• Journal of the Korean institute of surface engineering
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• v.27 no.1
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• pp.12-18
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• 1994

The plasma spray process was used to deposit coatings of $ZrO_2$-8wt%Y2O3 powders on mild steel sub-strate, and the characteristics of as-deposited and heat treated coatings have been investigated. Particulary, the variations of porosity, wear resistance, thermal barrier and thermal shock resistance in $ZrO_2$-8wt% $Y_2O_3$coatings after heat treatment under vacuum circumstance have been investigated. The porosity of the coating layer was increased with increased spray distance. In the case of the arc current of 450A and at the spray distance of 50mm, it was obtained the lowest amount of porosity. After heat treatment, the amount of porosity was found to be decreased, and the wear resistance, microhardness and thermal shock resistance were im-proved. However, the thermal barrier was decreased.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.651-657
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• 2003

In order to examine if arsenic, one of environmental stresses, contributes to hypertension as one of cardiovas cular pathological factors, this study was perfarmed in vivo and in vitro, using intacted or pithed rats and aorta ring preparation, respectively. And also the relationship between expression of heat shock protein (HSP) 90 and vasoactives-induced contractile response was elucidated. To measure blood pressure, the carotid arterial pressure was recorded on physiograph(Grass Co. 79E) connected to strain gauge. On the other hand, contractile response of vascular ring preparation isolated from rat was determined in organ bath and was recorded on physiograph connected to isometric transducer. And HSP was detacted by Western blotting whole cell Iysis. Preganglionic nerve stimulation was increased by 26.0% in arterial pressure of rat treated with arsenic. Vascular contractile response was monitored and HSP were measured by Western blotting of whole Iysis prepared from samples exposed with 0, 0.5, 1, 2 and 4 mM of arsenic for 8 hours. The dose-vascular responses of potassium chloride were augmented by increasing dose of arsenic in the strips exposed to arsenic for 8 hours, and were not augmented for 1, 3, 5 hours. And the response of relaxation of rat aorta induced by histamine was not influenced by arsenic stress. The increase of HSP 90 expression in rat aorta was pronounced at 8 hours after 4 mM of arsenic treatment, but HSP 60 expression was not. Arsenic stress not only increased the expression of HSP 90 in the rat aorta, but also augmented contractions to potassium chloride. These results indicated that arsenic stress was sufficient to induce heat shock protein 90, resulting in increased vascular contractility in rat aorta.

• BMB Reports
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• v.33 no.5
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• pp.407-411
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• 2000

The effects of heat shock, or all-trans retinoic acid, on the expression of the C-reactive protein mRNA in the HT-29 human colon carcinoma cells, as well as the functional role of the C-reactive protein as a molecular chaperone, were studied. The expression level of the C-reactive protein mRNA in the HT-29 cells was increased time-dependently when exposed to heat-shock, and dose-dependently when treated with all-trans retinoic acid. The activities of transglutaminase C and K in the HT-29 cells were significantly increased when treated with all-trans retinoic acid. The C-reactive protein prevented thermal aggregation of the citrate synthase and stabilized the target enzyme, citrate synthase. The C-reactive protein promoted functional refolding of the urea-denatured citrate synthase up to 40-70%. These results suggest that the C-reactive protein, which is induced in human colon carcinoma cells, when heated or treated with all-trans retinoic acid has in a part functional activity of the molecular chaperone.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.4
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• pp.303-310
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• 1998

We studied expression patterns of thermotolerance gene (BcHSP17.6) in cabbages which was isolated from Chinese cabbage and we will attempt transformation of forage crops with the gene in order to increase thermotolerance of forage crops. Antiserum against a BcHSP17.6 protein was reacted with its antigen. With this antiserum, the accumulation of the 15- to 18-kD LMW HSPs under various heat shock (HS) conditions was quantified. The LMW HSPs began to be detectable at $35^{\circ}C$, and after 4 hours at $40^{\circ}C$ they were accumulated to a maximum level of 1.56 micrograms per 100 micrograms of total proteins in cabbage leaves and remained almost unchanged up to 24 hours after HS. Accumulation of the HSPs was reduced at temperatures higher than $40^{\circ}C$. We conclude that accumulation of these LMW HSPs are necessary for Chinese cabbages to survive at an otherwise lethal temperature.

• Journal of Korean Society on Water Environment
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• v.29 no.2
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• pp.232-238
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• 2013

Water temperature is key factor influencing growth and reproduction of fish and its increase give rise to various physiological changes including gene expression. Heat shock protein (Hsp), one of the molecular chaperones, is highly conserved throughout evolution and its expression is induced by various stressors such as temperature, oxidative, physical and chemical stresses. Here, we isolated partial cDNA clones encoding 70-kDa Hsp (Hsp70) and $\beta$-actin using reverse transcriptase-PCR (RT-PCR) from gut of Rhynchocypris kumgangensis, a Korean indigenous species and cold-water fish, and investigated expression profiles of Hsp70 under an increase of water temperature using $\beta$-actin as an internal control for RT-PCR. Cloned Hsp70 cDNA of R. kumgangensis showed homology to Ctenopharyngodon idella (96%), Hypophthalmichthys molitrix (96%), Danio rerio (93%) and Oncorhynchus mykiss (81%) Hsp70. Cloned $\beta$-actin cDNA of R. kumgangensis showed homology to D. rerio (98%), H. molitrix (97%), C. idella (97%) and O. mykiss (90%) $\beta$-actin. Both mRNA of Hsp70 and $\beta$-actin were expressed in gut, brain, and liver in R. kumgangensis. Futhermore, expression of Hsp70, in brain, was highly augmented by an increase of water temperature. These results suggest that Hsp70 mRNA expression level in brain can be used as a biological molecular marker to represent physiological stress against an increase of water temperature.

• Molecules and Cells
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• v.19 no.3
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• pp.328-333
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• 2005

Small heat shock proteins (sHSPs) are widely distributed, and their function and diversity of structure have been much studied in the field of molecular chaperones. In plants, which frequently have to cope with hostile environments, sHSPs are much more abundant and diverse than in other forms of life. In response to high temperature stress, sHSPs of more than twenty kinds can make up more than 1% of soluble plant proteins. We isolated a genomic clone, NtHSP18.3, from Nicotiana tabacum that encodes the complete open reading frame of a cytosolic class I small heat shock protein. To investigate the function of NtHSP18.3 in vitro, it was overproduced in Escherichia coli and purified. The purified NtHSP18.3 had typical molecular chaperone activity as it protected citrate synthase and luciferase from high temperature-induced aggregation. When E. coli celluar proteins were incubated with NtHSP18.3, a large proportion of the proteins remained soluble at temperatures as high as $70^{\circ}C$. Native gel analysis suggested that NtHSP18.3 is a dodecameric oligomer as the form present and showing molecular chaperone activity at the condition tested. Binding of bis-ANS to the oligomers of NtHSP18.3 indicated that exposure of their hydrophobic surfaces increased as the temperature was raised. Taken together, our data suggested that NtHSP18.3 is a molecular chaperone that functions as a dodecameric complex and possibly in a temperature-induced manner.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.157-164
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• 1988

SCK tumor cells were exposed to heat shock or several sulihydryl-reacting agents such as iodoacetamide(IAA), zinc chloride(Zn), and 2-mercaptoethanol(ME). Stress proteins induced by these agents were examined and the relationship between the induction of stress proteins and the production of abnormal proteins was discussed. Based on the present experiments, two classes of intracellular pathways for the induction of stress proteins were defined; one dependent on and the other independent of protein synthesis. The presence of cycloheximide during the induction period blocked the formation of stress proteins in the cells exposed to Zn or ME, but not in those exposed to heat shock or IAA.Therefore, stress protein seems to be induced either by denaturation of pre-existing mature proteins (e.g., heat shock or IAA) or by newly synthesized abnormal proteins(e.g., Zn or ME). In conclusion, it is ilkely that the production of abnormal proteins by stresses triggers stress protein induction. In addition, it was found that the cells exposed to IISP and GRP inducers simultaneously responded to more strong stress among several stresses encountered.

• The Korean Journal of Zoology
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• v.38 no.4
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• pp.557-564
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• 1995

The 90 kDa-heat shock protein (HSP90) is one of the major ubiquitous heat shock proteins induced by a vadety of ceilular stresses. HSP90 Is constitutively synthesized even under nonstressed condidons and found In association with several regulatory and structural proteins such as protein kinases and steroid hormone receptors. In the present study, to facilitate its biochemical characterization, HSP90 was pudfied from chick muscle by sequential column chromatography steps including DEAE- cellulose, hydroxyapatite, and Sephacryl S-300 gel filtration and monoclonal antillodies specific to HSP90 were produced by the inurine hybridomal technique. We report the production of 4 posItive hybridoma clones, named as A204, C112, C302 and A204, C112, C302. Among these MoAbs, Cl 12 strongly reconnized chick HSP90 in Western blot and native immunoprocipitation. In addition, C112 showed the crossreactivitles against HSP90 from human, rabbit, mouse, fish and chick but not from Drosophila and E. coil.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.25-30
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• 2010

This study was carried out to understand the effect of low temperature($4^{\circ}C$), heat shock($37^{\circ}C$) and drought stresses on the growth and gene expression of Arabidopsis ATSIZ3(at1g08910) mutants. The seedling growth of SIZ3-mutants were markedly inhibited by the treatment of heat shock or chilling stresses. However, there was no significant differences between wild type and SIZ3-mutants in seeding fresh weight. As compared to wild type plants, SIZ3-mutants showed 63.9% inhibition of seedling fresh weight by the treatment of 10 days drought stress, suggesting that SIZ3 is involved in the resistance of Arabidopsis to drought stress. Base on RT-PCR analysis, expression of SIZ3 mRNA in the wild type showed 20% inhibition by chilling stress, 3.7 and 4.5 fold increase by the treatment of heat shock or drought stresses, respectively.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.317-322
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• 2010

Purpose: There is no clear evidence of the original cause of hypertrophic scar, and the effective method of treatment is not yet established. Recently the steps of searching in gene and molecular level are proceeding. we are trying to recognize the difference between keratinocytes of hypertrophic scar and normal skin. Then we do support the comprehension of the scar formation mechanism and scar management. Methods: Total RNAs were extracted from cultured keratinocytes from 4 hypertrophic scars and normal skins. The cDNA chips were prepared. A total of 3063 cDNAs from human cDNA library were arrayed. And the scanning data were analyzed. Results: On microarray, heat shock protein, pyruvate kinase, tumor rejection antigen were more than 2 fold intensity genes. Among them, heat shock 70 kd protein showed the strongest intensity difference. Conclusion: In this study, it can be concluded that heat shock proteins play an important role in the process of wound healing and scar formation. This study provides basic biologic information for scar research. The new way of the prevention and treatment of scar formation would be introduced with further investigations.