• Title/Summary/Keyword: ER

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Emodin exerts protective effect against palmitic acid-induced endoplasmic reticulum stress in HepG2 cells

  • Thomas, Shalom Sara;Park, Sora;Cha, Youn-Soo;Kim, Kyung-Ah
    • Journal of Nutrition and Health
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    • v.52 no.2
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    • pp.176-184
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    • 2019
  • Purpose: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. Methods: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as $IRE1{\alpha}$, $eIF2{\alpha}$ and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with $750{\mu}M$ palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. Results: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of $p-IRE1{\alpha}$, $p-eIF2{\alpha}$ and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. Conclusion: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.

Effects of sodium dodecyl sulfate surfactant on up-conversion luminescence of Er3+/Yb3+-codoped NaLa(MoO4)2 nanocolloidal phosphor prepared by pulsed laser ablation in water

  • Kang, SukHyun;Jung, Kyung-Hwan;Kim, Kang Min;Kim, Won Rae;Han, HyukSu;Mhin, Sungwook;Son, Yong;Shim, Kwang Bo;Lee, Jung-Il;Ryu, Jeong Ho
    • Journal of Ceramic Processing Research
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    • v.20 no.2
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    • pp.158-163
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    • 2019
  • Er3+/Yb3+-codoped NaLa(MoO4)2 colloidal nanocrystals were synthesized by pulsed laser ablations in de-ionized water and sodium dodecyl sulfate (NaC12H25SO4, SDS) aqueous solution for up-conversion (UC) luminescence bio-labeling applications. The influences of the SDS molecules on the crystallinities, crystal morphologies, crystallite sizes, and UC luminescence properties of the prepared Er3+/Yb3+-codoped NaLa(MoO4)2 colloidal nanocrystals were investigated in detail. Under a 980-nm excitation, the Er3+/Yb3+-codoped nanocolloidal NaLa(MoO4)2 suspension exhibited a weak red emission near 670 nm and strong green UC emissions at 530 and 550 nm, corresponding to the intra 4f transitions of Er3+ (4F9/2, 2H11/2, 4S3/2) → Er3+ (4I15/2). When the SDS solution was used, a smaller average crystallite size, narrower size distribution, and enhanced UC luminescence were observed. These characteristics were attributed to the amphoteric SDS molecules attached to the positively charged Er3+/Yb3+-codoped NaLa(MoO4)2 colloidal nanocrystals, effectively occupying the oxygen defect on their surfaces. The Er3+/Yb3+-codoped nanocrystalline NaLa(MoO4)2 suspension prepared in the SDS solution exhibited a remarkably strong green emission visible to the naked eyes.

Analysis of Characteristics of Thoracic Injury Patients and Nursing Interventions Using Nursing Intervention Classification by Emergency Room Type (응급실 유형에 따른 흉부외상환자의 특성과 간호중재분류체계를 활용한 간호중재 분석)

  • Kim, Kiung;Kim, Yunhee
    • Journal of Korean Biological Nursing Science
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    • v.23 no.4
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    • pp.257-266
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    • 2021
  • Purpose: The purpose of this study was to analyze the content of nursing interventions applied to patients with thoracic injury who visited a trauma emergency room (TER) or an emergency room (ER). Methods: Of 3,938 trauma patients admitted to this hospital between January 1, 2019 and December 31, 2020, 320 adult patients with thoracic injury (94 to TER, 226 to ER) who met the inclusion criteria were enrolled. Patients' data were acquired from their electronic medical records. General and clinical characteristics of these subjects along with nursing interventions were analyzed. Results: There were statistically significant differences in the length of stay, treatment outcome, and level of consciousness between thoracic injury patients who visited TER and ER. Average thoracic Abbreviated Injury Scale score and average Injury Severity Score of thoracic injury patients who visited TER were 3.13 and 13.54, respectively, which were significantly higher than those of patients who visited ER. The numbers of nursing actions applied was 4,819 for TER and 3,944 for ER, which were classified into five domains, 18 classes, and 56 interventions. The most domain of interventions carried out in both TER and ER was physiological: complex. Classes including Crisis management and Thermoregulation were not carried out in ER. On average, 16 more types of interventions were carried out in TER than in ER. Conclusion: This study demonstrated characteristics of thoracic injury patients and nursing interventions by emergency room type. Based on results of this study, standardized nursing interventions need be applied to thoracic injury patients visiting TER and ER.

N-recognins UBR1 and UBR2 as central ER stress sensors in mammals

  • Ly Thi Huong Luu Le;Seoyoung Park;Jung Hoon Lee;Yun Kyung Kim;Min Jae Lee
    • Molecules and Cells
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    • v.47 no.1
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    • pp.100001.1-100001.8
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    • 2024
  • In eukaryotes, a primary protein quality control (PQC) process involves the destruction of conformationally misfolded proteins through the ubiquitin-proteasome system. Because approximately one-third of eukaryotic proteomes fold and assemble within the endoplasmic reticulum (ER) before being sent to their destinations, the ER plays a crucial role in PQC. The specific functions and biochemical roles of several E3 ubiquitin ligases involved in ER-associated degradation in mammals, on the other hand, are mainly unknown. We identified 2 E3 ligases, ubiquitin protein ligase E3 component N-recognin 1 (UBR1) and ubiquitin protein ligase E3 component N-recognin 2 (UBR2), which are the key N-recognins in the N-degron pathway and participate in the ER stress response in mammalian cells by modulating their stability. Cells lacking UBR1 and UBR2 are hypersensitive to ER stress-induced apoptosis. Under normal circumstances, these proteins are polyubiquitinated through Lys48-specific linkages and are then degraded by the 26S proteasome. In contrast, when cells are subjected to ER stress, UBR1 and UBR2 exhibit greater stability, potentially as a cellular adaptive response to stressful conditions. Although the precise mechanisms underlying these findings require further investigation, our findings show that cytoplasmic UBR1 and UBR2 have anti-ER stress activities and contribute to global PQC in mammals. These data also reveal an additional level of complexity within the mammalian ER-associated degradation system, implicating potential involvement of the N-degron pathway.

Preoperative neutrophil-to-lymphocyte ratio is prognostic for early recurrence after curative intrahepatic cholangiocarcinoma resection

  • Woo Jin Choi;Fiorella Murillo Perez;Annabel Gravely;Tommy Ivanics;Marco P. A. W. Claasen;Liza Abraham;Phillipe Abreu;Robin Visser;Steven Gallinger;Bettina E. Hansen;Gonzalo Sapisochin
    • Annals of Hepato-Biliary-Pancreatic Surgery
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    • v.27 no.2
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    • pp.158-165
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    • 2023
  • Backgrounds/Aims: Within two years of surgery, 70% of resected intrahepatic cholangiocarcinoma (iCCA) recur. Better biomarkers are needed to identify those at risk of "early recurrence" (ER). In this study, we defined ER and investigated whether preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic-inflammatory index were prognostic of both overall relapse and ER after curative hepatectomy for iCCA. Methods: A retrospective cohort of patients who underwent curative-intent hepatectomy for iCCA between 2005 and 2017 were created. The cut-off timepoint for the ER of iCCA was estimated using a piecewise linear regression model. Univariable analyses of recurrence were conducted for the overall, early, and late recurrence periods. For the early and late recurrence periods, multivariable Cox regression with time-varying regression coefficient analysis was used. Results: A total of 113 patients were included in this study. ER was defined as recurrence within 12 months of a curative resection. Among the included patients, 38.1% experienced ER. In the univariable model, a higher preoperative NLR (> 4.3) was significantly associated with an increased risk of recurrence overall and in the first 12 months after curative surgery. In the multivariable model, a higher NLR was associated with a higher recurrence rate overall and in the ER period (≤ 12 months), but not in the late recurrence period. Conclusions: Preoperative NLR was prognostic of both overall recurrence and ER after curative iCCA resection. NLR is easily obtained before and after surgery and should be integrated into ER prediction tools to guide preoperative treatments and intensify postoperative follow-up.

Performance Evaluation of a Mixed-Mode Type ER Engine Mount (I);Manufacturing and Test of Engine Mount (복합모드형 ER엔진마운트의 성능평가 (I);엔진마운트의 제작 및 시험)

  • Choe, Yeong-Tae;Choe, Seung-Bok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.2 s.173
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    • pp.370-377
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    • 2000
  • This paper presents a mixed-mode type ER(electro-rheological) engine mount, and its vibration control performance for a passenger vehicle is presented. The field-dependent yield stress of a transfo rmer oil-based ER fluid is empirically distilled in both shear and flow modes. This is then incorporated with the governing equation of motion of the proposed mixed-mode(shear mode plus flow mode) type engine mount. The damping force is analyzed with respect to the intensity of the electric field and design parameters such as electrode gap. Subsequently, the ER engine mount which is equivalent to the conventional hydraulic engine mount in terms of the damping level is designed and manufactured. Both computer simulation and experimental test are undertaken in order to evaluate vibration isolation performance. In addition, this performance is compared with that of the conventional hydraulic engine mount.

A Modeling Study of Local Equivalence Ratio Fluctuation in Imperfectly Premixed Turbulent Flames

  • Moon, Hee-Jang
    • Journal of Mechanical Science and Technology
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    • v.18 no.8
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    • pp.1479-1489
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    • 2004
  • The effect of fluctuation of Equivalence Ratio (ER) in a turbulent reactive field has been studied in order to check the global combustion characteristics induced by the local fluctuation. When the flow is premixed on a large scale, closer examination on a small scale reveals that local fluctuations of ER exist in an imperfectly premixed mixture, and that these fluctuations must be considered to correctly estimate the mean reaction rate. The fluctuation effect is analyzed with DNS by considering the joint PDF of reactive scalar and ER, followed by modeling study where an extension of stochastic mixing models accounting for the ER fluctuation is reviewed and tested. It was found that models prediction capability as well as its potential is in favor to this case accounting the local ER fluctuation. However, the effect of local fluctuation did not show any notable changes on the mean global characteristics of combustion when statistical independence between the reactive scalar and ER field is imposed, though it greatly influenced the joint PDF distribution. The importance of taking into account the statistical dependency between ER and combustible at the initial phase is demonstrated by testing the modeled reaction rate.

Comparison of Phenol Removal between Electrochemical Reaction and Plasma Reaction

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
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    • v.25 no.7
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    • pp.905-916
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    • 2016
  • The characteristics of phenol removal and $UV_{254}$ matters variance were investigated and compared by the variation of operating factors (NaCl concentration, air flow rate, initial phenol concentration) in electrochemical reaction (ER) and dielectric barrier discharge plasma reaction (DBDPR), respectively. The phenol removal rate was shown as $1^{st}$ order both in ER and DBDPR. Also, the absorbance of $UV_{254}$ matters which means aromatic intermediates was analyzed to investigate the complete phenol degradation process. In ER, the phenol degradation and aromatic intermediates production rates increased by the increase of NaCl concentration. However, in DBDPR, the variation of NaCl concentration had no effect on the degradation of phenol and $UV_{254}$ matters. Air flow rate had a little effect on the removal of phenol and the variation of $UV_{254}$ matters in ER. The phenol removal rate in ER was a little higher than that in DBDPR. The produced $H_2O_2$ and $O_3$ amounts in ER were 2 times and 10 times higher than those in DBDPR. The chlorine intermediates ($ClO_2$ and free chlorine) were produced in ER, however, they were not produced in DBDPR.

Hypothermia Regulates Endoplasmic Reticulum (ER) Stress through the X-box Binding Protein-1 (XBP1) Gene Expression in PC12 Cells

  • Yoo, Bo-Kyung;Kwon, Kisang;Lee, Eun Ryeong;Kwon, O-Yu
    • Biomedical Science Letters
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    • v.23 no.4
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    • pp.416-420
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    • 2017
  • Endoplasmic reticulum (ER) stress induces unfolded protein response (UPR) via inositol-requiring enzyme 1 (IRE1) activation, which sends a molecular signal for X box-binding protein 1 (XBP1) mRNA splicing in the cytosol. IRE1 endoribonuclease activity induces cleavage of XBP1 mRNA. The XBP1 mRNA is then ligated by an uncharacterized RNA ligase and translated to produce spliced XBP1 by 23 nt removed in which contains the PstI restriction enzyme site. The splicing of XBP1 mRNA can be detected by semiquantitative RT-PCR, and then splicing of XBP1 is a useful tool to measure the genetic variability in ER stress. In this study, we have estimated IRE1-dependent splicing of XBP1 mRNA under conditions of various hypothermia. The results indicated that hypothermia regulated ER stress. This study demonstrated that hypothermia is closely related to ER stress and may be useful for early diagnosis of ER-associated disease.

Role of Osmotic and Salt Stress in the Expression of Erythrose Reductase in Candida magnoliae

  • Park, Eun-Hee;Lee, Ha-Yeon;Ryu, Yeon-Woo;Seo, Jin-Ho;Kim, Myoung-Dong
    • Journal of Microbiology and Biotechnology
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    • v.21 no.10
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    • pp.1064-1068
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    • 2011
  • The osmotolerant yeast, Candida magnoliae, which was isolated from honeycomb, produces erythritol from sugars such as fructose, glucose, and sucrose. Erythrose reductase in C. magnoliae (CmER) reduces erythrose to erythritol with concomitant oxidation of NAD(P)H. Sequence analysis of the 5'-flanking region of the CmER gene indicated that one putative stress response element (STRE, 5'-AGGGG-3'), found in Saccharomyces cerevisiae, exists 72 nucleotides upstream of the translation initiation codon. An enzyme activity assay and semiquantitative reverse transcription polymerase chain reaction revealed that the expression of CmER is upregulated under osmotic and salt stress conditions caused by a high concentration of sugar, KCl, and NaCl. However, CmER was not affected by osmotic and oxidative stress induced by sorbitol and $H_2O_2$, respectively. The basal transcript level of CmER in the presence of sucrose was higher than that in cells treated with fructose and glucose, indicating that the response of CmER to sugar stress is different from that of GRE3 in S. cerevisiae, which expresses aldose reductase in a sugarindependent manner. It was concluded that regulation of CmER differs from that of other aldose reductases in S. cerevisiae.