and airway obstruction. To prevent hemorrhagic complications in the described case, fresh frozen plasma (FFP) was administered every 24 hrs from the day before surgery to the second postoperative day. Results: Good hemostasis, normal healing, and no complications was shown postoperatively. Conclusion: The replacement of fresh frozen plasma was useful in the case of congenital clotting factor deficiency for bleeding prophylaxis in cleft palate operation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2005.10a
• /
• pp.87-90
• /
• 2005

The drawbead is used to control the material flow into the die and increase the forming quality during the binder wrap process and the stamping process in the sheet metal forming. Drawbead restraining force (DBRF) is controlled by geometrical parameters and influenced by process parameters such as friction coefficient and blank thickness. In order to inspect the effect of process parameters, parameter studies are performed with the variation of parameters using finite element model of drawbead which is utilized reliably for the calculation of the drawbead restraining force. Drawbead analysis is carried out with 2-D plane-strain element and 3-D shell element. After the verification of the accuracy of the drawbead model with 3-D shell element, it is utilized to the prediction and the investigation of the effect of process parameters. The result of parameter studies can be utilized to the die design in the tryout stage.

• Journal of the Korean Geotechnical Society
• /
• v.17 no.4
• /
• pp.57-70
• /
• 2001

한계상태이론은 정규압밀 및 과압밀시료에 대한 비배수 전단강도와 간극수압계수에 관한 식을 제안하고 있는데, 이 식은 3가지 상수를 포함하고 있다. 한계상태상수(M), 한계상태 간격비(${\gamma}$), 한계상태 간극수압계수(Λ)가 바로 그것이며, 이러한 상수는 각 모델 및 구하는 방법에 따라 그 차이가 발생함으로서, 전단강도 및 간극수압계수의 예측시 적지 않은 영향을 미치게 된다. 본 논문에서는 재 성형된 이암풍화토를 이용하여 등방삼축압축시험을 정규압밀과 과압밀로 나누어 실시하고 그 결과를 분석하였으며 이를 토대로 각 모델 및 방법에 따른 상수를 도출하였다. 그리고 이러한 상수의 차이가 비배수 전단강도 및 간극수압계수의 예측에 미치는 영향을 살펴보았다. 시험결과 정규압밀시료의 경우 각 상수의 변화에 따른 비배수 전단강도 및 간극수압계수는 상당한 차이를 보였으며, 한계상태간격비와 Λ값을 강도비로부터 얻어진 값을 사용한 경우가 결과치에 가장 잘 근접함을 알 수 있었다. 과압밀시료의 경우 역시 이들 상수에 따라 전단강도의 변화폭이 크게 나타났으며 정규압밀과 마찬가지로 강도비에서부터 도출된 상수를 적요한 경우 실측치에 가장 근접하였다. 반면 간극수압계수의 예측시에는 상수에 따른 변화폭이 크지 않았으며, 특히 과압밀비가 증가할수록 각 상수에 대한 영향이 작게 나타났다.

• Fashion & Textile Research Journal
• /
• v.22 no.4
• /
• pp.515-522
• /
• 2020

This study examined the effect of the blend ratio of wool and polyester fibers, yarn and fabric structural parameters to the appearance property and the formability of worsted fabrics. The mechanical properties of twenty types of manufactured worsted and PET/wool blend fabrics were measured using KES-FB and FAST systems. Garment formability increases with the thickness and cover factor as well as increases with wool content. The correlation between KES-FB and FAST system showed a relatively high correlation with an extensibility of 0.98, bending and shear rigidity 0.71; both were higher than polyester synthetic fiber. The correlation coefficient of garment formability between KES-FB and FAST systems was 0.93 and the correlation coefficient between formability and fabric extensibility was 0.8. These results were higher than those of bending and shear rigidity. This revealed that garment formability was influenced by wool content, cover factor and fabric thickness; however, wool content and fabric thickness were the most important factors for the seam pucker. The garment formability of the worsted fabrics can be predicted by fabric mechanical properties measured from KES-FB and FAST systems.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.31 no.1
• /
• pp.8-17
• /
• 2009

Purpose: We determined the therapeutic effect of an epidermal growth factor receptor (EGFR)-specific monoclonal antibody (mAb), cetuximab (Erbitux) on the growth of oral squamous cell carcinoma (OSCC) xenografted in athymic nude mice. Experimental Design: We induced subcutaneous tumors by inoculating human tumor cell suspension into the right flank of nude mice. Nude mice with subcutaneous tumors were randomized to receive cetuximab alone, paclitaxel alone, cetuximab plus paclitaxel, or a placebo (control). Antitumor mechanisms of cetuximab were determined by immunohistochemical and apoptosis assays. Results: Cetuximab, paclitaxel, and cetuximab/paclitaxel combined therapy resulted in 50%, 52%, 67% in vivo inhibition of tumor proliferation, respectively. Tumors of mice treated with cetuximab plus paclitaxel demonstrated decreased PCNA-positive tumor cells and increased apoptotic tumor cells, which slowed growth of the murine tumors. Conclusion: These data show that EGFR can be a molecular target for the treatment of OSCC. And combination therapy with cetuximab and paclitaxel warrants further clinical study.