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351.
Glioma stem cells (GSCs), the cancer stem cells of glioblastoma multiforme (GBM), contribute to the malignancy of GBM due to their resistance to therapy and tumorigenic potential; therefore, the development of GSC-targeted therapies is urgently needed to improve the poor prognosis of GBM patients. The molecular mechanisms maintaining GSCs need to be elucidated in more detail for the development of GSC-targeted therapy. In comparison with patient-derived GSCs and their differentiated counterparts, we herein demonstrated for the first time that phospholipase C (PLC)ε was highly expressed in GSCs, in contrast to other PLC isoforms. A broad-spectrum PLC inhibitor suppressed the viability of GSCs, but not their stemness. Nevertheless, the knockdown of PLCε suppressed the survival of GSCs and induced cell death. The stem cell capacity of residual viable cells was also suppressed. Moreover, the survival of mice that were transplanted with PLCε knockdown-GSCs was longer than the control group. PLCε maintained the stemness of GSCs via the activation of JNK. The present study demonstrated for the first time that PLCε plays a critical role in maintaining the survival, stemness, and tumor initiation capacity of GSCs. Our study suggested that PLCε is a promising anti-GSC therapeutic target.  相似文献   
352.
Cancer metastasis accounts for most of the mortality associated with solid tumors. However, antimetastatic drugs are not available on the market. One of the important biological events leading to metastasis is the epithelial to mesenchymal transition (EMT) induced by cytokines, namely transforming growth-factor-β (TGF-β). Although several classes of inhibitors targeting TGF-β and its receptor have been developed, they have shown profound clinical side effects. We focused on our synthetic compound, HPH-15, which has shown anti-fibrotic activity via the blockade of the TGF-β Smad-dependent signaling. In this study, 10 μM of HPH-15 was found to exhibit anti-cell migration and anti-EMT activities in non-small-cell lung cancer (NSCLC) cells. Although higher concentrations are required, the anti-EMT activity of HPH-15 has also been observed in 3D-cultured NSCLC cells. A mechanistic study showed that HPH-15 inhibits downstream TGF-β signaling. This downstream inhibition blocks the expression of cytokines such as TGF-β, leading to the next cycle of Smad-dependent and -independent signaling. HPH-15 has AMPK-activation activity, but a relationship between AMPK activation and anti-EMT/cell migration was not observed. Taken together, HPH-15 may lead to the development of antimetastatic drugs with a new mechanism of action.  相似文献   
353.
The Hill plot is a well-known criterion of the f-electron element interatomic threshold distance separating the nonmagnetic state from the magnetic state in actinides and lanthanides. We have reinvestigated the Hill plot of Ce compounds using the commercial crystallographic database CRYSTMET, focusing on a relationship between the Ce-Ce distance and the magnetic ordering temperature because a Ce compound with no other magnetic elements rarely has a magnetic ordering temperature that is higher than 20 K. The Hill plot of approximately 730 compounds has revealed that a Ce compound, particularly a ferromagnet, showing a high magnetic ordering temperature would require a short Ce-Ce distance with a suppression of the valence instability of the Ce ion. From the study, we developed interest in Ce2AuP3 with a Curie temperature of 31 K. The ferromagnetic nature of this material has been examined in terms of a doping effect, which suggests a possible increase in magnetic anisotropy energy.  相似文献   
354.
Metallurgical and Materials Transactions B - Previously this group reported that a good quality titanium metal powder can be produced from titanium sulfides by electrochemical OS process. In this...  相似文献   
355.
Lysine methyl ester (LME), which was generated in situ by the reaction of lysine methyl ester dihydrochloride and triethylamine in dimethyl sulfoxide (DMSO), was prepolymerized with 4,4′‐bismaleimidodiphenylmethane (BMI) at 80°C for 2 h in DMSO. Then, the formed prepolymer was precipitated in water. The obtained LME/BMI prepolymers with molar ratios of 2:2, 2:3, and 2:4 were compression‐molded at a final temperature of 230°C for 2 h to produce cured lysine methyl ester/4,4′‐bismaleimidodiphenylmethane resins (cLBs; cLB22, cLB23, and cLB24, respectively). Fourier transform infrared (FTIR) analyses revealed that the Michael addition reaction of amino groups to the C?C bonds of the maleimide group occurred in addition to the homopolymerization of the maleimide group. The glass‐transition temperature (Tg) and 5% weight loss temperature (T5) of the cured resin increased with increasing BMI feed content, and cLB24 showed the highest Tg (343°C) and T5 (389°C). The flexural strengths (131–150 MPa) and moduli (3.0–3.6 GPa) of the cLBs were comparable to those of the conventionally cured resins of BMI and 4,4′‐diaminodiphenylmethane. Field emission scanning electron microscopy analysis revealed that there was no phase separation for all of the cured resins. Although cLB23 and cLB24 were not biodegradable, cLB22 had a biodegradability of 8.5% after 30 days in an aerobic aqueous medium containing activated sludge. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40379.  相似文献   
356.
Females of the lichen moth, Miltochrista calamina (Arctiidae, Lithosiinae), were previously shown to produce 5-methylheptadecan-7-ol (1) as a sex pheromone. In field tests, males were attracted only by the (5R,7R)-isomer of the four stereoisomers that were prepared by separation from two mixtures of diastereoisomers. A new route to (5R,7R)-1 starting from (S)-propylene oxide was developed utilizing the SN2 reaction of an optically active secondary tosylate and the Jacobsen hydrolytic kinetic resolution of an epoxide intermediate as key steps. Enantioselective HPLC analysis of the product and the antipode synthesized from (R)-propylene oxide confirmed their high enantiomeric excess (> 99 %). Using this stereospecific synthesis, six analogues with the same configuration as (5R,7R)-1 but with different alkyl chain(s) connected to the stereogenic centers were prepared in order to obtain GC/MS data and to examine the ability of M. calamina males to discriminate between them. The mass spectra of the synthetic analogues revealed characteristic fragment ions derived by cleavage around the methyl group in addition to that at the hydroxyl group. In field trapping tests, five out of the six compounds were attractive to male M. calamina moths, indicating that the males distinguished the configurations of methyl and hydroxyl groups but were less able to perceive differences in the lengths of the two alkyl chains in the pheromone.  相似文献   
357.
The objective of the present study is to develop a novel nondestructive, simple, and quick method to evaluate the friction, twist, and gloss of human hair based on near-infrared diffuse reflectance (NIR-DR) spectroscopy and chemometrics. NIR-DR spectra were measured for human hair, which was collected from eleven Japanese women (age 5-44 years), by use of an optical fiber probe. Partial least squares (PLS) regression has been applied to the NIR-DR spectra of human hair after mean centering (MC), standard normal variate (SNV), and first derivative (1d) or second derivative (2d) analysis to develop calibration models that predict the friction, twist, and gloss of human hair. We identified the most suitable wavenumber region for the evaluation of each physical property. Correlation coefficients and standard errors of calibration of the PLS calibration models for the friction, twist, and gloss of hair were calculated to be 0.96 and 0.023, 0.81 and 3.27, and 0.90 and 0.36, respectively. Thus, the calibration models have high accuracy.  相似文献   
358.
359.
The applicability of porous spherical silica (PSS) was evaluated as core particles for pharmaceutical products by comparing it with commercial core particles such as mannitol (NP-108), sucrose and microcrystalline cellulose spheres. We investigated the physical properties of core particles, such as particle size distribution, flow properties, crushing strength, plastic limit, drying rate, hygroscopic property and aggregation degree. It was found that PSS was a core particle of small particle size, low friability, high water adsorption capacity, rapid drying rate and lower occurrence of particle aggregation, although wettability is a factor to be carefully considered. The aggregation and taste-masking ability using PSS and NP-108 as core particles were evaluated at a fluidized-bed coating process. The functional coating under the excess spray rate shows different aggregation trends and dissolution profiles between PSS and NP-108; thereby, exhibiting the formation of uniform coating under the excess spray rate in the case of PSS. This expands the range of the acceptable spray feed rates to coat fine particles, and indicates the possibility of decreasing the coating time. The results obtained in this study suggested that the core particle, which has a property like that of PSS, was useful in overcoming such disadvantages as large particle size, which feels gritty in oral cavity; particle aggregation; and the long coating time of the particle coating process. These results will enable the practical fine particle coating method by increasing the range of optimum coating conditions and decreasing the coating time in fluidized bed technology.  相似文献   
360.
Wrought aluminium alloy, A6016-T4, was welded to cast one ADC12 by a friction stir welding technique. A6016 was set on the advancing side, while ADC12 was on the retreating side based on the pre-tensile test results. The dissimilar welds exhibited lower fatigue strengths than A6016 but higher than that of ADC12. Fatigue strengths increased when the tool was offset into ADC12, which could be explained based on the risk volume concept. When ADC12 was set on the advancing side, the fatigue strengths decreased. Microstructural observation revealed that the macroscopic structure in the stir zone drastically changed by putting ADC12 on the advancing side, and insufficient mixing of dissimilar alloys resulted in the lower fatigue strengths.  相似文献   
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