Study on the resin layer formation according to the imprinting pressure rates.

The UV imprinting period and pressure magnitude are very important processing factors along with pattern shape and density of mold pattern. In the control process of the residual resin layer, the imprinting period and the magnitude and rate of the imprinting pressure should be properly assigned according to the density and shape of the mold pattern as well as resin viscosity etc. In this work, the imprinting time and pressure rate are studied for the formation and thickness variation of the residual resin layer. The thickness variation of the resin layer during imprinting process is computed according to the variation of the imprinting load rate, and some comparison results are successfully obtained with a 3-D shape of the mold patterns.

Study on the resin temperature developments during UV imprinting process.

During the imprinting process, the temperature of the UV resin increases as the phase of the resin changes from fluid into solid. During UV curing, some amount of heat is released from inside the resin and transferred into contacting materials. The heat flow is measured with photo-DSC, and other related thermal and mechanical properties of the resin. With the measured material properties, the temperature developments both inside of the resin layer and along the interfaces of the contacting materials are computed. During the UV exposure period, the thermal deformation of the mold, which directly influences the pattern distortion are investigated. Under this condition, the developments of strain and temperature inside the mold structure including the UV resin of 3-D shape are computed with the transient time scale during UV curing according to the thickness of resin layer. These computational results are expected to provide useful information for better designs of the imprinting mold and the process condition.

Modulation of the genomic estrogen receptor pathway by water extracts of Cirsium japonicum.

We investigated the estrogenic activity of Cirsium japonicum water extracts, which have long been used to treat vascular-related diseases. The activity of the extracts was characterized in a transient transfection system, using estrogen receptor isoforms and estrogen-responsive luciferase plasmids in HEK 293 cells. The extract activated both and estrogen receptors. Activation was inhibited by the estrogen receptor antagonist ICI 182,780, indicating that the effects were mediated through the estrogen receptor isoforms. Treatment with the extracts increased expression of the progesterone receptor and pS2 genes and expression of estrogen receptor was decreased in MCF-7 cells. These results suggested that the Cirsium japonicum water extracts showed estrogenic effects and may be a potential clinical application for treatment of estrogen related vascular diseases.

Development of an efficient endothelial cell specific vector using promoter and 5' untranslated sequences from the human preproendothelin-1 gene.

We report here, that a vector constructed based on ppET-1 gene promoter and 5' untranslated region induced a high level of gene expression in endothelial cells and the specificity is even further enhanced under hypoxia-mimic conditions due to a natural hypoxia responsive element within the promoter region. A naked DNA vector that confers endothelial cell specific gene expression as well as efficient levels of gene expression was constructed with an endothelial cell specific naked DNA vector, pETlong, by using the full length promoter of the preproendothelin-1 gene and the entire 5' untranslated region upstream from the start codon. Inclusion of the entire 5' untranslated region in pETlong increased gene expression 2.96 fold as compared with that from pETshort, which contains only the promoter sequences. Reporter gene expression from pETlong was 7.9 fold higher as compared with that from CMV-driven promoter based vector in calf pulmonary endothelial cells. However, in nonendothelial COS cells, luciferase activity from pETlong was only 0.3 fold as compared with that of CMV-based vector. Similar results were observed in other nonendothelial cells. These results demonstrate that the pETlong drives gene expression in endothelial cells with high efficacy and specificity. We have examined hypoxia responsiveness of pETlong as the promoter region of the preproendothelin-1 gene contains hypoxia responsive elements. The activity of the pETlong vector was increased 1.6 fold under hypoxia-mimic conditions using cobalt chloride. The high levels of hypoxia-inducible expression in endothelial cells relative to the low levels of background expression in other cells shows that pETlong could be a useful tool for vascular targeting of vascular disease and cancer gene therapy.

A ginsenoside-Rh1, a component of ginseng saponin, activates estrogen receptor in human breast carcinoma MCF-7 cells.

We have examined the possibility that a component of Panax ginseng, ginsenoside-Rh1, acts by binding to steroid hormone receptors such as receptors for estrogen, glucocorticoid, androgen, and retinoic acid. Ginsenoside-Rh1 activated the transcription of the estrogen-responsive luciferase reporter gene in MCF-7 breast cancer cells at a concentration of 50 microM. Activation was inhibited by the specific estrogen receptor antagonist ICI 182,780, indicating that the estrogenic effect of ginsenoside-Rh1 is estrogen receptor dependent. Ginsenoside-Rh1 induction of luciferase activity was dose-dependent in CV-1 cells transiently transfected with estrogen receptor and reporter plasmids. Next, we evaluated the ability of ginsenoside-Rh1 to induce the estrogen-responsive genes in MCF-7 cells. Ginsenoside-Rh1 increased c-fos and pS2 at the mRNA levels at 24h after treatment, although the effects were not as prominent as 17beta-estradiol. Western blot analysis showed that progesterone receptor protein was induced at 24h of treatment of ginsenoside-Rh1. However, ginsenoside-Rh1 failed to activate the glucocorticoid receptor, the androgen receptor, or the retinoic acid receptor in CV-1 cells transiently transfected with the corresponding steroid hormone receptors and hormone responsive reporter plasmids. These data support our hypothesis that ginsenoside-Rh1 acts as a weak phytoestrogen, presumably by binding and activating the estrogen receptor.

Ginsenoside-Rb1 acts as a weak phytoestrogen in MCF-7 human breast cancer cells.

Ginseng has been recommended to alleviate the menopausal symptoms, which indicates that components of ginseng very likely contain estrogenic activity. We have examined the possibility that a component of Panax ginseng, ginsenoside-Rb1, acts by binding to estrogen receptor. We have investigated the estrogenic activity of ginsenoside-Rb1 in a transient transfection system using estrogen-responsive luciferase plasmids in MCF-7 cells. Ginsenoside-Rb1 activated the transcription of the estrogen-responsive luciferase reporter gene in MCF-7 breast cancer cells at a concentration of 50 microM. Activation was inhibited by the specific estrogen receptor antagonist ICI 182,780, indicating that the estrogenic effect of ginsenoside-Rb1 is estrogen receptor dependent. Next, we evaluated the ability of ginsenoside-Rb1 to induce the estrogen-responsive gene c-fos by semi-quantitative RT-PCR assays and Western analyses. Ginsenoside-Rb1 increased c-fos both at mRNA and protein levels. However, ginsenoside-Rb1 failed to activate the glucocorticoid receptor, the retinoic acid receptor, or the androgen receptor in CV-1 cells transiently transfected with the corresponding steroid hormone receptors and hormone responsive reporter plasmids. These data support our hypothesis that ginsenoside-Rb1 acts a weak phytoestrogen, presumably by binding and activating the estrogen receptor.