• Molecules and Cells
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• 제20권2호
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• pp.173-182
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• 2005

Heat shock protein gp96 is an endoplasmic reticulum chaperone, belonging to the HSP90 family. The function of gp96 as a molecular chaperone was discovered more than 10 years ago, but its importance has been overshadowed by the brilliance of its role in immune responses. It is now clear that gp96 is instrumental in the initiation of both the innate and adaptive immunity. Recently, the roles of gp96 in protein homeostasis, as well as in cell differentiation and development, are beginning to draw more attention due to rapid development in the structural study of HSP90 and some surprising new discoveries from genetic studies of gp96. In this review, we focus on the aspect of gp96 as an ER molecular chaperone in protein maturation, peptide binding and the regulation of its activity.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.582-586
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• 2006

This experiment was conducted to investigate the dietary effect of garlic powder (GP) and copper (Cu) on laying performances and the cholesterol content and quality characteristics of eggs during storage in laying hens. A total of one hundred and eighty, 50-wk-old, Hy-Line Brown layers were divided into 6 groups with 3 replicates per group (10 layers per replicate) and fed one of six diets containing GP 0%, GP 1%, GP 3%, GP 5%, Cu 200 ppm, or GP 3%-Cu 200 ppm for 5 wks. There were no differences in the laying performances and feed intakes bertween treatments. Eggshell strength, eggshell thickness and yolk color were also not affected by feeding of GP and Cu. With increasing dietary GP, Haugh unit was linearly increased after 2 wk of storage (p<0.05). The levels of serum total cholesterol in hens fed diets containing GP or Cu were lower than that of the control (p<0.05), but high density lipoprotein-cholesterol was not influenced by dietary GP or Cu. The content of egg yolk cholesterol from hens fed diets containing GP or Cu was significantly decreased from that of the control, except for the GP 1% group. Based on the results of this experiment, the decrease of Haugh unit during storage was alleviated by feeding of GP. The feeding of GP or Cu alone and in combination altered the cholesterol fractions in serum and reduced the content of egg yolk cholesterol in laying hens.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.33-33
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• 1996

An ectodomain of gp41, the transmembrane fusion protein of HIV, without the fusion peptide region was expressed using pET system in E. coli. The expressed protein gp41core, was isolated as inclusion body and was purified by ion-exchange chromatography after solubilized in 6M urea. The purified denatured protein was renaturated and the folded domain of gp41core was identified by the presence of the proteolysis resistence domain and a high content of ${\alpha}$-helical secondary structure. (omitted)

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1539-1544
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• 2014

Purpose: Alpha-fetoprotein (AFP), Lens culinaris agglutinin-reactive fraction of AFP (AFP-L3), and Golgi protein 73 (GP73) levels have been widely used as tumor markers for the diagnosis of hepatocellular carcinoma (HCC). The aim of this study was to investigate whether these tumor markers could be used to monitor short-term treatment response and recurrence of HCC in patients undergoing radiofrequency ablation (RFA). Methods: Between July 2012 and July 2013, 53 consecutive patients with newly diagnosed HCC were prospectively enrolled in this study. Among these, 32 patients underwent RFA, after which they were followed up prospectively at the First Hospital of Jilin University in China. Results: AFP, AFP-L3, and GP-73 values pre-RFA were not associated with tumor size, whereas AFP and GP-73 levels tended to be associated with tumor number, the presence of vascular invasion, deterioration of liver function, advanced-stage disease, and a poor performance status. GP-73 levels were dramatically elevated in the patients with hepatitis C-associated HCC. Neither pre-RFA nor 1-month post-RFA tumor marker values were associated with short-term outcome. The short-term recurrence rate of AFP-positive patients measured 1 month post-RFA was obviously higher than that of AFP-negative patients. Conclusions: AFP and GP-73 values were associated with clinical variables representing tumor growth and invasiveness, and the AFP value measured 1 month post-RFA was a strong predictor of short-term recurrence in patients with HCC.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.185-195
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• 2019

The large surface area and the high electrical conductivity of graphene (GP) allow it to act as an "electron wire" between the redox center of biomolecules and an electrode surface. The faster electron transfer kinetics and excellent catalytic activity of GP facilitate the accurate and selective electrochemical detection of biomolecules. This mini-review provides an overview of the recent developments and progress of GP, functionalized or doped GP, and GP-composites based sensors for the selective and interference-free detection of dopamine (DA). The electrochemical principles and future perspective and challenges of DA sensors were also discussed based on GP.

• 생명과학회지
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• 제18권9호
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• pp.1244-1248
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• 2008

본 연구에서는 다양한 천연 추출물의 P-gp 저해능의 고속 탐색을 통하여 새로운 화학감작제 후보물질을 발굴하고자 하였다. P-gp 활성에 대한 천연 추출물의 저해능은 P-gp이 과발현된 L-MDR1 세포주를 이용하여 대표적인 P-gp 기질 약물인 calcein AM의 세포 내 축적 정도를 측정함으로써 평가하였다. 강황 및 울금은 가장 강력한 P-gp 기능 저해를 나타내었고, 이외에도 Mentrasto, 취호초, 봉출, Rakta chandan, 강진향, 소목, 노회 등의 순으로 P-gp 기능 저해능을 보였다. 이들 추출물에서 P-gp 저해능을 보이는 성분을 확인하기 위하여 LC/MS/MS 분석을 수행한 결과, 기존에 P-gp 활성을 저해한다고 잘 알려진 curcumin 이외에, 다양한 플라보노이드 화합물이 질량 스펙트럼 DB 검색을 통하여 확인되었다. In vitro 연구 결과를 통하여 상기의 천연 추출물이 P-gp 활성을 저해하는 성분을 함유하고 있음을 확인하였다. 향후 이들 천연 추출물의 화학감작제 후보물질로의 사용 가능성에 대한 in vivo 연구가 필요할 것이다.

• Biomolecules & Therapeutics
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• 제20권3호
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• pp.293-298
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• 2012

The purpose of this study was to investigate the modification of expression and functionality of the drug transporter P-glycoprotein (P-gp) by tumor necrosis factor-alpha (TNF-${\alpha}$) and interferon-gamma (IFN-${\gamma}$) at the blood-brain barrier (BBB). We used immortalized human brain microvessel endothelial cells (iHBMEC) and primary human brain microvessel endothelial cells (pHBMEC) as in vitro BBB model. To investigate the change of p-gp expression, we carried out real time PCR analysis and Western blotting. To test the change of p-gp activity, we performed rhodamin123 (Rh123) accumulation study in the cells. In results of real time PCR analysis, the P-gp mRNA expression was increased by TNF-${\alpha}$ or IFN-${\gamma}$ treatment for 24 hr in both cell types. However, 48 hr treatment of TNF-${\alpha}$ or IFN-${\gamma}$ did not affect P-gp mRNA expression. In addition, co-treatment of TNF-${\alpha}$ and IFN-${\gamma}$ markedly increased the P-gp mRNA expression in both cells. TNF-${\alpha}$ or IFN-${\gamma}$ did not influence P-gp protein expression whatever the concentration of cytokines or duration of treatment in both cells. However, P-gp expression was increased after treatments of both cytokines together in iHBMEC cells only compared with untreated control. Furthermore, in both cell lines, TNF-${\alpha}$ or IFN-${\gamma}$ induced significant decrease of P-gp activity for 24 hr treatment. And, both cytokines combination treatment also decreased significantly P-gp activity. These results suggest that P-gp expression and function at the BBB is modulated by TNF-${\alpha}$ or/and IFN-${\gamma}$. Therefore, the distribution of P-gp depending drugs in the central nervous system can be modulated by neurological inflammatory diseases.

• Korean Journal of Mathematics
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• 제7권2호
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• pp.215-218
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• 1999

We investigate characterizations of rings whose simple singular right R-modules are GP-injective. It is proved that if R is a semiprime ring whose simple singular right R-modules are GP-injective, then the center $Z(R)$ of R is a von Neumann regular ring. We consider the condition ($^*$): R satisfies $l(a){\subseteq}r(a)$ for any $a{\in}R$. Also it is shown that if R satisfies ($^*$) and every simple singular right R-module is GP-injective, then R is a reduced weakly regular ring.

• Journal of Pharmaceutical Investigation
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• 제40권5호
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• pp.269-275
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• 2010

P-gp plays a critical role in drug disposition and represents a mechanism for the development of multidrug resistance. Flavonoids, a major class of natural compounds widely present in foods and herbal products, have been shown to inhibit P-gp. Therefore, the aim of this study was to identify new candidate chemosensitizers by screening various plant extracts. The ability of natural plant extracts to inhibit P-gp activity was assessed by measuring cellular accumulation of calcein AM, daunorubicin and vincristine in P-gp overexpressing MDCKII-MDR1 cells. Among more than 800 plant extracts, eight were found to inhibit P-gp activity. Curcuma aromatica extract produced greatest inhibition, followed by Curcuma longa and Dalbergia odorifera extracts. Extracts of Aloe ferox, Curcuma zedoariae rhizome, Zanthoxylum planispinum, and Ageratum conyzoides showed moderate inhibitory effects. Curcumin and quercetin exhibited similar inhibition of P-gpmediated efflux of daunorubicin and vincristine, and flavones had a lesser effect. When chemosensitizing effect was evaluated by measuring daunorubicin sensitivity to MDCKII-MDR1 cells in the presence of natural plant extracts, Curcuma aromatica showed the most potent chemosensitizing effect based on daunorubicin cytotoxicity. In conclusion, natural plant extracts such as Curcuma aromatica can potently inhibit P-gp activity and may have potential as a novel chemosensitizers.

• 분석과학
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• 제32권2호
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• pp.65-76
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• 2019

Despite the expansion of sewage treatment facilities to reduce pollutants in the tributaries of the Han River, water pollution accidents such as fish deaths continue to frequently occur. The purpose of this study was to identify the pollutant sources using water quality and stable isotope ratio (${\delta}^{15}N$, ${\delta}^{13}C$, ${\delta}^{15}N-NH_4$, ${\delta}^{15}N-NO_3$) analysis results in the three inflow tributaries (Gulpocheon (GP), Anyangcheon (AY) and Sincheon (SC)) of the Han River. Water quality was analyzed in June and October from 2013 to 2017, and the results showed that the concentrations of nutrients, such as T-N, $NO_3-N$, and T-P, were increased at GP4, AY3, SC3, and SC4, which lie downstream of sewage treatment facilities. The results of ${\delta}^{15}N$ for June 2017 indicated that the source of nitrogen was sewage or livestock excreta at GP4 and SC4, and organic fertilizers at AY3 and SC3. ${\delta}^{15}N-NO_3$ results suggested that the source of nitrogen was related to organic sewage, livestock or manure at GP4, AY3 and SC4. Therefore, GP4 and SC4 were more influenced by effluent from sewage treatment facilities than by their tributaries, AY3 and SC3 were considered to be influenced more by their tributary than effluent from sewage treatment facilities. With the results of this study, the source of contamination (sewage treatment facility effluent) of river inflow downstream of Han River could be confirmed using water quality and stable isotope ratio.