Ken-ichi Ishibshi

Dr. Ken-ichi Ishibshi

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Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

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

Representative Publications

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29 June 2014 in Critical Care
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JPJulien Poissy
Julien Poissy
BSBoualem Sendid
Boualem Sendid
SDSébastien Damiens
Sébastien Damiens
KIKen-ichi Ishibshi
Ken-ichi Ishibshi
NFNadine François
Nadine François
DPDaniel Poulain
Daniel Poulain
Introduction: Prompt diagnosis of candidaemia and invasive candidosis is crucial to the early initiation of antifungal therapy. The poor sensitivity of blood cultures (BCs) has led to the development of fungal glycan tests as a diagnostic adjunct. We analysed the performance of tests for the detection of circulating β-D-1,3-glucan (BDG) and mannan in the intensive care unit (ICU) setting. Methods: This retrospective, case–control study included 43 ICU patients with candidaemia and 67 controls, hospitalised on the same ward and assessed weekly for yeast colonisation with simultaneous serum sampling; 340 sera taken before and after positive BCs were available for the cases group and 203 for the controls. BDG and mannan levels were determined using the Fungitell® and Platelia™ Candida Ag tests, respectively. Results: BDG was detected early in sera from cases patients but was also present in several sera from controls. Increasing the cut-off from 80 pg/mL to 350 pg/mL and 800 pg/mL resulted in sensitivity/specificity ratios of 0.97/0.31, 0.65/0.74, 0.30/0.86, respectively. Detection of mannan was more specific but lacked sensitivity. No obvious correlation was found between BDG and colonisation, but a trend existed between high colonisation and high BDG. Candidaemia relapses were associated with a rise in BDG and mannan but, in contrast to the transient nature of mannan, BDG persisted up to 7 weeks after positive BCs. Conclusion: A combination of mannan and BDG tests could be used to guide pre-emptive therapeutic decisions in ICU patients.

22 May 2019 in Nutrients
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KIKen-ichi Ishibshi
Ken-ichi Ishibshi
MNMachiko Nishioka
Machiko Nishioka
NOnobuteru onaka
nobuteru onaka
MTMadoka Takahashi
Madoka Takahashi
DYDaisuke Yamanaka
Daisuke Yamanaka
NONaohito Ohno
Naohito Ohno
Euglena gracilis EOD-1, a microalgal strain known for high yields of the β-1, 3-glucan paramylon, is suggested to function as a dietary fiber and enhance immunity. Here, we aimed to investigate the effects of E. gracilis EOD-1 biomass (EOD1BM) ingestion on immunoglobulin A (IgA) antibody titers in saliva, its reactivity, and the health-related quality of life (QOL) in humans. Reacting human immunoglobulin preparations and saliva with paramylon granules revealed the presence of anti-paramylon antibodies in the blood and saliva. We conducted a placebo-controlled, double-blind, crossover study involving 13 healthy subjects who ingested the placebo or EOD1BM for 4 weeks. Saliva was collected from each subject before and after ingestion, and IgA titers and E. gracilis EOD-1 paramylon (EOD1PM) reactivity were compared. In the EOD1BM Ingestion group, the anti-EOD1PM IgA content and titer increased after EOD1BM ingestion. No such change was observed in the Placebo group. Furthermore, the health-related QOL, especially mental health, increased in the EOD1BM Ingestion group. Thus, EOD1BM ingestion led to the production of paramylon (PM)-specific IgA antibody and increased salivary IgA antibody titers. We demonstrate that EOD1BM ingestion enhanced the immunity in the mucosal surface, evoked an antigen-specific response, and increased the health-related QOL, thereby contributing to health improvement.

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YAYoshiyuki Adachi
Yoshiyuki Adachi
MIMasaki Ishii
Masaki Ishii
TKTakashi Kanno
Takashi Kanno
JTJunko Tetsui
Junko Tetsui
KIKen-ichi Ishibshi
Ken-ichi Ishibshi
NONaohito Ohno
Naohito Ohno
Recognition of (1→3)-β-d-glucans (BGs) by invertebrate β-1,3-d-glucan recognition protein (BGRP) plays a significant role in the activation of Toll pathway and prophenoloxidase systems in insect host defense against fungal invasion. To examine the structure diversity of BGRPs for the recognition of physiochemically different BGs, the binding specificity of BGRPs cloned from four different insects to structure different BGs was characterized using ELISA. Recombinant BGRPs expressed as Fc-fusion proteins of human IgG1 bound to the solid phase of BGs. Based on the binding specificities, the BGRPs were categorized into two groups with different ultrastructures and binding characters; one group specifically binds BGs with triple-helical conformation, while the other group recognizes BGs with disordered conformations like single-helical or partially opened triple helix. The BGRPs from the silkworm and the Indian meal moth bound to the BGs with a triple-helical structure, whereas BGRPs from the red flour beetle and yellow mealworm beetle showed no binding to triple-helical BGs, but bound to alkaline-treated BGs that have a partially opened triple-helical conformation. This evidence suggests that the insect BGRPs can distinguish between different conformations of BGs and are equipped for determining the diversity of BG structures.

3 May 2007 in Chemistry Letters
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KIKen-ichi Ishibshi
Ken-ichi Ishibshi
SMSeijiro Matsubara
Seijiro Matsubara
Preparation of fully deuterium-labeled cyclohexene by H/D-exchange reaction was performed efficiently in the presence of ruthenium catalyst under irradiation of microwaves. The reaction proceeds via a repetition of hydroruthenation and β-elimination.

22 December 2016 in Journal of the Electrochemical Society
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RKRyota Kojima
Ryota Kojima
YKYasuo Kimura
Yasuo Kimura
TMTeng Ma
Teng Ma
KIKen-ichi Ishibshi
Ken-ichi Ishibshi
DTDaisuke Tadaki
Daisuke Tadaki
MNMichio Niwano
Michio Niwano
We have fabricated front-side illuminated dye-sensitized solar cells (DSSCs) with a thin film of vertically oriented TiO2 nanotubes used as the negative electrode. The TiO2 nanotube film was formed by anodizing a metallic titanium thin film that was deposited on a transparent conductive oxide (TCO) layer with an intermediate, protective TiO2 layer. We characterized the structural and electronic properties of the formed TiO2 nanotube films. Titanium tetrachloride (TiCl4) treatment was applied on the TiO2 nanotube film to improve the performance of the DSSCs. We have investigated effects of TiCl4 treatment on the solar cell parameters of the DSSCs: short-circuit current density (ISC), open-circuit voltage (Voc), ideal factor (n), series resistance (Rs) and shunt resistance (Rsh). The parameters have been derived by analyzing measured I-V characteristic of the DSSCs on the basis of the method we have previously proposed. We demonstrate that the performance of the DSSCs is improved by TiCl4 treatment. We discuss the effects of TiCl4 treatment on the performance on the basis of the derived cell parameters.

16 October 2007 in Journal of Nanoparticle Research
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SISaori Ishizu
Saori Ishizu
MSMizuki Sekiya
Mizuki Sekiya
KIKen-ichi Ishibshi
Ken-ichi Ishibshi
YNYumi Negami
Yumi Negami
MAMasafumi Ata
Masafumi Ata