• Title/Summary/Keyword: Oxidation stress

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The Technology of Sloped Wall SWAMI for VLSI and Analysis of Leakage Current (고집적 회로를 위한 경사면 SWAMI 기술과 누설전류 분석)

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    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.3
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    • pp.252-259
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    • 1990
  • This paper present new scheme for a Side Wall Masked Isolation(SWAMI) technology which take all the advatages provided by conventional LOCOS process. A new SWAMI process incorporates a sloped sidewall by reactive ion etch and a layer of thin nitride around the side walls such that both intrinsic nitride stress and volume expansion induced stress are greatly reduced. As a fabricate results, a defect-free fully recessed zero bird's beak local oxidation process can be realized by the sloped wall anisotropic oxide isolation. No additional masking step is required. The leakage current of PN diodes of this process were reduced than PN diode of conventional LOCOS process. On the other hand, the edge junction part was larger than the flat juction part in the density of leakage current.

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A Study on the Mechanical Change of Emulsion-Treated Hair by Color

  • Ko, Hee-Ja;Park, Jang-Soon
    • Textile Coloration and Finishing
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    • v.34 no.2
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    • pp.127-133
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    • 2022
  • With the increasing interest in the expression of individuality and appearance of modern people, it is time to conduct research and development of novel hair coloring from various angles. Therefore, taking into account the order of discoloration of hair pigments, we selected a creative and novel emulsion as a novel material for hair coloring, rather than a cosmetic material such as hot water extract using natural products dealt with in previous studies, commercially available hair manicure, and oxidation hair dye for hair. Thus, the change in tensile strength and elongation of hair samples by color was studied. As a result of the study, hair with green emulsion paint had a significantly higher maximum load, maximum stress, maximum elongation and breaking load, breaking stress, breaking elongation values are shown. Maximum in terms of modulus, green emulsion applied hair and the control group were higher in the 0-15s strain and 15-145s sections, respectively, and the tangential modulus value was much higher in the control group than the experimental group hairs in all the 0-145s sections. This study, which analyzes the dynamic changes of hair samples that extend the daily color gamut, will greatly contribute to the development of innovative hair coloring materials in the research and production of hair beauty works, and it is judged that it will also contribute to the development of the beauty industry.

Electrical Characterization of Ultrathin $SiO_2$ Films Grown by Thermal Oxidation in $N_2O$ Ambient ($N_2O$ 분위기에서 열산화법으로 성장시킨 $SiO_2$초박막의 전기적 특성)

  • Gang, Seok-Bong;Kim, Seon-U;Byeon, Jeong-Su;Kim, Hyeong-Jun
    • Korean Journal of Materials Research
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    • v.4 no.1
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    • pp.63-74
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    • 1994
  • The ultrathin oxide films less than 100$\AA$ were grown by thermal oxidation in $N_2O$ ambient to improve the controllability of thickness, thickness uniformity, process reproducibility and their electrical properties. Oxidation rate was reduced significantly at very thin region due to the formation of oxynitride layer in $N_2O$ ambient and moreover nitridation of the oxide layer was simultaneously accompanied during growth. The nitrogen incorporation in the grown oxide layer was characterized with the wet chemical etch-rate and ESCA analysis of the grown oxide layer. All the oxides thin films grown in $N_2O$, pure and dilute $O_2$ ambients show Fowler-Nordheim electrical conduction. The electrical characteristics of thin oxide films grown in $N_2O$ such as leakage current, electrical breakdown, interface trap density generation due to the injected electron and reliability were better than those in pure or dilute ambient. These improved properties can be explained by the fact that the weak Si-0 bond is reduced by stress relaxation during oxidation and replacement by strong Si-N bond, and thus the trap sites are reduced.

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Anti-inflammatory and anti-oxidative effects of 3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride on β-amyloid-induced microglial activation

  • Yang, Seung-Ju;Kim, Jiae;Lee, Sang Eun;Ahn, Jee-Yin;Choi, Soo Young;Cho, Sung-Woo
    • BMB Reports
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    • v.50 no.12
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    • pp.634-639
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    • 2017
  • We aimed to assess the anti-inflammatory and antioxidative properties of KHG26792, a novel azetidine derivative, in amyloid ${\beta}$ ($A{\beta}$)-treated primary microglial cells. KHG26792 attenuated the $A{\beta}-induced$ production of inflammatory mediators such as IL-6, $IL-1{\beta}$, $TNF-{\alpha}$, and nitric oxide. The levels of protein oxidation, lipid peroxidation, ROS, and NADHP oxidase enhanced by $A{\beta}$ were also downregulated by KHG26792 treatment. The effects of KHG26792 against the $A{\beta}-induced$ increases in inflammatory cytokine levels and oxidative stress were achieved by increasing the phosphorylation of $Akt/GSK-3{\beta}$ signaling and by decreasing the $A{\beta}-induced$ translocation of $NF-{\kappa}B$. Our results provide novel insights into the use of KHG26792 as a potential agent against $A{\beta}$ toxicity, including its role in the reduction of inflammation and oxidative stress. Nevertheless, further investigations of cellular signaling are required to clarify the in vivo effects of KHG26792 against $A{\beta}-induced$ toxicity.

Antioxidative Effect of Fermented Rhynchosia nulubilis in Obese Rats (비만 흰쥐에서 발효 서목태의 항산화 효과)

  • Bae, Gui-jeong;Ha, Bae-jin
    • Journal of Food Hygiene and Safety
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    • v.30 no.4
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    • pp.383-389
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    • 2015
  • This study was to examine the antioxidative activity of fermented Rhynchosia nulubilis (FRN) in obese rats. Oxidative stress due to reactive oxygen species (ROS) can cause oxidative damage to cells. Mitochondria are especially important in the oxidative stress as ROS have been found to be constantly generated as an endogen threat. Mitochondrial defense depends mainly on superoxide dismutase whereas microsomal defense depends on catalase, which is an enzyme abundant in microsomes. Seven weeks-aged female Sprague-Dawley rats were divided into four groups and fed high fat diets for 44 days. Also fermented Rhynchosia nulubilis was administered orally for 44 days at 7.5 ml/kg of body weight of rats. The antioxidative activities of fermented Rhynchosia nulubilis were measured by the superoxide dismutase, catalase, malondialdehyde levels in liver homogenate. The levels of malondialdehyde in FRN-treated groups were lower than those in obese groups. Superoxide dismutase and catalase levels were significantly increased. These results demonstrated that fermented Rhynchosia nulubilis had the inhibitive effects of oxidative stress in obese rats, suggesting that fermented Rhynchosia nulubilis would be used as an ingredient of the useful functional products.

Endogenous catalase delays high-fat diet-induced liver injury in mice

  • Piao, Lingjuan;Choi, Jiyeon;Kwon, Guideock;Ha, Hunjoo
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.3
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    • pp.317-325
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    • 2017
  • Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease in parallel with worldwide epidemic of obesity. Reactive oxygen species (ROS) contributes to the development and progression of NAFLD. Peroxisomes play an important role in fatty acid oxidation and ROS homeostasis, and catalase is an antioxidant exclusively expressed in peroxisome. The present study examined the role of endogenous catalase in early stage of NAFLD. 8-week-old male catalase knock-out (CKO) and age-matched C57BL/6J wild type (WT) mice were fed either a normal diet (ND: 18% of total calories from fat) or a high fat diet (HFD: 60% of total calories from fat) for 2 weeks. CKO mice gained body weight faster than WT mice at early period of HFD feeding. Plasma triglyceride and ALT, fasting plasma insulin, as well as liver lipid accumulation, inflammation (F4/80 staining), and oxidative stress (8-oxo-dG staining and nitrotyrosine level) were significantly increased in CKO but not in WT mice at 2 weeks of HFD feeding. While phosphorylation of Akt (Ser473) and $PGC1{\alpha}$ mRNA expression were decreased in both CKO and WT mice at HFD feeding, $GSK3{\beta}$ phosphorylation and Cox4-il mRNA expression in the liver were decreased only in CKO-HF mice. Taken together, the present data demonstrated that endogenous catalase exerted beneficial effects in protecting liver injury including lipid accumulation and inflammation through maintaining liver redox balance from the early stage of HFD-induced metabolic stress.

A new biomarker for the early diagnosis of ovarian torsion: SCUBE-1

  • Uyanikoglu, Hacer;Hilali, Nese Gul;Yardimciel, Mesut;Koyuncu, Ismail
    • Clinical and Experimental Reproductive Medicine
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    • v.45 no.2
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    • pp.94-99
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    • 2018
  • Objective: Prompt diagnosis and management are essential for saving the adnexal organs from infarction in cases of ovarian torsion (OT). This study aimed to determine the diagnostic significance of signal peptide, complement C1r/C1s, Uegf, and Bmp1 (CUB), and epidermal growth factor-like domain-containing protein-1 (SCUBE-1) levels in cases of OT, an emergent ischemic condition, and the relationship of SCUBE-1 with oxidative stress parameters. Methods: This prospective study was conducted among 15 OT patients and 20 age- and gravidity-matched healthy women. SCUBE-1 serum concentrations were determined by using enzyme-linked immunosorbent assays. In addition, oxidative stress was evaluated by measuring the serum levels of advanced oxidation protein products (AOPP), ferric reducing ability of plasma (FRAP), and glutathione (GSH). Results: The SCUBE-1 titers were significantly higher in the patients with OT than in the controls (p=0.008). In addition, serum FRAP and GSH levels were significantly lower in the OT patients than in the controls (p<0.001 for both). Serum AOPP levels were higher in the OT patients, but this trend was not statistically significant (p>0.05). Furthermore, there were no correlations between SCUBE-1 levels and age, gravidity, parity, cyst size, and AOPP, FRAP, or GSH levels (p>0.05). Conclusion: We believe that SCUBE-1 may be a promising biomarker for the early diagnosis of OT.

Biological functions of histidine-dipeptides and metabolic syndrome

  • Song, Byeng Chun;Joo, Nam-Seok;Aldini, Giancarlo;Yeum, Kyung-Jin
    • Nutrition Research and Practice
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    • v.8 no.1
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    • pp.3-10
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    • 2014
  • The rapid increase in the prevalence of metabolic syndrome, which is associated with a state of elevated systemic oxidative stress and inflammation, is expected to cause future increases in the prevalence of diabetes and cardiovascular diseases. Oxidation of polyunsaturated fatty acids and sugars produces reactive carbonyl species, which, due to their electrophilic nature, react with the nucleophilic sites of certain amino acids. This leads to formation of protein adducts such as advanced glycoxidation/lipoxidation end products (AGEs/ALEs), resulting in cellular dysfunction. Therefore, an effective reactive carbonyl species and AGEs/ALEs sequestering agent may be able to prevent such cellular dysfunction. There is accumulating evidence that histidine containing dipeptides such as carnosine (${\beta}$-alanyl-L-histidine) and anserine (${\beta}$-alanyl-methyl-L-histidine) detoxify cytotoxic reactive carbonyls by forming unreactive adducts and are able to reverse glycated protein. In this review, 1) reaction mechanism of oxidative stress and certain chronic diseases, 2) interrelation between oxidative stress and inflammation, 3) effective reactive carbonyl species and AGEs/ALEs sequestering actions of histidine-dipeptides and their metabolism, 4) effects of carnosinase encoding gene on the effectiveness of histidine-dipeptides, and 5) protective effects of histidine-dipeptides against progression of metabolic syndrome are discussed. Overall, this review highlights the potential beneficial effects of histidine-dipeptides against metabolic syndrome. Randomized controlled human studies may provide essential information regarding whether histidine-dipeptides attenuate metabolic syndrome in humans.

Immunological Study of Induction to Salivary Glands the Cytochrome P450(IIE1) by Stress in Rat (백서 타액선의 스트레스 유도 Cytochrome P450 IIE1(CYPIIE1)에 관한 면역학적 연구)

  • Jin-Pyo Lee;Jung-Pyo Hong
    • Journal of Oral Medicine and Pain
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    • v.21 no.2
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    • pp.331-349
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    • 1996
  • Cytochrome P45O is an oxidase involved in oxidation of alcohol and is known to be an activator of carcinogen. The present study was performed to study the effect of alcohol and cold stress on the expression of Cytochrome P450 IIEl (CYPIIE1) In the liver and salivary glands in rats by an immunoblot analysis. Sixteen rats were divided into 4 groups; 1)rats belonging to group I were allowed to take 15%(v/v) ethyl alcohol as a drink ad libitum: 2)rats of group II were bathed in cold water for 30 sec twice a day (during the one-week experiment); 3)rats comprising group III were received alcohol and cold stress as described above; 4)rats of group IV were selected as a control. The rat were sacrificed at the end of the one-week experiment. The livers and parotid and submandibular salivary glands were removed and stored at -2$0^{\circ}C$ until use. The stored organs were homogenized for 10 sec and the supernatants were obtained by centrifugation. The proteins of the supernatants were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and subjected to Western blotting. The blotted membranes were incubated with polyclonal antibodies to CYPIIEI . The obtained results were as follows : 1. The expression of CYPIIEl was apparently negative in the liver and salivary glands of group IV, wheras its expression was marked in the experiment groups I, II. and III. 2. No difference in the expression of CYPIIEl in the liver and salivary glands was observed between the experiment groups I, II, and III. 3. Among the experiment groups, the expression of CYPIIE1 in the liver was much greater than in the salivary glands. The expression of CYPIIE1 in the submandibular gland was weakly positive but was greater than in the carotid gland.

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Effect of Cigarette Smoke Exposure Against Oxidative Damage in Scrapie-infected Mice

  • Sohn, Hyung-Ok;Moon, Ja-Young;Lim, Heung-Bin;Lee, Dong-Wook
    • Journal of the Korean Society of Tobacco Science
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    • v.31 no.1
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    • pp.29-38
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    • 2009
  • Although prion diseases, a group of fatal neurodegenerative diseases of human and animals, are presumed to be caused by several mechanisms including abnormal change of prion protein, oxidative stress is still believed to play a central role in development of the diseases. Cigarette smoking has a few beneficial effects on neuronal diseases such as Alzheimer's disease and Parkinson's disease despite of many detrimental effects. In this study, we investigated how chronic cigarette smoking could exert such beneficial effect against oxidative damage. For this study, homogenates of 87V scrapie-infected brain was inoculated on intracerebral system of IM mice through stereotaxic microinjection and biochemical properties concerning with oxidative stress were examined. The scrapie infection decreased the activity of mitochondrial Mn-containing superoxide dismutase by 50% of the control, meanwhile the effects on other antioxidant enzymes including Cu or Zn-containing superoxide dismutase were not significant. Additionally, the infection elevated superoxide level as well as monoamine oxide-B (MAO-B) in the infected brain. Interestingly, many of the detrimental effects were improved in partial or significantly by long-term cigarette smoke exposure (CSE). CSE not only completely prevented the generation of mitochondrial superoxide but also significantly (p<0.05) decreased the elevated mitochondrial MAO-B activity in the infected brain. Concomitantly, CSE prevented subsequent protein oxidation and lipid peroxidation caused by scrapie infection; however, it did not affect the activities of antioxidant enzymes. These results suggest that chronic exposure of cigarette smoke contribute to in part preventing the progress of neurodegeneration caused by scrapie infection.