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71.
Yusuke Sakai Makiko Koike Hideko Hasegawa Kosho Yamanouchi Akihiko Soyama Mitsuhisa Takatsuki Tamotsu Kuroki Kazuo Ohashi Teruo Okano Susumu Eguchi 《PloS one》2013,8(7)
Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions. 相似文献
72.
Band Edge Engineering of Oxide Photoanodes for Photoelectrochemical Water Splitting: Integration of Subsurface Dipoles with Atomic‐Scale Control
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Yasuyuki Hikita Kazunori Nishio Linsey C. Seitz Pongkarn Chakthranont Takashi Tachikawa Thomas F. Jaramillo Harold Y. Hwang 《Liver Transplantation》2016,6(7)
One of the crucial parameters dictating the efficiency of photoelectrochemical water‐splitting is the semiconductor band edge alignment with respect to hydrogen and oxygen redox potentials. Despite the importance of metal oxides in their use as photoelectrodes, studies to control the band edge alignment in aqueous solution have been limited predominantly to compound semiconductors with modulation ranges limited to a few hundred mV. The ability to modulate the flat band potential of oxide photoanodes by as much as 1.3 V, using the insertion of subsurface electrostatic dipoles near a Nb‐doped SrTiO3/aqueous electrolyte interface is reported. The tunable range achieved far exceeds previous reports in any semiconductor/aqueous electrolyte system and suggests a general design strategy for highly efficient oxide photoelectrodes. 相似文献
73.
Yoshiko Onda Rimei Nishimura Aya Morimoto Hironari Sano Kazunori Utsunomiya Naoko Tajima The Diabetes Epidemiology Research International Mortality Study Group 《PloS one》2016,11(3)
Objective
To follow up Japanese patients with type 1 diabetes for a maximum of 40 years to examine when they transitioned from pediatric care to adult care and to explore whether the attending physician, i.e., pediatrician or internist, was associated with prognosis.Methods
Participants consisted of 1,299 patients who had been diagnosed as having type 1 diabetes at less than 15 years old between 1965 and 1979 identified through two nationwide surveys. Patients were classified as having received either pediatric care or adult care at the age of 15 and 30, and were compared for differences in mortality associated with the attending physician.Results
The attending physicians were confirmed for a total of 1,093 patients at the age of 15. Of these patients, 43.8% and 40.3% received pediatric care and adult care, respectively. Of the 569 patients receiving pediatric care, 74.2%, 56.6%, 53.4%, and 51.3% continued with pediatric care at 20, 30, 40, and 50 years old, respectively. The attending physicians (pediatrician or internist) at the age of 15 and 30 had no significant impact on their survival (P = 0. 892, 0.411, respectively).Conclusions
More than half of the patients who had received pediatric care at the age of 15 continued to receive pediatric care even after the age of 30, suggesting that their transition was far from smooth, while the attending physician at the age of both 15 and 30 was not a prognostic factor for mortality. Thus, the timing for transition to adult care in these patients has no relationship with mortality in Japan. 相似文献74.
75.
Kazunori Sato Yuki Yamanaka Yasuharu Asakura 《Bioscience, biotechnology, and biochemistry》2016,80(4):712-718
Extracellular glutamate concentration is a critical determinant of neuronal cell fate. We recently demonstrated that HT22 murine hippocampal cell viability was reduced by exposure to high concentrations of glutamate, whereas low concentrations promoted cell survival. Extracellular signal-regulated kinase (Erk)1/2 activation by glutamate is important for both glutamate-induced cell death and survival. In this study, we investigated the role of glutamate-induced or hydrogen peroxide (H2O2)-induced Erk1/2 activation in HT22 cell fate determination. Glutamate and H2O2 treatment similarly induced early (<1 h) Erk1/2 phosphorylation regardless of concentration. On the other hand, persistent Erk1/2 phosphorylation (16–24 h) was observed only in the presence of excess glutamate. Only the latter contributed to glutamate-induced cell death, which involved metabolic glutamate receptor 5. Our findings suggest that glutamate concentration modulates two distinct phases of Erk1/2 activation, which can explain the glutamate concentration-dependent determination of HT22 cell fate. 相似文献
76.
Kazunori Yoshizawa Charles Lienhard Izumi Yao Rodrigo L. Ferreira 《Entomological Science》2019,22(3):334-338
The divergence date and ancestral distributional area of the psocid subfamily Speleketorinae, which includes taxa with reversed genitalia (female penis and male vagina of Afrotrogla and Neotrogla, tribe Sensitibillini), were estimated. The most basal divergence of the subfamily (between the North American Speleketor and the tribe Sensitibillini) was estimated to have occurred according to the separation between the North American continent and Gondwana, ca. 175 Ma. The most basal divergence of Sensitibillini (between African Afrotrogla + Sensitibilla and Brazilian Neotrogla) was estimated to have occurred according to the split of West Gondwana (separation between the African and South American continents), ca. 127 Ma. The biome of the ancestral distributional area of Sensitibillini (inland of West Gondwana) is believed to be arid to semi‐arid, which might strengthen the reversed sexual selection and then facilitate the origin of preadaptive features related to the evolution of a female penis. All extant Sensitibillini species inhabit carbonatic caves, but geological evidence suggested independent shifts of these genera to the carbonatic cave habitat in the Tertiary/Quaternary. 相似文献
77.
Keisuke Iida Yamato Tsushima Yue Ma Shadi Sedghi Masoud Mai Sakuma Tomomi Yokoyama Wataru Yoshida Kazunori Ikebukuro Kazuo Nagasawa 《Bioorganic & medicinal chemistry》2019,27(8):1742-1746
G-quadruplexes (G4s) are non-B DNA structures present in guanine-rich regions of gene regulatory areas, promoters and CpG islands, but their occurrence and functions remain incompletely understood. Thus, methodology to identify G4 sequences is needed. Here, we describe the synthesis of a novel cyclic hepta-oxazole compound, L1Bio-7OTD (1), bearing a biotin affinity-tag as a tool to pull down G4 structures from mixtures of G4-forming and non G4-forming DNA sequences. We confirmed that it could pull down G4s associated with telomeres, bcl-2 gene, and c-kit gene. 相似文献
78.
Misato of Drosophila melanogaster and Saccharomyces cerevisiae DML1 are conserved proteins having a homologous region with a part of the GTPase family that includes eukaryotic tubulin and prokaryotic FtsZ. We characterized human Misato sharing homology with Misato of D. melanogaster and S. cerevisiae DML1. Tissue distribution of Misato exhibited ubiquitous distribution. Subcellular localization of the protein studied using anti-Misato antibody suggested that it is localized to the mitochondria. Further experiments of fractionating mitochondria revealed that Misato was localized to the outer membrane. The transfection of Misato siRNA led to growth deficiencies compared with control siRNA transfected HeLa cells, and the Misato-depleted HeLa cells showed apoptotic nuclear fragmentation resulting in cell death. After silencing of Misato, the filamentous mitochondrial network disappeared and fragmented mitochondria were observed, indicating human Misato has a role in mitochondrial fusion. To examine the effects of overexpression, COS-7 cells were transfected with cDNA encoding EGFP-Misato. Its overexpression resulted in the formation of perinuclear aggregations of mitochondria in these cells. The Misato-overexpressing cells showed low viability and had no nuclei or a small and structurally unusual ones. These results indicated that human Misato has a role(s) in mitochondrial distribution and morphology and that its unregulated expression leads to cell death. 相似文献
79.
Stress to endoplasmic reticulum of mouse osteoblasts induces apoptosis and transcriptional activation for bone remodeling 总被引:1,自引:0,他引:1
ATF4 is an essential regulator in osteogenesis as well as in stress responses to the endoplasmic reticulum (ER). We addressed a question: Does ER stress to osteoblasts upregulate ATF4 expression? If so, do they exhibit ATF4-mediated bone remodeling or apoptosis? ER stress, induced by Thapsigargin and tunicamycin, elevated a phosphorylated form of eIF2alpha and ATF4, but the cellular fate depended on treatment duration. The treatment for 1h, for instance, activated Runx2, and type I collagen, while the treatment for 24h induced apoptosis. Our observations suggest that there is a threshold for ER stress and osteoblasts present a bi-phasic pattern of their fate. 相似文献
80.
Two isoforms of chicken melanopsins show blue light sensitivity 总被引:1,自引:0,他引:1
Torii M Kojima D Okano T Nakamura A Terakita A Shichida Y Wada A Fukada Y 《FEBS letters》2007,581(27):5327-5331
Melanopsin is a vertebrate non-visual opsin and functions as a circadian photoreceptor in mammalian retinas. Here we found the expression of two kinds of melanopsin genes in the chicken pineal gland and identified the presence of five isoforms derived from these two genes. Reconstitution of the recombinant proteins with 11-cis-retinal revealed that at least two of these melanopsin protein isoforms can function as blue-sensitive photopigments with absorption maxima at 476-484nm. These values are consistent with maximal sensitivities of action spectra determined from the physiological and behavioral studies on mammalian melanopsins. The melanopsin isoforms found in this study may function as pineal circadian photoreceptors. 相似文献