877 results on '"Yoshikazu Tanaka"'
Search Results
2. Lattice-commensurate skyrmion texture in a centrosymmetric breathing kagome magnet
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Max Hirschberger, Bertalan G. Szigeti, Mamoun Hemmida, Moritz M. Hirschmann, Sebastian Esser, Hiroyuki Ohsumi, Yoshikazu Tanaka, Leonie Spitz, Shang Gao, Kamil K. Kolincio, Hajime Sagayama, Hironori Nakao, Yuichi Yamasaki, László Forró, Hans-Albrecht Krug von Nidda, Istvan Kezsmarki, Taka-hisa Arima, and Yoshinori Tokura
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Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Atomic physics. Constitution and properties of matter ,QC170-197 - Abstract
Abstract Skyrmion lattices (SkL) in centrosymmetric materials typically have a magnetic period on the nanometer-scale, so that the coupling between magnetic superstructures and the underlying crystal lattice cannot be neglected. We reveal the commensurate locking of a SkL to the atomic lattice in Gd3Ru4Al12 via high-resolution resonant elastic x-ray scattering (REXS). Weak easy-plane magnetic anisotropy, demonstrated here by a combination of ferromagnetic resonance and REXS, penalizes placing a skyrmion core on a site of the atomic lattice. Under these conditions, a commensurate SkL, locked to the crystal lattice, is stable at finite temperatures – but gives way to a competing incommensurate ground state upon cooling. We discuss the role of Umklapp-terms in the Hamiltonian for the formation of this lattice-locked state, its magnetic space group, and the role of slight discommensurations, or (line) defects in the magnetic texture. We also contrast our findings with the case of SkLs in noncentrosymmetric material platforms.
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- 2024
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3. Changes in plasma metabolite concentrations and enzyme activities in aging riding horses
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Yukari Asahi, Toshiro Arai, and Yoshikazu Tanaka
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adiponectin ,age-related disease ,chronic inflammation ,inflammaging ,serum amyloid A ,Veterinary medicine ,SF600-1100 - Abstract
In older horses, basal metabolic rate decreases, and plasma metabolite and hormone concentrations related to energy metabolism change. The occurrence of age-related diseases, which increases in old animals, may enhance inflammatory reactivity (inflammaging). Finding the appropriate treatment for inflammaging at an early stage may prevent various age-related diseases. Changes in metabolite and hormone concentrations and enzyme activities involved in energy metabolism in the plasma of clinically healthy riding horses of various ages were measured to identify biomarkers of inflammaging (persistent low-grade inflammation that occurs with aging). All horses were clinically healthy, and their body condition scores (BCSs) were 4 or 5 (9-point scale). Plasma triglyceride (TG), total cholesterol (T-Cho), blood urea nitrogen (BUN), insulin concentrations, malondialdehyde (MDA), and serum amyloid A (SAA) concentrations generally increased with age. Adiponectin concentrations, plasma superoxide dismutase (SOD), and leukocyte AMP-activated protein kinase (AMPK) activities decreased, while plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutathione peroxidase (GPx) remained unchanged as horses aged. Although riding horses that partake in continuous exercise seems to be less likely to develop inflammaging, horses over 17 years of age tend to show proinflammatory signs with disordered lipid metabolism. In riding horses, SAA, in combination with other markers, may be a useful biomarker for inflammaging and dysregulated lipid metabolism in aging horses.
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- 2024
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4. Double-Swing Spring Origami Triboelectric Nanogenerators for Self-Powered Ocean Monitoring
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Xinru Du, Hao Zhang, Hao Cao, Zewei Hao, Takuji Nakashima, Yoshikazu Tanaka, Pengcheng Jiao, and Hidemi Mutsuda
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spring origami (SO) structures ,triboelectric nanogenerators (TENGs) ,self-powered ocean monitoring ,wave–device interaction and structural optimization ,smoothed-particle hydrodynamics (SPH) ,Technology - Abstract
Coastal areas often experience high population density and intense human activity owing to the considerable value of the ocean. Therefore, devices for monitoring marine disasters are crucial for ensuring the safety of human life. Herein, we develop hemispherical spring origami (SO) triboelectric nanogenerators (TENGs) (HSO-TENGs) for self-powered ocean wave monitoring. Optimization is performed using two approaches. First, swing machine experiments are conducted to investigate the monitoring performance of the HSO-TENGs regarding wave height and period with satisfactory accuracy. To increase power generation and monitoring accuracy, the internal inertia and centroid of gravity of the HSO-TENGs are optimized with respect to the structural parameters (i.e., magnet weight, hammer height, and external swing arm length). Second, numerical simulations are performed using the smoothed-particle hydrodynamics (SPH) method to determine the most suitable fixed condition for the HSO-TENGs for sensing wave changes. Subsequently, wave tank experiments are conducted on the HSO-TENGs to determine their ability to sense wave height, period, frequency, and direction. Tests related to supplying other sensors are also conducted. Eventually, the ability of the HSO-TENGs to monitor wave direction and spreading parameters is investigated in a numerical SPH circular wave tank. The results prove that the optimized HSO-TENGs can achieve powering and sensing through the same device.
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- 2024
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5. The difference in the cellular uptake of tocopherol and tocotrienol is influenced by their affinities to albumin
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Takashi Nakatomi, Mayuko Itaya-Takahashi, Yosuke Horikoshi, Naoki Shimizu, Isabella Supardi Parida, Mirinthorn Jutanom, Takahiro Eitsuka, Yoshikazu Tanaka, Jean-Marc Zingg, Tatsuya Matsura, and Kiyotaka Nakagawa
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Medicine ,Science - Abstract
Abstract Vitamin E is classified into tocopherol (Toc) and tocotrienol (T3) based on its side chains. T3 generally has higher cellular uptake than Toc, though the responsible mechanism remains unclear. To elucidate this mechanism, we hypothesized and investigated whether serum albumin is a factor that induces such a difference in the cellular uptake of Toc and T3. Adding bovine serum albumin (BSA) to serum-depleted media increased the cellular uptake of T3 and decreased that of Toc, with varying degrees among α-, β-, γ-, and δ-analogs. Such enhanced uptake of α-T3 was not observed when cells were incubated under low temperature (the uptake of α-Toc was also reduced), suggesting that Toc and T3 bind to albumin to form a complex that results in differential cellular uptake of vitamin E. Fluorescence quenching study confirmed that vitamin E certainly bound to BSA, and that T3 showed a higher affinity than Toc. Molecular docking further indicated that the differential binding energy of Toc or T3 to BSA is due to the Van der Waals interactions via their side chain. Overall, these results suggested that the affinity of Toc and T3 to albumin differs due to their side chains, causing the difference in their albumin-mediated cellular uptake. Our results give a better mechanistic insight into the physiological action of vitamin E.
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- 2023
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6. RPL3L-containing ribosomes determine translation elongation dynamics required for cardiac function
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Chisa Shiraishi, Akinobu Matsumoto, Kazuya Ichihara, Taishi Yamamoto, Takeshi Yokoyama, Taisuke Mizoo, Atsushi Hatano, Masaki Matsumoto, Yoshikazu Tanaka, Eriko Matsuura-Suzuki, Shintaro Iwasaki, Shouji Matsushima, Hiroyuki Tsutsui, and Keiichi I. Nakayama
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Science - Abstract
Abstract Although several ribosomal protein paralogs are expressed in a tissue-specific manner, how these proteins affect translation and why they are required only in certain tissues have remained unclear. Here we show that RPL3L, a paralog of RPL3 specifically expressed in heart and skeletal muscle, influences translation elongation dynamics. Deficiency of RPL3L-containing ribosomes in RPL3L knockout male mice resulted in impaired cardiac contractility. Ribosome occupancy at mRNA codons was found to be altered in the RPL3L-deficient heart, and the changes were negatively correlated with those observed in myoblasts overexpressing RPL3L. RPL3L-containing ribosomes were less prone to collisions compared with RPL3-containing canonical ribosomes. Although the loss of RPL3L-containing ribosomes altered translation elongation dynamics for the entire transcriptome, its effects were most pronounced for transcripts related to cardiac muscle contraction and dilated cardiomyopathy, with the abundance of the encoded proteins being correspondingly decreased. Our results provide further insight into the mechanisms and physiological relevance of tissue-specific translational regulation.
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- 2023
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7. A marine sponge-derived lectin reveals hidden pathway for thrombopoietin receptor activation
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Hiromi Watari, Hiromu Kageyama, Nami Masubuchi, Hiroya Nakajima, Kako Onodera, Pamela J. Focia, Takumi Oshiro, Takashi Matsui, Yoshio Kodera, Tomohisa Ogawa, Takeshi Yokoyama, Makoto Hirayama, Kanji Hori, Douglas M. Freymann, Misa Imai, Norio Komatsu, Marito Araki, Yoshikazu Tanaka, and Ryuichi Sakai
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Science - Abstract
The mode of cytokine receptor activation is diverse. Here, the authors find that the marine-sponge derived lectin ThC, a bivalent sugar binding protein, activates human cytokine receptor MPL. This mode of action resembles the pathogenic activation of MPL by mutant molecular chaperon calreticulin in hematologic malignancies.
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- 2022
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8. An ancestral function of strigolactones as symbiotic rhizosphere signals
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Kyoichi Kodama, Mélanie K. Rich, Akiyoshi Yoda, Shota Shimazaki, Xiaonan Xie, Kohki Akiyama, Yohei Mizuno, Aino Komatsu, Yi Luo, Hidemasa Suzuki, Hiromu Kameoka, Cyril Libourel, Jean Keller, Keiko Sakakibara, Tomoaki Nishiyama, Tomomi Nakagawa, Kiyoshi Mashiguchi, Kenichi Uchida, Kaori Yoneyama, Yoshikazu Tanaka, Shinjiro Yamaguchi, Masaki Shimamura, Pierre-Marc Delaux, Takahito Nomura, and Junko Kyozuka
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Science - Abstract
Strigolactones (SLs) regulate angiosperm development and promote symbiosis with arbuscular mycorrhizae. Here the authors show that bryosymbiol, an SL present in bryophytes and angiosperms, promotes AM symbiosis in Marchantia paleacea suggesting an ancestral function of SLs as rhizosphere signals.
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- 2022
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9. Determination of sub-ps lattice dynamics in FeRh thin films
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Michael Grimes, Hiroki Ueda, Dmitry Ozerov, Federico Pressacco, Sergii Parchenko, Andreas Apseros, Markus Scholz, Yuya Kubota, Tadashi Togashi, Yoshikazu Tanaka, Laura Heyderman, Thomas Thomson, and Valerio Scagnoli
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Medicine ,Science - Abstract
Abstract Understanding the ultrashort time scale structural dynamics of the FeRh metamagnetic phase transition is a key element in developing a complete explanation of the mechanism driving the evolution from an antiferromagnetic to ferromagnetic state. Using an X-ray free electron laser we determine, with sub-ps time resolution, the time evolution of the (–101) lattice diffraction peak following excitation using a 35 fs laser pulse. The dynamics at higher laser fluence indicates the existence of a transient lattice state distinct from the high temperature ferromagnetic phase. By extracting the lattice temperature and comparing it with values obtained in a quasi-static diffraction measurement, we estimate the electron–phonon coupling in FeRh thin films as a function of laser excitation fluence. A model is presented which demonstrates that the transient state is paramagnetic and can be reached by a subset of the phonon bands. A complete description of the FeRh structural dynamics requires consideration of coupling strength variation across the phonon frequencies.
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- 2022
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10. Can addition of frozen section analysis to preoperative endometrial biopsy and MRI improve identification of high-risk endometrial cancer patients?
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Go Nakai, Yoshikazu Tanaka, Takashi Yamada, Masahide Ohmichi, Kazuhiro Yamamoto, and Keigo Osuga
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Endometrial cancer ,Frozen section ,MRI ,Preoperative endometrial biopsy ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Surgeons sometimes have difficulty determining which result to favor when preoperative results (MRI + preoperative endometrial biopsy [pre-op EB]) differ from intraoperative frozen section histology (FS) results. Investigation of how FS can complement ordinary preoperative examinations like MRI and pre-op EB in identification of patients at high risk of lymph node metastasis (high-risk patients) could provide clarity on this issue. Therefore, the aim of this study is to assess the utility of pre-op EB, MRI and FS results and determine how to combine these results in identification of high-risk patients. Methods The subjects were 172 patients with endometrial cancer. Patients with a histological high-grade tumor (HGT), namely, grade 3 endometrioid cancer, clear cell carcinoma or serous cell carcinoma, or with any type of cancer invading at least half of the uterine myometrium were considered high-risk. Tumors invading at least half of the uterine myometrium were classified as high-stage tumors (HST). We compared (a) detection of HGT using pre-op EB versus FS, (b) detection of HST using MRI versus FS, and (c) identification of high-risk patients using MRI + pre-op EB versus FS. Lastly, we determined to what degree addition of FS results improves identification of high-risk patients by routine MRI + pre-op EB. Results (a) Sensitivity, specificity, and accuracy for detecting HGT were 59.6, 98.4 and 87.8% for pre-op EB versus 55.3, 99.2 and 87.2% for FS (P = 0.44). (b) These figures for detecting HST were 74.4, 83.0 and 80.8% for MRI versus 46.5, 99.2 and 86.0% for FS (P < 0.001). (c) These figures for identifying high-risk patients were 78.3, 85.4 and 82.6% for MRI + pre-op EB versus 55.1, 99.0 and 81.2% for FS (P < 0.001). The high specificity of FS improved the sensitivity of MRI + pre-op EB from 78.3 to 81.2%, but this difference was not statistically significant (P < 0.16). Conclusion Frozen section enables identification of high-risk patients with nearly 100% specificity. This advantage can be used to improve sensitivity for identification of high-risk patients by routine MRI + pre-op EB, although this improvement is not statistically significant.
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- 2021
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11. Long-term outcomes of transsclerally sutured intraocular lens correctly fixed in the ciliary sulcus
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Tetsuro Oshika, Yasushi Inoue, Tohru Sakimoto, Takeshi Sugiura, and Yoshikazu Tanaka
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Ophthalmology ,RE1-994 - Abstract
Objective To report the long-term postoperative outcomes of transsclerally sutured intraocular lenses (IOLs), in which the haptics were correctly fixated into the ciliary sulcus using an auxiliary device and endoscope.Methods and analysis Data were collected from eyes that were followed up for at least 12 months after ciliary sulcus suture fixation of an IOL using an auxiliary device for securely placing the IOL haptics to the ciliary sulcus, which was confirmed using intraoperative endoscopy in all cases. The corrected distance visual acuity (CDVA), refractive error, anterior chamber depth (ACD), IOL decentration and tilt, corneal endothelial cell density (CECD) and postoperative complications were recorded. ACD and IOL deviations were compared with those of normal controls after standard cataract surgery.Results A total of 146 eyes of 142 patients were included, with a mean follow-up period of 56.0±35.3 (range 12–174) months. Postoperative CDVA from 1 month to 8 years and final CDVA were significantly better, and the mean refraction error, ACD and CECD decline rate were −0.71±0.75 dioptre, 4.01±0.37 mm and −7.4%±16.0%, respectively. Compared with normal controls, ACD was not significantly different but the tilt and decentration were significantly different. The main postoperative complications included vitreous haemorrhage (24.0%), suture thread exposure (19.2%) and corectopia (18.5%). There were no cases of IOL dislocation due to suture breakage or postoperative endophthalmitisConclusion Long-term postoperative outcomes were favorable with good CDVA and without IOL dislocation and endophthalmitis. The significance and value of fixing haptics to the ciliary sulcus should be re-evaluated.
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- 2022
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12. Anti-EGFR antibody 528 binds to domain III of EGFR at a site shifted from the cetuximab epitope
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Koki Makabe, Takeshi Yokoyama, Shiro Uehara, Tomomi Uchikubo-Kamo, Mikako Shirouzu, Kouki Kimura, Kouhei Tsumoto, Ryutaro Asano, Yoshikazu Tanaka, and Izumi Kumagai
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Medicine ,Science - Abstract
Abstract Antibodies have been widely used for cancer therapy owing to their ability to distinguish cancer cells by recognizing cancer-specific antigens. Epidermal growth factor receptor (EGFR) is a promising target for the cancer therapeutics, against which several antibody clones have been developed and brought into therapeutic use. Another antibody clone, 528, is an antagonistic anti-EGFR antibody, which has been the focus of our antibody engineering studies to develop cancer drugs. In this study, we explored the interaction of 528 with the extracellular region of EGFR (sEGFR) via binding analyses and structural studies. Dot blotting experiments with heat treated sEGFR and surface plasmon resonance binding experiments revealed that 528 recognizes the tertiary structure of sEGFR and exhibits competitive binding to sEGFR with EGF and cetuximab. Single particle analysis of the sEGFR–528 Fab complex via electron microscopy clearly showed the binding of 528 to domain III of sEGFR, the domain to which EGF and cetuximab bind, explaining its antagonistic activity. Comparison between the two-dimensional class average and the cetuximab/sEGFR crystal structure revealed that 528 binds to a site that is shifted from, rather than identical to, the cetuximab epitope, and may exclude known drug-resistant EGFR mutations.
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- 2021
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13. Omental herniation through the esophageal hiatus: A rare cause of gastric outlet obstruction and its CT findings
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Yoshikazu Tanaka, MD, PhD, Yoshinori Saika, MD, PhD, Yoshito Asao, MD, Mitsuru Tanaka, MD, and Ryuji Nohara, MD, PhD
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Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
A man in his 60s visited the emergency department because of epigastric pain and vomiting. Noncontrast helical abdominal CT revealed a lipomatous mass on the right side of the lower esophagus. Caudal slices showed that the mass appeared to displace the gastric antrum causing gastric outlet obstruction. Further observation revealed a linear structure from the greater curvature of the stomach into the omental vessels. Based on these findings, a diagnosis of intrathoracic omental hernia through the esophageal hiatus was made. Intraoperatively, a defect in the lesser omentum was seen, and the greater omentum herniated through the defect into the esophageal hiatus. Omental herniation through the lesser omentum into the esophageal hiatus can present as gastric outlet obstruction. Keywords: Omental herniation, Hiatus hernia, Mediastinum, CT
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- 2020
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14. Canine Mammary Tumor Cell Lines Derived from Metastatic Foci Show Increased RAD51 Expression but Diminished Radioresistance via p21 Inhibition
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Kei Shimakawa, Kazuhiko Ochiai, Sachi Hirose, Eri Tanabe, Masaki Michishita, Motoharu Sakaue, Yasunaga Yoshikawa, Masami Morimatsu, Tsuyoshi Tajima, Masami Watanabe, and Yoshikazu Tanaka
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canine ,DNA damage repair ,mammary tumor ,p21 ,RAD51 ,Veterinary medicine ,SF600-1100 - Abstract
Due to the high incidence of mammary tumors in dogs, it is important to elucidate the pathogenesis of these tumors in veterinary medicine. Radiation therapy is often used to treat mammary tumors that target DNA lesions. RAD51 is a key molecule that repairs DNA damage via homologous recombination. We examined the relationship between RAD51 expression and radiosensitivity in mammary tumor cell lines. CHMp and CHMm from the same individual were selected based on the differences in RAD51 expression. The radiosensitivity of both cell lines was examined using MTT and scratch assays; CHMm, which has high RAD51 expression, showed higher sensitivity to radiation than CHMp. However, the nuclear focus of RAD51 during DNA repair was formed normally in CHMp, but not in most of CHMm. Since irradiation resulted in the suppression of cell cycle progression in CHMp, the expression of p21, a cell cycle regulatory factor, was detected in CHMp after 15 Gy irradiation but not in CHMm. These results indicate that functional expression is more important than the quantitative expression of RAD51 in canine mammary tumor cells in response to DNA damage.
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- 2022
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15. Estimation of the reference lead (Pb) concentration levels affecting immune cells in the blood of Black-headed Gulls (Chroicocephalus ridibundus, Laridae)
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Nana Ushine, Osamu Kurata, Yoshikazu Tanaka, Shouta M.M. Nakayama, Mayumi Ishizuka, Takuya Kato, and Shin-Ichi Hayama
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blood pb level ,japan ,long-term bird conservation ,low-level contamination ,Ecology ,QH540-549.5 - Abstract
The biological effects of lead (Pb) contamination have been reported in various species. There are no restrictions on the use of Pb products, including bullets, in the areas south of Hokkaido, Japan. Local governments have announced the presence of Pb in the soil sediments of water bodies. Previous studies have confirmed the relationship between blood Pb level (BLL) and immune cells. This study was performed with the aim of clarifying the effect of Pb contamination on immune cells. In total, 170 Black-headed Gulls (Chroicocephalus ridibundus) were captured, including a population in Tokyo Bay between November 2018 and April 2021 and a population in Mikawa Bay between January 2019 and April 2021. Linear regression analysis was performed with the white blood cell count (WBC), proportion of heterophils (Het), proportion of lymphocytes (Lym), ratio of heterophils and lymphocytes (H/L ratio), copy number of CD4 messenger RNA, and copy number of CD8α messenger RNA as the objective variables, and the BLL as the explanatory variable. The group with BLL < 1.0 µg/dL had a significantly lower Het and higher Lym than that with BLL > 3.5 µg/dL (P < 0.05). In addition, the group with BLL < 1.0 µg/dL had a significantly lower H/L ratio than that with BLL > 3.5 µg/dL. CD8α and WBC were higher in the group with BLL ranging from 1.0 to 3.5 µg/dL than in the group with BLL < 1.0 µg/dL. This study suggests that the effect of Pb pollution on the immune cells of Black-headed Gulls is lower than some previous criteria values. It is possible that gulls affected by Pb contamination suffer indirect negative effects on immune function, possibly making them more susceptible to infectious diseases. Pb is a major environmental pollutant, against which measures must be taken.
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- 2022
16. A case report of ectopic pancreatitis in an isolated enteric duplication cyst
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Yoshikazu Tanaka, Go Nakai, Hideki Tomiyama, Yoshitaka Kurisu, and Yoshifumi Narumi
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Isolated enteric duplication cyst ,Mesenteric Meckel’s diverticulum ,Ectopic pancreas ,Surgery ,RD1-811 - Abstract
Abstract Background Isolated enteric duplication cyst is an intestinal duplication cyst found in a distant location from the intestinal tract and it is said to have its own blood supply. Meckel’s diverticulm is considered as an antimesenteric structure and has its own blood supply. However, there are some reported cases of Meckele’s diverticum in the mesenteric side. Ectopic pancreas may be found in both entities. Case presentation A 5-year-old girl presented with increasing abdominal pain around the umbilicus. On laboratory investigation serum pancreatic enzymes and C-reactive protein were elevated. Abdominal computed tomography (CT) revealed a normal pancreas but a cystic lesion in the mesentery of the ileum. A nodule with a marked enhancement was observed in the wall of the lesion. During the laparoscopy, the lesion was found at the root of the mesentery and was distant from the ileum. The lesion was resected suspecting an abscess. Pathologically, the wall of the lesion consisted of small bowel like tissue, and pancreatic tissue was seen beneath the mucosa. There were some post inflammatory changes in the pancreatic tissue. Retrospectively on thin slice enhanced CT, an independent blood supply was noted. Based on these findings, a diagnosis of ectopic pancreatitis in an iliac intestinal duplication cyst was made. Conclusion Isolated enteric duplication cyst in the root of ileal mesentery and mesenteric Meckel’s diverticulum have similarities. In the present case, the diagnosis of isolated enteric duplication cyst was made since it was found distant from the ileum. It is important to consider the possibility of ectopic pancreatitis when serum pancreatic enzymes are elevated even when the pancreas appears normal.
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- 2019
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17. Cryo-EM reveals the asymmetric assembly of squid hemocyanin
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Yoshikazu Tanaka, Sanae Kato, Markus Stabrin, Stefan Raunser, Takashi Matsui, and Christos Gatsogiannis
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single-particle cryo-EM ,structure determination ,cryo-electron microscopy ,macromolecular machines ,protein structures ,Crystallography ,QD901-999 - Abstract
The oxygen transporter of molluscs, hemocyanin, consists of long pearl-necklace-like subunits of several globular domains. The subunits assemble in a complex manner to form cylindrical decamers. Typically, the first six domains of each subunit assemble together to form the cylinder wall, while the C-terminal domains form a collar that fills or caps the cylinder. During evolution, various molluscs have been able to fine-tune their oxygen binding by deleting or adding C-terminal domains and adjusting their inner-collar architecture. However, squids have duplicated one of the wall domains of their subunits instead. Here, using cryo-EM and an optimized refinement protocol implemented in SPHIRE, this work tackled the symmetry-mismatched structure of squid hemocyanin, revealing the precise effect of this duplication on its quaternary structure and providing a potential model for its structural evolution.
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- 2019
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18. A case of torsion of a normal ovary in the third trimester of pregnancy: MRI findings with emphasis on asymmetry in the diameter of the ovarian veins
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Yoshikazu Tanaka, MD, Takahiro Tsuboyama, MD, PhD, Kazuhiro Yamamoto, MD, PhD, Yoshito Terai, MD, PhD, Masahide Ohmichi, MD, PhD, and Yoshifumi Narumi, MD, PhD
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Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
A 33-year-old woman, gravida two para one, at 31 weeks of gestational age experienced sudden onset of left lower quadrant pain and underwent unenhanced pelvic MRI. On fast imaging employing steady state precession (FIESTA) sequence images, a marked difference was observed in the diameters of the right and left ovarian veins. The right ovarian vein was torturous and dilated, measuring 35 mm in diameter, while the left ovarian vein was thin and linear, measuring 7 mm in diameter. The left ovary showed no apparent swelling or hemorrhage, but was suspected to have been shifted anteriorly. The patient underwent explorative laparotomy and was found to have left ovarian torsion. A difference in diameter of the ovarian veins, with thinning of the twisted side and compensatory dilatation of the contralateral side for drainage of increased uterine blood flow, may be a useful imaging sign for the diagnosis of ovarian torsion during pregnancy. Keywords: Ovarian torsion, Third trimester in pregnancy, MRI
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- 2019
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19. Ionophore Antibiotics Inhibit Type II Feline Coronavirus Proliferation In Vitro
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Yoshikazu Tanaka, Eri Tanabe, Yuki Nonaka, Mitsuki Uemura, Tsuyoshi Tajima, and Kazuhiko Ochiai
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feline coronavirus ,ionophore antibiotics ,feline infectious peritonitis ,nigericin ,valinomycin ,salinomycin ,Microbiology ,QR1-502 - Abstract
Feline coronaviruses (FCoVs) infect cats worldwide and cause severe systemic diseases, such as feline infectious peritonitis (FIP). FIP has a high mortality rate, and drugs approved by the Food and Drug Administration have been ineffective for the treatment of FIP. Investigating host factors and the functions required for FCoV replication is necessary to develop effective drugs for the treatment of FIP. FCoV utilizes an endosomal trafficking system for cellular entry after binding between the viral spike (S) protein and its receptor. The cellular enzymes that cleave the S protein of FCoV to release the viral genome into the cytosol require an acidic pH optimized in the endosomes by regulating cellular ion concentrations. Ionophore antibiotics are compounds that form complexes with alkali ions to alter the endosomal pH conditions. This study shows that ionophore antibiotics, including valinomycin, salinomycin, and nigericin, inhibit FCoV proliferation in vitro in a dose-dependent manner. These results suggest that ionophore antibiotics should be investigated further as potential broad-spectrum anti-FCoV agents.
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- 2022
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20. A rare case of corneal keloid occurred 30 years after pterygium surgery and 3 years after cataract surgery
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Reina Miyamoto, Tohru Sakimoto, Taku Homma, Yoshikazu Tanaka, Takeshi Sugiura, and Satoru Yamagami
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Corneal keloid ,Superficial keratectomy ,Pterygium surgery ,Ophthalmology ,RE1-994 - Abstract
Purpose: We report a case of corneal keloid occurring 30 years after pterygium surgery and 3 years after cataract surgery. Observations: The case of a 72-year-old man was referred because of blurred vision and corneal opacity in the right eye. Pterygium surgery had been performed on the right eye 30 years earlier, and bilateral cataract surgery had been done uneventfully via a temporal corneal incision 3 years ago. Deterioration of vision occurred in the right eye from 2 years ago. At the initial visit, his best corrected visual acuity (BCVA) was 20/2000 on the right. A white nodule that was well demarcated from the underlying stroma was seen on the right cornea. The nodule was excised by superficial keratectomy, with BCVA being 180/200 at 1 week after surgery. Pathological examination of the resected specimen revealed proliferation of fibroblasts and haphazard arrangement of collagen bundles, leading to a diagnosis of corneal keloid. Keloid-like lesion was also later noted in temporal corneal incision site of cataract surgery. Conclusions and importance: This rare case of corneal keloid occurred as a late complication of pterygium surgery.
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- 2020
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21. Optical excitation of electromagnons in hexaferrite
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Hiroki Ueda, Hoyoung Jang, Sae Hwan Chun, Hyeong-Do Kim, Minseok Kim, Sang-Youn Park, Simone Finizio, Nazaret Ortiz Hernandez, Vladimir Ovuka, Matteo Savoini, Tsuyoshi Kimura, Yoshikazu Tanaka, Andrin Doll, and Urs Staub
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Physics ,QC1-999 - Abstract
Understanding ultrafast magnetization dynamics on the microscopic level is of strong current interest due to the potential for applications in information storage. In recent years, spin-lattice coupling has been recognized as essential for ultrafast magnetization dynamics. Magnetoelectric multiferroics of type II possess intrinsic correlations among magnetic sublattices and electric polarization (P) through spin-lattice coupling, enabling fundamentally coupled dynamics between spins and lattice. Here, we report on ultrafast magnetization dynamics in a room-temperature multiferroic hexaferrite possessing ferrimagnetic (FM) and antiferromagnetic sublattices, revealed by time-resolved resonant x-ray diffraction. A femtosecond above-bandgap excitation triggers a coherent magnon in which the two magnetic sublattices entangle and give rise to a transient modulation of P. A microscopic mechanism for triggering the coherent magnon in this FM insulator based on the spin-lattice coupling is proposed. Our finding opens a general pathway for ultrafast control of magnetism.
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- 2022
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22. Rewriting the phase diagram of a diamagnetic liquid crystal by a magnetic field
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Fatin Hajjaj, Takashi Kajitani, Hiroyuki Ohsumi, Yoshikazu Tanaka, Kenichi Kato, Masaki Takata, Hideaki Kitazawa, Taka-hisa Arima, Takuzo Aida, and Takanori Fukushima
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Science - Abstract
Magnetically induced phase behaviour in a soft matter system is of potential interest for magneto-responsive compounds. Here the authors fabricate a discotic ionic liquid crystalline hybrid material which can be switched from orthorhombic to cubic phase in the absence or presence of a strong magnetic field.
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- 2018
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23. Structural basis for tRNA-dependent cysteine biosynthesis
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Meirong Chen, Koji Kato, Yume Kubo, Yoshikazu Tanaka, Yuchen Liu, Feng Long, William B. Whitman, Pascal Lill, Christos Gatsogiannis, Stefan Raunser, Nobutaka Shimizu, Akira Shinoda, Akiyoshi Nakamura, Isao Tanaka, and Min Yao
- Subjects
Science - Abstract
tRNA-dependent cysteine biosynthesis is catalyzed by the transsulfursome protein complex. Here, the authors use a multidisciplinary approach to structurally characterize the archaeal transsulfursome and propose a model for tRNA channeling in the complex.
- Published
- 2017
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24. Structural involvement in the melting of the charge density wave in 1T-TiSe_{2}
- Author
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Max Burian, Michael Porer, Jose R. L. Mardegan, Vincent Esposito, Sergii Parchenko, Bulat Burganov, Namrata Gurung, Mahesh Ramakrishnan, Valerio Scagnoli, Hiroki Ueda, Sonia Francoual, Federica Fabrizi, Yoshikazu Tanaka, Tadashi Togashi, Yuya Kubota, Makina Yabashi, Kai Rossnagel, Steven L. Johnson, and Urs Staub
- Subjects
Physics ,QC1-999 - Abstract
In this work, we use ultrafast pump-probe nonresonant and resonant x-ray diffraction to track the periodic lattice distortion and the electronic charge density wave in 1T-TiSe_{2} upon optical excitation. We observe a fluence regime in which the periodic lattice deformation is strongly suppressed but the charge density wave related Se 4p orbital order remains mostly intact. Complete melting of both structural and electronic order occurs four to five times faster than expected from a purely electronic charge-screening process, strongly suggesting a structurally assisted weakening of excitonic correlations. Our experimental data provide insight on the intricate coupling between structural and electronic order in stabilizing the periodic-lattice-distortion/charge-density-wave state in 1T-TiSe_{2}. The results further show that electron-phonon coupling can lead to different, energy dependent phase-transition pathways in condensed matter systems, opening different possibilities in the conception of nonequilibrium phenomena at the ultrafast scale.
- Published
- 2021
- Full Text
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25. Genome sequence and analysis of the Japanese morning glory Ipomoea nil
- Author
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Atsushi Hoshino, Vasanthan Jayakumar, Eiji Nitasaka, Atsushi Toyoda, Hideki Noguchi, Takehiko Itoh, Tadasu Shin-I, Yohei Minakuchi, Yuki Koda, Atsushi J. Nagano, Masaki Yasugi, Mie N. Honjo, Hiroshi Kudoh, Motoaki Seki, Asako Kamiya, Toshiyuki Shiraki, Piero Carninci, Erika Asamizu, Hiroyo Nishide, Sachiko Tanaka, Kyeung-Il Park, Yasumasa Morita, Kohei Yokoyama, Ikuo Uchiyama, Yoshikazu Tanaka, Satoshi Tabata, Kazuo Shinozaki, Yoshihide Hayashizaki, Yuji Kohara, Yutaka Suzuki, Sumio Sugano, Asao Fujiyama, Shigeru Iida, and Yasubumi Sakakibara
- Subjects
Science - Abstract
Japanese morning glory (Ipomoea nil) has diverse flowering traits. Here, the authors describe the reference genome sequence of I. nil, annotations of genes and transposons, and compare evolution of the I. nilgenome to other Convolvulaceae and Solanales genomes.
- Published
- 2016
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26. Dynamics of the photoinduced insulator-to-metal transition in a nickelate film
- Author
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Vincent Esposito, Laurenz Rettig, Elisabeth M. Bothschafter, Yunpei Deng, Christian Dornes, Lucas Huber, Tim Huber, Gerhard Ingold, Yuichi Inubushi, Tetsuo Katayama, Tomoya Kawaguchi, Henrik Lemke, Kanade Ogawa, Shigeki Owada, Milan Radovic, Mahesh Ramakrishnan, Zoran Ristic, Valerio Scagnoli, Yoshikazu Tanaka, Tadashi Togashi, Kensuke Tono, Ivan Usov, Yoav W. Windsor, Makina Yabashi, Steven L. Johnson, Paul Beaud, and Urs Staub
- Subjects
Crystallography ,QD901-999 - Abstract
Material properties can be controlled via strain, pressure, chemical composition, or dimensionality. Nickelates are particularly susceptible due to their strong variations of the electronic and magnetic properties on such external stimuli. Here, we analyze the photoinduced dynamics in a single crystalline NdNiO3 film upon excitation across the electronic gap. Using time-resolved reflectivity and resonant x-ray diffraction, we show that the pump pulse induces an insulator-to-metal transition, accompanied by the melting of the charge order. Finally, we compare our results with similar studies in manganites and show that the same model can be used to describe the dynamics in nickelates, hinting towards a unified description of these photoinduced electronic ordering phase transitions.
- Published
- 2018
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27. Kinetics of a Phonon-Mediated Laser-Driven Structural Phase Transition in Sn2P2Se6
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Martin Kubli, Matteo Savoini, Elsa Abreu, Bulat Burganov, Gabriel Lantz, Lucas Huber, Martin J. Neugebauer, Larissa Boie, Vincent Esposito, Elisabeth M. Bothschafter, Sergii Parchenko, Sebastian Grübel, Michael Porer, Jochen Rittmann, Paul Beaud, Urs Staub, Makina Yabashi, Yoshikazu Tanaka, Tetsuo Katayama, Tadashi Togashi, Anton A. Kohutych, Yulian M. Vysochanskii, and Steven L. Johnson
- Subjects
structural dynamics ,time-resolved diffraction ,ferroelectricity ,incommensurate structure ,phase transition ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
We investigate the structural dynamics of the incommensurately modulated phase of Sn 2 P 2 Se 6 by means of time-resolved X-ray diffraction following excitation by an optical pump. Tracking the incommensurable distortion in the time domain enables us to identify the transport effects leading to a complete disappearance of the incommensurate phase over the course of 100 ns. These observations suggest that a thin surface layer of the high-temperature phase forms quickly after photo-excitation and then propagates into the material with a constant velocity of 3.7 m/s. Complementary static structural measurements reveal previously unreported higher-order satellite reflection in the incommensurate phase. These higher-order reflections are attributed to cubic vibrational terms in the Hamiltonian.
- Published
- 2019
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28. Suppression of Coronavirus Replication by Cyclophilin Inhibitors
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Takashi Sasaki, Yoshikazu Tanaka, and Yuka Sato
- Subjects
cyclophilin ,cyclosporin A ,coronavirus ,NF-AT ,Microbiology ,QR1-502 - Abstract
Coronaviruses infect a variety of mammalian and avian species and cause serious diseases in humans, cats, mice, and birds in the form of severe acute respiratory syndrome (SARS), feline infectious peritonitis (FIP), mouse hepatitis, and avian infectious bronchitis, respectively. No effective vaccine or treatment has been developed for SARS-coronavirus or FIP virus, both of which cause lethal diseases. It has been reported that a cyclophilin inhibitor, cyclosporin A (CsA), could inhibit the replication of coronaviruses. CsA is a well-known immunosuppressive drug that binds to cellular cyclophilins to inhibit calcineurin, a calcium-calmodulin-activated serine/threonine-specific phosphatase. The inhibition of calcineurin blocks the translocation of nuclear factor of activated T cells from the cytosol into the nucleus, thus preventing the transcription of genes encoding cytokines such as interleukin-2. Cyclophilins are peptidyl-prolyl isomerases with physiological functions that have been described for many years to include chaperone and foldase activities. Also, many viruses require cyclophilins for replication; these include human immunodeficiency virus, vesicular stomatitis virus, and hepatitis C virus. However, the molecular mechanisms leading to the suppression of viral replication differ for different viruses. This review describes the suppressive effects of CsA on coronavirus replication.
- Published
- 2013
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29. Development of a real-time imaging system for hypoxic cell apoptosis
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Go Kagiya, Ryohei Ogawa, Fuminori Hyodo, Kei Yamashita, Mizuki Nakamura, Ayumi Ishii, Yukihiko Sejimo, Shintaro Tominaga, Masaharu Murata, Yoshikazu Tanaka, and Masanori Hatashita
- Subjects
Genetics ,QH426-470 ,Cytology ,QH573-671 - Abstract
Hypoxic regions within the tumor form due to imbalances between cell proliferation and angiogenesis; specifically, temporary closure or a reduced flow due to abnormal vasculature. They create environments where cancer cells acquire resistance to therapies. Therefore, the development of therapeutic approaches targeting the hypoxic cells is one of the most crucial challenges for cancer regression. Screening potential candidates for effective diagnostic modalities even under a hypoxic environment would be an important first step. In this study, we describe the development of a real-time imaging system to monitor hypoxic cell apoptosis for such screening. The imaging system is composed of a cyclic luciferase (luc) gene under the control of an improved hypoxic-responsive promoter. The cyclic luc gene product works as a caspase-3 (cas-3) monitor as it gains luc activity in response to cas-3 activation. The promoter composed of six hypoxic responsible elements and the CMV IE1 core promoter drives the effective expression of the cyclic luc gene in hypoxic conditions, enhancing hypoxic cell apoptosis visualization. We also confirmed real-time imaging of hypoxic cell apoptosis in the spheroid, which shares properties with the tumor. Thus, this constructed system could be a powerful tool for the development of effective anticancer diagnostic modalities.
- Published
- 2016
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30. The Effect of Sandblasting of UHMWPE Substrate on the Wear Resistance of Hydrogen-Containing Carbon Coating
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Yoshinori Takeichi, Takafumi Higashiyama, Takahiro Nakahigashi, Yoshikazu Tanaka, Masanori Tsujioka, and Masao Uemura
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hydrogen-containing carbon coating ,uhmwpe ,adhesion ,surface asperity ,sandblasting ,sodium hydrogen carbonate abrasive ,Physics ,QC1-999 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Mechanical engineering and machinery ,TJ1-1570 ,Chemistry ,QD1-999 - Abstract
Surface asperities were made on the surface of UHMWPE by sandblasting with sodium hydrogen carbonate abrasive in order to enhance the adhesion of hydrogen-containing carbon (HCC) coating to substrate. Sodium hydrogen carbonate abrasive was used because it easily solutes in hot water and the blasted abrasive stuck into the surface of UHMWPE can be entirely removed by washing with hot water. The HCC coating was deposited on the polished UHMWPE substrate and blasted substrate by RF-plasma CVD method. Friction test was conducted with the ball-on-disk tribometer in the distilled water. As the results of SEM observation and Raman spectroscopy analysis of the friction track on the HCC coating, it was confirmed that a substantial quantity of HCC coating deposited on the blasted substrate was remained on the friction track as compared with the polished substrate. It is concluded that the appropriate blasting treatment of UHMWPE substrate enhances the adhesiveness of the HCC coating to the substrate and improves wear resistance of HCC coating.
- Published
- 2008
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31. Flexible sensor for the impact force measurement in flexible interface
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Chen LIU, Yukio FUJIMOTO, Yoshikazu TANAKA, Tadashi UESUGI, and Takahiro NAMIKAWA
- Subjects
flexible sensor ,impact force ,boxing ,punch ,flexible interface ,soft material ,distribution type sensor ,Mechanical engineering and machinery ,TJ1-1570 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
When human body is punched by the boxing glove, both of the body surface and the boxing glove deform in a complex shape. The purpose of this study is to develop a flexible sensor that can be used in such interface. Firstly, several mechanical phenomena, which are the cause of error signal of the sensor, are discussed. These are the influences of out-of-plane bending deformation, shear force caused by rubbing force, shear force caused by the Poisson's effect of contact material, and the transverse compressive force caused by the overhanging deformation of flexible material. Then as a sensor that can eliminate the error factors of these, a distribution type impact sensor in which sixteen sensor elements are arranged in a 4x4 matrix is developed. Punching experiments using a boxing glove are carried out by installing the sensor on the load cell, on the concrete wall and on the sandbag. From the experiment, it is found that the impact force can be measured with good accuracy by using the sensor. Despite the sensor has inadequate distribution number of sensor elements, the sensor structure includes mechanical requirements for the flexible impact sensor.
- Published
- 2014
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32. Suppressive effects of irbesartan on inflammation and apoptosis in atherosclerotic plaques of apoE-/- mice: molecular imaging with 14C-FDG and 99mTc-annexin A5.
- Author
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Yan Zhao, Ayahisa Watanabe, Songji Zhao, Tatsuo Kobayashi, Keita Fukao, Yoshikazu Tanaka, Toru Nakano, Tetsuya Yoshida, Hiroshi Takemoto, Nagara Tamaki, and Yuji Kuge
- Subjects
Medicine ,Science - Abstract
To investigate the effects of irbesartan on inflammation and apoptosis in atherosclerotic plaques by histochemical examination and molecular imaging using (14)C-FDG and (99m)Tc-annexin A5.Irbesartan has a peroxisome proliferator-activated receptor gamma (PPARγ) activation property in addition to its ability to block the AT1 receptor. Accordingly, irbesartan may exert further anti-inflammatory and anti-apoptotic effects in atherosclerotic plaques. However, such effects of irbesartan have not been fully investigated. Molecular imaging using (18)F-FDG and (99m)Tc-annexin A5 is useful for evaluating inflammation and apoptosis in atherosclerotic plaques.Female apoE(-/-) mice were treated with irbesartan-mixed (50 mg/kg/day) or irbesartan-free (control) diet for 12 weeks (n = 11/group). One week after the treatment, the mice were co-injected with (14)C-FDG and (99m)Tc-annexin A5, and cryostat sections of the aortic root were prepared. Histochemical examination with Movat's pentachrome (plaque size), Oil Red O (lipid deposition), Mac-2 (macrophage infiltration), and TUNEL (apoptosis) stainings were performed. Dual-tracer autoradiography was carried out to evaluate the levels of (14)C-FDG and (99m)Tc-annexin A5 in plaques (%ID×kg). In vitro experiments were performed to investigate the mechanism underlying the effects.Histological examination indicated that irbesartan treatment significantly reduced plaque size (to 56.4%±11.1% of control), intra-plaque lipid deposition (53.6%±20.2%) and macrophage infiltration (61.9%±20.8%) levels, and the number of apoptotic cells (14.5%±16.6%). (14)C-FDG (43.0%±18.6%) and (99m)Tc-annexin A5 levels (45.9%±16.8%) were also significantly reduced by irbesartan treatment. Irbesartan significantly suppressed MCP-1 mRNA expression in TNF-α stimulated THP-1 monocytes (64.8%±8.4% of un-treated cells). PPARγ activation was observed in cells treated with irbesartan (134%±36% at 3 µM to 3329%±218% at 81 µM) by a PPARγ reporter assay system.Remissions of inflammation and apoptosis as potential therapeutic effects of irbesartan on atherosclerosis were observed. The usefulness of molecular imaging using (18)F-FDG and (99m)Tc-annexin A5 for evaluating the therapeutic effects of irbesartan on atherosclerosis was also suggested.
- Published
- 2014
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33. The effect of a novel, small non-peptidyl molecule butyzamide on human thrombopoietin receptor and megakaryopoiesis
- Author
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Wataru Nogami, Hiroshi Yoshida, Kenzo Koizumi, Hajime Yamada, Kenji Abe, Akinori Arimura, Noriko Yamane, Koji Takahashi, Akiko Yamane, Atsushi Oda, Yoshikazu Tanaka, Hiroshi Takemoto, Yasuyuki Ohnishi, Yasuo Ikeda, and Yoshitaka Miyakawa
- Subjects
Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Background Thrombocytopenia is a common problem in the management of patients with cancer and other conditions that affect hematopoietic cells. In previous clinical trials, the polyethylene-glycol-conjugated recombinant human megakaryocyte growth and development factor increased platelet counts in patients with idiopathic thrombocytopenic purpura and solid tumors undergoing chemotherapy. However, antibodies to polyethylene-glycol-conjugated recombinant human megakaryocyte growth and development factor develop in healthy volunteers and patients undergoing chemotherapy and cross-react with endogenous thrombopoietin. As a result, clinical development of polyethylene-glycol-conjugated recombinant human megakaryocyte growth and development factor was discontinued in 1998. The aim of this study was to identify an orally bioavailable human Mpl activator that does not develop autoantibodies against endogenous thrombopoietin.Design and Methods We screened our chemical library and created a novel non-peptidyl thrombopoietin receptor, Mpl activator named butyzamide. We evaluated the effect of butyzamide on megakaryopoiesis in vitro using Ba/F3 cells expressing Mpl and human hematopoietic stem cells. For the evaluation of its in vivo effect, we administered butyzamide orally to immunodeficient NOD/Shi-scid,IL-2Rγnull (NOG) mice transplanted with human fetal liver-derived CD34+ cells and investigated the production of human platelets.Results Butyzamide specifically reacted with human Mpl and activated the same signal transduction pathway as thrombopoietin. However, unlike thrombopoietin, butyzamide did not react with murine Mpl and was shown to require the histidine residue in the transmembrane domain of Mpl for its agonistic activity. Butyzamide induced colony-forming unit-megakaryocytes and polyploid megakaryocytes from human CD34+ hematopoietic progenitor cells, and its effects were comparable to those of thrombopoietin. When butyzamide was administered orally at the doses of 10 and 50 mg/kg for 20 days to NOG mice transplanted with human fetal liver-derived CD34+ cells, the human platelet count increased by 6.2- and 22.9-fold, respectively.Conclusions Butyzamide is an orally bioavailable human Mpl activator, and appears to have potential for clinical development as a therapeutic agent for patients with thrombocytopenia.
- Published
- 2008
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34. Design of cyborg proteins by loop region replacement with oligo(ethylene glycol): exploring suitable mutations for cyborg protein construction using machine learning.
- Author
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Wijak Yospanya, Akari Matsumura, Yukihiro Imasato, Tomoyuki Itou, Yusuke Aoki, Hikaru Nakazawa, Takashi Matsui, Takeshi Yokoyama, Mihoko Ui, Mitsuo Umetsu, Satoru Nagatoishi, Kouhei Tsumoto, Yoshikazu Tanaka, and Kazushi Kinbara
- Subjects
ETHYLENE glycol ,MACHINE learning ,OLIGOMERS ,GREEN fluorescent protein ,THROMBIN - Abstract
We synthesized a "cyborg protein," wherein a synthetic molecule partially substitutes the main peptide chain by linking 2 protein domains with a synthetic oligomer. Green fluorescent protein (GFP) served as the model for constructing the cyborg proteins. We prepared circularly permuted GFP (cpGFP) with new termini between β10 and β11, where the original N- and C-termini were linked by a cleavable peptide loop. The cyborg GFP was constructed from cpGFP by linking the β10 and β11 with oligo(ethylene glycol) (OEG) using maleimide-cysteine couplings, followed by the enzymatic cleavage of the N- and C-termini linking loop by thrombin. With the help of machine learning, we were able to obtain the cpGFP mutants that significantly alter the fluorescence intensity (53% increase) by thrombin treatment, which splits cpGFP into 2 fragments (fragmented GFP), and by heat shock. When the cyborg GFP was constructed using this mutant, the fluorescence intensity increased by 13% after heat treatment, similar to cpGFP (33% increase), and the behavior was significantly different from that of the fragmented GFP. This result suggests the possibility that the OEG chain in the cyborg protein plays a similar role to the peptide in the main chain of the protein. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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35. Activities of Japanese party in McMurdo Sound area 1976-1977
- Author
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Katsutada Kaminuma, Tetsuya Torii, Keizo Yanai, Genki Matsumoto, and Yoshikazu TANAKA
- Subjects
Geography (General) ,G1-922 - Published
- 1977
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36. Startospheric Electric Fields and Currents Measured at Syowa Station, Antarctica
- Author
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Yoshikazu TANAKA, Toshio OGAWA, and Masahiro KODAMA
- Subjects
Geography (General) ,G1-922 - Abstract
The measurements of vector electric fields and currents were made with two plastic balloons of 5,000 m^3 launched from Syowa Station (L=8.4), Antarctica, on 28 November and 29 December, 1972. The results give the following. (1) The vertical electric field and current at the altitude of 30km are 0.12-0.21 V/m and 1.3-2.2 x10^ A/m^2 respectively, and their diurnal variations are roughly consistent with the expected variation from the average world-wide thunderstorm activity. (2) The electrical conductivities were estimated from the ratio of the electric current to the electric field giving the average value of 1 x 10^ mho/m at the altitude of 30 km. This value is about twice as large as that in Japan. This can be explained by the latitudinal effect of the cosmic ray ionization in the atmosphere. (3) Enhancements of the electric field and current were observed in both vertical and horizontal components of the magnitude of about 80 mV/m and 0.8 x 10^ A/m^2 respectively at an initial stage of a magnetic substorm. The vertical electric field on the ground was also correspondingly enhanced by about 80 V/m at the same time. (4) Comparisons of observed horizontal electric field vectors with the magnetic fields observed at Syowa Station show that the magnetic field variations are caused by the ionospheric Hall current. (5) One hour averages of the horizontal electric field show large scale convection fields consistent with S^p_q in the polar ionosphere and with DP-2 in the equatorial magnetosphere. The average ionospheric and magnetospheric equatorial electric fields were 40 mV/m and 0.98 mV/m respectively, and corresponding plasma convection velocities were estimated to be 700 m/s and 22 km/s respectively.
- Published
- 1975
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37. High-power low-modulating-voltage 1.5 μm-band CWDM Uncooled EMLs for 800 Gb/s (53.125 Gbaud-PAM4) Transceivers.
- Author
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Shinya Okuda, Takeshi Yamatoya, Tsutomu Yamaguchi, Yusuke Azuma, and Yoshikazu Tanaka
- Published
- 2021
38. Simple Method for the Creation of a Bacteria-Sized Unilamellar Liposome with Different Proteins Localized to the Respective Sides of the Membrane
- Author
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Kosaku Noba, Shogo Yoshimoto, Yoshikazu Tanaka, Takeshi Yokoyama, Tomoaki Matsuura, and Katsutoshi Hori
- Subjects
Biomedical Engineering ,General Medicine ,Biochemistry, Genetics and Molecular Biology (miscellaneous) - Published
- 2023
39. Numerical calculation method of magnetization and eddy current by applying the subdomain method to integral equations
- Author
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Yoshikazu Tanaka and Kazuki Simojyo
- Subjects
Mechanics of Materials ,Mechanical Engineering ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials - Abstract
The magnetic targeting method is expected for the regeneration of cartilage of knee. Magnetically labeled mesenchymal stem cells (m-MSCs) and an external magnetic field are used in the magnetic targeting method. A numerical calculation method for simulating the behavior of the m-MSC is needed. In this paper a numerical calculation method of magnetization and eddy current by applying the subdomain method to integral equations is presented. The proposed method has been used to solve two problems for which the exact solutions are known, namely the magnetization of a sphere placed in a uniform magnetic field and the eddy current induced in a flat plate, to verify its validity. Through the two problems, the validity of the proposed method has been confirmed.
- Published
- 2023
40. Detection of anti-feline infectious peritonitis virus activity of a Chinese herb extract using geneLEAD VIII, a fully automated nucleic acid extraction/quantitative PCR testing system
- Author
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Rui NISHIJIMA, Takuro ENDO, Enkhjavkhlan GANKHUYAG, Shwe Thiri Maung Maung KHIN, Sheikhy Mohammad JAFAR, Yuta SHINOHARA, Yoshikazu TANAKA, Kazumi SAWAKAMI, Masafumi YOHDA, and Tetsuya FURUYA
- Subjects
General Veterinary - Published
- 2023
41. Experimental and numerical studies on working parameter selections of a piezoelectric-painted-based ocean energy harvester attached to fish aggregating devices
- Author
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Xinru Du, Hidemi Mutsuda, Yoshikazu Tanaka, Takuji Nakashima, Taiga Kanehira, Naokazu Taniguchi, and Yasuo Moriyama
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Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,Management, Monitoring, Policy and Law - Published
- 2022
42. Developing Design Support System Based on Semantic of Design Model.
- Author
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Yoshikazu Tanaka and Kazuhiko Tsuda
- Published
- 2016
- Full Text
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43. Model-Driven Development of Water Hammer Analysis Software for Irrigation Pipeline System.
- Author
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Yoshikazu Tanaka and Kazuhiko Tsuda
- Published
- 2016
- Full Text
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44. Functional Characterization of 12 Dihydropyrimidinase Allelic Variants in Japanese Individuals for the Prediction of 5-Fluorouracil Treatment-Related Toxicity
- Author
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Eiji Hishinuma, Yoko Narita, Evelyn Marie Gutiérrez Rico, Akiko Ueda, Kai Obuchi, Yoshikazu Tanaka, Sakae Saito, Shu Tadaka, Kengo Kinoshita, Masamitsu Maekawa, Nariyasu Mano, Tomoki Nakayoshi, Akifumi Oda, Noriyasu Hirasawa, and Masahiro Hiratsuka
- Subjects
Pharmacology ,Pharmaceutical Science - Published
- 2022
45. Dose-response relationship for the resistance of human insulin to degradation by insulin-degrading enzyme
- Author
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Masaki Okumura, Tsubura Kuramochi, Yuxi Lin, Ran Furukawa, Kenji Mizutani, Takeshi Yokoyama, Mingeun Kim, Mi Hee Lim, Hyon-Seung Yi, Kenta Arai, Hiroshi Yamaguchi, Hironobu Hojo, Michio Iwaoka, Yoshikazu Tanaka, Sam-Yong Park, Kenji Inaba, Shingo Kanemura, and Young-Ho Lee
- Abstract
SUMMARYDeeper understanding of the mechanism of the action of insulin and insulin-degrading enzyme (IDE) is a central theme in research into physiology and the pathophysiology of type 2 diabetes mellitus. Despite significant progress regarding the substrate recruitment, unfolding, digestion, and release by IDE, the structure and function of the insulin hexamer during the degradation cycle of IDE remain to be fully characterized. In the present study, we have characterized the behavior of human insulin hexamer in the absence of zinc. Using cryo-electron microscopy, we also observed that these hexamers represented a structure similar to that of T6insulin. More interestingly, we also observed complexes in which some of their monomeric insulin components are partially distorted at their hexametric symmetry. This ensures that insulin determines the kinetics of its degradation by IDE without the requirement for zinc. These findings provide new information regarding the molecular events in insulin assembly and disassembly that permit its selective digestion by IDE.
- Published
- 2023
46. Numerical and experimental studies on specimens with integrated pulse-shaper used for the instrumented Taylor impact test to measure stress-strain curves at high rates of strain
- Author
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Chong Gao, Takeshi Iwamoto, Yoshikazu Tanaka, and Takayuki Kusaka
- Subjects
Mechanics of Materials ,Mechanical Engineering ,Automotive Engineering ,Aerospace Engineering ,Ocean Engineering ,Safety, Risk, Reliability and Quality ,Civil and Structural Engineering - Published
- 2023
47. Feasibility Study of Visualizing Strain Distributions Using Opal Film
- Author
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Yoshikazu Tanaka, Hiroshi Fudouzi, and Tsuyoshi Hyakutake
- Subjects
Materials science ,Strain (chemistry) ,Mechanics of Materials ,Mechanical Engineering ,Materials Chemistry ,Metals and Alloys ,Strain mapping ,Structural health monitoring ,Composite material - Published
- 2022
48. Structural and molecular insight into antibody recognition of dynamic neoepitope in membrane tethered MUC1 of pancreatic cancer cells and secreted exosomes
- Author
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Shin-Ichiro Nishimura, Hajime Wakui, Yasuhiro Yokoi, Chieko Horidome, Toyoyuki Ose, Min Yao, Yoshikazu Tanaka, and Hiroshi Hinou
- Subjects
Chemistry (miscellaneous) ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Molecular Biology ,Biochemistry - Abstract
Pancreatic cancer is highly metastatic and poor prognosis, mainly due to delayed detection, often after metastasis has occurred. Advent of a novel method to enable early detection and disease intervention...
- Published
- 2023
49. Performance of turbo frequency domain equalizer using iterative decision-directed channel estimation for DFT-precoded OFDMA.
- Author
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Chihiro Mori, Yoshikazu Tanaka, Teruo Kawamura, Nobuhiko Miki, and Mamoru Sawahashi
- Published
- 2013
50. Can addition of frozen section analysis to preoperative endometrial biopsy and MRI improve identification of high-risk endometrial cancer patients?
- Author
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Keigo Osuga, Go Nakai, Masahide Ohmichi, Yoshikazu Tanaka, Kazuhiro Yamamoto, and Takashi Yamada
- Subjects
Adult ,Cancer Research ,Frozen section ,Biopsy ,Risk Assessment ,Sensitivity and Specificity ,Endometrium ,Endometrial cancer ,Predictive Value of Tests ,Preoperative Care ,Genetics ,Carcinoma ,medicine ,Frozen Sections ,Humans ,Neoplasm Invasiveness ,RC254-282 ,Aged ,Aged, 80 and over ,Frozen section procedure ,medicine.diagnostic_test ,business.industry ,Research ,Myometrium ,Cancer ,Preoperative endometrial biopsy ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Histology ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Cystadenocarcinoma, Serous ,Endometrial Neoplasms ,Oncology ,Lymphatic Metastasis ,Clear cell carcinoma ,Lymph Node Excision ,Female ,Neoplasm Grading ,Nuclear medicine ,business ,Endometrial biopsy ,Adenocarcinoma, Clear Cell ,MRI - Abstract
Background Surgeons sometimes have difficulty determining which result to favor when preoperative results (MRI + preoperative endometrial biopsy [pre-op EB]) differ from intraoperative frozen section histology (FS) results. Investigation of how FS can complement ordinary preoperative examinations like MRI and pre-op EB in identification of patients at high risk of lymph node metastasis (high-risk patients) could provide clarity on this issue. Therefore, the aim of this study is to assess the utility of pre-op EB, MRI and FS results and determine how to combine these results in identification of high-risk patients. Methods The subjects were 172 patients with endometrial cancer. Patients with a histological high-grade tumor (HGT), namely, grade 3 endometrioid cancer, clear cell carcinoma or serous cell carcinoma, or with any type of cancer invading at least half of the uterine myometrium were considered high-risk. Tumors invading at least half of the uterine myometrium were classified as high-stage tumors (HST). We compared (a) detection of HGT using pre-op EB versus FS, (b) detection of HST using MRI versus FS, and (c) identification of high-risk patients using MRI + pre-op EB versus FS. Lastly, we determined to what degree addition of FS results improves identification of high-risk patients by routine MRI + pre-op EB. Results (a) Sensitivity, specificity, and accuracy for detecting HGT were 59.6, 98.4 and 87.8% for pre-op EB versus 55.3, 99.2 and 87.2% for FS (P = 0.44). (b) These figures for detecting HST were 74.4, 83.0 and 80.8% for MRI versus 46.5, 99.2 and 86.0% for FS (P < 0.001). (c) These figures for identifying high-risk patients were 78.3, 85.4 and 82.6% for MRI + pre-op EB versus 55.1, 99.0 and 81.2% for FS (P < 0.001). The high specificity of FS improved the sensitivity of MRI + pre-op EB from 78.3 to 81.2%, but this difference was not statistically significant (P < 0.16). Conclusion Frozen section enables identification of high-risk patients with nearly 100% specificity. This advantage can be used to improve sensitivity for identification of high-risk patients by routine MRI + pre-op EB, although this improvement is not statistically significant.
- Published
- 2021
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