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721.
Huy Duong Huu Imamura Kiyoshi Thanh Le Tu Luu Phuong Duc Truong Hoa Thi Le Hanh Thi Ngoc Van Luu Boi Takenaka Norimichi Maeda Yasuaki 《Clean Technologies and Environmental Policy》2016,18(7):2305-2314
Clean Technologies and Environmental Policy - Biodiesel fuel (BDF) is an important alternative fuel because of the carbon neutral nature of biomass and the exhaustion of fossil fuel resources.... 相似文献
722.
Hiromi Yoshida Yuki Hirakawa Yuka Tomiyamaa Yoshiyuki Mizushina 《European Journal of Lipid Science and Technology》2003,105(7):351-358
Peanut seeds (Arachis hypogaea) were roasted for 6, 12, 20, or 30 min at a frequency of 2450 MHz using a microwave oven. The quality characteristics and the compositions of the oils, i.e. their tocopherol distributions and the molecular species of the triacylglycerols (TAGs) were investigated. These results were compared with those of an unroasted oil sample. Only minor increases (p <0.05) in chemical and physical properties of the oils, such as the carbonyl value, the p‐anisidine value and the color development occurred after a prolonged roasting period. Compared to the original level, more than 92 wt‐% tocopherols remained after 30 min of roasting. A modified thin‐layer chromatography argentation procedure provided 12 different groups of TAGs, based on both the degrees of unsaturation and the total fatty acid chain‐length. Although significant increases (p <0.05) generated in these chemical and physical changes of the oils after 20 min of roasting, no significant loss (p >0.05) was observed in the molecular species of the TAGs during microwave roasting. These results indicate that phospholipids may be attributed to the quality characteristics of peanut oils during microwave roasting. 相似文献
723.
Yutaka Hiraoka Kyosuke Imamura Takanori Kadokura Yoshiharu Yamamoto 《Journal of Alloys and Compounds》2010,489(1):42-46
Purpose of this study is to investigate the carbon diffusion behavior in pure molybdenum at relatively low temperatures by means of fracture surface observation. Carbon addition was performed at a temperature of 1273–1373 K with the heating time being changed. Fracture surface of the specimen after carbon addition was examined using SEM and the carbon diffusion distance was estimated from the change of fracture mode as a function of the distance from the surface. Results are summarized as follows. First, the carbon diffusion distance increased approximately linearly with the increase of heating time from 1.2 to 10.8 ks. This relationship does not agree with that obtained at much higher temperatures. From Arrhenius plots of the slope of the straight line and the temperature, activation energy was calculated (155 kJ/mol). Secondly, the carbon diffusion distance estimated in this study was generally larger than that simulated using the data of Rudman, particularly at a longer heating time. 相似文献
724.
Chemical Synthesis of Side-Chain-Hydroxylated Vitamin D3 Derivatives and Their Metabolism by CYP27B1
Ryota Sakamoto Akiko Nagata Haruki Ohshita Yuka Mizumoto Miho Iwaki Dr. Kaori Yasuda Prof. Toshiyuki Sakaki Dr. Kazuo Nagasawa 《Chembiochem : a European journal of chemical biology》2021,22(19):2896-2900
1α,25-Dihydroxyvitamin D3 (abbreviated here as 1,25D3) is a hormonally active form of vitamin D3 (D3), and is produced from D3 by CYP27 A1-mediated hydroxylation at C25, followed by CYP27B1-mediated hydroxylation at C1. Further hydroxylation of 25D3 and 1,25D3 occurs at C23, C24 and C26 to generate corresponding metabolites, except for 1,25R,26D3. Since the capability of CYP27B1 to hydroxylate C1 of side-chain-hydroxylated metabolites other than 23S,25D3 and 24R,25D3 has not been examined, we have here explored the role of CYP27B1 in the C1 hydroxylation of a series of side-chain-hydroxylated D3 derivatives. We found that CYP27B1 hydroxylates the R diastereomers of 24,25D3 and 25,26D3 more effectively than the S diastereomers, but shows almost no activity towards either diastereomer of 23,25D3. This is the first report to show that CYP27B1 metabolizes 25,26D3 to the corresponding 1α-hydroxylated derivative, 1,25,26D3. It will be interesting to examine the physiological relevance of this finding. 相似文献
725.
Yuka Kameda Mamoru Aizawa Taira Sato Michiyo Honda 《International journal of molecular sciences》2021,22(4)
Osteosarcoma has a poor survival rate due to relapse and metastasis. Zoledronic acid (ZOL), an anti-resorptive and anti-tumor agent, is used for treating osteosarcoma. Delivery of ZOL to the target region is difficult due to its high binding affinity to bone minerals. This study developed a novel treatment for osteosarcoma by delivering ZOL to the target region locally and sustainably. In this study, we fabricated a novel bone substitute by loading ZOL on β-tricalcium phosphate (β-TCP). The ZOL-loaded β-TCP (ZOL/β-TCP) would be expected to express the inhibitory effects via both bound-ZOL (bound to β-TCP) and free-ZOL (release from ZOL/β-TCP). To explore the ability to release ZOL from the ZOL/β-TCP, the amount of released ZOL was measured. The released profile indicates that a small amount of ZOL was released, and most of it remained on the β-TCP. Our data showed that ZOL/β-TCP could successfully express the effects of ZOL via both bound-ZOL and free-ZOL. In addition, we examined the biological effects of bound/free-ZOL using osteosarcoma and osteoclasts (target cells). The results showed that two states of ZOL (bound/free) inhibit target cell activities. As a result, ZOL/β-TCP is a promising candidate for application as a novel bone substitute. 相似文献
726.
Mohammed E. Choudhury Yuka Kigami Junya Tanaka 《International journal of molecular sciences》2021,22(8)
With the increasing age of the population, the incidence of Parkinson’s disease (PD) has increased exponentially. The development of novel therapeutic interventions requires an understanding of the involvement of senescent brain cells in the pathogenesis of PD. In this review, we highlight the roles played by microglia in the basal ganglia in the pathophysiological processes of PD. In PD, dopaminergic (DAergic) neuronal degeneration in the substantia nigra pars compacta (SNc) activates the microglia, which then promote DAergic neuronal degeneration by releasing potentially neurotoxic factors, including nitric oxide, cytokines, and reactive oxygen species. On the other hand, microglia are also activated in the basal ganglia outputs (the substantia nigra pars reticulata and the globus pallidus) in response to excess glutamate released from hyperactive subthalamic nuclei-derived synapses. The activated microglia then eliminate the hyperactive glutamatergic synapses. Synapse elimination may be the mechanism underlying the compensation that masks the appearance of PD symptoms despite substantial DAergic neuronal loss. Microglial senescence may correlate with their enhanced neurotoxicity in the SNc and the reduced compensatory actions in the basal ganglia outputs. The dual roles of microglia in different basal ganglia regions make it difficult to develop interventions targeting microglia for PD treatment. 相似文献
727.
Ogawa M Yamamoto S Kousa Y Nakamura F Yukawa R Fukushima A Harasawa A Kondoh H Tanaka Y Kakizaki A Matsuda I 《The Review of scientific instruments》2012,83(2):023109
We have developed a soft x-ray time-resolved photoemission spectroscopy system using synchrotron radiation (SR) at SPring-8 BL07LSU and an ultrashort pulse laser system. Two-dimensional angle-resolved measurements were performed with a time-of-flight-type analyzer. The photoemission spectroscopy system is synchronized to light pulses of SR and laser using a time control unit. The performance of the instrument is demonstrated by mapping the band structure of a Si(111) crystal over the surface Brillouin zones and observing relaxation of the surface photo-voltage effect using the pump (laser) and probe (SR) method. 相似文献
728.
Oxidized LDL (oxLDL) has been shown to activate the sphingomyelinase pathway producing ceramide in vascular smooth muscle
cells. Therefore ceramide, which is a biologically active lipid causing apoptosis in a variety of cells, may be involved in
the apoptotic action of oxLDL. In this study, we examined whether cholesterol enriched diets affected ceramide metabolism
and oxidation product of LDL, represented by degradation of apolipoprotein B-100 (apoB) in apoE-deficient (apoE−/−) mice. ApoE−/− and wild type mice were fed a standard (AIN-76) diet or 1% cholesterol-enriched diet for 8 weeks. Tissue ceramide levels
were analyzed using electrospray tandem mass spectrometry (LC-MS/MS). Ceramide levels in the plasma and the liver of apoE−/− mice were intrinsically higher than those of the wild type. In apoE−/− mice, dietary cholesterol significantly increased several ceramides and degradation products of apoB in plasma compared to
those fed the control diet. Dietary cholesterol did not affect tissue ceramide levels in the wild type mice. Based on these
results, plasma ceramides possibly correlate with the increase in LDL oxidation and are a risk factor for atherosclerosis. 相似文献