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71.
In this study, we examined the clinical significance of KRAS and MAPK1 amplification and assessed whether these amplified genes were potential therapeutic targets in type II ovarian carcinoma. Using fluorescence in situ hybridization, immunohistochemistry, and retrospectively collected clinical data, KRAS and MAPK1 amplifications were identified in 9 (13.2%) and 5 (7.4%) of 68 type II ovarian carcinoma tissue samples, respectively. Interestingly, co-amplification of KRAS and MAPK1 seemed to be absent in the type II ovarian carcinomas tested, except one case. Active phospho-ERK1/2 was identified in 26 (38.2%) out of 68 type II ovarian carcinomas and did not correlate with KRAS or MAPK1 amplification. There was no significant relationship between KRAS amplification and overall or progression-free survival in patients with type II ovarian carcinoma. However, patients with MAPK1 amplification had significantly poorer progression-free survival than patients without MAPK1 amplification. Moreover, type II ovarian carcinoma cells with concomitant KRAS amplification and mutation exhibited dramatic growth reduction following treatment with the MEK inhibitor PD0325901. These findings indicate that KRAS/MAPK1 amplification is critical for the growth of a subset of type II ovarian carcinomas. Additionally, RAS/RAF/MEK/ERK pathway-targeted therapy may benefit selected patients with type II ovarian carcinoma harboring KRAS/MAPK1 amplifications.  相似文献   
72.
MicroRNA (miRNA) is a type of non-coding RNA that regulates the expression of its target genes by interacting with the complementary sequence of the target mRNA molecules. Recent evidence has shown that genotoxic stress induces miRNA expression, but the target genes involved and role in cellular responses remain unclear. We examined the role of miRNA in the cellular response to X-ray irradiation by studying the expression profiles of radio-responsive miRNAs and their target genes in cultured human cell lines. We found that expression of miR-574-3p was induced in the lung cancer cell line A549 by X-ray irradiation. Overexpression of miR-574-3p caused delayed growth in A549 cells. A predicted target site was detected in the 3′-untranslated region of the enhancer of the rudimentary homolog (ERH) gene, and transfected cells showed an interaction between the luciferase reporter containing the target sequences and miR-574-3p. Overexpression of miR-574-3p suppressed ERH protein production and delayed cell growth. This delay was confirmed by knockdown of ERH expression. Our study suggests that miR-574-3p may contribute to the regulation of the cell cycle in response to X-ray irradiation via suppression of ERH protein production.  相似文献   
73.
74.
Simple chromatographic methods were applied to terpenoid resins used as gum bases. Five triterpenoid resins, mastic, dammar resin, olibanum, benzoin gum and elemi resin, and two diterpenoid resins, rosin and copal resin, were separated with normal-phase TLC. Characteristic patterns were observed for all resins. Different samples of the same resin gave identical patterns. The TLC method is a candidate for a simple identification test for terpenoids resins. Samples were then methyl-esterified and analyzed with GC/MS. All resins exhibited characteristic chromatograms for total ion current. Major constituents of all resins were detected. Unique constituents that can be used as indicators were found in every resin. Therefore, GC/MS of methyl-esterified terpenoid resins is a valuable identification method.  相似文献   
75.
The tribological properties of cast iron have been investigated to determine the effects of micro-texturing the surfaces. The micro-textured surfaces were prepared by shot blasting or milling using a shaper. The surfaces with groove patterns and mesh patterns had higher friction coefficients than the flat surfaces. The surfaces with dimpled patterns had lower friction coefficients than the flat surfaces. The results indicated that the dimpled pattern had a beneficial effect by decreasing the friction.  相似文献   
76.
Yellow Cameleons are genetically encoded Ca2+ indicators in which cyan and yellow fluorescent proteins and calmodulin work together as a fluorescence (Förster) resonance energy transfer Ca2+-sensor probe. To achieve ultrasensitive Ca2+ imaging for low resting Ca2+ or small Ca2+ transients in various organs, we generated a transgenic mouse line expressing the highest-sensitive genetically encoded Ca2+ indicator (Yellow Cameleon-Nano 15) in the whole body. We then focused on the mechanism of exocytotic events mediated by intracellular Ca2+ signaling in acinar cells of the mice with an agonist and observed them by two-photon excitation microscopy. In the results, two-photon excitation imaging of Yellow Cameleon-Nano 15 successfully visualized intracellular Ca2+ concentration under stimulation with the agonist at nanomolar levels. This is the first demonstration for application of genetically encoded Ca2+ indicators to pancreatic acinar cells. We also simultaneously observed exocytotic events and an intracellular Ca2+ concentration under in vivo condition. Yellow Cameleon-Nano 15 mice are healthy and no significant deteriorative effect was observed on physiological response regarding the pancreatic acinar cells. The dynamic range of 165% was calculated from Rmax and Rmin values under in vivo condition. The mice will be useful for ultrasensitive Ca2+ imaging in vivo.  相似文献   
77.
Photocatalytic activities for hydrogen evolution of lanthanide zirconium oxides, Ln2Zr2O7 (Ln = La, Ce, Nd and Sm) prepared by a solution reaction method were investigated. Under the illumination of 500 W Xenon lamps, hydrogen gas was clearly evolved in a distilled water suspension of La2Zr2O7, Sm2Zr2O7 and Nd2Zr2O7. Under the visible-light illumination, hydrogen gas was evolved in a distilled water suspension of Nd2Zr2O7 and Sm2Zr2O7. From the photoelectrochemical measurements, the values of the flat band potential were estimated to be −0.64, −0.52, −0.31 and +0.04 eV for La2Zr2O7, Sm2Zr2O7, Nd2Zr2O7 and Ce2Zr2O7, respectively, versus the normal hydrogen electrode (NHE). The values of the band gap energy were calculated to be about 3.52, 2.86, 2.67 and 2.53 eV for La2Zr2O7, Sm2Zr2O7, Nd2Zr2O7 and Ce2Zr2O7, respectively. Due to the effect of 4f orbital electrons, the band gap energy of these compounds becomes narrower than in ZrO2 and as a consequence, Sm2Zr2O7 and Nd2Zr2O7 show the photocatalytic activity under the visible-light.  相似文献   
78.
Atherosclerosis is a multifactorial disorder. Recent studies indicate that the plasma level of sphingomyelin, which yields ceramide, correlates with the risk of coronary heart disease. Therefore, ceramide, a well-known lipid causing apoptosis in various cell types, may contribute to atherogenesis. We examined the relationship between ceramide concentration and risk factors of atherosclerosis in normal human plasma using electrospray tandem mass spectrometry (LC-MS/MS). Major ceramides in human plasma were C24∶0 and C24∶1. The ceramide concentration showed a significant positive correlation with total cholesterol (TC) and triglycerides (TG). In addition, plasma ceramide level increased drastically at a high level of LDL cholesterol (more than 170 mg/dL). Our previous studies demonstrated that the sum of fragmented and conjugated apolipoprotein B-100 proteins (B-ox), which were products of a radical reaction of LDL as well as plasma, was a reliable index of atherosclerosis. B-ox showed a significant positive correlation with the plasma ceramide level. Based on these results, we propose that the ceramide level in human plasma is a risk factor at the early stages of atherosclerosis.  相似文献   
79.
The antibacterial activity of [60]fullerene (C60), dissolved with poly(vinylpyrrolidone) K30 (PVP), was studied. Under photo-irradiation, C60/PVP aqueous solutions showed antibacterial activity, whereas PVP solution alone or fullerene solutions in the absence of light showed no activity. These results reveal that C60 is a potentially good device as a photoinduced antibacterial agent.  相似文献   
80.
Contrast-enhanced ultrasonography (arterial infusion) has been clinically established as a qualitative diagnosis imaging tool for hepatocellular carcinoma (HCC). Contrast-enhanced ultrasonography (CEUS) was performed after of Albunex (sonicated serum albumin) or Carbon Dioxide (CO2) microbubble by hand, into the hepatic artery as a diagnostic modality for the early HCC. Here, we discussed the diagnosis of the early HCC by CEUS using Albunex as a contrast medium. Briefly, a diagnosis of the early HCC was made CEUS examination of the hemodynamics of the arteries showed a hypovascular pattern. And tumor size was under 20 mm in diameter, the histopathologic examination was essential to reach a final diagnosis, well-differentiated HCC.  相似文献   
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