전신성 흥반성 낭창에서의 생존율에 관한 연구

한지숙,박금수,조철호,고윤웅,윤진우,전상일 대한내과학회 1986 대한내과학회지 Vol.30 No.1

We retrospectively analyzed clinical and laboratory features of 58 patients with SLE for the survival and the factors which may have influenced the outcome from 1970 through 1983. The survival was calculated using the method of Merill and Shulman, taking the time of diagnosis and the onset of symptom as the starting point. We divided 58 patients with SLE into 2 groups, those whose survival was less than or equal to 2 years and those greater than 2 years, and compared clinical and laboratory features between them with particular emphasis on those factors which may have influenced the outcome. The results obtained as follows: 1) The estimated survival from diagnosis was 76.7% in 1 year, 62.3% in 2 years, 62.3% in 3 years, 59.6% in 4 years, 53.8% in 5 years and 50.6% in 10 years. The estimated survival from the onset of symptom was 65.5%, in 1 years, 59.54% in 2 years, 56.2% in 3 years, 52.2% in 4 years, 52.5% in 5 years, and 46.l% in 10 years. 2) There was a statisticaly significant difference in prognosis between 2 groups with regard to CNS involvement, serositis, and increased serum creatinine level(≥3.0mg/dl).

만성 신부전증 환자의 중중 고혈당에 따른 의식 변화 결정에 대한 연구

위형중,이창범,박성광,강성귀,임천규,박은주,윤경택,한상웅,안유헌,김호중· 대한신장학회 2000 대한신장학회잡지 Vol.19 No.6

Preparation and in vitro/in vivo evaluation of PLGA microspheres containing norquetiapine for long-acting injection

Park, Chun-Woong,Lee, Hyo-Jung,Oh, Dong-Won,Kang, Ji-Hyun,Han, Chang-Soo,Kim, Dong-Wook Dove Medical Press 2018 Drug design, development and therapy Vol.12 No.-

<P><B>Background</B></P><P>Norquetiapine (<I>N</I>-desalkyl quetiapine, NQ) is an active metabolite of quetiapine with stable pharmacokinetic and pharmacological properties. However, its short half-life is a drawback for clinical applications, and long-acting formulations are required.</P><P><B>Purpose</B></P><P>The objectives of this study were to prepare improved entrapment efficiency NQ freebase microspheres by the solvent evaporation method with poly(d,l-lactic-co-glycolic acid) (PLGA) as a release modulator and to evaluate their physicochemical and in vitro/in vivo release properties.</P><P><B>Methods</B></P><P>NQ freebase PLGA (1:5 w/w) formulations were prepared by the oil-in-water (o/w) emulsion–solvent evaporation method. A solution of the drug and PLGA in 9:1 v/v dichloromethane:ethanol was mixed with 0.2% polyvinyl alcohol and homogenized at 2,800 rpm. The emulsion was stirred for 3 h to dilute and evaporate the solvent. After that, the resulting product was freeze-dried. Drug-loading capacity was measured by the validated RP-HPLC method. The surface morphology of the microspheres was observed by scanning electron microscopy (SEM), and the physicochemical properties were evaluated by differential scanning calorimetry, powder X-ray diffraction, and Fourier-transform infrared spectroscopy particle size distribution. The in vitro dissolution test was performed using a rotary shaking bath at 37°C, with constant shaking at 50 rpm in sink condition.</P><P><B>Results</B></P><P>The NQ freebase microspheres prepared by o/w emulsion-solvent evaporation showed over 30% efficiency. NQ was confirmed to be amorphous in the microspheres by powder X-ray diffraction and differential scanning calorimetry. Special chemical interaction in the microspheres was not observed by FT-IR. The in vitro dissolution test demonstrated that the prepared microspheres’ release properties were maintained for more than 20 days. The in vivo test also confirmed that the particles’ long acting properties were maintained. Therefore, good in vitro–in vivo correlation was established.</P><P><B>Conclusion</B></P><P>In this study, NQ freebase-PLGA microspheres showed potential for the treatment of schizophrenia for long-periods.</P>

Snail Extract Ameliorates Loperamide-induced Constipation in Rats

Chun Woong Park,Yejin Ahn,Hoon Kim,Hyung Joo Suh 한국식품영양과학회 2022 한국식품영양과학회 학술대회발표집 Vol.2022 No.10

De-soda Process Using Silica for Fabrication of Low Soda Alumina Powder

Park, Sang-Chun,Kim, Dae-Woong,Heo, In-Woong,Lee, Sang-Jin The Korean Ceramic Society 2015 한국세라믹학회지 Vol.52 No.3

Low soda alumina powder was fabricated using silica (${\alpha}$-quartz) as an agent for removing soda components in the alumina. Quartz powder 2 mm in size was added to aluminum hydroxide obtained through the Bayer process, and then the mixture was heated at various temperatures. Finally, the heat-treated powders were sieved for classification. In this study, the effects of the quartz amount and heating temperature on the mechanism of removing soda were examined. A minimum soda content of 0.005 wt% was observed at the conditions of 15 wt% quartz (based on $Al(OH)_3$ amount) heat-treated at $1600^{\circ}C$ for 8 h. The soda components, such as $Na_2O$, NaOH, and $Na_2CO_3$, in alumina were ionized and activated at high temperature, and this facilitated the reaction with quartz silica and alumina producing nepheline. The advantages of using quartz include low iron content and low cost in comparison with the conventional de-soda process using chamotte, another silicate mineral.

Reduction of ambipolar characteristics of vertical channel tunneling field-effect transistor by using dielectric sidewall

Park, Chun Woong,Choi, Woo Young,Lee, Jong-Ho,Cho, Il Hwan Institute of Physics 2013 Semiconductor science and technology Vol.28 No.11

<P>Ambipolar characteristics of tunneling FETs have been improved by introducing a novel structure which contains dielectric sidewall in the gate region. In the ambipolar operation mode, gate field effect on intrinsic-drain junction region can be reduced with dielectric sidewall. As a result, ambipolar state tunneling probability is decreased at the intrinsic-drain junction. Since the sidewall region is located near the drain region, tunneling probability of source-intrinsic region is not affected by dielectric sidewall. This asymmetric characteristics means only ambipolar current of tunneling FETs can be prohibited by dielectric sidewall. Reduction of ambipolar characteristic of proposed structure has been evaluated with dimension and location of dielectric sidewall. Quantitative analysis of ambipolar characteristics is also investigated with tunneling.</P>

Scaling Down Characteristics of Vertical Channel Phase Change Random Access Memory (VPCRAM)

Park, Chun Woong,Park, Chongdae,Choi, Woo Young,Seo, Dongsun,Jeong, Cherlhyun,Cho, Il Hwan The Institute of Electronics and Information Engin 2014 Journal of semiconductor technology and science Vol.14 No.1

In this paper, scaling down characteristics of vertical channel phase random access memory are investigated with device simulator and finite element analysis simulator. Electrical properties of select transistor are obtained by device simulator and those of phase change material are obtained by finite element analysis simulator. From the fusion of both data, scaling properties of vertical channel phase change random access memory (VPCRAM) are considered with ITRS roadmap. Simulation of set reset current are carried out to analyze the feasibility of scaling down and compared with values in ITRS roadmap. Simulation results show that width and length ratio of the phase change material (PCM) is key parameter of scaling down in VPCRAM. Thermal simulation results provide the design guideline of VPCRAM. Optimization of phase change material in VPCRAM can be achieved by oxide sidewall process optimization.

Fitness cost and competitive ability of transgenic herbicide-tolerant rice expressing a protoporphyrinogen oxidase gene

Chun, Young Jin,Kim, Dae In,Park, Kee Woong,Jeong, Soon-Chun,Park, Sangkyu,Back, Kyoungwhan,Kim, Chang-Gi The Ecological Society of Korea 2013 Journal of Ecology and Environment Vol.36 No.1

The expression of transgenic traits in genetically modified crops is sometimes associated with decreases in crop performance or fitness. These decreases in performance or fitness of transgenic plants in unfavourable conditions may provide valuable information about the ecological consequences of transgene escape. In a glasshouse trial, we tested the cost associated with resistance to herbicides by comparing the growth, yield, and competitive ability of transgenic rice with its parental non-transgenic line. This new line was developed for constitutive overexpression of protoporphyrinogen oxidase (PPO) to increase resistance to herbicides. We evaluated nine agronomic traits of transgenic and non-transgenic rice grown in a replacement series design over four densities. Competitive ability was also assessed between transgenic and non-transgenic plants by analyzing their relative yields based on biomass and seed weight data. Our results indicated that non-transgenic plants showed greater performance than did the transgenic plants when those genotypes were grown in mixtures. The non-transgenic rice plants exhibited superior competitive ability at certain combinations of planting densities and genotype proportions. These results suggest that PPO-herbicide resistance incurs some costs in plant performance and competitive ability.

Comparative study on mechanical behavior of low temperature application materials for ships and offshore structures: Part II – Constitutive model

Park, Woong-Sup,Lee, Chi-Seung,Chun, Min-Sung,Kim, Myung-Hyun,Lee, Jae-Myung Elsevier 2011 Materials science & engineering. properties, micro Vol.528 No.25

<P><B>Highlights</B></P><P>• A modified constitutive model for the behaviors of cryogenic material is presented. • A novel material parameter identification method is suggested. • A damage model is applied to the proposed model for a description of material failure. • Test results suggested in a previous study are simulated using the proposed method.</P> <P><B>Abstract</B></P><P>Austenitic stainless steel (ASS), aluminum alloy, and nickel steel alloy are strong temperature- and strain-rate-dependent materials. They exhibit very complicated nonlinear behaviors during plastic deformation. While the typical characteristics of their nonlinear behaviors, including second hardening and strain-rate sensitivity, can be easily identified through experimental investigation, a useful numerical model is not available. The unavailability of such a model is because of the wide variance in the nonlinearities of the materials. In the present study, a unified constitutive model is proposed for representing the temperature- and strain-rate-dependent material nonlinearities in ASS and aluminum and nickel steel alloys. Based on the Bodner model, a strain-hardening function was developed for expressing second hardening as well as strain-rate sensitivity. To provide unified material parameters for the hardening exponent and strain-rate control, a new type of material parameter identification method is proposed. Based on the proposed constitutive model, in conjunction with both a damage model and the material parameters, a verification study is conducted. The experimental results of both Park et al. <ce:cross-ref refid='bib0005'>[1]</ce:cross-ref> and Tomita and Iwamoto <ce:cross-ref refid='bib0010'>[2]</ce:cross-ref>, which are valid within a temperature range of 80–345K and a strain-rate range of 0.0005–500/s, are compared with the numerical results of this study.</P>

Preparation and in vivo evaluation of immediate-release pellet containing celecoxib solid dispersion

Park, Chun-Woong,Tung, Nguyen-Thach,Son, Dao-Danh,Kim, Ju-Young,Rhee, Yun-Seok,Kang, Seung-Yeop,Park, Shin-Ae,Hwang, Kyu-Mok,Oh, Tack-Oon,Ha, Jung-Myung,Chi, Sang-Cheol,Park, Eun-Seok 한국약제학회 2012 Journal of Pharmaceutical Investigation Vol.42 No.3

The aim of this study was to make use of small size of immediate-release (IR) pellet and amorphous state of solid dispersion to increase solubility of celecoxib (CLX), a drug in BCS class II. Primary, binary and ternary solid dispersions were developed to choose the final components for solid dispersion. A ternary novel solid dispersion was prepared by incorporation of one aqueous soluble polymer (povidone k17; PVP 17PF), Methacrylate copolymer-based gastric soluble polymer ($Eudragit^{(R)}$ EPO) and one pH modulator (MgO). This combination was effective to increase solubility in pH 1.2 up to 25-30 %. The mechanism of solubility enhancement was proven by DSC, PRXD, and FT-IR. Accordingly, hydrogen bonding or electrostatic interaction of CLX with PVP/$Eudragit^{(R)}$ EPO was the main cause to form the amorphous state of CLX within polymer cluster which increasing solubility of drug. Besides, MgO played an important role to change microenviroment for solid dispersion. Pellets containing this solid dispersion were prepared by extrusion and spheronization technique. Effect of four kinds of additive (calcium hydrogen phosphate dihydrate,$NaHCO_3$, crospovidone, and sodium dodecyl sulfate) on dissolution of CLX from IR pellet was also determined. Because of highest dissolution rate, formulation using sodium dodecyl sulfate was used for pharmacokinetics study. Solid dispersion-IR pellet formulation presented bioequivalence and lower variability in comparison with reference product.