RESEARCH PAPER : Docetaxel-Loaded Thermosensitive and Bioadhesive Nanomicelles as a Rectal Drug Delivery System for Enhanced Chemotherapeutic Effect

( Youn Gee Seo ),( Dong Wuk Kim ),( Woo Hyun Yeo ),( Thiruganesh Ramasamy ),( Yu Kyoung Oh ),( Young Joon Park ),( Jung Ae Kim ),( Dong Hoon Oh ),( Sae Kwang Ku ),( Jin Ki Kim ),( Chul Soon Yong ),( J 영남대학교 약품개발연구소 2013 영남대학교 약품개발연구소 연구업적집 Vol.23 No.0

PURPOSE: To investigate the potential of thermosensitive and biadhesive nanomicelles in improving the bioavailability of docetaxel (DCT) and its chemotherapeutic effect. METHOD: DCT-loaded nanomicelles were prepared by emulsufication and characterized in terms of physico-chemical and visco-elastic parameters. The optimzed formulation was evaluated for in vivo localization, pharmacokinetic and anti-tumor efficacy. RESULTS: The hydrodynamic size of DCT-loaded nanomicelles was approximately 13 nm and thenanomicelles exhibited a sufficient gelation strength (9250 mPa·s) and bioadhesive force (2100 dyn/cm²) to be retained in the upper part of rectum. We observed a high rectal bioavailability of 29% DCT compared to that following oral administration in rats, as it successfully evaded the multidrug efflux transporters and hepatic first-pass metabolism. Plasma concentration around ∼50 ng/mL was maintained throughout the study period (12 h) while Taxotere® attained subtherapeutic range within 4 h of drug administration. Results also revealed that the rectally administered DCT-loaded nanomicellesexhibited a significant anti-tumor effect (200 mm³) with a reduced toxicity profile when compared to orally administered DCT (950 mm³). Furthermore, histological study showed that the rectal mucosa was completely intact with no signs of irritation upon treatment with DCT-loaded nanomicelles. CONCLUSIONS: Taken together, our novel thermosensitive and biadhesive nanomicellesdemonstrated the ability to improve the bioavailability and chemotherapeutic potential of DCT in vivo. To the best of our knowledge, this is the first report describing the rectal delivery of DCT-loaded nanomicelles.

Development of docetaxel-loaded solid self-nanoemulsifying drug delivery system (SNEDDS) for enhanced chemotherapeutic effect

( Youn Gee Seo ),( Dae Hwan Kim ),( Thiruganesh Ramasamy ),( Jeong Hwan Kim ),( Nirmal Marasini ),( Yu Kyoung Oh ),( Dong Wuk Kim ),( Jin Ki Kim ),( Chul Soon Yong ),( Jong Oh Kim ),( Han Gon Choi ) 영남대학교 약품개발연구소 2013 영남대학교 약품개발연구소 연구업적집 Vol.23 No.0

The main purpose of this study was to investigate the potential of self-nano-emulsifying drug delivery system (SNEDDS) in improving the bioavailability of docetaxel (DCT) and its chemotherapeutic effect. The DCT-loaded SNEDDS was prepared by employing rational blends of capryol 90, labrasol, and transcutol HP using ternary phase diagram. The liquid nano-emulsion was spray-dried into solid SNEDDS (D-SNEDDS) using an inert porous carrier, colloidal silica. The optimized formulation was characterized in terms of physico-chemical and pharmacokinetic parameters. Furthermore, anti-tumor efficacy of D-SNEDDS was compared with commercial marketed product, Taxotere(®). The various compositions of SNEDDS were screened and found optimal at a volume ratio of 10/75/15 for capryol 90, labrasol, and transcutol HP, respectively. We observed a high oral bioavailability of 17% DCT for D-SNEDDS than compared to only 2.6% for pure DCT solution. Notably, D-SNEDDS exhibited an augmented anti-tumor efficacy with a reduced toxicity profile when compared with intravenously administered Taxotere(®), the commercialized formulation of DCT. Taken together, D-SNEDDS could be a potential candidate for an oral dosage form of DCT with enhanced antitumor activity and reduced toxicity. ⓒ2013 ELsevier B. B. All rights reserved.

Improving Building Evacuation Systems for Elderly through User Centered Design: A Case Study Based on Agent-based Simulation

Huamin Jin,Sung Hee Ahn,Min Kyu Choi,Yu Shin Lee,Gee Won Shin,Myung Hwan Yun 대한인간공학회 2018 대한인간공학회 학술대회논문집 Vol.2018 No.5

AR모델과 MLP를 이용한 단기 물 수요 예측 알고리즘 개발

최기선(Gee-Seon Choi),유철(Chool Yu),진력민(Ryuk-Min Jin),유성근(Seong-Keun Yu),전명근(Myung-Geun Chun) 한국지능시스템학회 2009 한국지능시스템학회논문지 Vol.19 No.5

본 논문은 비선형 특성을 내재한 물 수요예측을 위하여 기존의 시계열 자기회귀 알고리즘과 다층신경망 학습방법을 결합한 단기 물 수요 예측 알고리즘을 개발하였다. 제시된 방법을 검증하기 위한 사례연구로 2007년도와 2008년도 전북지역의 광역상수도 A정수장에서 취득된 데이터를 활용하여 알고리즘 구축 및 제안 방법의 정확도를 분석하였다. 실험 결과 다중 회귀모델은 MAPE가 5.1%, AR모델은 3.8%, 제안된 방법인 AR+MLP 모델은 3.6%로 나타나 성능이 우수한 것으로 나타났다. 따라서 제안된 방법을 사용할 경우 정수장에서 단기 물 수요예측에 유용하게 활용할 수 있음을 보였다. In this paper, we develope a water demand forecasting algorithm using AR(Auto-regressive) and MLP(Multi-layer perceptron). To show effectiveness of the proposed method, we analyzed characteristics of time-series data collected in "A" purification plant at Jeon-Buk province during 2007-2008, and then performed the proposed method with various input factors selected through various analyses. As noted in experimental results, the performance of three types model such as multi-regressive, AR(Auto-regressive), and AR+MLP(Auto-regressive + Multi-layer perceptron) show 5.1%, 3.8%, and 3.6% with respect to MAPE(Mean Absolute Percentage Error), respectively. Thus, it is noted that the proposed method can be used to predict short-term water demand for the efficient operation of a water purification plant.

Ophthalmologic Findings of Boucher-Neuhauser Syndrome

( Sun Im Yu ),( Jung Lim Kim ),( Sul Gee Lee ),( Hyun Woong Kim ),( Sang Jin Kim ) 대한안과학회 2008 Korean Journal of Ophthalmology Vol.22 No.4

To report a case of Boucher-Neuhauser syndrome, which is an autosomal recessive disorder characterized by the triad of spinocerebellar ataxia, chorioretinal dystrophy, and hypogonadotropic hypogonadism. An 18-year-old man was seen for visual problems, which had been diagnosed as retinitis pigmentosa at the age of 12 years. His puberty was delayed. At 16 years of age, the patient experienced progressive deterioration of his balance and gait disturbance. Then he was referred to our clinic because Boucher-Neuhauser syndrome was suspected. He had no specific family history; his visual acuity was 0.04 in both eyes. We observed broad retinal pigment epithelium atrophy and degeneration in both fundi. Both fluorescein and indocyanine green angiography showed choriocapillaris atrophy in the posterior pole area and midperiphery. Macular optical coherence tomography showed thinning of the neurosensory retina. An electroretinographic examination showed no photopic or scotopic responses. The Boucher-Neuhauser syndrome should be included in the differential diagnosis of patients with retinitis pigment epithelium atrophy and degeneration. Korean J Ophthalmol 2008;22:263-267

Ophthalmologic Findings of Boucher-Neuhäuser Syndrome

Sun Im Yu,Jung Lim Kim,Sul Gee Lee,Hyun Woong Kim,Sang Jin Kim 대한안과학회 2009 Korean Journal of Ophthalmology Vol.23 No.1

To report a case of Boucher-Neuhäuser syndrome, which is an autosomal recessive disorder characterized by the triad of spinocerebellar ataxia, chorioretinal dystrophy, and hypogonadotropic hypogonadism. An 18-year-old man was seen for visual problems, which had been diagnosed as retinitis pigmentosa at the age of 12 years. His puberty was delayed. At 16 years of age, the patient experienced progressive deterioration of his balance and gait disturbance. Then he was referred to our clinic because Boucher-Neuhäuser syndrome was suspected. He had no specific family history; his visual acuity was 0.04 in both eyes. We observed broad retinal pigment epithelium atrophy and degeneration in both fundi. Both fluorescein and indocyanine green angiography showed choriocapillaris atrophy in the posterior pole area and midperiphery. Macular optical coherence tomography showed thinning of the neurosensory retina. An electroretinographic examination showed no photopic or scotopic responses. The Boucher-Neuhäuser syndrome should be included in the differential diagnosis of patients with retinitis pigment epithelium atrophy and degeneration.

이차원 학업적 의지통제 척도의 개발 및 타당화

박병기(Byung Gee Bak),유경미(Kyoung Mi Yu),김진아(Jin A Kim),김경희(Kyoung Hee Kim) 한국교육심리학회 2011 敎育心理硏究 Vol.25 No.1

이 연구의 목적은 학업적 의지통제 척도를 개발하고 타당화하는 것이었다. 연구대상은 2개 초등학교 6학년 458명과 1개 중학교 2학년 학생 227명, 총 685명이었다. 초등학생 458명은 무선적으로 양분하여 225명은 탐색집단으로, 나머지 233명은 교차집단으로 활용하였다. 중학생 227명은 모두 교차집단으로 활용하였다. 학업적 의지통제 척도는 두 개의 의지통제 시기와 여섯 개의 의지통제 내용이 교차하는 2×6 이차원 개념구조에 근거하여 개발되었다. 의지통제 시기는 착수와 유지를 포함하며, 의지통제 내용은 효능고양, 흥미증진, 필요강조 등 세 종류의 동기통제와 정서고취, 평상회복, 경계유발 등 세 종류의 정서통제를 포함한다. 이 연구에서 개발된 이차원 학업적 의지통제 척도 AVCS의 타당화는 크게 세 단계를 거쳤다. 첫 단계에서는 척도의 문항특성을 검토하여 적합한 문항을 선별하는 것이다. 문항특성의 적합성은 반응경향, 신뢰도, 일차원성 등을 검토하여 판단하였는데, 제거할만한 문항은 발견되지 않았다. 둘째 단계에서는 다변량 자료에서 중요하게 고려해야 할 적당한 관계성 가정이 만족되는지 검토하는 것이다. 상관행렬과 VIF지수를 검토한 결과 적당한 관계성 가정은 큰 무리 없이 만족되었다. 단, 다른 시기의 동일한 의지통제 내용 간에 다소 높은 상관계수가 나타나 향후 척도활용의 다양성을 시사하였다. 셋째 단계에서는 구인타당도, 준거타당도, 교차타당도 등 세 가지 종류의 타당도 정보를 검토하는 것이었다. 구인타당도는 측정모형과 구조모형의 두 측면에서 검토하였다. 요인계수, 결정계수, 적합도 정보를 종합하였을 때 12개 구성요인의 측정모형은 적합하였으며, 두 개 경쟁모형과의 비교를 통해 볼 때 2x6 요인구조 모형의 적합성도 지지되었다. 자기조절학습 및 목표지향성과의 상관행렬을 분석한 결과 AVCS의 준거타당도는 양호하였다. 두 개의 교차집단을 대상으로 한 교차타당도 분석결과 AVCS는 안정성과 일반화가능성에 있어서 양호하였다. 연구결과에서 드러난 다양한 정보에 근거하여 학업적 의지통제 척도 AVCS의 향후 전망이 논의되었다. The purpose of this study was to develop and validate a two dimensional scale of academic volitional control. Subjects included 458 elementary students and 227 middle school students. One half of the elementary students were randomly assigned to an exploratory group, and the other half elementary students and the middle school students were utilized as cross-validation groups. AVCS(Academic Volitional Control Scale) developed in this study consisted of 2×6 factor structure: 6 volitional contents of efficacy enhancement, interest enhancement, necessity emphasis, emotion inspiration, normal recovery, and warning induction, and 2 control periods of starting and persistence. Total 48 items of 12 sub-constructs were good in terms of item response pattern, internal consistency, and uni-dimensionality. Construct validity was supported from the confirmatory factor analysis. The measurement model and the factor structure model of AVCS were fully acceptable. Criterion validity with self-regulated learning and achievement goal orientation was highly supported. Cross-validation into two groups displays that the AVCS is stable and generalizable. Significance and future perspective of the research on academic volitional control were discussed.

Development of a novel sodium fusidate-loaded triple polymer hydrogel wound: Mechanical properties and effects on wound repair

( Sung Guy Jin ),( Kyeong Soo Kim ),( Dong Wuk Kim ),( Dong Shik Kim ),( Youn Gee Seo ),( Toe Gyung Go ),( Yu Seok Youn ),( Jong Oh Kim ),( Chul Soon Yong ),( Han Gon Choi ) 영남대학교 약품개발연구소 2016 영남대학교 약품개발연구소 연구업적집 Vol.26 No.-

To develop a novel sodium fusidate-Ioaded triple polymer hydrogel dressing (TPHD). numerious polyvinyl alcohol-based (PVA) hydrogel dressings were prepared with various hydrophilic polymers using the freeze-thaw method. and their hydrogel dressing properties were assessed. Among the hydrophilic polymers tested, sodium alginate (SA) improved the swelling capacity the most, and polyvinyl pyrrolidone (PVP) provided the greatest improvement in bioadhesive stength and mechanical properties. Thus, PVA based-TPHDs were prepared using different ratios of PVP:SA The effect of selected PVP:SA ratios on the swelling capacity, bioadhesive strength, mechanical properties, and drug release, permeation and deposition characteristics of sodium fusidate-Ioaded PVA-based TPHDs were assessed. As the ratio of PVP:SA increased in PVA-Ioaded TPHD, the swelling capacity, mechanical properties, drug release. permeation and deposition were improved. The TPHD containing PVA. PVP, SA and sodium fusidate at the weight ratio of 10/6/1/1 showed excellent hydrogel dressing properties. release. permeation and deposition of drug. Within 24 h, 71.8 ± 1.3% of drug was released. It permeated 625.1 ±81.2μg/cm₂ through the skin and deposited of 313.8 ± 24.1 fLgfcm2 within 24 h. The results of in vivo pharmacodynamic studies showed that sodium fusidate-Ioaded TPHD was more effective in improving the repair process than was a commercial product. Thus, this sodium fusidate-Ioaded TPHD could be a novel tool in wound care.

Application of Robotic Welding Technology to the Continuity Plate Weld Within a Steel Built-up Box Column in Buildings

Chung-Che Chou,Gee‑Jin Yu,Kung‑Juin Wang,Wei‑Tze Chang,Chiun‑Lin Wu,Charlene Chin‑Jie Zhao,Chun‑Yao Yang,Ming‑Ti Chou 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.9

This paper presents a study to investigate the feasibility of using robotic welding technologies to weld the continuity plate and the column flange plate during manufacturing steel built-up box columns in buildings. Specimens designed to emulate the key components in the steel beam-to-column moment connections for Special moment frame were fabricated and welded using a proposed automated procedure that performs multi-layer, multi-pass welding for thick steel plates. Effects of controlling parameters on robotic welding results that includes the manner of bead stacking, wire feed speed, travel speed, working angle, arc voltage, the path of the welding pass, and the methods to start and finish welding passes were investigated. The quality of the welded products was assessed by visual inspection and ultrasonic testing (UT). Further mechanical tests including tensile tests, bending tests, and cyclic loading tests were carried out on selected welded products that passed the UT examination. The test results indicated that the robotic welds showed no visible damage or cracks, met requirements specified in the AWS specification, and exhibited satisfactory strength and ductility.

전단보강에 따른 일방향 중공슬래브의 휨 성능 평가

유유진,석근영,김기철,강주원,Yu, Yu-Jin,Seok, Keun-Young,Kim, Gee-Cheol,Kang, Joo-Won 한국공간구조학회 2014 한국공간구조학회지 Vol.14 No.2

The purpose of this study is intended to determine the validity of shear reinforcement by evaluating flexural performance in the hollow slab. The hollow slab is relatively light and second moment of inertia is large. Due to these characteristics, it can be used to slab system efficiently. Therefore the prediction of the structural behaviors is very important because of decrease of shear and flexural strength which is caused by hollow section of slab interior. In this study, the flexural test were performed to analyze the flexural capacity of the hollow slab w/ or w/o shear reinforcement. A total of six full scale specimens were tested. These specimens have three cases of reinforcing bar ratio, 0.009, 0.018 and 0.024. To verify the flexural behavior such as ultimate load, load-deflection and crack pattern, the flexural experiment were tested by using loading frame. Experimental results have shown that the flexural behavior are depend on the reinforcing bar ratio. Also the hollow slab with shear reinforcement have shown flexural behavior. Therefore, it is appropriate that the hollow slab is reinforced by shear reinforcement to improve the flexural performance of the hollow slab.