EPA, an omega‐3 fatty acid, induces apoptosis in human pancreatic cancer cells: Role of ROS accumulation, caspase‐8 activation, and autophagy induction

Fukui, Masayuki,Kang, Ki Sung,Okada, Kazushi,Zhu, Bao Ting Wiley Subscription Services, Inc., A Wiley Company 2013 Journal of cellular biochemistry Vol.114 No.1

<P><B>Abstract</B></P><P>In a recent study, we showed that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two common omega‐3 fatty acids, can cause ROS accumulation and subsequently induce caspase‐8‐dependent apoptosis in human breast cancer cells (Kang et al. [2010], PLoS ONE 5: e10296). In this study, we showed that the pancreas has a unique ability to accumulate EPA at a level markedly higher than several other tissues analyzed. Based on this finding, we sought to further investigate the anticancer actions of EPA and its analog DHA in human pancreatic cancer cells using both in vitro and in vivo models. EPA and DHA were found to induce ROS accumulation and caspase‐8‐dependent cell death in human pancreatic cancer cells (MIA‐PaCa‐2 and Capan‐2) in vitro. Feeding animals with a diet supplemented with 5% fish oil, which contains high levels of EPA and DHA, also strongly suppresses the growth of MIA‐PaCa‐2 human pancreatic cancer xenografts in athymic nude mice, by inducing oxidative stress and cell death. In addition, we showed that EPA can concomitantly induce autophagy in these cancer cells, and the induction of autophagy diminishes its ability to induce apoptotic cell death. It is therefore suggested that combination of EPA with an autophagy inhibitor may be a useful strategy in increasing the therapeutic effectiveness in pancreatic cancer. J. Cell. Biochem. 114: 192–203, 2012. © 2012 Wiley Periodicals, Inc.</P>

Analysis of the Formation of Protoplasts and Regeneration of Cells in Phycomyces blakesleeanus

Fukui, Joe,Choi, Kwan Sam,Miyazaki, Atsushi,Ootaki, Tamotsu,Oikawa, Taneaki 한국미생물 · 생명공학회 2001 Journal of microbiology and biotechnology Vol.11 No.1

It is possible to prepare protoplasts of the zygomycete fungus, Phycomyces blakesleeanus, by digesting the cell wall of spore germlings with commercially available chitinase and chitosanase. However, the cells without any cell walls immediately form large aggregates, and thus, it is difficult to isolate the individually separated protoplasts. Inherent problem with the formation of aggregates in preparing protoplasts could be solved by the use of bovine serum albumin (BSA). As a result, we were able to prepare a large number of single protoplasts quickly and easily. We took time-lapse photomicrographs of the formation of protoplasts, and found that there were certain regions of the cell wall of spore germlings that were sensitive to chitinase and chitosanase, although the cell wall of the original spores is known to be insensitive to these enzymes. There are two kinds of cell walls on a spore germling; one with a bound wheat germ agglutinin (WGA), and the other a bound concanavalin A (ConA). Furthermore, only cells with walls which had bound WGA were able to regenerate, while those with walls with bound ConA were not able to regenerate.

Regioselective phenylene-fusion reactions of Ni( <small>II</small> )-porphyrins controlled by an electron-withdrawing <i>meso</i> -substituent

Fukui, Norihito,Lee, Seung-Kyu,Kato, Kenichi,Shimizu, Daiki,Tanaka, Takayuki,Lee, Sangsu,Yorimitsu, Hideki,Kim, Dongho,Osuka, Atsuhiro Royal Society of Chemistry 2016 Chemical science Vol.7 No.7

<▼1><P>Oxidation of 10,15,20-triaryl Ni(<SMALL>II</SMALL>)-porphyrins bearing an electron-withdrawing substituent at the 5-position with DDQ and FeCl<SUB>3</SUB> gave 10,12- and 18,20-doubly phenylene-fused Ni(<SMALL>II</SMALL>)-porphyrins regioselectively.</P></▼1><▼2><P>Oxidation of 10,15,20-triaryl Ni(<SMALL>II</SMALL>)-porphyrins bearing an electron-withdrawing substituent at the 5-position with DDQ and FeCl<SUB>3</SUB> gave 10,12- and 18,20-doubly phenylene-fused Ni(<SMALL>II</SMALL>)-porphyrins regioselectively. A doubly phenylene-fused <I>meso</I>-chloro porphyrin thus prepared was reductively coupled to give a <I>meso</I>–<I>meso</I> linked dimer, which was further converted to a quadruply phenylene-fused <I>meso</I>–<I>meso</I>, β–β, β–β triply linked Zn(<SMALL>II</SMALL>)–diporphyrin <I>via</I> inner-metal exchange followed by oxidation with DDQ and Sc(OTf)<SUB>3</SUB>. As compared to the usual <I>meso</I>–<I>meso</I>, β–β, β–β triply linked Zn(<SMALL>II</SMALL>)-diporphyrin, this π-extended porphyrin dyad exhibits a smaller HOMO–LUMO gap and a larger two-photon absorption cross-section.</P></▼2>

Effect of Bead Device Diameter on Z-Resolution Measurement in Tomosynthesis Images: A Simulation Study

Fukui Ryohei,Miho Numata,Saki Nishioka,Ryutarou Matsuura,Katsuhiro Kida,Sachiko Goto 한국의학물리학회 2022 의학물리 Vol.33 No.4

Purpose: To clarify the relationship between the diameter of the simulated bead and the Z-resolution of the tomosynthesis image. Methods: A simulated bead was placed on a 1,024×1,024×1,024-pixel base image. The diameters were set to 0.025, 0.05, 0.1, 0.2, 0.3, 0.7, 1.0, and 1.3 mm. A bead was placed at the center of the base image and projected at a simulated X-ray angle range of ±45° to obtain a projected image. A region of interest was placed at the center of the bead image and the slice sensitivity profile (SSP) was obtained by acquiring pixel values in the z-direction. The full width at half maximum of the SSP was defined as the Z-resolution and the frequency response was obtained by the 1-D Fourier transform of the SSP. Results: Z-resolution increased with increasing bead diameter. However, there was no change in Z-resolution between 0.025 and 0.1 mm. The frequency response was similar to that of the Z-resolution, with a significant difference between 0.1 and 0.2 mm diameter. Conclusions: Z-resolution is dependent on the diameter of the bead, which should be selected considering the pixel size of the tomosynthesis image.

Highly planar diarylamine-fused porphyrins and their remarkably stable radical cations

Fukui, N.,Cha, W.,Shimizu, D.,Oh, J.,Furukawa, K.,Yorimitsu, H.,Kim, D.,Osuka, A. THE ROYAL SOCIETY OF CHEMISTRY 2017 Chemical science Vol.8 No.1

<P>Oxidative fusion reactions of meso-phenoxazino Ni(II) porphyrin were found to be temperature dependent, giving rise to either a doubly phenylene-fused product at room temperature or a singly phenoxazine-fused product at 70 degrees C. The latter was further oxidized to a doubly phenoxazine-fused Ni(II) porphyrin, which was subsequently converted to the corresponding free base porphyrin and Zn(II) porphyrin. Compared to previously reported diphenylamine-fused porphyrins that displayed a molecular twist, doubly phenoxazine-fused porphyrins exhibited distinctly different properties owing to their highly planar structures, such as larger fluorescence quantum yields, formation of an offset face-to-face dimer both in solution and the solid state, and the generation of a mixed-valence p-radical cation dimer upon electrochemical oxidation. One-electron oxidation of the phenoxazine-fused Ni(II) porphyrin with Magic Blue gave the corresponding radical cation, which was certainly stable and could be isolated by separation over a silica gel column but slowly chlorinated at the reactive beta-positions in the solid state. This finding led to us to examine beta, beta'-dichlorinated phenoxazine-fused and diphenylamine-fused Ni(II) porphyrins, which, upon treatment with Magic Blue, provided remarkably stable radical cations to an unprecedented level. It is actually possible to purify these radical cations by silica gel chromatography, and they can be stored for over 6 months without any sign of deterioration. Moreover, they exhibited no degradation even after the CH2Cl2 solution was washed with water. However, subtle structural differences (planar versus partly twisted) led to different crystal packing structures and solid-state magnetic properties.</P>

Porphyrin Arch-Tapes: Synthesis, Contorted Structures, and Full Conjugation

Fukui, Norihito,Kim, Taeyeon,Kim, Dongho,Osuka, Atsuhiro American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.26

<P>Porphyrin tapes possessing meso-meso beta-beta beta-beta triple direct linkages have been targets of extensive studies because of their fully conjugated characteristic pi-electronic networks. In this paper, we report porphyrin arch tapes that bear additional carbonyl group(s) or methylene group(s) inserted between one of the beta-beta linkage(s) of the porphyrin tapes. The carbonyl-inserted porphyrin arch-tapes were efficiently synthesized by double fusion reactions of beta-to-beta carbonyl-bridged porphyrin oligomers with DDQ and Sc(OTf)(3), and were converted to the methylene-bridged porphyrin arch-tapes via Luche reduction with NaBH4 and CeCl3 followed by ionic hydrogenation with HBF4 center dot OEt2 and BH3 center dot NEt3. While the conventional porphyrin tapes display rigid and planar structures and low solubilities, these porphyrin arch-tapes show remarkably contorted structures, flexible conformations, and improved solubilities because of the presence of the incorporated seven-membered ring(s). Interestingly, the methylene inserted arch-tapes exhibited conjugative electronic interactions that were comparable to those of porphyrin tapes probably owing to through-space interaction in the contorted conformations. The carbonyl-inserted arch-tapes displayed distinctly larger conjugative interactions owing to an active involvement of the carbonyl group(s) in the electronic conjugation. A similar trend was observed in the nonlinear optical properties, as evidenced by their two-photon absorption cross sections. Furthermore, as a benefit of the contorted structures, these porphyrin arch-tapes can catch C-60 fullerene effectively. Naturally, the electron-rich methylene-bridged arch-tapes exhibited larger association constants than the electron-deficient carbonyl-bridged arch-tapes. Among these arch-tapes, a methylene-bridged syn-Ni(II) porphyrin trimer recorded the largest association constant of (1.5 +/- 0.4) X 10(7) M-1 in toluene at 25 degrees C.</P>

Effect of the Number of Projected Images on the Noise Characteristics in Tomosynthesis Imaging

Fukui, Ryohei,Matsuura, Ryutaro,Kida, Katsuhiro,Goto, Sachiko Korean Society of Medical Physics 2021 의학물리 Vol.32 No.2

Purpose: In this study, we investigated the relationship between the noise characteristics and the number of projected images in tomosynthesis using a digital phantom. Methods: The digital phantom consisted of a columnar phantom in the center of the image and a spherical phantom with a diameter of 80 pixels. A virtual scan was performed, and 128 projected images (Tomo_w/o) of the phantoms were obtained. The image noise according to the Poisson distribution was added to the projected images (Tomo_×1). Furthermore, another projected image with additional noise was prepared (Tomo_×1/2). For each dataset, we created datasets with 64 (half) and 32 (quarter) projections by removing the even-numbered images twice from the 128 (fully) projected images. Tomosynthesis images were reconstructed by filtered back projection (FBP). The modulation transfer function (MTF) was estimated using the sphere method, and the noise power spectrum (NPS) was estimated using the two-dimensional Fourier transform method. Results: The MTFs did not change between datasets, and the NPSs improved as the number of projected images increased. The noise characteristics of the Tomo_×1_half images were the same as those of the Tomo_×1/2_full. Conclusions: To achieve a reduction in the patient dose in tomosynthesis acquisition, we recommend reducing the number of projected images rather than reducing the dose per projection.

Tongguk chŏngun and the Phonological System of Middle Korean

Fukui Rei 훈민정음학회 2012 Scripta Vol.0 No.4

This paper discusses how the reformed system of Sino-Korean, Tongguk chŏngun, was accommodated into the phonological system of Middle Korean. Tongguk chŏngun readings of characters are usually regarded as artificial but in this paper it is emphasized that they were expected to be learnt and correctly pronounced by everyone who wished to learn the newly created alphabet. By examining various seemingly artificial elements such as entering tone ending -rq, geminate consonants, vowels including a rounded palatal medial sound and so on, it is concluded that the system of Tongguk chŏngun uses only those sounds that are already existing in the native Korean vocabulary, thereby tolerating the constraints on the possible position of occurrence.

Visual uncertainty - Freedom

( Fukui Isson ) 한국기초조형학회 2019 한국기초조형학회 작품집 Vol.2019 No.1

OGLE-2012-BLG-0563Lb: A SATURN-MASS PLANET AROUND AN M DWARF WITH THE MASS CONSTRAINED BY<i>SUBARU</i>AO IMAGING

Fukui, A.,Gould, A.,Sumi, T.,Bennett, D. P.,Bond, I. A.,Han, C.,Suzuki, D.,Beaulieu, J.-P.,Batista, V.,Udalski, A.,Street, R. A.,Tsapras, Y.,Hundertmark, M.,Abe, F.,Bhattacharya, A.,Freeman, M.,Itow, IOP Publishing 2015 The Astrophysical journal Vol.809 No.1

<P>We report the discovery of a microlensing exoplanet OGLE-2012-BLG-0563Lb with the planet-star mass ratio of similar to 1 x 10(-3). Intensive photometric observations of a high-magnification microlensing event allow us to detect a clear signal of the planet. Although no parallax signal is detected in the light curve, we instead succeed at detecting the flux from the host star in high-resolution JHK'-band images obtained by the Subaru/AO188 and Infrared Camera and Spectrograph instruments, allowing us to constrain the absolute physical parameters of the planetary system. With the help of spectroscopic information about the source star obtained during the high-magnification state by Bensby et al., we find that the lens system is located at 1.3(-0.8)(+0.6) kpc from us, and consists of an M dwarf (0.34(-0.20)(+0.12)M(circle dot)) orbited by a Saturn-mass planet (0.39(-0.23)(+0.14)M(Jup)) at the projected separation of 0.74(-0.42)(+0.26)AU (close model) or 4.3(-2.5)(+1.5)AU (wide model). The probability of contamination in the host star's flux, which would reduce the masses by a factor of up to three, is estimated to be 17%. This possibility can be tested by future high-resolution imaging. We also estimate the (J - K-s) and (H - K-s) colors of the host star, which are marginally consistent with a low metallicity mid-to-early M dwarf, although further observations are required for the metallicity to be conclusive. This is the fifth sub-Jupiter-mass (0.2 < m(p)/M-Jup < 1) microlensing planet around an M dwarf with the mass well constrained. The relatively rich harvest of sub-Jupiters around M dwarfs is contrasted with a possible paucity of similar to 1-2 Jupiter-mass planets around the same type of star, which can be explained by the planetary formation process in the core-accretion scheme.</P>