• Title/Summary/Keyword: differential mechanism

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Nitric Oxide Synthase Inhibitor Decreases NMDA-Induced Elevations of Extracellular Glutamate and Intracellular $Ca^{2+}$ Levels Via a cGMP-Independent Mechanism in Cerebellar Granule Neurons

  • Oh, Sei-Kwan;Yun, Bong-Sik;Ryoo, In-Ja;Patrick P.McCaslin;Yoo, Ick-Dong
    • Archives of Pharmacal Research
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    • v.22 no.1
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    • pp.48-54
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    • 1999
  • These studies were designed to examine the differential effect of nitric oxide (NO) and cGMP on glutamate neurotransmission. In primary cultures of rat cerebellar granule cells, the glutamate receptor agonist N-methyl-D-aspartate (NMDA) stimulates the elevation of intracellular calcium concentration ($[Ca^{2+}]_i$), the release of glutamate, the synthesis of NO and an increase of cGMP. Although NO has been shown to stimulate guanylyl cyclase, it is unclear yet whether NO alters the NMDA-induced glutamate release and ${[Ca^{2+}]}_i$ elevation. We showed that the NO synthase inhibitor, NG-monomethyl-L-arginine (NMMA), partially prevented the NMDA-induced release of glutamate and elevation of ${[Ca^{2+}]}_i$ and completely blocked the elevation of cGMP. These effects of NO on glutamate release and [Ca2+]i elevation were unlikely to be secondary to cGMP as the cGMP analogue, dibutyryl cGMP (dBcGMP), did not suppress the effects of NMDA. Rather, dBcGMP slightly augmented the NMDA-induced elevation of ${[Ca^{2+}]}_i$ with no change in the basal level of glutamate or ${[Ca^{2+}]}_i$. The extracellular NO scavenger hydroxocobalamine prevented the NMDA-induced release of glutamate providing indirect evidence that the effect of NO may act on the NMDA receptor. These results suggest that low concentration of NO has a role in maintaining the NMDA receptor activation in a cGMP-independent manner.

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The Effect of Zirconate Addition on the Joint Properties of Epoxy Adhesive for Car Body Assembly (차체 구조용 에폭시 접착제의 접합부 특성에 미치는 Zirconate 첨가효과)

  • Jeung, Eun-Taek;Lee, Hye-Rim;Lee, So-Jeong;Lim, Chang-Young;Seo, Jong-Dock;Kim, Mok-Soon;Kim, Jun-Ki
    • Journal of Welding and Joining
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    • v.31 no.5
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    • pp.71-76
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    • 2013
  • The effect of zirconate having - NH functional group on the T-peel and lap shear strength of $CaCO_3$ containing structural epoxy adhesive for car body assembly was investigated. Curing behavior of epoxy adhesive samples were investigated by differential scanning calorimeter (DSC) techniques. The addition of zirconate up to 7.5 phr did not affect the curing mechanism of epoxy adhesive. While the small amount of zirconate addition less than 1.1 phr increased the cross-linking density, the excess addition of zirconate resulted in the increase of uncross-linked impurity. From the increase of T-peel and lap shear strength and the change of fracture mode from the adhesive failure to the mixed one, it was considered that the small addition of zirconate was effective in improving the adhesion strength of epoxy adhesive to the adherend and inorganic filler surfaces. The formation of uncross-linked impurity with the excess addition of zirconate was considered to decrease the joint strength by decreasing the cohesive strength of the cured epoxy.

Protein Expression Analysis of Halobacillus dabanensis $D-8^T$ Subjected to Salt Shock

  • Feng De Qin;Zhang Bo;Lu Wei Dong;Yang Su Sheng
    • Journal of Microbiology
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    • v.44 no.4
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    • pp.369-374
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    • 2006
  • To investigate the mechanism of salt tolerance of gram-positive moderately halophilic bacteria, two-dimensional gel electrophoresis (2-D PAGE) was employed to achieve high resolution maps of proteins of Halobacillus dabanensis $D-8^T$. Approximately 700 spots of proteins were identified from these 2-D PAGE maps. The majority of these proteins had molecular weights between 17.5 and 66 kDa, and most of them were distributed between the isoelectric points (pI) 4.0 and 5.9. Some protein spots were distributed in the more acidic region of the 2-D gel (pI <4.0). This pattern indicated that a number of proteins in the strain $D-8^T$ are acidic. To understand the adaptation mechanisms of moderately halophilic bacteria in response to sudden environmental changes, differential protein profiles of this strain were investigated by 2-D PAGE and $Imagemaster^{TM}$ 2D Platinum software after the cells were subjected to salt shock of 1 to 25% salinity for 5 and 50 min. Analysis showed 59 proteins with an altered level of expression as the result of the exposure to salt shock. Eighteen proteins had increased expression, S proteins were induced, and the expression of 33 proteins was down-regulated. Eight of the up-regulated proteins were identified using MALDI-TOF/MS and MASCOT, and were similar to proteins involved in signal transduction, proteins participating in energy metabolism pathways and proteins involved in stress.

Isoform-Specific Responses of Superoxide Dismutase to Oxidative Stresses and Hormones in Parquat-Tolerant Rehmannia glutinosa

  • Jamal, Arshad;Yoo, Nam-Hee;Yun, Song-Joong
    • Journal of Crop Science and Biotechnology
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    • v.10 no.1
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    • pp.8-12
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    • 2007
  • All accessions of Rehmannia glutinosa show the unique characteristic of intrinsic tolerance to paraquat. The higher level of endogenous superoxide dismutase(SOD) activity and its increase upon paraquat treatment indicated the involvement of SOD in the tolerance mechanism to paraquat in R. glutinosa. In this study, we examined the isoform-specific response of SOD to oxidative stresses and hormones. Six SOD isoforms were found in the leaf, and they were identified as two MnSODs(named MnSOD I and MnSOD II, in order of increasing mobility), one FeSOD and three Cu/ZnSODs(named Cu/ZnSOD I, Cu/ZnSOD II, and Cu/ZnSOD III, in order of increasing mobility). MnSOD I, MnSOD II, FeSOD, Cu/ZnSOD I, Cu/ZnSOD II, and Cu/ZnSOD III, contributed to 4, 11, 7, 15, 30, and 32% of the total SOD activity, respectively. Total SOD activity levels in the leaf were increased by 4, 24, and 21% by paraquat, salicylic acid(SA), and yeast extract(YE), respectively, but little by ethephon. Six SOD isoforms responded differentially to these stresses and hormones. The activities of all the isoforms were increased by YE and SA except that of MnSOD I which was decreased by SA. The activities of MnSOD I, FeSOD, and CuZnSOD I were increased by paraquat. These results suggest that amelioration of oxidative stresses by SOD is fine-tuned by the differential expression of isoforms in R. glutinosa.

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Reduction of Drying Shrinkage Cracking of Box Culvert for Power Transmission with Shrinkage Reducing Agent (수축저감제 혼입에 따른 전력구 박스구조물의 건조수축균열 저감)

  • Woo, Sang-Kyun;Kim, Ki-Jung;Lee, Yun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.20 no.5
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    • pp.102-108
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    • 2016
  • The purpose of this study is to examine the reduction effect of shrinkage reducing agent for drying shrinkage induced cracking and suggest the method of controlling the cracking in concrete box culvert for power transmission. Based on drying shrinkage cracking mechanism, it is necessary to perform the numerical analysis, which involves shrinkage reducing effect of shrinkage reducing agent. From the numerical results, it is found that cracking behavior for longitudinal direction and transverse direction due to differential drying shrinkage of box culvert can occur and the experimental observation of concrete cracks support the numerical predictions. The shrinkage reducing agent reduced the concrete cracking by 40~50%, which shows the methodology of controlling of drying shrinkage cracks in box culverts in real construction site.

Effect of Corydalis Tuber on the inhibition of proliferation of human uterine leiomyoma cell and apoptotic gene expression (현호색(玄胡索)이 자궁근종세포의 증식 억제와 Apoptosis 관련 유전자 발현에 미치는 영향)

  • Lee, Hee-Jae;Baek, Seung-Hee;Kim, Dong-Chul
    • The Journal of Korean Obstetrics and Gynecology
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    • v.19 no.2
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    • pp.214-225
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    • 2006
  • Purpose : This study was aimed to investigate the inhibitory effect of Corydalis Tuber on the proliferation of human uterine leiomyoma cell and the expression of gene related the mechanism of cell apoptosis. Methods : We counted the number of suvival cells treated with indicated concentration of Corydalis Tuber and investigated cell viability by MTS assay. Furthermore, flow cytometric analyis were used to dissect between necrosis and apoptosis related with cell cycle and then we observed the differential gene expression by western blot analysis. Results : 1) The inhibitory effect on the proliferation of uterine leiomyoma cell treated with Corydalis Tuber was increased in a concentration and time proportional. 2) The result of flow cytometry analysis, subG1 phase arrest related cell apoptosis was not investigated in uterine leiomyoma cell treated Corydalis Tuber but showed G2/M phase prolongation. 3) The gene expression of p27, p21 related cell cycle was increased according to increasing concentration, but p53 was not exchanged. 4) The dephosphorylation of pRb gene were increased dependent on treatment concentration and pro-caspase 3, CDK4 were not exchanged. Conclusion : This study showed that Corydalis Tuber have the inhibitory effect on the proliferation of human uterine leiomyoma cell but the effect was thoughted no relationship with apoptosis. The inhibitory effect was suggested that dephosphorylation of pRb gene induced with increasing p21, p27 prolonged cell division in G2/M phase.

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The effect of Sparganii Rhizoma on the proliferation inhibition of human uterine leiomyoma cell and expression of gene related cell apoptosis (삼릉(三稜)이 자궁근종세포의 증식억제와 세포자멸사 관련 발현에 미치는 영향)

  • Park, Chang-Gun;Baek, Seung-Hee;Kim, Dong-Chul
    • The Journal of Korean Obstetrics and Gynecology
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    • v.19 no.2
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    • pp.199-213
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    • 2006
  • Purpose : This study was aimed to investigate the inhibitory effect of Sparganii Rhizoma on the proliferation of human uterine leiomyoma cells and the expression of gene related the mechanism of cell apoptosis. Methods : This study was evaluated the number of death cells treated with indicated concentration of Sparganii Rhizoma and investigated cell death rate by MTS assay. Furthermore, fluorescence-activated cell sorter analysis and DNA fragmentation assay were used to dissect between necrosis and apoptosis. and then we observed the differential gene expression by western blot analysis. Results :1) The inhibitory effect on the growth of uterine leiomyoma cell treated with Sparganii Rhizoma was increased in a dose dependent manner. 2) As the result of FACS analysis, subG1 phase incrase was observed 23.49% inuterine leiomyoma cell treated with Sparganii Rhizoma at $500\;{\mu}g/ml$ compared to control.. 3) The gene expression of p53, p21 related cell apoptosis was increased according to increasing concentration but p27 was none exchanged. 4) The expression of cyclin A, D and E was decreased in a concentration proportional and then the dephosphorylation of pRb was increased. 5) The character of apoptosis, DNA fragmentation was significantly observed according to increasing concentration. 6) The expression of pro-caspase3 were decreased dependent on treatment concentration and activated PARP took place. Conclusion : The inhibitory effect of Sparganii Rhizoma on the proliferation of human uterine leiomyoma cells was observed with apoptosis and cell cycle arrest. These data suggest that Sparganii Rhizoma might be candidate of medical therapy for uterine leiomyoma.

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A Literature study on the language disturbance (聲音의 生理 病理에 關한 文獻的 考察)

  • Lee, Won-Ju;Kim, Yeon-Jin;Rho, Sek-Seon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.10 no.1
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    • pp.159-184
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    • 1997
  • A Literature study on the language disturbance, the results are as follows; 1. Utterance was closely concerned not only the vocal organs(pharynx, larynx, epiglottis, lips, tongue, vocal cord etc,) but also five viscera{especially heart, lung, kidney etc.) in The Yellow Emperor's Canon of Internal Medicine. It is very like the vocal mechanism in Medical science. 2. In the language disturbance, It is classified with dysarthria and dysphasia in Medical science. But in Oriental medicine, it is expressed the language disturbance as coma-speech lessness, stiff tongue-speechlessness, frightening-speechlessness etc. Especially in Oriental medicine, Non-utterance is called aphasia in literature study. 3. In the concern of the language disturbance and five viscera, $Heart{\cdot}Lung{\cdot}Kidney$ are counted of first importence. In differential diagnosis, It is divided sthenia-syndrome and asthenia-syndrome. Sthenia-syndrome is classified with wind-cold, fire-evil, adverseness of vital energy, stagnation of phlegm, is easy to cure. Asthenia-syndrome is classified with sexual desire, anxiety-meditation, fear, is hard to cure. 4. The pathogenesis of dysphasia originated from two factors; The first internal damages are consumption of body fluid caused by lung-dryness and yin-dificiency of lung & kidney. The second disease caused by exogenous evjls is sluggishness of lung-energy. 5. In many using points of acupuncture of the language disturbance, the order is LI-4(合谷), H-7(神門), K-l(湧泉), L-3(太衝), K-3(太谿), S-6(三陰交), H-5(通里), G-15(아門), C-23(廉泉), S-40(豊降), K-6(照海), L-7(列缺), S-36(足三里) etc.

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Regulations of Reversal of Senescence by PKC Isozymes in Response to 12-O-Tetradecanoylphorbol-13-Acetate via Nuclear Translocation of pErk1/2

  • Lee, Yun Yeong;Ryu, Min Sook;Kim, Hong Seok;Suganuma, Masami;Song, Kye Yong;Lim, In Kyoung
    • Molecules and Cells
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    • v.39 no.3
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    • pp.266-279
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    • 2016
  • The mechanism by which 12-O-tetradecanoylphorbol-13-acetate (TPA) bypasses cellular senescence was investigated using human diploid fibroblast (HDF) cell replicative senescence as a model. Upon TPA treatment, protein kinase C (PKC) ${\alpha}$ and $PKC{\beta}1$ exerted differential effects on the nuclear translocation of cytoplasmic pErk1/2, a protein which maintains senescence. $PKC{\alpha}$ accompanied pErk1/2 to the nucleus after freeing it from $PEA-15pS^{104}$ via $PKC{\beta}1$ and then was rapidly ubiquitinated and degraded within the nucleus. Mitogen-activated protein kinase docking motif and kinase activity of $PKC{\alpha}$ were both required for pErk1/2 transport to the nucleus. Repetitive exposure of mouse skin to TPA downregulated $PKC{\alpha}$ expression and increased epidermal and hair follicle cell proliferation. Thus, $PKC{\alpha}$ downregulation is accompanied by in vivo cell proliferation, as evidenced in 7, 12-dimethylbenz(a)anthracene (DMBA)-TPA-mediated carcinogenesis. The ability of TPA to reverse senescence was further demonstrated in old HDF cells using RNA-sequencing analyses in which TPA-induced nuclear $PKC{\alpha}$ degradation freed nuclear pErk1/2 to induce cell proliferation and facilitated the recovery of mitochondrial energy metabolism. Our data indicate that TPA-induced senescence reversal and carcinogenesis promotion share the same molecular pathway. Loss of $PKC{\alpha}$ expression following TPA treatment reduces pErk1/2-activated SP1 biding to the $p21^{WAF1}$ gene promoter, thus preventing senescence onset and overcoming G1/S cell cycle arrest in senescent cells.

A Numerical Simulation Study of a Heavy Rainfall Event over Daegwallyeong on 31 July 2014 (2014년 7월 31일 대관령에서 발생한 집중호우에 관한 수치모의 연구)

  • Choi, Seung-Bo;Lee, Jae Gyoo
    • Atmosphere
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    • v.26 no.1
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    • pp.159-183
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    • 2016
  • On 31 July 2014, there was a localized torrential rainfall ($58.5mm\;hr^{-1}$) caused by a strong convective cell with thunder showers over Daegwallyeong. In the surface synoptic chart, a typhoon was positioned in the East China Sea and the subtropical high was expanded to the Korean peninsula. A WRF (Weather Research and Forecasting) numerical simulation with a resolution of 1 km was performed for a detailed analysis. The simulation result showed a similar pattern in a reflectivity distribution particularly over the Gangwon-do region, compared with the radar reflectivity. According to the results of the WRF simulation, the process and mechanism of the localized heavy rainfall over Daegwallyeong are as follows: (1) a convective instability over the middle part of the Korean peninsula was enhanced due to the low level advection of warm and humid air from the North Pacific high. (2) There was easterly flow from the coast to the mountainous regions around Daegwallyeong, which was generated by the differential heating of the insolation among Daegwallyeong and the Yeongdong coastal plain, and nearby coastal waters. (3) In addition, westerly flow from the western part of Daegwallyeong caused a strong convergence in this region, generating a strong upward motion combined by an orographic effect. (4) This brought about a new convective cell over Daegwallyeong. And this cell was more developed by the outflow from another thunderstorm cell to the south, and finally these two cells were merged to develop as a strong convective cell with thunder showers, leading to the record breaking maximum rainfall per hour ($58.5mm\;hr^{-1}$) in July.