博基 近藤

Prof. 博基 近藤

Center for Low-temperature Plasma Sciences, Nagoya University
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Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 December 2013 in PLOS ONE
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FUFumi Utsumi
Fumi Utsumi
HKHiroaki Kajiyama
Hiroaki Kajiyama
KNKae Nakamura
Kae Nakamura
HTHiromasa Tanaka
Hiromasa Tanaka
MMMasaaki Mizuno
Masaaki Mizuno
FKFumitaka Kikkawa
Fumitaka Kikkawa
Nonequilibrium atmospheric pressure plasma (NEAPP) therapy has recently been focused on as a novel medical practice. Using cells with acquired paclitaxel/cisplatin resistance, we elucidated effects of indirect NEAPP-activated medium (NEAPP-AM) exposure on cell viability and tumor growth in vitro and in vivo. Using chronic paclitaxel/cisplatin-resistant ovarian cancer cells, we applied indirect NEAPP-exposed medium to cells and xenografted tumors in a mouse model. Furthermore, we examined the role of reactive oxygen species (ROS) or their scavengers in the above-mentioned EOC cells. We assessed the viability of NOS2 and NOS3 cells exposed to NEAPP-AM, which was prepared beforehand by irradiation with NEAPP for the indicated time. In NOS2 cells, viability decreased by approximately 30% after NEAPP-AM 120-sec treatment (P<0.01). The growth-inhibitory effects of NEAPP-AM were completely inhibited by N-acetyl cysteine treatment, while L-buthionine-[S, R]-sulfoximine, an inhibitor of the ROS scavenger used with NEAPP-AM, decreased cell viability by 85% after NEAPP-AM 60-sec treatment(P<0.05) and by 52% after 120 sec, compared to the control (P<0.01). In the murine subcutaneous tumor-formation model, NEAPP-AM injection resulted in an average inhibition of the NOS2 cell-inoculated tumor by 66% (P<0.05) and NOS2TR cell-inoculated tumor by 52% (P<0.05), as compared with the control. We demonstrated that plasma-activated medium also had an anti-tumor effect on chemo-resistant cells in vitro and in vivo. Indirect plasma therapy is a promising treatment option for EOC and may contribute to a better patient prognosis in the future.

12 March 2012 in Applied Physics Letters
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SISachiko Iseki
Sachiko Iseki
KNKae Nakamura
Kae Nakamura
MHMoemi Hayashi
Moemi Hayashi
Hiromasa TanakaHiromasa Tanaka
Hiromasa Tanaka
博近博基 近藤
博基 近藤
MHMasaru Hori
Masaru Hori
Two independent ovarian cancer cell lines and fibroblast controls were treated with nonequilibrium atmospheric pressure plasma (NEAPP). Most ovarian cancer cells were detached from the culture dish by continuous plasma treatment to a single spot on the dish. Next, the plasma source was applied over the whole dish using a robot arm. In vitro cell proliferation assays showed that plasma treatments significantly decreased proliferation rates of ovarian cancer cells compared to fibroblast cells. Flow cytometry and western blot analysis showed that plasma treatment of ovarian cancer cells induced apoptosis. NEAPP could be a promising tool for therapy for ovarian cancers.

12 June 2013 in Chemical Science
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KYKazuya Yamaguchi
Kazuya Yamaguchi
博近博基 近藤
博基 近藤
JYJunichiro Yamaguchi
Junichiro Yamaguchi
KIKenichiro Itami
Kenichiro Itami
An aerobic oxidative coupling of arenes/alkenes with arylboronic acids (C–H/C–B coupling) using catalytic Pd(II)–sulfoxide–oxazoline (sox) ligand and iron–phthalocyanine (FePc) has been developed. This dual catalyst system enables the synthesis of sterically hindered heterobiaryls and styrene derivatives under air without stoichiometric co-oxidants. Additionally, this chemistry demonstrated an advance toward an enantioselective biaryl coupling through C–H functionalization.

1 May 2012 in Journal of Power Sources
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Journal Article
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SMShunsuke Muto
Shunsuke Muto
KTKazuyoshi Tatsumi
Kazuyoshi Tatsumi
YKYuji Kojima
Yuji Kojima
HOHideaki Oka
Hideaki Oka
博近博基 近藤
博基 近藤
YUYoshio Ukyo
Yoshio Ukyo

17 February 2020 in Nano-Micro Letters
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NSNeelakandan Marath Santhosh
Neelakandan Marath Santhosh
GFGregor Filipič
Gregor Filipič
EKEva Kovacevic
Eva Kovacevic
AJAndrea Jagodar
Andrea Jagodar
JBJohannes Berndt
Johannes Berndt
Uros CvelbarUros Cvelbar
Uros Cvelbar
Incorporating nitrogen (N) atom in graphene is considered a key technique for tuning its electrical properties. However, this is still a great challenge, and it is unclear how to build N-graphene with desired nitrogen configurations. There is a lack of experimental evidence to explain the influence and mechanism of structural defects for nitrogen incorporation into graphene compared to the derived DFT theories. Herein, this gap is bridged through a systematic study of different nitrogen-containing gaseous plasma post-treatments on graphene nanowalls (CNWs) to produce N-CNWs with incorporated and substituted nitrogen. The structural and morphological analyses describe a remarkable difference in the plasma–surface interaction, nitrogen concentration and nitrogen incorporation mechanism in CNWs by using different nitrogen-containing plasma. Electrical conductivity measurements revealed that the conductivity of the N-graphene is strongly influenced by the position and concentration of C–N bonding configurations. These findings open up a new pathway for the synthesis of N-graphene using plasma post-treatment to control the concentration and configuration of incorporated nitrogen for application-specific properties.

11 January 2019 in Physical Review B
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博近博基 近藤
博基 近藤
YAYutaka Akagi
Yutaka Akagi
HKHosho Katsura
Hosho Katsura
We propose a definition of a Z2 topological invariant for magnon spin Hall systems which are the bosonic analog of two-dimensional topological insulators in class AII. The existence of “Kramers pairs” in these systems is guaranteed by pseudo-time-reversal symmetry which is the same as time-reversal symmetry up to some unitary transformation. The Z2 index of each Kramers pair of bands is expressed in terms of the bosonic counterparts of the Berry connection and curvature. We construct explicit examples of magnon spin Hall systems and demonstrate that our Z2 index precisely characterizes the presence or absence of helical edge states. The proposed Z2 index and the formalism developed can be applied not only to magnonic systems but also to other noninteracting bosonic systems.