scispace - formally typeset
Search or ask a question
Institution

Kyoto University

EducationKyoto, Japan
About: Kyoto University is a education organization based out in Kyoto, Japan. It is known for research contribution in the topics: Population & Catalysis. The organization has 85837 authors who have published 217215 publications receiving 6526826 citations. The organization is also known as: Kyōto University & Kyōto daigaku.


Papers
More filters
Journal Article
TL;DR: The present method has advantages over the high-performance liquid Chromatography/electrochemical detector, gas chromatography/mass spectrometry, and 32P-postlabeling methods in that it allows localization of 8-OHdG to be specified without the risk of artifactual production of 8 -OHdGs during the DNA extraction and hydrolytic processes.

589 citations

Journal ArticleDOI
TL;DR: Since the establishment of the organelle, proteins have been gained, lost, transferred and retargeted as mitochondria have specialized into the spectrum of functional types seen across the eukaryotic tree of life.

589 citations

Journal ArticleDOI
TL;DR: The systematic evolution of the electronic structure and comprehensive analysis of steady-state and transient PL along with photoluminescence excitation (PLE) spectroscopy measurements indicate that two different types of electronically excited states are responsible for the observed emission characteristics.
Abstract: Graphene oxide (GO) is a graphene sheet modified with oxygen functional groups in the form of epoxy and hydroxy groups on the basal plane and various other types at the edges. It exhibits interesting steady-state photoluminescence (PL) properties. For example, low-energy fluorescence in red to near infrared (NIR) wavelengths (from 600– 1100 nm) has been detected for suspensions and solid thin films of as-synthesized GO. 3] In addition, broad luminescence from 400 to 800 nm from oxygen plasma-treated, mechanically exfoliated, single-layer graphene sheet has been reported. Blue fluorescence with a relatively narrow bandwidth when excited with UV irradiation has also been detected from chemically reduced GO (rGO) and graphene quantum dots. 6] Recently, chemically modified GO or rGO with n-butylamine or Mn has also demonstrated PL emission at a range of energies. 10] A detailed explanation of the origin of such variable energy PL in GO has yet to be elucidated. This is partly because the sample preparation and reduction methods varied, making it difficult to compare the results. Herein, we have prepared GO suspensions that exhibit virtually all of the PL features observed by different groups, through careful and gradual reduction of the GO. The systematic evolution of the electronic structure and comprehensive analysis of steady-state and transient PL along with photoluminescence excitation (PLE) spectroscopy measurements indicate that two different types of electronically excited states are responsible for the observed emission characteristics. GO was synthesized using the modified Hummers method, the details of which have been reported. GO usually contains a large fraction of sp hybridized carbon atoms bound to oxygen functional groups, which makes it an insulator. Reduction can be achieved chemically (e.g. hydrazine exposure) or by thermal annealing in inert environments. Photothermal reduction of GO can be achieved by exposing GO samples to a Xenon flash in ambient conditions. In this study, we prepared aqueous GO solutions and subjected them to steady-state Xe lamp irradiation (500 W) with different exposure times of up to three hours. In contrast to reduction by an instantaneous flash, this method provides a controllable, gradual transformation from GO to rGO, allowing exploration of the PL evolution and emission mechanisms from as-synthesized GO to rGO. The deoxygenation of GO after reduction was confirmed by X-ray photoelectron spectroscopy (XPS), as shown in Figure 1. The C 1s signals of the original GO can be deconvoluted into signals for the C=C bond in aromatic rings (284.6 eV), C O bond (286.1 eV), C=O bond (287.5 eV), and C(=O) OH bond (289.2 eV), in agreement with previous assignments. Increased sp carbon bonding with increased reduction time can be clearly measured, which

589 citations

Journal ArticleDOI
TL;DR: The findings that HNE strongly induced intracellular peroxide production, HNE-induced JNK activation was inhibited by pretreatment of the cells with a thiol antioxidant, N-acetylcysteine, and H2O2 significantly activated JNK support the hypothesis that pro-oxidants play a crucial role in the H NE-induced activation of stress signaling pathways.

588 citations

Journal ArticleDOI
TL;DR: Transfection analysis using fusion genes of GAL4DBD with various fragments of the two factors delineated two transcription activation domains which are inducible in response to hypoxia and are localized in the C‐terminal half of HIF1α.
Abstract: Hypoxia-inducible factor 1 alpha (HIF1alpha) and its related factor, HLF, activate expression of a group of genes such as erythropoietin in response to low oxygen. Transfection analysis using fusion genes of GAL4DBD with various fragments of the two factors delineated two transcription activation domains which are inducible in response to hypoxia and are localized in the C-terminal half. Their sequences are conserved between HLF and HIF1alpha. One is designated NAD (N-terminal activation domain), while the other is CAD (C-terminal activation domain). Immunoblot analysis revealed that NADs, which were rarely detectable at normoxia, became stabilized and accumulated at hypoxia, whereas CADs were constitutively expressed. In the mammalian two-hybrid system, CAD and NAD baits enhanced the luciferase expression from a reporter gene by co-transfection with CREB-binding protein (CBP) prey, whereas CAD, but not NAD, enhanced beta-galactosidase expression in yeast by CBP co-expression, suggesting that NAD and CAD interact with CBP/p300 by a different mechanism. Co-transfection experiments revealed that expression of Ref-1 and thioredoxin further enhanced the luciferase activity expressed by CAD, but not by NAD. Amino acid replacement in the sequences of CADs revealed a specific cysteine to be essential for their hypoxia-inducible interaction with CBP. Nuclear translocation of thioredoxin from cytoplasm was observed upon reducing O2 concentrations.

588 citations


Authors

Showing all 86225 results

NameH-indexPapersCitations
Kari Alitalo174817114231
Ralph M. Steinman171453121518
Masayuki Yamamoto1711576123028
Karl Deisseroth160556101487
Kenji Kangawa1531117110059
Takashi Taniguchi1522141110658
Ben Zhong Tang1492007116294
Takeo Kanade147799103237
Yuji Matsuzawa143836116711
Tasuku Honjo14171288428
Kenneth M. Yamada13944672136
Y. B. Hsiung138125894278
Shuh Narumiya13759570183
Kevin P. Campbell13752160854
Junji Tojo13587884615
Network Information
Related Institutions (5)
University of Tokyo
337.5K papers, 10.1M citations

99% related

Nagoya University
128.2K papers, 3.2M citations

99% related

Osaka University
185.6K papers, 5.1M citations

97% related

University of Tsukuba
79.4K papers, 1.9M citations

97% related

Hokkaido University
115.4K papers, 2.6M citations

97% related

Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023234
2022679
20218,533
20208,740
20198,050
20187,932