• KSBB Journal
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• 제6권2호
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• pp.175-180
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• 1991

The quantitative effects of molecular weight and concentrations of two phase-forming polymers-polyethylene glycol and crude dextran on the two phase extractive ethanol fermentation were investigated using a Box-Wilson central composite protocol. The regression model obtained was used in order to determine optimum compositions of aqueous two phase system. In the aqueous two phase extractive ethanol fermentation of Kluyueromyces fragilis CBS 1555 with Jerusalem artichoke juice, it was found from the regression model that the variables influenlcing on ethanol fermentation were PEG concentration, time, Dx concentration, and PEG molecular weight strongly in order. The interaction of PEG concentration and PEG molecular weight was also found, and the effect of PEG concentration decreased with increase in molecular weight of PEG. The ethanol concentration incresed with increase in molecular weight of PEG, and with decrease in concentration of PEG. In conolusion, maximum concentration of ethanol produced was obtained at the following compositions; PEG MW 20000, Dx concentration ranged from 4% to 5%, and PEG concentration ranged from 3% to 7%.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2002년도 춘계공동학술대회 및 심포지움 초록집
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• pp.63-63
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• 2002

• Biomolecules & Therapeutics
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• 제17권3호
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• pp.270-275
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• 2009

Polyethylene glycol-conjugated hemoglobin (PEG-Hb) has been proposed as a blood substitute for transfusion due to their plasma expansion and oxygen transport capabilities. The protective effect of PEG-Hb on cerebral hypoxic-ischemic injury was investigated in neonatal hypoxia model and adult rat focal cerebral ischemia model. As intravenously administered 30 min before the onset of hypoxia, PEG-Hb markedly protected cerebral hypoxic injury in a neonatal rat hypoxia model. A similar treatment of PEG-Hb largely reduced the ischemic injury ensuing after 2-h middle cerebral artery occlusion followed by 22-h reperfusion. Consistently, neurological disorder was significantly improved by PEG-Hb. The results indicate that the pharmacological blockade of cerebral ischemic injury by using PEG-Hb may provide a useful strategy for the treatment of cerebral stroke.

• KSBB Journal
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• 제9권3호
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• pp.279-286
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• 1994

Fe(III) IDA -PEG/ dextran 액 이상 분계 시스템에서 phosphoprotein의 분배 예측을 위한 모델식이 유도되었다. 본 모델식에는 단백칠 분배에 수소이온과 hydroxide 이온의 저해효과가 포함되어 었다. 표변에 각각 1,27~의 phosphoryl 그 룹을 갖고 있는 ovalbumin의 AI, A2, 성분을 정제한 후 단백질 분배 실험을 수행하였으며 실 험결과와 모텔식에의한 예측이 잘 얼치하는 것 을 확인하였다. Fe(III)IDA-PEG와 단백질 표면 p phosphoryl group과의 결합상수는 PEG 상과 dextran상에 셔 각각 $6.1{\times}, 10^3M^{-1} and 2.3{\times}10^4M^{-1}$이었으며,이것은 Cu(II)IDA-PEG와 단백질 표면 histidine과의 결합상수 보다 3-5배 높은 값이 였 다.

• 약학회지
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• 제48권1호
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• pp.82-87
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• 2004

Mungbean trypsin inhibitor (MBTI) was isolated and purified from Mung bean which has been used as a galenic and traditional food. MBTI and poly(ethylene glycol) were conjugated by using water soluble carbodiimide. We evaluated the therapeutic value of the MBTI and MBTI-PEG conjugate using animal models, sublethal septic shock model in guinea pig caused by pseudomonal elastase, shock model in rat caused by lipopolysaccharide, and the vascular permeability test by using pseudomonal elastase. In two shock model in guinea p Is and in rat, hypotesion shock was inhibited by pretreatment of MBTI. And also the vascular permeability caused by pseudomonal elastase reduced by pretreatment of MBTI. Also, therapeutic value of the MBTI-PEG conjugate was evaluated by using the sublethal septic shock model caused by pseudomonal elastase. The MBTI-PEG conjugate was more effective than native MBTI against pseudomonal elastase induced septic shock in guinea pig model.

• 한국식품영양학회지
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• 제19권4호
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• pp.358-365
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• 2006

두께 1 mm의 감자 절편을 분자량 200에서 6000까지의 PEG용액에 침지했을 때 PEG의 분자량이 작을 수록 초기 탈수 속도가 빨랐으나 최종 탈수량은 PEG 분자량이 클수록 증가하여 PEG 6000인 경우 초기수분의 약 80%까지 탈수되었다. 감자절편을 저분자 용액인 NaCl, PEG400 용액에 침지한 경우, 조직의 뒤틀림 현상은 나타나지 않고 plasmolysis가 일어나면서 탈수와 부피가 감소되는 반면, PEG 600 용액에 침지시부터 조직의 뒤틀림 현상이 동반된 탈수 현상이 나타났으며, 고분자 용액인 PEG 4000 용액에 침지한 경우 cytonhysis 현상을 동반한 탈수와 부피 감소가 더욱 분명하게 관찰되었다. 초기 탈수 속도는 저분자 용액에 침지 시 더 빨랐으나 최종 탈수량은 고분자용액에 침지 시 더 컸으며 탈수량이 역전되는 시기는 cytorrhysis가 일어나는 시기와 일치하였다. 따라서 고분자 용질의 고농도 용액에 시료를 침지하면 용질의 함침량은 적게 하면서 탈수량을 증가시킬 수 있음을 알 수 있었다.

• 폴리머
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• 제32권2호
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• pp.143-149
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• 2008

생체적합성을 가진 친수성 poly(ethylene glycol)(PEG)블록과 생분해성 고분자인 Poly(D,L-lactide)(PLA) 또는 poly(lactide-co-glycolide)(PLGA)를 소수성 블록으로 하는 양친성 이중 블록공중합체를 합성하여 난용성 당뇨병 치료제인 pioglitazone의 가용화를 위한 고분자 미셀을 제조하였다. PEG 말단으로부터 LA의 개환중합에 의해 합성된 고분자의 화학적 조성과 분자량은 반응액 내 당량비로 조절하였고, 합성된 고분자는 수용액 상에서 $10{\sim}30\;nm$ 크기인 구형의 자기조립 미셀을 형성하였다($CMC=0.001{\sim}0.0076\;mg/mL$). 투석법과 고체분산법을 이용하여 약물을 봉입한 후 AFM, DLS, HPLC 분석을 통하여 미셀의 특성을 비교하였다. 결론적으로 PEG-PLA(또는 PLGA) 공중합체를 이용한 고체분산법을 통해 pioglitazone을 효과적으로 가용화시킬 수 있었다.

• 대한수의학회지
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• 제60권3호
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• pp.145-153
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• 2020

This study aimed to evaluate the effects of a bioabsorbable bone hemostatic agent comprising poly (ethylene glycol-propylene glycol) copolymers (PEG-PPG) on hemostasis and osteogenesis. Bilateral 3 mm diameter calvarial defects were created in 99 male Sprague-Dawley rats. The defects were filled with PEG-PPG or bone wax. The defects of control group were left unfilled. Virtual autopsy was performed to evaluate bioabsorption. The calvaria were subjected to x-ray microtomography (microCT) and histological examination. Bone volume fraction (BV/TV) and bone mineral density (BMD) were measured using microCT; furthermore, white blood cell count and histological examination were performed. After application of PEG-PPG and bone wax, immediate hemostasis was achieved. Autopsy revealed that PEG-PPG disappeared within 48 h at the application site; in contrast, bone wax remained until 12 weeks. The PEG-PPG and control groups showed significantly more osteogenesis than the bone wax group with respect to BV/TV and BMD at 3, 6, and 12 weeks (p < 0.05). Histology revealed that the bone wax group exhibited little bone formation with inflammation. In contrast, PEG-PPG and control groups showed significantly more qualitative osteogenesis than the bone wax group (p < 0.01). In conclusion, PEG-PPG showed immediate hemostasis and was absorbed to allow progressive osteogenesis.

• Korea-Australia Rheology Journal
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• 제17권4호
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• pp.181-190
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• 2005

Rheological characterisation of flocculated kaolinite pulps has been undertaken to elucidate particle interactions underpinning the dewatering behaviour induced by flocculation with polyethylene oxide (PEO), anionic polyacrylamide (PAM A) and their blends. Shear yield stress $(\tau_y)$ analysis indicated that polymer mediated particle interactions were markedly amplified upon shear of PEG based pulps. In contrast, PAM A based pulps showed a significant decrease in yield values upon shear. Steady stress measurements analysed using a modified Ellis model indicated subtle differences between the respective linear viscoelastic plateaus of the pulps. Furthermore, modified shear thinning behaviour was evident in PEG based pulps. Estimation of elastic and viscous moduli (G', G') was made using dynamic stress analysis for comparison with values determined from vane measurements. Despite a noticeable difference in the magnitude of G' between the two methods, similar trends indicating sheared PEG-based pulps to be more elastic than PAM based pulps, were observed. Floc microstructural observations obtained in support of rheological properties indicate that PEG flocculant induces significantly more compact particle aggregation within the clay pulps under shear consistent with the yield stress data, in contrast to PAM A, or indeed unsheared PEG based pulps. Consequentially, sheared PEG based pulps show significantly improved dewatering behaviour. The implications of the results, potential benefits and drawbacks of flocculation with PEG and PAM A are discussed with respect to improvements in current dewatering processes used in the minerals industry.

• 대한화장품학회지
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• 제43권3호
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• pp.239-245
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• 2017

노화는 생리학적으로 비가역적으로 일어나는 과정으로 노화가 진행됨에 따라 단백질의 산화화학반응 등으로 노화징후가 축적된다. 활성산소와 당화된 최종 당화산물(advanced glycation endproducts, AGEs 최종 당화산물)은 생체 조직과 세포를 공격하여 노화를 촉진한다고 알려져 있다. 본 연구에서는 항산화 물질로 알려진 aminoguanidine을 양성 대조군으로 anti-glycation 효과를 확인하였으며, methoxy PEG-45 thioctate(LA-PEG)를 농도별로 처리하여 anti-glycation 효과를 평가하였다. 실험결과 LA-PEG는 매우 우수한 anti-glycation 효과로 최종 당화산물(AGEs) 생성억제 활성이 매우 우수하게 나타났으며, 항산화 효과와 밀접한 연관을 나타냈다. 또, 세포노화 지표물질인 senescence-associated ${\beta}$-galactosidase ($SA-{\beta}-gal$) 활성을 사람 섬유아세포(HDF)를 이용하여 확인한 결과, LA-PEG를 처리하였을 때 염색된 세포의 수가 감소하여 세포의 senescence를 억제하는 것을 확인할 수 있었다. 본 연구결과, LA-PEG의 anti-glycation 효과 및 산화로 인한 단백질 손상에 대한 보호 효과가 우수하게 나타났으며, 항노화 화장품에 적용 시 효과적으로 적용할 수 있을 것으로 사료된다.