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91.
Kana Kobayashi-Taguchi Takashi Saitou Yoshiaki Kamei Akari Murakami Kanako Nishiyama Reina Aoki Erina Kusakabe Haruna Noda Michiko Yamashita Riko Kitazawa Takeshi Imamura Yasutsugu Takada 《Molecules (Basel, Switzerland)》2022,27(10)
Fibroadenomas (FAs) and phyllodes tumors (PTs) are major benign breast tumors, pathologically classified as fibroepithelial tumors. Although the clinical management of PTs differs from FAs, distinction by core needle biopsy diagnoses is still challenging. Here, a combined technique of label-free imaging with multi-photon microscopy and artificial intelligence was applied to detect quantitative signatures that differentiate fibroepithelial lesions. Multi-photon excited autofluorescence and second harmonic generation (SHG) signals were detected in tissue sections. A pixel-wise semantic segmentation method using a deep learning framework was used to separate epithelial and stromal regions automatically. The epithelial to stromal area ratio and the collagen SHG signal strength were investigated for their ability to distinguish fibroepithelial lesions. An image segmentation analysis with a pixel-wise semantic segmentation framework using a deep convolutional neural network showed the accurate separation of epithelial and stromal regions. A further investigation, to determine if scoring the epithelial to stromal area ratio and the SHG signal strength within the stromal area could be a marker for differentiating fibroepithelial tumors, showed accurate classification. Therefore, molecular and morphological changes, detected through the assistance of computational and label-free multi-photon imaging techniques, enable us to propose quantitative signatures for epithelial and stromal alterations in breast tissues. 相似文献
92.
93.
Keiichiro Shiraga Yuichi Ogawa Shojiro Kikuchi Masayuki Amagai Takeshi Matsui 《Molecules (Basel, Switzerland)》2022,27(9)
While bulk water and hydration water coexist in cells to support the expression of biological macromolecules, how the dynamics of water molecules, which have long been only a minor role in molecular biology research, relate to changes in cellular states such as cell death has hardly been explored so far due to the lack of evaluation techniques. In this study, we developed a high-precision measurement system that can discriminate bulk water content changes of ±0.02% (0.2 mg/cm3) with single-cell-level spatial resolution based on a near-field CMOS dielectric sensor operating at 65 GHz. We applied this system to evaluate the temporal changes in the bulk water content during the cell death process of keratinocytes, called corneoptosis, using isolated SG1 (first layer of stratum granulosum) cells in vitro. A significant irreversible increase in the bulk water content was observed approximately 1 h before membrane disruption during corneoptosis, which starts with cytoplasmic high Ca2+ signal. These findings suggest that the calcium flux may have a role in triggering the increase in the bulk water content in SG1 cells. Thus, our near-field CMOS dielectric sensor provides a valuable tool to dissect the involvement of water molecules in the various events that occur in the cell. 相似文献
94.
Takeshi Nishii Fumiaki Miyamae Makoto Yoshizuka Hiroto Kaku Mitsuyo Horikawa Makoto Inai Tetsuto Tsunoda 《Tetrahedron: Asymmetry》2012,23(10):739-741
Excess lithium hexamethyldisilazide (LHMDS) with LiCl prompted the asymmetric aza-Claisen rearrangement of carboxamide and retarded the decomposition of its amide enolate. The addition of these two reagents was a key step that led to the total synthesis of (+)-α-cuparenone with a stereogenic quaternary center. 相似文献
95.
Takehito Dei Kazuhide Morino Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2012,50(13):2619-2625
Novel copolymers composed of a styrene (St) derivative bearing a vicinal tricarbonyl moiety and various vinyl monomers such as St, methyl methacrylate (MMA), and N‐vinylpyrrolidone (NVP) were synthesized by (1) radical copolymerization of a St derivative with a 1,3‐diketone structure with St, MMA, and NVP and (2) successive oxidation of the resulting copolymers with N‐bromosuccinimide in DMSO to convert their 1,3‐diketone moieties in the side chains into the corresponding vicinal tricarbonyl moieties. Their tricarbonyl moieties were readily hydrated in water‐containing acetone to generate the corresponding copolymers bearing geminal diol structures in the side chains. On the other hand, heating the resulting copolymers bearing the geminal diol structures in vacuo‐enabled successful recovery of the vicinal tricarbonyl moieties to demonstrate the reversible nature of this system. The hydration behavior in powdery state under air atmosphere saturated by water was also investigated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
96.
Dr. Ding‐Bang Xiong Dr. Norihiko L. Okamoto Dr. Takeshi Waki Dr. Yufeng Zhao Dr. Kyosuke Kishida Prof. Dr. Haruyuki Inui 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(9):2536-2542
Heusler phases, including the full‐ and half‐Heusler families, represent an outstanding class of multifunctional materials on account of their great tunability in compositions, valence electron counts (VEC), and properties. Here we demonstrate a systematic design of a series of new compounds with a 2×2×2 superstructure of the half‐Heusler unit cell in X–Y–Z (X=Fe, Ru, Co, Rh, Ir; Y=Zn, Mn; Z=Sn, Sb) systems. Their structures were solved by using both powder and single‐crystal X‐ray diffraction, and also directly observed by using high‐angle annular dark‐field imaging in a scanning transmission electron microscope (HAADF‐STEM). The VEC values of these new compounds span a wide and continuous range comparable to those for the full‐ and half‐Heusler families, thereby implying tunability in compositions and physical properties in the superstructure. In fact, we observed abnormal electrical properties and a ferromagnetic semiconductor‐like behavior with a high and tunable Curie temperature in these superstructures. 相似文献
97.
Takeshi Eitoku Kazuya Taniguchi Yuta Nakazato Shunichi Ono Kenji Katayama 《Optical Review》2010,17(1):5-9
Formation process of gold nanoparticles was investigated by near-field heterodyne transient grating method. In the absence
of the protective agents, although the diffusion of H[AuICl2] could be observed after the photo-reduction of H[AuIIICl4], the diffusion of nanoparticle-seeds was not observed. On the other hand, in the presence of the protective agents, the
diffusion of a complex molecule (Au and protective agent) and nanoparticle-seeds could be observed. From these results, it
was found that enough amount of the complex is essential for the nanoparticle formation. We also investigated the formation
process with four different chemicals as a protective agent. The hydrodynamic radius of nanoparticle-seeds generated in the
poly(vinyl pyrrolidone) and TritonX-100 solutions were larger than those generated in the Tween 20 and Brij 58 solutions.
The former two have hydrophilic chain in the molecular structure; on the other hand, the latter two have hydrophobic alkyl
chain. Based on those facts, we concluded that the interaction between the chains of the complex molecule plays an important
role in the nanoparticle formation process. 相似文献
98.
Makoto Okawara Takeshi Endo Eisuke Fujiwara Takayoshi Hirose 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):441-459
Polymers containing 1,4-dihydronicotinamide (P-NAH) alloxan (P-A), and viologen (P-V2+) moieties were synthesized and characterized. P-NAH reduced various organic substances such as lipoic acid, alloxan, and viologens and also immobilized quinone mediated by alloxan. P-A was reduced to the polymer-bearing alloxan radical and the dialuric acid structure without crosslinks by one- and two-electron reduction, respectively, and P-A also mediated the redox reaction occurring between aqueous and organic (water-immiscible) layers. P-V2+ was converted to the stable viologen radical reversibly by one-electron reduction. Electric potentials and currents on photo-reduction of P-V2+ and catalytic behavior of P-V2+ in the reduction of carbonyl compounds were examined. 相似文献
99.
Hiroyuki Nishide Naoki Yoshioka Yukoh Saitoh Ritsuko Gotoh Takeshi Miyakawa Eishun Tsuchida 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(9):775-786
Abstract m- and p Bis(diphenylene)propenylphenylacetylene (m-, p-8) were synthesized and polymerized with WCI6, MoCl5, and Rh catalyst, yielding solvent-soluble poly(phenylacetylene)s bearing a π-conjugated bis(di-phenylene)propenyl groups (m-, p-7a). The polymers gave their polyanion derivatives, which were electrolytically and chemically oxidized to yield the corresponding polyradicals (m-, p-7b). The polyradicals were chemically very stable due to the resonance stabilization of an unpaired electron whose spin concentration could be increased up to ca. 2 × 1023 spins per molar monomer unit. ESR spectroscopy suggested an antiferro-magnetic interaction between unpaired electrons. 相似文献