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81.
Furuhata S Ando K Oki M Aoki K Ohnishi S Aoyagi K Sasaki H Sakamoto H Yoshida T Ohnami S 《Molecular and cellular biochemistry》2007,298(1-2):125-138
Among the many tissue stem or progenitor cells recently being unveiled, endothelial progenitor cells (EPCs) have attracted
particular attention, not only because of their cardinal role in vascular biology and embryology but also because of their
potential use in the therapeutic development of a variety of postnatal diseases, including cardiovascular and peripheral vascular
disorders and cancer. The aim of this study is to provide some basic and comprehensive information on gene expression of EPCs
to characterize the cells in molecular terms. Here, we focus on EPCs derived from CD34-positive mononuclear cells of human
umbilical cord blood. The EPCs were purified and expanded in culture and analyzed by a high-density oligonucleotide microarray
and real-time RT-PCR analysis. We identified 169 up-regulated and 107 down-regulated genes in the EPCs compared with three
differentiated endothelial cells of human umbilical vein endothelial cells (HUVEC), human lung microvascular endothelial cells
(LMEC) and human aortic endothelial cells (AoEC). It is expected that the obtained list include key genes which are critical
for EPC function and survival and thus potential targets of EPC recognition in vivo and therapeutic modulation of vasculogenesis
in cancer as well as other diseases, in which de novo vasculogenesis plays a crucial role. For instance, the list includes
Syk and galectin-3, which encode protein tyrosine kinase and β-galactoside-binding protein, respectively, and are expressed higher in EPCs than
the three control endothelial cells. In situ hybridization showed that the genes were expressed in isolated cells in the fetal
liver at E11.5 and E14.5 of mouse development. 相似文献
82.
Dielectric relaxation of DNA in aqueous solutions. 总被引:1,自引:0,他引:1
Using a four-electrode cell and a new electronic system for direct detection of the frequency differences specturm of solution impedance, the complex dielectric constant of calf thymus DNA (Mr = 4 × 106) in aqueous NaCl at 10°C is measured at frequencies ranging from 0.2 Hz to 30 kHz. The DNA concentrations are Cp = 0.01% and 0.05%, and the NaCl concentrations are varied from Cs = 10?4 M to 10?3 M. A single relaxation regions is found in this frequency range, the relaxation frequency being 10 Hz at Cp = 0.01% and Cs = 10?3 M. At Cp = 0.05% it is evidenced that the DNA chains have appreciable intermolecular interactions. The dielectric relaxaton time τd at Cp = 0.01% agrees well with the rotational relaxation time estimated from the reduced visocisty on the assumption that the DNA is not representable as a rigid rod but a coiled chain. It is concluded that the dielectric relaxiatioinis ascribed to the rotation of the molecule. Observed values of dielectric increment and other experimental findings are reasonably explained by assuming that the dipole moment of DNA results from the slow counterion fluctuation which has a longer relaxation time than τd. 相似文献
83.
Kohno T Ichikawa H Totoki Y Yasuda K Hiramoto M Nammo T Sakamoto H Tsuta K Furuta K Shimada Y Iwakawa R Ogiwara H Oike T Enari M Schetter AJ Okayama H Haugen A Skaug V Chiku S Yamanaka I Arai Y Watanabe S Sekine I Ogawa S Harris CC Tsuda H Yoshida T Yokota J Shibata T 《Nature medicine》2012,18(3):375-377
84.
Yaoyu Ren Timo Danner Alexandra Moy Martin Finsterbusch Tanner Hamann Jan Dippell Till Fuchs Marius Müller Ricky Hoft André Weber Larry A. Curtiss Peter Zapol Matthew Klenk Anh T. Ngo Pallab Barai Brandon C. Wood Rongpei Shi Liwen F. Wan Tae Wook Heo Martin Engels Jagjit Nanda Felix H. Richter Arnulf Latz Venkat Srinivasan Jürgen Janek Jeff Sakamoto Eric D. Wachsman Dina Fattakhova-Rohlfing 《Liver Transplantation》2023,13(1):2201939
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs. 相似文献
85.
Atsushi Nishikawa Yoshihiko Sakamoto Akihiro Sakatoku Munenori Noguchi Daisuke Tanaka Shogo Nakamura 《Phycological Research》2010,58(2):79-87
Dibucaine, a local anesthetic, is known to induce flagellar excision in Chlamydomonas reinhardtii. Herein, we investigate whether other local anesthetics have similar effects. Tetracaine, bupivacaine, procaine, and lidocaine also caused flagellar excision, although their potencies were lower than that of dibucaine. Bupivacaine, procaine, and lidocaine induced a morphological change in flagella from a rod‐like shape to a disk‐like shape before flagellar excision. Except for lidocaine, these local anesthetics caused cell‐wall shedding in addition to flagellar excision. The anesthetics in order of their median effective concentration (1‐h EC50) for flagellar excision are as follows: dibucaine (1.37 × 10?5 M) < tetracaine (3.16 × 10?5 M) < bupivacaine (4.25 × 10?4 M) < procaine (2.02 × 10?3 M) < lidocaine (3.61 × 10?3 M). In all cases, Ca2+ depletion from the solution inhibited flagellar excision. However, Ca2+‐channel blockers, IP3 receptor antagonists, and inhibitors of phospholipase C did not prevent excision. We suggest that the local anesthetics induce flagellar excision by increasing the fluidity of the flagellar/cell membrane, thereby allowing extracellular Ca2+ to flow into the cell and cause flagellar excision. 相似文献
86.
Ayumu Niida Yoko Kanematsu-Yamaki Tomoko Asakawa Yoshimasa Ishimura Hisashi Fujita Kouta Matsumiya Naoki Nishizawa Yusuke Adachi Taisuke Mochida Kazue Tsuchimori Mariko Yoneyama-Hirozane Junichi Sakamoto Hideki Hirabayashi Hideo Fukui Shiro Takekawa Taiji Asami 《Bioorganic & medicinal chemistry》2018,26(3):566-572
Neuropeptide Y2 receptor (Y2R) agonism is an important anorectic signal and a target of antiobesity drug discovery. Recently, we synthesized a short-length Y2R agonist, PYY-1119 (4-imidazolecarbonyl-[d-Hyp24,Iva25,Pya(4)26,Cha27,36,γMeLeu28,Lys30,Aib31]PYY(23–36), 1) as an antiobesity drug candidate. Compound 1 induced marked body weight loss in diet-induced obese (DIO) mice; however, 1 also induced severe vomiting in dogs at a lower dose than the minimum effective dose administered to DIO mice. The rapid absorption of 1 after subcutaneous administration caused the severe vomiting. Polyethylene glycol (PEG)- and alkyl-modified derivatives of 1 were synthesized to develop Y2R agonists with improved pharmacokinetic profiles, i.e., lower maximum plasma concentration (Cmax) and longer time at maximum concentration (Tmax). Compounds 5 and 10, modified with 20?kDa PEG at the N-terminus and eicosanedioic acid at the Lys30 side chain of 1, respectively, showed high Y2R binding affinity and induced significant body weight reduction upon once-daily administration to DIO mice. Compounds 5 and 10, with their relatively low Cmax and long Tmax, partially attenuated emesis in dogs compared with 1. These results indicate that optimization of pharmacokinetic properties of Y2R agonists is an effective strategy to alleviate emesis induced by Y2R agonism. 相似文献
87.
Moriyasu Tsuchiyama Tatsuji Sakamoto Tomoyuki Fujita Shuichi Murata Haruhiko Kawasaki 《Biochimica et Biophysica Acta (BBA)/General Subjects》2006
Commercially available enzyme preparations were screened for enzymes that have a high ability to catalyze direct ester-synthesis of ferulic acid with glycerol. Only a preparation, Pectinase PL “Amano” produced by Aspergillus niger, feruloylated glycerol under the experimental conditions. The enzyme responsible for the esterification was purified and characterized. This enzyme, called FAE-PL, was found to be quite similar to an A. niger ferulic acid esterase (FAE-III) in terms of molecular mass, pH and temperature optima, substrate specificity on synthetic substrates, and the N-terminal amino acid sequence. FAE-PL highly catalyzed direct esterification of ferulic acid and sinapinic acid with glycerol. FAE-PL could feruloylate monomeric sugars including arabinose, fructose, galactose, glucose, and xylose. We determined the suitable conditions for direct esterification of ferulic acid with glycerol to be as follows: 1% ferulic acid in the presence of 85% glycerol and 5% dimethyl sulfoxide at pH 4.0 and 50 °C. Under these conditions, 81% of ferulic acid could be converted to 1-glyceryl ferulate, which was identified by 1H-NMR. The ability of 1-glyceryl ferulate to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals was higher than that of the anti-oxidant butyl hydroxytoluene. 相似文献
88.
Yeast plasmids resembling 2 micron DNA: regional similarities and diversities at the molecular level. 总被引:4,自引:0,他引:4 下载免费PDF全文
The nucleotide sequence of two Zygosaccharomyces plasmids, pSB2 (5,415 base pairs), isolated from Zygosaccharomyces bailii, and pSM1 (5,416 base pairs), isolated from Zygosaccharomyces fermentati Naganishi, was determined. The predicted amino acid sequences of open reading frames among six yeast plasmids that resemble 2 microns DNA indicated regional sequence similarities among FLP proteins. Greater similarities were seen among Zygosaccharomyces plasmids (pSB2, pSB3, pSR1, and pSM1) than other combinations. A putative recognition site for the FLP enzyme of a Zygosaccharomyces plasmid also showed some conservation, especially in the 4 nucleotides flanking the central spacer region. From comparative studies of the sequences of putative genes of each plasmid, we propose an apparent phylogenetic relationship among yeast plasmids resembling 2 micron DNA. Among the Zygosaccharomyces plasmids, pSB2 and pSR1 are most closely related, since not only were the FLP enzymes of these two plasmids most closely related, but also the amino acid sequence of the putative P gene of pSR1 showed clear homology with that of open reading frame B of pSB2. 相似文献
89.
Treatment of Mid‐Pregnant Mice with KRN633, an Inhibitor of Vascular Endothelial Growth Factor Receptor Tyrosine Kinase,Induces Abnormal Retinal Vascular Patterning in Their Newborn Pups 下载免费PDF全文
Akane Morita Tsutomu Nakahara Naomichi Abe Asami Mori Kenji Sakamoto Tohru Nagamitsu Kunio Ishii 《Birth defects research. Part B, Developmental and reproductive toxicology》2014,101(4):293-299
We previously reported that treatment of mid‐pregnant mice with KRN633, a vascular endothelial growth factor receptor tyrosine kinase inhibitor, caused fetal growth restriction resulting from diminished vascularization in the placenta and fetal organs. In this study, we examined how the treatment of mid‐pregnant mice with KRN633 affects the development and morphology of vascular components (endothelial cells, pericytes, and basement membrane) in the retinas of their newborn pups. Pregnant mice were treated with KRN633 (5 mg/kg) once daily from embryonic day 13.5 until the day of delivery. Vascular components were examined using immunohistochemistry with specific markers for each component. Radial vascular growth in the retina was slightly delayed until postnatal day 4 (P4) in the newborn pups of KRN633‐treated mothers. On P8, compared with the pups of control mothers, the pups of KRN633‐treated mothers exhibited decreased numbers of central arteries and veins and abnormal branching of the central arteries. No apparent differences in pericytes or basement membrane were observed between the pups of control and KRN633‐treated mothers. These results suggest that a critical period for determining retinal vascular patterning is present at the earliest stages of retinal vascular development, and that the impaired vascular endothelial growth factor signaling during this period induces abnormal architecture in the retinal vascular network 相似文献
90.
Coordinate involvement of cysteine protease and nuclease in the executive phase of plant apoptosis 总被引:2,自引:0,他引:2
Kusaka K Tada Y Shigemi T Sakamoto M Nakayashiki H Tosa Y Mayama S 《FEBS letters》2004,578(3):363-367
We have developed an oat cell-free apoptosis system to investigate the execution mechanisms of plant apoptosis. Cell extracts derived from oat tissues undergoing toxin (victorin)-induced apoptosis caused nuclear collapse and internucleosomal DNA fragmentation in isolated nuclei. Pharmacological studies revealed that cysteine protease, which is E-64-sensitive but insensitive to caspase-specific inhibitors, is a crucial component in the morphological change of isolated nuclei, and that nuclease and the cysteine protease act cooperatively to induce the apoptotic DNA laddering. Interestingly, this finding is contrasted with those in well-studied animal cell-free systems in which an apoptotic endonuclease is solely responsible for the DNA fragmentation. 相似文献