• Reproductive and Developmental Biology
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• 제36권3호
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• pp.207-212
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• 2012

The shortage of human organs for transplantation has induced the research on the possibility of using animal as porcine. However, pig to human transplantation as known as xeno-transplantation has major problem as immunorejection. Recently, the solutions of pig to human xenotransplantation are commonly mentioned as having a genetically modification which include alpha 1, 3 galatosyl transferase knockout (GTKO) and immune-suppressing gene transgenic model. Unfortunately, the expression level of transgenic gene is very low activity. Therefore, development of gene overexpression system is the most urgent issue. Also, the tissue specific overexpression system is very important. Because most blood vessels are endothelial cells, establishment of the endothelial-specific promoter is attractive candidates for the introduction of suppressing immunorejection. In this study, we focus the ICAM2 promoter which has endothelial-specific regulatory region. To detect the regulatory region of ICAM2 promoter, we cloned 3.7 kb size mini-pig ICAM2 promoter. We conduct serial deletion of 5' flanking region of mini-pig ICAM2 promoter then selected promoter size as 1 kb, 1.5 kb, 2 kb, 2.5 kb, and 3 kb. To analyze promoter activity, luciferase assay system was conducted among these vectors and compare endothelial activity with epithelial cells. The reporter gene assay revealed that ICAM2 promoter has critical activity in endothelial cells (CPAE) and 1 kb size of ICAM2 promoter activity was significantly increased. Taken together, our studies suggest that mini-pig ICMA2 promoter is endothelial cell specific overexpression promoter and among above all size of promoters, 1 kb size promoter is optimal candidate to overcome the vascular immunorejection in pig to human xenotransplantation.

• 대한본초학회지
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• 제22권4호
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• pp.137-143
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• 2007

Objectives : Catalpa ovata G. Don (Bignoniaceae) has been shown to possess a variety of pharmacological activities. However, the effect of Catalpa ovata G. Don on endothelial adhesion molecule expression has not been reported. Methods : To examine the effect of Catalpa ovata G. Don on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs) stimulated with tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), we used various methods such as Western blot analysis, reverse tranascription-polymerase chain reaction (RT-PCR), and luciferase activity assay. Results : 1. The extract of Catalpa ovata G. Don inhibited the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in HUVECs stimulated with TNF-${\alpha}$. 2. The extract of Catalpa ovata G. Don reduced TNF-${\alpha}$-induced adhesion of leukocytes to HUVECs. 3. In addition, The extract of Catalpa ovata G. Don inhibited the promoter activities of ICAM-1 and VCAM-1. Conclusions : These results that Catalpa ovata G. Don may be beneficial in the treatment of inflammatory such as atherosclerosis.

• 한국표면공학회지
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• 제56권1호
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• pp.77-83
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• 2023

The reliability of leadframe-based semiconductor package depends on the adhesion between metal and epoxy molding compound (EMC). In this study, the Ag surface was electrochemically treated in a solution containing silanes in order to improve the adhesion between Ag and epoxy substrate. After electrochemical treatment, the thin silane layer was deposited on the Ag surface, whereby the peel strength between Ag and epoxy substrate was clearly improved. The improvement of peel strength depended on the functional group of silane, implying the chemical linkage between Ag and epoxy.

• International Journal of Oral Biology
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• 제33권4호
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• pp.149-154
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• 2008

Porphyromonas gingivalis, a major periodontal pathogen, has been implicated in the initiation and progression of periodontal disease. Endothelial dysfunction (Editor note: Aberrant and dysfunction are somewhat redundant. The authors may want to choose one or the other.) contributes to chronic periodontal inflammation. Using cDNA-representational difference analysis, we found that P.gingivalis lipopolysaccharide differentially induces a number of genes in human microvascular endothelial cells. Among these upregulated genes, we focused on intercellular adhesion molecule-1 (VCAM-1), which is crucial for leukocyte recruitment during vascular inflammation. P. gingivalis LPS significantly increased the expression of vascular cell adhesion molecule-1 (VCAM-1) as well as ICAM-1. Promoter assays revealed that the transcription of these cell adhesion molecules was mainly regulated by nuclear factor-${\kappa}B$ (NF-${\kappa}B$) in endothelial cells. Furthermore, P. gingivalis LPS significantly increased leukocyte adhesiveness to microvascular endothelial cells and to aortic endothelium. Taken together, our results demonstrate that P. gingivalis LPS activates microvascular endothelial cells through NF-${\kappa}B$-dependent expression of cell adhesion molecules.

• 접착 및 계면
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• 제4권2호
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• pp.21-29
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• 2003

Hot AC anodising has been evaluated us pre-treatment for aluminium prior to structural adhesive bonding. Phosphoric and sulphuric acid hot AC anodising showed very promising adhesion promoter capabilities with durability comparable with the best standard DC anodising procedures. AC anodising does not required etching prior to anodising and offers u pre-treatment time down to 20 seconds. The interface/interphase between the aluminium substrate and the adhesive was investigated in order to get a better understanding of the involved adhesion mechanisms and to explain the long-tenn properties. The alkaline medium formed at the oxide layer/adhesive interface has been shown to induce a partial dissolution of the oxide layer leading to the formation of metallic ions which diffuse in the adhesive (EPMA measurements). The effect of diffusion of the Al ions on adhesion and joint durability is still uncertain but studies showed that pre-bond moisture affected the joints durability and to some extent the diffusion length. specially for DC anodised samples. So far no direct correlation could be established between the diffusion length d and the joints durability but new trials with better control over the elapsed time between bonding and adhesive curing are expected to help getting a better understanding of the involved mechanisms.

• 센서학회지
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• 제5권1호
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• pp.15-22
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• 1996

감광성 고분자를 감지막 재료로 한 FET형 $Ca^{2+}$ sensor(Ca-ISFET)를 micropool법 및 사진식각법으로 제조하였다. 반도체 공정에 쓰이는 negative photoresist인 OMR-83을 감지막 재료로 사용한 경우, micropool법에 있어서는 가소제인 DOA를 포함하므로 좋은 감응 특성을 나타내었으나, 사진식각법에 있어서는 가소제를 사용할 수 없어 부적합하였다. Poly(vinyl butyral)을 감지막 재료로 하고, 사진식각법으로 제조된 Ca-ISFET는 $Ca^{2+}$ 농도 $10^{-4}{\sim}10^{-1}\;mole/{\ell}$ 범위에서 좋은 직선성을 나타내었으며, 감응기울기는 $23{\pm}0.2\;mV/decade$였다. 감지막 재료로서 PVB는 바탕소자인 pH-ISFET wafer 위에 adhesion promoter 용액의 전처리를 하지 않아도 양호한 부착력을 나타내었으며, 가소제 이행의 문제가 없어서 막의 안정성이 좋은 특성이 있었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권5호
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• pp.445-454
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• 2007

Background: Phosphatidic acid(PA), an important second messenger, is involved in inflammation. Notably, cell-cell interactions via adhesion molecules playa central role in inflammation. This thesis show that PA induces expression of intercellular adhesion molecule-1(ICAM-1) on macrophages and describe the signaling pathways. Materials and methods: Macrophages were cultured in the presence of 10% FBS and assayed cell to cell adhesion using HUVEC. For the gene and protein analysis, RT-PCR, Western blot and flow cytometry were performed. In addition, overexpressed cell lines for dominant negative PKC-${\delta}$ mutant established and tested their effect on the promoter activity and expression of ICAM-1 protein by PA. Results: PA-activated macrophages significantly increased adhering to human umbilical vein endothelial cell and this adhesion was mediated by ICAM-1. Pretreatment with rottlerin(PKC-${\delta}$ inhibitor) or expression of a dominant negative PKC-${\delta}$ mutant, but not Go6976(classical PKC-${\alpha}$ inhibitor) and myristoylated PKC-${\xi}$ inhibitor, attenuated PA-induced ICAM-1 expression. The p38 mitogen-activated protein kinase(MAPK) inhibitor blocked PA-induced ICAM-1 expression in contrast, ERK upstream inhibitor didn't block ICAM-1. Conclusion: These data suggest that PA-induced ICAM-1 expression and cell-cell adhesion in macrophages requires PKC-${\delta}$ activation and that PKC-${\delta}$ activation is triggers to sequential activation of p38 MAPK.

• 한국재료학회지
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• 제25권12호
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• pp.719-726
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• 2015

For a decade, solution-processed functional materials and various printing technologies have attracted increasingly the significant interest in realizing low-cost flexible electronics. In this study, Cu nanoparticles are synthesized via the chemical reduction of Cu ions under inert atmosphere. To prevent interparticle agglomeration and surface oxidation, oleic acid is incorporated as a surface capping molecule and hydrazine is used as a reducing agent. To endow water-compatibility, the surface of synthesized Cu nanoparticles is modified by a mixture of carboxyl-terminated anionic polyelectrolyte and polyoxylethylene oleylamine ether. For reducing the surface tension and the evaporation rate of aqueous Cu nanoparticle inks, the solvent composition of Cu nanoparticle ink is designed as DI water:2-methoxy ethanol:glycerol:ethylene glycol = 50:20:5:25 wt%. The effects of poly(styrene-co-maleic acid) as an adhesion promoter(AP) on rheology of aqueous Cu nanoparticle inks and adhesion of Cu pattern printed on polyimid films are investigated. The 40 wt% aqueous Cu nanoparticle inks with 0.5 wt% of Poly(styrene-co-maleic acid) show the "Newtonian flow" and has a low viscosity under $10mPa{\cdots}S$, which is applicable to inkjet printing. The Cu patterns with a linewidth of $50{\sim}60{\mu}m$ are successfully fabricated. With the addition of Poly(styrene-co-maleic acid), the adhesion of printed Cu patterns on polyimid films is superior to those of patterns prepared from Poly(styrene-co-maleic acid)-free inks. The resistivities of Cu films are measured to be $10{\sim}15{\mu}{\Omega}{\cdot}cm$ at annealing temperature of $300^{\circ}C$.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권5호
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• pp.518-524
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• 2008

Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

• Nutrition Research and Practice
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• 제1권1호
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• pp.19-28
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• 2007

To identify regulatory molecules which play key roles in the development of obesity, we investigated the transcriptional profiles in 3T3-L1 cells at early stage of differentiation and analyzed the promoter sequences of differentially regulated genes. One hundred and sixty-one (161) genes were found to have significant changes in expression at the 2nd day following treatment with differentiation cocktail. Among them, 86 transcripts were up-regulated and 75 transcripts were down-regulated. The 161 transcripts were classified into 10 categories according to their functional roles; cytoskeleton, cell adhesion, immune, defense response, metabolism, protein modification, protein metabolism, regulation of transcription, signal transduction and transporter. To identify transcription factors likely involved in regulating these differentially expressed genes, we analyzed the promoter sequences of up- or - down regulated genes for the presence of transcription factor binding sites (TFBSs). Based on coincidence of regulatory sites, we have identified candidate transcription factors (TFs), which include those previously known to be involved in adipogenesis (CREB, OCT-1 and c-Myc). Among them, c-Myc was also identified by our microarray data. Our approach to take advantage of the resource of the human genome sequences and the results from our microarray experiments should be validated by further studies of promoter occupancy and TF perturbation.