168 research outputs found
Proline-Rich Tyrosine Kinase 2 (Pyk2) Promotes Cell Motility of Hepatocellular Carcinoma through Induction of Epithelial to Mesenchymal Transition
Aims: Proline-rich tyrosine kinase 2 (Pyk2), a non-receptor tyrosine kinase of the focal adhesion kinase (FAK) family, is up-regulated in more than 60% of the tumors of hepatocellular carcinoma (HCC) patients. Forced overexpression of Pyk2 can promote the proliferation and invasion of HCC cells. In this study, we aimed to explore the underlying molecular mechanism of Pyk2-mediated cell migration of HCC cells. Methodology/Principal Findings: We demonstrated that Pyk2 transformed the epithelial HCC cell line Hep3B into a mesenchymal phenotype via the induction of epithelial to mesenchymal transition (EMT), signified by the up-regulation of membrane ruffle formation, activation of Rac/Rho GTPases, down-regulation of epithelial genes E-cadherin and cytokeratin as well as promotion of cell motility in presence of lysophosphatidic acid (LPA). Suppression of Pyk2 by overexpression of dominant negative PRNK domain in the metastatic HCC cell line MHCC97L transformed its fibroblastoid phenotype to an epithelial phenotype with up-regulation of epithelial genes, down-regulation of mesenchymal genes N-cadherin and STAT5b, and reduction of LPA-induced membrane ruffle formation and cell motility. Moreover, overexpression of Pyk2 in Hep3B cells promoted the phosphorylation and localization of mesenchymal gene Hic-5 onto cell membrane while suppression of Pyk2 in MHCC97L cells attenuated its phosphorylation and localization. Conclusion: These data provided new evidence of the underlying mechanism of Pyk2 in controlling cell motility of HCC cells through regulation of genes associated with EMT. © 2011 Sun et al.published_or_final_versio
Women’s overall satisfaction with health facility delivery services in Ghana: a mixed-methods study
Background: Skilled birth delivery has increased up to nearly 74% in Ghana, but its quality has been questioned over the years. As understanding women's satisfaction could be important to improving service quality, this study aimed to determine what factors were associated with women's overall satisfaction with delivery services quantitatively and qualitatively in rural Ghanaian health facilities. Results: This cross-sectional, mixed methods study used an explanatory sequential design across three Ghana Health Service research areas in 2013. Participants were women who had delivered in the preceding 2 years. Two-stage random sampling was used to recruit women for the quantitative survey. Relationships between women's socio-demographic characteristics and their overall satisfaction with health facility delivery services were examined using univariate and multiple logistic regression analyses. For qualitative analyses, women who completed the quantitative survey were purposively selected to participate in focus group discussions. Data from the focus group discussions were analyzed based on predefined and emerging themes. Overall, 1130 women were included in the quantitative analyses and 136 women participated in 15 focus group discussions. Women's mean age was 29 years. Nearly all women (94%) were satisfied with the overall services received during delivery. Women with middle level/junior high school education [adjusted odds ratio (AOR) = 0.50, 95% confidence interval (CI) = (0.26-0.98)] were less likely to be satisfied with overall delivery services compared to women with no education. Qualitatively, women were not satisfied with the unconventional demands, negative attitude, and unavailability of healthcare workers, as well as the long wait time. Conclusions: Although most women were satisfied with the overall service they received during delivery, they were not satisfied with specific aspects of the health services; therefore, higher quality service delivery is necessary to improve women's satisfaction. Additional sensitivity training and a reduction in work hours may also improve the experience of clients
Development of colored alumilite dosimeter
In the ITER (International Thermonuclear Experimental Reactor), in-vessel components such as blanket and divertor, which are installed in the vacuum vessel of the ITER, are maintained by remote handling equipment (RH equipment). The RH equipment for maintenance is operated under sever environmental conditions, such as high temperature (50 approx 100 degC), high gamma-ray radiation (approx 1 kGy/h) in an atmosphere of inert gas or vacuum; therefore many components of the RH equipment must have a suitable radiation resistance efficiency for long time operation (10 approx 100 MGy). Typical components of the RH equipment have been extensively tested under an intensive gamma-ray radiation. Monitoring of the radiation dose of the components of the RH equipment is essential to control the operation period of the RH equipment considering radiation resistance. However, the maximum measurable radiation dose of the conventional dosimeters, such as ionization chamber, liquid, glass and plastic dosimeters are limited to be approximately 1MGy which is too low to monitor the RH equipment for the ITER. In addition, these conventional dosimeters do not involve sufficient radiation resistance against the high gamma-ray radiation as well as are not easy handling and low cost. Based on the above backgrounds, a new dosimeter with bleaching of an azo group dye to be applied to a radiation monitor has been developed for high gamma-ray radiation use. The colored alumilite dosimeter is composed of the azo group dye (-N=N-) in an anodic oxidation layer of aluminum alloy (Al sub 2 O sub 3). It can monitor the radiation dose by measuring the change of the bleaching of azo dye in the Al sub 2 O sub 3 layer due to gamma-ray irradiation. The degree of bleaching is measured as the change of hue (color) and brightness based on the Munsell's colors with a three dimensional universe using spectrophotometer. In the tests, the dependencies such as colors, anodized layer thickness, type of azo dy of the crature and ultraviolet radiation were investigated using the various colored alumilite samples. The followings were clarified from the test results; - a red colored alumilite sample has shown remarkable bleaching change compared with blue and green colored alumilite samples, - the characteristic of bleaching depends on dose rate, - the degree of bleaching of thick-anodized layer sample is lower than that of thin- anodized layer, - the bleaching is activated under high temperature (over 75degC), - there is no effect of ultraviolet radiation (310 approx 410 nm). As a whole, a red colored and a blue colored alumilite samples are suitable to measure under high dose rate and low dose rate conditions, respectively. For example, a red colored alumilite sample made of TAC-RED 105 dye with layer thickness of 25 mu m is measurable up to 70 MGy under high dose rate of 10 kGy/h. On the other hand, a blue colored alumilite sample made of TAC-BLUE RCD dye with layer thickness of 10 mu m is measurable up to 10 kGy under low dose rate of 2 Gy/h. In this paper, the outline of the colored alumilite dosimeter, bleaching mechanism, measurement method and details of the various test results are described
The LIM domains of hic-5 protein recognize specific DNA fragments in a zinc-dependent manner in vitro.
hic-5 protein is a member of the LIM protein family, containing four LIM domains in its C-terminal region. It is mainly localized in focal adhesions and shows striking similarity to paxillin in its LIM domains, although the function of these LIM domains has remained elusive. In the present study, we found that full-length and the C-terminal half of hic-5 protein, including four LIM domains, bound to DNA in a zinc-dependent manner in vitro . Mouse genomic fragments that specifically bound to the hic-5 protein were isolated by successive rounds of hic-5 protein-DNA complex immunoprecipitation and PCR amplification. Seven independent clones were isolated, which contained high amounts of G+A and/or a long A/T tract. A DNA binding protein blot assay revealed the specificity of the interaction between hic-5 protein and the DNA fragment. Using a series of truncated forms of the hic-5 LIM domains, each of the four LIM domains was found to contribute to DNA binding in a distinctive manner
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