38 results on '"Shuhei Aoyama"'
Search Results
2. Suppression of androgen receptor signaling induces prostate cancer migration via activation of the <scp>CCL20</scp> – <scp>CCR6</scp> axis
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Hiroshi Kano, Kouji Izumi, Kaoru Hiratsuka, Ren Toriumi, Ryunosuke Nakagawa, Shuhei Aoyama, Taiki Kamijima, Takafumi Shimada, Renato Naito, Suguru Kadomoto, Hiroaki Iwamoto, Hiroshi Yaegashi, Shohei Kawaguchi, Takahiro Nohara, Kazuyoshi Shigehara, Yoshifumi Kadono, Yohei Saito, Kyoko Nakagawa‐Goto, Kazuaki Yoshioka, Hiroki Nakata, Wen‐Jye Lin, and Atsushi Mizokami more...
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Cancer Research ,Oncology ,General Medicine - Abstract
The suppression of androgen receptor (AR) expression exacerbates the migration potential of prostate cancer. This study identified a previously unrecognized regulation of the AR-controlled pathway that promotes migration potential in prostate cancer cells. Prostate cancer cells that pass through a transwell membrane (mig cells) have a higher migration potential with a decreased AR expression than parental cells. In this study, we aimed to elucidate the mechanism of migration enhancement associated with the suppression of AR signaling. Expression of C-C motif ligand 20 (CCL20) is upregulated in mig cells, unlike in the parental cells. Knockdown of AR with small interfering RNA (siAR) in LNCaP and C4-2B cells increased CCL20 secretion and enhanced the migration of cancer cells. Mig cells, CCL20-treated cells, and siAR cells promoted cell migration with an enhancement of AKT phosphorylation and Snail expression, while the addition of a C-C chemokine receptor 6 (CCR6, the specific receptor of CCL20) inhibitor, anti-CCL20 antibody, and AKT inhibitor suppressed the activation of AKT and Snail. With 59 samples of prostate cancer tissue, CCL20 secretion was profuse in metastatic cases despite low AR expression levels. Snail expression was associated with the expression of CCL20 and CCR6. A xenograft study showed that the anti-CCL20 antibody significantly inhibited Snail expression, thereby suggesting a new therapeutic approach for castration-resistant prostate cancer with the inhibition of the axis between CCL20 and CCR6. more...
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- 2022
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Catalog
3. Genetic ablation of p62/SQSTM1 demonstrates little effect on pancreatic β-cell function under autophagy deficiency
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Toshinaru Fukae, Takeshi Miyatsuka, Miwa Himuro, Yuka Wakabayashi, Hitoshi Iida, Shuhei Aoyama, Tomoya Mita, Fuki Ikeda, Hidenori Haruna, Noriyuki Takubo, Yuya Nishida, Toshiaki Shimizu, and Hirotaka Watada more...
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Mice ,Insulin-Secreting Cells ,Insulin Secretion ,Sequestosome-1 Protein ,Autophagy ,Biophysics ,Animals ,Cell Biology ,Autophagy-Related Protein 7 ,Molecular Biology ,Biochemistry - Abstract
Autophagy is known to play an essential role in intracellular quality control through the degradation of damaged organelles and components. We previously demonstrated that β-cell-specific autophagy deficient mice, which lack Atg7, exhibited impaired glucose tolerance, accompanied by the accumulation of sequestosome 1/p62 (hereafter referred to as p62). Whereas p62 has been reported to play essential roles in regulating cellular homeostasis in the liver and adipose tissue, we previously showed that β-cell-specific p62 deficiency does not cause any apparent impairment in glucose metabolism. In the present study, we investigated the roles of p62 in β cells under autophagy-deficient conditions, by simultaneously inactivating both Atg7 and p62 in a β-cell specific manner. Whereas p62 accumulation was substantially reduced in the islets of Atg7 and p62 double-deficient mice, glucose tolerance and insulin secretion were comparable to Atg7 single-deficient mice. Taken together, these findings suggest that the p62 accumulation appears to have little effect on β-cell function under conditions of autophagy inhibition. more...
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- 2022
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4. Analysis of Pattern Formation by Colored Petri Nets With Quantitative Regulation of Gene Expression Level
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Hiroshi Matsuno, Yumiko Harada, Ryutaro Murakami, Shuhei Aoyama, Fei Liu, Katsunobu Shirahama, Tsubasa Saitoh, and Ena Yamamoto
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Regulation of gene expression ,Computer science ,Applied Mathematics ,Systems biology ,Notch signaling pathway ,Pattern formation ,Petri net ,Models, Biological ,Modeling and simulation ,Multicellular organism ,Gene Expression Regulation ,Genetics ,Animals ,Drosophila Proteins ,Computer Simulation ,Drosophila ,Biological system ,Signal Transduction ,Biotechnology ,Boundary cell - Abstract
Modeling and simulation are becoming indispensable tools for studying multicellular events such as pattern formation during embryonic development. In this paper, we propose a new approach for analyzing multicellular biological phenomena by combining colored hybrid Petri nets (ColHPNs) with newly devised biological experiments that can control level of a gene quantitatively. With this approach, we analyzed patterning of the boundary cells in the Drosophila large intestine, where one-cell-wide domain of boundary cells differentiate through Delta-Notch signaling. Biological experiments regulating the level of Delta resulted in six distinct patterns of boundary cells correlating with the level of Delta. All these patterns were successfully reproduced by simulation based on ColHPN modeling only by changing the parameter related to the level of Delta. By monitoring the concentration of the active form of Notch in each cell during simulation, it was revealed that these distinct modes of patterning correlate with the fluctuation range of active Notch. Combination of simulation and quantitative manipulation of a gene activity described here is a reliable and powerful approach for analyzing and understanding the patterning process regulated by Notch signaling. This approach can be easily adapted to address other similar pattern formation issues in the systems biology area. more...
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- 2022
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5. Monitoring autophagic flux in vivo revealed its physiological response and significance of heterogeneity in pancreatic beta cells
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Shuhei Aoyama, Yuya Nishida, Hirotsugu Uzawa, Miwa Himuro, Akiko Kanai, Kyosei Ueki, Minami Ito, Hitoshi Iida, Isei Tanida, Takeshi Miyatsuka, Yoshio Fujitani, Masaki Matsumoto, and Hirotaka Watada
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Pharmacology ,Clinical Biochemistry ,Drug Discovery ,Molecular Medicine ,Molecular Biology ,Biochemistry - Published
- 2023
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6. Role of positive biopsy core ratio in prostate cancer patients
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Hiroshi Kano, Kouji Izumi, Ryunosuke Nakagawa, Ren Toriumi, Shuhei Aoyama, Taiki Kamijima, Takafumi Shimada, Renato Naito, Suguru Kadomoto, Hiroaki Iwamoto, Hiroshi Yaegashi, Shohei Kawaguchi, Takahiro Nohara, Kazuyoshi Shigehara, Yoshifumi Kadono, and Atsushi Mizokami more...
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Background: The percentage of positive cores (PPC) is increasingly recognized as a prognostic factor in prostate cancer. However, the usefulness of PPC for patients undergoing androgen deprivation therapy (ADT) and high-risk group has not been adequately studied. Methods: A retrospective analysis was conducted of 255 patients who underwent prostate biopsy (all-case group). We examined the efficacy of PPC as a prognostic biomarker. Results: Eighty-nine patients were treated with ADT alone (ADT group), and 107 patients were classified as high-risk (high-risk group). The median duration of follow-up was 112.4 months, 85.3 months, and 110.0 months for the all-case group, ADT group, and high-risk group, respectively. Patients with PPC >60% had significantly shorter prostate cancer-specific survival (CSS) and castration-resistant prostate cancer-free survival (CFS) in the all-case group and ADT group. In high-risk group, patients with PPC >60% had shorter CFS but no difference in CSS. Multivariate analysis showed that significant independent predictors of prostate CSS were the presence of metastasis at diagnosis and PPC >60% in the all-case group and ADT group. Conclusions: This study demonstrates that PPC may be a prognostic factor in ADT treatment and high-risk patients. more...
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- 2023
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7. Serum CCL2 Is a Prognostic Biomarker for Non-Metastatic Castration-Sensitive Prostate Cancer
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Hiroaki Iwamoto, Kouji Izumi, Ryunosuke Nakagawa, Ren Toriumi, Shuhei Aoyama, Taiki Kamijima, Takafumi Shimada, Hiroshi Kano, Tomoyuki Makino, Renato Naito, Suguru Kadomoto, Hiroshi Yaegashi, Shohei Kawaguchi, Takahiro Nohara, Kazuyoshi Shigehara, Yoshifumi Kadono, and Atsushi Mizokami more...
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CCL2 ,biomarker ,prostate cancer ,survival ,prognostic ,chemokine ,Medicine (miscellaneous) ,General Biochemistry, Genetics and Molecular Biology - Abstract
Purpose: Prostate-specific antigen (PSA) is a useful prostate cancer (PC) biomarker, but some cases reported that PSA does not correlate with the Gleason score. Serum chemokine (CC motif) ligand 2 (CCL2) has been reported to be a potential complementary PSA biomarker, but it remains unclear whether it can be applied to non-metastatic castration-sensitive prostate cancer (nmCSPC) or each section of the stages. Serum CCL2′s usefulness was investigated as a prognostic nmCSPC biomarker in this study. Methods: Serum samples were collected from 379 patients who underwent prostate biopsy at Kanazawa University Hospital from 2007 to 2013. A total of 230 patients with nmCSPC were included in this study of the 255 patients with histologically diagnosed prostate cancer. The serum CCL2 efficacy as a prognostic nmCSPC biomarker was investigated retrospectively. Results: An independent significant predictor of worse OS was CCL2 ≥ 280 pg/dL and CRP ≥ 0.5 mg/dL in multivariate analysis. Gleason score ≥ 8 and CCL2 ≥ 280 pg/dL were independent significant predictors of CRPC-free survival (CFS) worsening in multivariate analysis. Serum CCL2 was a predictive biomarker for OS and CFS in nmCSPC. Furthermore, CCL2 ≥ 280 pg/mL patients had significantly worse visceral metastasis-free survival than those with CCL2 < 280 pg/mL. Conclusion: This study is the first to demonstrate serum CCL2 utility as a biomarker to predict OS and CFS in nmCSPC. more...
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- 2022
8. Blood Cell Count Biomarkers Predicting Efficacy of Pembrolizumab as Second-line Therapy for Advanced Urothelial Carcinoma
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Chikashi Seto, Taiki Kamijima, Akinobu Takano, Satoshi Yotsuyanagi, Shuhei Aoyama, Rie Fukuda, Hideki Asahi, Kazuyoshi Shigehara, Yoshifumi Kadono, Ryunosuke Nakagawa, Takahiro Nohara, Atsushi Mizokami, Tohru Miyagi, Kouji Izumi, and Shohei Kawaguchi more...
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Male ,Urologic Neoplasms ,Cancer Research ,medicine.medical_specialty ,Neutrophils ,Pembrolizumab ,Antibodies, Monoclonal, Humanized ,Systemic inflammation ,Gastroenterology ,Blood cell ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Biomarkers, Tumor ,medicine ,Humans ,Peripheral blood cell ,Lymphocytes ,Blood markers ,Aged ,Proportional Hazards Models ,Retrospective Studies ,Urothelial carcinoma ,Aged, 80 and over ,Carcinoma, Transitional Cell ,Second-line therapy ,Proportional hazards model ,business.industry ,fungi ,General Medicine ,Middle Aged ,Blood Cell Count ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Female ,Urothelium ,medicine.symptom ,business - Abstract
BACKGROUND/AIM To investigate the blood markers for predicting pembrolizumab efficacy in advanced urothelial carcinoma (UC). PATIENTS AND METHODS This study included 91 advanced UC patients. The relationship between prognosis and markers from peripheral blood cell counts, including the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), and systemic inflammation response index (SIRI=monocytes × neutrophils/lymphocytes), was evaluated. RESULTS Multivariate analysis indicated that pretreatment NLR and the 1-month-change NLR were both significantly associated with overall survival (OS) after pembrolizumab initiation. When the patients were divided into four groups according to calculated cutoffs using Cox proportional hazard model, the pretreatment NLR more...
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- 2021
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9. Usefulness of serum CCL2 as prognostic biomarker in prostate cancer: a long-term follow-up study
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Hiroaki Iwamoto, Kouji Izumi, Ryunosuke Nakagawa, Ren Toriumi, Shuhei Aoyama, Takafumi Shimada, Hiroshi Kano, Tomoyuki Makino, Suguru Kadomoto, Hiroshi Yaegashi, Shohei Kawaguchi, Takahiro Nohara, Kazuyoshi Shigehara, Yoshifumi Kadono, and Atsushi Mizokami more...
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Male ,Cancer Research ,Prostate ,Prostatic Neoplasms ,General Medicine ,Prostate-Specific Antigen ,Prognosis ,Oncology ,Humans ,Radiology, Nuclear Medicine and imaging ,Biomarkers ,Chemokine CCL2 ,Follow-Up Studies ,Retrospective Studies - Abstract
Objective Prostate-specific antigen is considered the most useful biomarker for prostate cancer, but not in all cases. In a previous study, we have shown that a risk classification combining prostate-specific antigen ≥100 ng/mL and chemokine (CC motif) ligand 2 ≥ 320 pg/mL can predict survivals. We investigated the long-term usefulness of serum chemokine (CC motif) ligand 2 as a complementary biomarker to prostate-specific antigen and developed a novel risk classification system. Methods Serum samples were collected from 379 patients who underwent prostate biopsy at Kanazawa University Hospital between 2007 and 2013, and 255 patients with histologically diagnosed prostate cancer were included in this study. We retrospectively examined the efficacy of serum chemokine (CC motif) ligand 2 as a prognostic biomarker. Results Patients with chemokine (CC motif) ligand 2 ≥ 320 pg/mL exhibited a significantly shorter overall survival, prostate cancer-specific survival and castration-resistant prostate cancer-free survival than those with chemokine (CC motif) ligand 2 Conclusions This study demonstrated the utility of serum chemokine (CC motif) ligand 2 level as a predictive biomarker of long-term overall survival in prostate cancer. A novel risk classification system that predicts long-term overall survival based on the combined indications of chemokine (CC motif) ligand 2 level, prostate-specific antigen level and Gleason score may be a useful prognostic tool for prostate cancer. more...
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- 2022
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10. A 15-Year-Old Boy With Fever and Gait Disturbance
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Shuhei Aoyama, Takuma Ohnishi, Satoshi Sato, Yoji Uejima, and Eisuke Suganuma
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Pediatrics, Perinatology and Child Health - Published
- 2023
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11. Monitoring Autophagic Flux in vivo Revealed Its Physiological Response and Significance of Heterogeneity in Pancreatic Beta Cells
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Shuhei Aoyama, Yuya Nishida, Hirotsugu Uzawa, Miwa Himuro, Akiko Kanai, Kyosei Ueki, Minami Ito, Hitoshi Ida, Isei Tanida, Takeshi Miyatsuka, Yoshio Fujitani, Masaki Matsumoto, and Hirotaka Watada
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- 2022
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12. Favorable Response of Pembrolizumab as Second-Line Therapy for Advanced Urothelial Carcinoma with Only Small Lesions to not be Considered Measurable by RECIST
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Yoshifumi, Kadono, Shohei, Kawaguchi, Takahiro, Nohara, Kazuyoshi, Shigehara, Kouji, Izumi, Taiki, Kamijima, Chikashi, Seto, Akinobu, Takano, Satoshi, Yotsuyanagi, Ryunosuke, Nakagawa, Tohru, Miyagi, Shuhei, Aoyama, Hideki, Asahi, Rie, Fukuda, and Atsushi, Mizokami more...
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Carcinoma, Transitional Cell ,Urinary Bladder Neoplasms ,Humans ,Antibodies, Monoclonal, Humanized ,Response Evaluation Criteria in Solid Tumors ,Aged - Abstract
Pembrolizumab is currently considered the standard second-line treatment for advanced urothelial carcinoma (UC). This study aimed to investigate the efficacy and safety of pembrolizumab in patients with advanced UC in real-world data, which is not well-reported.The study included 97 patients with advanced UC whose lesions were classified according to the Response Evaluation Criteria in Solid Tumors (RECIST). The median age was 73 years. Nineteen patients (20%) with performance status (PS) 2-4 were included. The percentages of liver, lung, bone, and lymph node metastasis were 18%, 27%, 19%, and 76%, respectively. The efficacy, safety, and risk factors for prognosis were evaluated for patients with and without measurable lesions.The best response was complete response in nine patients (9%) and partial response in 16 patients (17%). The median progression-free survival and overall survival were 3.7 months (95% confidence interval [CI]: 2.8-4.7) and 11.8 months (95% CI: 6.7-17.0), respectively. Twenty-one (22%) patients had no measurable lesions per RECIST. In univariate and multivariate analysis, PS 2-4 and lesions by RECIST were identified as factors associated with short overall survival (OS). The median OS of 18.3 months in patients without lesions by RECIST was significantly longer than the median OS of 6.7 months in patients with lesions by RECIST (p = .012).We demonstrated that good PS 0-1 and no measurable lesions, especially small lesions, by RECIST were favorable prognostic factors in patients with advanced UC treated by pembrolizumab. more...
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- 2021
13. Rubicon in pancreatic beta cells plays a limited role in maintaining glucose homeostasis following increased insulin resistance
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Ayako Fukunaka, Tamotsu Yoshimori, Hirotaka Watada, Shuhei Aoyama, Yuya Nishida, Takeshi Miyatsuka, Luka Suzuki, Yoshio Fujitani, and Miwa Himuro
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Blood Glucose ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Carbohydrate metabolism ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,Cell Line, Tumor ,Insulin-Secreting Cells ,Internal medicine ,Autophagy ,medicine ,Animals ,Homeostasis ,Glucose homeostasis ,PI3K/AKT/mTOR pathway ,Mice, Knockout ,Gene knockdown ,biology ,Intracellular Signaling Peptides and Proteins ,medicine.disease ,Insulin receptor ,Gene Knockdown Techniques ,030220 oncology & carcinogenesis ,biology.protein ,Insulin Resistance - Abstract
Autophagy has been reported to play a crucial role in the maintenance of intracellular homeostasis, including in pancreatic beta cells. Rubicon, which interacts with the phosphoinositide 3-kinase (PI3K) complex, through autophagy-related 14 (ATG14), is among the few autophagy regulators that have been reported to inhibit autophagic flux to date and the deletion of Rubicon has been shown to increase autophagic flux. Based on previous results showing a causal relationship between autophagic dysfunction and pancreatic beta-cell impairment, we hypothesized that the deletion of Rubicon in pancreatic beta cells would improve cell integrity and confer protective effects. To test this hypothesis, we first confirmed that Rubicon knockdown (KD) promoted autophagic flux in βTC3 pancreatic beta-cell line. Next, we generated pancreatic beta-cell-specific Rubicon knockout (βKO) mice, by administering tamoxifen to Rubiconflox/flox:MIP-Cre-ERT mice, which showed normal glucose tolerance and insulin secretion under a normal chow diet, despite successful gene recombination. We also attempted to increase insulin resistance by feeding the mice with a high-fat diet for an additional 2 months to find little differences among the parameters evaluated for glucose metabolism. Finally, severe insulin resistance was induced with insulin receptor antagonist treatment, which resulted in comparable glucose homeostasis measurements between Rubicon βKO and control mice. In summary, these results suggest that in pancreatic beta cells, Rubicon plays a limited role in the maintenance of systemic glucose homeostasis. more...
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- 2020
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14. Effects of Iterative Reconstruction on Image Quality of Pediatric Body Computed Tomography Images
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Noriko Kotoura, Rina Muraoka, Yoko Ikeuchi, Shinya Nakano, Masato Kiriki, Katsuhiko Maeda, and Shuhei Aoyama
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Materials science ,Noise power spectrum ,medicine.diagnostic_test ,Phantoms, Imaging ,Image quality ,Data Collection ,Hybrid iterative reconstruction ,Computed tomography ,General Medicine ,Iterative reconstruction ,Radiation Dosage ,Optical transfer function ,medicine ,Humans ,Performance function ,Spatial frequency ,Child ,Tomography, X-Ray Computed ,Algorithms ,Biomedical engineering - Abstract
This study evaluated the effects of three types of hybrid iterative reconstruction (IR) on image quality of pediatric body computed tomography images. The image quality components evaluated were noise power spectrum (NPS), task-based modulation transfer function (TTF), and system performance function (SPF). As the IR strength was increased while reducing the radiation dose, the NPS increased in a low-frequency range and the TTF decreased in low-contrast regions. In the low-contrast regions, the calculated SPF decreased over the entire frequency range. Alternatively, in the high-contrast regions, the SPF decreased in the low-frequency regions and increased in the high-frequency regions. The radiation dose reduction using the hybrid IR resulted in the deterioration of the image quality in the low-contrast regions and changes in the spatial frequency characteristics in the high-contrast regions. more...
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- 2020
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15. Enhanced Immunoadsorption on Imprinted Polymeric Microstructures with Nanoengineered Surface Topography for Lateral Flow Immunoassay Systems
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Shuhei Aoyama, Yuto Akiyama, Minoru Seki, Masumi Yamada, and Kenji Monden
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Immunoassay ,Disease detection ,Polymers ,Surface Properties ,Chemistry ,010401 analytical chemistry ,Nanotechnology ,010402 general chemistry ,Microstructure ,01 natural sciences ,humanities ,Nanostructures ,0104 chemical sciences ,Analytical Chemistry ,C-Reactive Protein ,Solid substrate ,Limit of Detection ,Biological Assay ,Nanotopography ,Adsorption ,Immunoadsorption ,Lateral flow immunoassay - Abstract
Lateral flow immunoassay devices have revolutionized the style of on-site disease detection and point-of-care testing in the past few decades. The surface nanotopography of a solid substrate is a dominant parameter in the efficiency of antibody immobilization, but precise control over surface roughness has not been fully investigated. Here we presented lateral flow immunoassay platforms with nanometer-scale surface roughness, reproducibly engineered using thermal nanoimprinting lithography, and investigated the effects of surface nanotopography on immunoadsorption and immunoassay performance. We fabricated three types of imprinted polycarbonate sheets with microcone array structures having different degrees of surface roughness using three types of molds fabricated by micromachining or laser ablation. The structures fabricated by laser-ablated nickel mold exhibited numerous bumps measuring several tens of nanometers, which enhanced antibody adsorption. We performed sandwich immunoassays of C-reactive protein in serum samples and achieved highly sensitive detection with a detection limit of ∼0.01 μg mL more...
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- 2019
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16. Establishment of a system for screening autophagic flux regulators using a modified fluorescent reporter and CRISPR/Cas9
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Miwa Himuro, Luka Suzuki, Yuya Nishida, Takeshi Miyatsuka, Rieko Yazawa, Toshiaki Shimizu, Hidenori Haruna, Shuhei Aoyama, Hirotaka Watada, Isei Tanida, and Noriyuki Takubo
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0301 basic medicine ,Green Fluorescent Proteins ,Biophysics ,Protein degradation ,Autophagy-Related Protein 7 ,Biochemistry ,Green fluorescent protein ,03 medical and health sciences ,0302 clinical medicine ,Lysosome ,Autophagy ,medicine ,Animals ,Humans ,CRISPR ,Molecular Biology ,Cells, Cultured ,PI3K/AKT/mTOR pathway ,Mice, Knockout ,Chemistry ,Cell Biology ,Fibroblasts ,Embryo, Mammalian ,Cell biology ,Luminescent Proteins ,HEK293 Cells ,030104 developmental biology ,medicine.anatomical_structure ,Gene Expression Regulation ,Microscopy, Fluorescence ,030220 oncology & carcinogenesis ,CRISPR-Cas Systems ,mCherry ,Microtubule-Associated Proteins ,Flux (metabolism) - Abstract
Autophagy is a mechanism of bulk protein degradation that plays an important role in regulating homeostasis in many organisms. Among several methods for evaluating its activity, a fluorescent reporter GFP-LC3-RFP-LC3ΔG, in which GFP-LC3 is cleaved by ATG4 following autophagic induction and degraded in lysosome, has been used for monitoring autophagic flux, which is the amount of lysosomal protein degradation. In this study, we modified this reporter by exchanging GFP for pHluorin, which is more sensitive to low pH, and RFP to mCherry, to construct pHluorin-LC3-mCherry reporter. Following starvation or mTOR inhibition, the increase of autophagic flux was detected by a decrease of the fluorescent ratio of pHluorin to mCherry; our reporter was also more sensitive to autophagy-inducing stimuli than the previous one. To establish monitoring cells for mouse genome-wide screening of regulators of autophagic flux based on CRISPR/Cas9 system, after evaluating knockout efficiency of clones of Cas9-expressing MEFs, we co-expressed our reporter and confirmed that autophagic flux was impaired in gRNA-mediated knockout of canonical autophagy genes. Finally, we performed genome-wide gRNA screening for genes inhibiting starvation-mediated autophagic flux and identified previously reported genes such as Atgs. Thus, we have successfully established a system for screening of genes regulating autophagic flux with our pHluorin-LC3-mCherry reporter in mice. more...
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- 2019
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17. Isolation and identification of photoproducts from UVA-irradiated mixture of N-nitrosoproline with 2'-deoxyadenosine
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Toshinori Suzuki, Sachiko Kimura, Chiharu Asahi, Tsutomu Hatano, Kayoko Sano, Shuhei Aoyama, and Sakae Arimoto-Kobayashi
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chemistry.chemical_classification ,Reactive oxygen species ,General Chemical Engineering ,2'-deoxyadenosine ,General Physics and Astronomy ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,High-performance liquid chromatography ,0104 chemical sciences ,Adduct ,Amino acid ,chemistry.chemical_compound ,chemistry ,Deoxyadenosine ,sense organs ,Irradiation ,0210 nano-technology ,Sodium nitrite - Abstract
N-Nitrosoproline (NPRO) is known to form endogenously from sodium nitrite and the amino acid proline, and is thought to be non-mutagenic and non-carcinogenic. However, earlier studies in our laboratory showed that irradiated NPRO can be converted directly to a mutagenic compound upon UVA irradiation. We previously investigated the mutagenic spectrum of NPRO on M13mp2 DNA with UVA irradiation, and found a hot spot comprising AT to GC, where there might be a particular photoreaction of adenine residues with NPRO. In the present study, we investigated the reaction of NPRO with 2'-deoxyadenosine (dA) under UVA irradiation, and identified the chemical structures of the photoproducts. Photoproducts from NPRO and dA were isolated and analyzed with HPLC, MS and NMR. (R)-, (S)-2-(2-pyrrolidyl)-2’-deoxyadenosine (P1, P2) and deoxyinosine (dI) were identified from the mixture of dA and NPRO irradiated with UVA. Results suggest that UVA-activated NPRO produces pyrrolidyl cations which react with dA to generate pyrrolidyl-dA adducts. Production of P1 and P2 from irradiated NPRO with dA increased under N2 saturation compared to those under air saturation, while production of P1 and P2 from irradiated solution under O2 saturation was lower compared to that under air. These results suggest that a Type-I mechanism is involved in the photoproduction of P1 and P2. Furthermore, reactive oxygen species generated during photo-reaction in the presence of O2 may act to destroy the activated form of irradiated NPRO to reduce the formation of P1 and P2. The formation of dI in the irradiated mixture of NPRO with dA might mediate NO release from irradiated NPRO. more...
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- 2019
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18. Real-World Clinical Outcomes of Pembrolizumab as Second-Line Therapy for Advanced Urothelial Carcinoma
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Tohru Miyagi, Taiki Kamijima, Takahiro Nohara, Kouji Izumi, Satoshi Yotsuyanagi, Atsushi Mizokami, Chikashi Seto, Hideki Asahi, Kazuyoshi Shigehara, Shohei Kawaguchi, Akinobu Takano, Yoshifumi Kadono, Ryunosuke Nakagawa, Shuhei Aoyama, and Rie Fukuda more...
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Oncology ,medicine.medical_specialty ,Second-line therapy ,business.industry ,Internal medicine ,medicine ,Pembrolizumab ,business ,Urothelial carcinoma - Abstract
Background: Pembrolizumab is currently considered the standard second-line treatment for advanced urothelial carcinoma (UC). This study aimed to investigate the efficacy and safety of pembrolizumab in patients with advanced UC in real-world data, which is not well-reported.Methods: The study included 98 patients with advanced UC who were treated with pembrolizumab after platinum-based chemotherapy at eight hospitals. The efficacy, safety, and risk factors for prognosis were evaluated. Results: The median age was 73 years. Nineteen patients (19%) with performance status (PS) 2-4 were included. The percentages of liver, lung, bone, and lymph node metastasis were 18%, 27%, 19%, and 76%, respectively. The best response was complete response in nine patients (9%) and partial response in 16 patients (17%). The median progression-free survival and overall survival were 3.7 months (95% confidence interval [CI]: 2.8–4.7) and 11.8 months (95% CI: 6.7–17.0), respectively. Poor PS, liver metastasis, and higher C-reactive protein were poor prognostic factors. Hyperprogression was observed in nine patients (9%), who were mostly of poor PS and had high-volume lesions. Severe adverse events (AEs) were observed in 18 patients (19%), and five patients died because of AEs (5%). Atypical AEs, such as pneumocystis pneumonia and acute myeloid leukemia, were observed in our cohort. Conclusion: The efficacy of pembrolizumab for advanced UC in our cohort was better than a previous phase III trial (KEYNOTE-045), possibly owing to lower cancer volume and fewer visceral metastases in our patients. more...
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- 2020
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19. Computed Tomography Using a Low Tube Voltage Technique for Acute Ischemic Stroke
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Masao Tanooka, Shuhei Aoyama, Kenji Nakamura, Katsuhiko Maeda, Noriko Kotoura, and Reiichi Ishikura
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medicine.diagnostic_test ,business.industry ,Mean value ,Significant difference ,Low tube voltage ,Computed tomography ,Hybrid iterative reconstruction ,White matter ,medicine.anatomical_structure ,Medicine ,General Materials Science ,business ,Nuclear medicine ,Acute ischemic stroke - Abstract
Computed tomography (CT) is commonly used to assess for cerebral hemorrhage and acute ischemic stroke. We investigated the accuracy of CT using a low tube voltage technique in acute ischemic stroke. We compared the standard deviation (SD), contrast between gray and white matter, and contrast-to-noise ratio (CNR) between three groups (120 kV 500 mAs, 100 kV 850 mAs, and 100 kV 750 mAs using hybrid iterative reconstruction) in 50 patients without lesions, and visual evaluation using the normalized rank approach was also performed. The mean value of SD was 4.02, 4.22, and 4.04, respectively, and the contrast between gray and white matter was 7.08, 8.66, and 8.68 HU, respectively; in addition, the CNR was 1.77, 2.06, and 2.15, respectively. The difference between the 100 kV and 120 kV groups was significant (p < 0.01). Visual evaluation showed a significant difference between the 100 and 120 kV groups (p < 0.05). more...
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- 2019
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20. Pattern formation analysis by colored Petri nets with quantitative manipulation of a gene
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Yumiko Harada, Ena Yamamoto, Ryutaro Murakami, Tsubasa Saitoh, Katsunobu Shirahama, Hiroshi Matsuno, Fei Liu, and Shuhei Aoyama
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Modeling and simulation ,Multicellular organism ,Colored petri ,Computer science ,Notch signaling pathway ,Pattern formation ,Petri net ,Biological system ,Gene ,Boundary cell - Abstract
We propose a new approach of modeling and simulation for analyzing multicellular biological events by combining colored hybrid Petri nets (CoIHPNs) with newly devised biological experiments that can control the level of a gene quantitatively. We analyzed the patterning of boundary cells in the Drosophila large intestine, where one-cell-wide domain of boundary cells differentiate through Delta-Notch signaling. Biological experiments regulating the level of Delta result in six distinct patterns of boundary cells corresponding with the level of Delta. All these patterns were successfully reproduced by simulation based on ColHPN modeling only by changing the parameter related to the level of Delta. By monitoring the concentration of the active form of Notch in each cell during simulation, it was revealed that these distinct modes of patterning correlate with the fluctuation range of active Notch. Combination of simulation and quantitative manipulation of a gene activity described here is a reliable and powerful approach for analyzing and understanding the patterning process regulated by Notch signaling. more...
- Published
- 2019
- Full Text
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21. Testicular rhabdomyosarcoma after chemotherapy for metastatic germ cell tumors
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Mitsuo Ofude, Ryunosuke Nakagawa, Tohru Miyagi, Kazuyoshi Katayanagi, Yurie Okayama, Satoko Urata, Shuhei Aoyama, and Takao Nakashima
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Pathology ,medicine.medical_specialty ,endocrine system ,business.industry ,Autopsy ,Case Report ,medicine.disease ,urologic and male genital diseases ,Testicular Rhabdomyosarcoma ,medicine.anatomical_structure ,Surgical oncology ,Scrotum ,Medicine ,Germ cell tumors ,Gonadal vein ,business ,Rhabdomyosarcoma ,Germ cell - Abstract
A 36-year-old male was referred to our hospital with left scrotal swelling. Computed tomography revealed a massive tumor in his left scrotum. The tumor extended along the gonadal vein extraperitoneally forming a massive tumor. Pathological examination showed a mixed-type germ cell tumor. Despite several chemotherapeutic treatments, the tumor continued to grow, and the patient died 28 months later after his first presentation at our institution. Autopsy revealed that the tumor comprised rhabdomyosarcoma and mature teratoma. We could not find useful tumor markers to facilitate the diagnosis of rhabdomyosarcoma. However, we recommend rebiopsy or palliative operation as options for re-diagnosis in case of resistant germ cell tumor. Here, we present a case of testicular tumor that exhibited different pathological examination results before and after treatment. more...
- Published
- 2019
22. 2185-P: Estimation of Autophagy Flux by a Novel Fluorescent Reporter in Organs Involved in Glucose Metabolism Including Pancreatic ß Cells
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Shuhei Aoyama, Isei Tanida, Yuya Nishida, Hirotaka Watada, Takeshi Miyatsuka, and Rieko Yazawa
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Downregulation and upregulation ,Chemistry ,Endocrinology, Diabetes and Metabolism ,Autophagy ,Internal Medicine ,Glucose homeostasis ,Pharmacology ,Carbohydrate metabolism ,mCherry ,Flux (metabolism) ,Homeostasis ,Green fluorescent protein - Abstract
Autophagy is a bulk degradation system which plays an important role to maintain cell homeostasis. We have shown that deficiency of autophagy in pancreatic β cells leads to their failure and deterioration of glucose tolerance. On the other hand, there has been controversy over induction of autophagic flux in β cells following different physiological contexts, as it has been difficult to estimate autophagy flux by using conventional methods such as estimation of LC3-lipidation. Recently, application of a novel autophagy flux, GFP-LC3-RFP-LC3ΔG, is reported, which enables us to evaluate autophagy flux by calculating ratio between the fluorescence of GFP and RFP, as GFP-LC3 is degraded specifically in autolysosomes, whereas RFP-LC3ΔG remains intact in cytosol as an internal control. To improve its usefulness, we modified it to construct pHluorin-LC3-mCherry. First, we expressed this probe in MIN6 cells and confirmed decrease of pHluorin/mCherry ratio following induction of autophagic flux in starvation or administration of specific mTOR inhibitor, Torin-1. Next, we generated knock-in mouse in which the probe is expressed under the control of CAG promotor in ROSA26 locus. Its expression was confirmed based on Western blot and fluorescent microscopy in almost all the tissues that we examined. Then we stimulated the mice with starvation and detected that pHluorin/mCherry ratio decreases after starvation in several organs, including liver and muscle which are deeply involved in glucose homeostasis. Finally, we investigated whether autophagic flux is changed after starvation in pancreatic beta cells and successfully demonstrated that the flux is increased following prolonged starvation. In addition, we also illustrated upregulation of autophagic flux in isolated islets after glucose and amino acid starvation. These results show dynamic change of autophagic flux after starvation in many tissues related to glucose homeostasis including βcells. Disclosure S. Aoyama: None. Y. Nishida: None. R. Yazawa: None. I. Tanida: None. T. Miyatsuka: None. H. Watada: Research Support; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Kissei Pharmaceutical Co., Ltd., Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novartis Pharmaceuticals Corporation, Novo Nordisk A/S, Pfizer Inc., Sanofi, Sumitomo Dainippon Pharma Co., Ltd., Takeda Pharmaceutical Company Limited, Teijin Pharma Limited. Speaker's Bureau; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novo Nordisk A/S, Ono Pharmaceutical Co., Ltd., Sanofi, Takeda Pharmaceutical Company Limited, Terumo Medical Corporation. Other Relationship; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Kowa Pharmaceutical Europe Co. Ltd., Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Ono Pharmaceutical Co., Ltd., Sanwa Chemical Industry Co. Ltd., Takeda Pharmaceutical Company Limited. more...
- Published
- 2019
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23. Isolation of new photoadducts from UVA-irradiated N-nitrosoproline with 2'-deoxyadenosine and characterization of photoadducts from DNA irradiated with N-nitrosoproline
- Author
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Chiharu Asahi, Sakae Arimoto-Kobayashi, Shuhei Aoyama, Toshinori Suzuki, Tsutomu Hatano, and Sachiko Kimura
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chemistry.chemical_classification ,Reactive oxygen species ,Stereochemistry ,General Chemical Engineering ,2'-deoxyadenosine ,General Physics and Astronomy ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,High-performance liquid chromatography ,0104 chemical sciences ,Adduct ,chemistry.chemical_compound ,chemistry ,DNA adduct ,Nitrosation ,Proline ,0210 nano-technology ,DNA - Abstract
N-nitrosoproline (NPRO) is formed from nitrosation of proline and has been reported to be non-carcinogenic and non-mutagenic. However, earlier studies in our laboratory showed that pre-irradiated NPRO can be converted to a mutagenic form. We previously investigated the reaction of NPRO with dA or dG under UVA irradiation and identified the formation of 2-pyrrolidyl-dA adducts (P1 & P2) and 8-pyrrolidyl-dG adducts (G1 & G2) as well as four known modified nucleosides, although several peaks found in the HPLC profiles of UVA-irradiated mixtures of dA and NPRO remain unidentified. In the present study we isolated new photoproducts from irradiated mixtures of dA and NPRO and identified (R)- and (S)-8-(2-pyrrolidyl)-2′-deoxyadenosine (A1 and A2) as products by MS and NMR. We also investigated the photoadducts formed in DNA treated with NPRO under UVA irradiation, and detected A1 and/or A2 (probably both), P1, P2, G1 and/or G2, and 8-oxodG as products. Under anaerobic conditions, formation of A1 and A2 was greater than that under aerobic conditions, suggesting that photo-reactions comprising pyrrolidyl radical with dA may increase under anaerobic conditions given reduced competition with oxidative photo-reactions which may decompose pyrrolidyl-dA adducts. more...
- Published
- 2020
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24. Thermally imprinted microcone structure-assisted lateral-flow immunoassay platforms for detecting disease marker proteins
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Kenji Monden, Masumi Yamada, Minoru Seki, Yuto Akiyama, and Shuhei Aoyama
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Materials science ,Surface Properties ,Nanotechnology ,02 engineering and technology ,01 natural sciences ,Biochemistry ,Buffer (optical fiber) ,Analytical Chemistry ,Surface-Active Agents ,Adsorption ,Limit of Detection ,Electrochemistry ,medicine ,Surface roughness ,Environmental Chemistry ,Polymer substrate ,Humans ,Polymethyl Methacrylate ,Polycarbonate ,Spectroscopy ,Detection limit ,chemistry.chemical_classification ,Immunoassay ,Polycarboxylate Cement ,medicine.diagnostic_test ,010401 analytical chemistry ,Temperature ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,C-Reactive Protein ,chemistry ,visual_art ,visual_art.visual_art_medium ,0210 nano-technology ,Antibodies, Immobilized ,Biomarkers - Abstract
Although various types of on-site immunoassay platforms have been developed, facile and reliable sample-to-answer immunoassay systems are still under development. In this study, we proposed a lateral-flow immunoassay system utilizing a polymer sheet with microcone array structures fabricated by thermal imprinting. By adding a surfactant to the running/washing buffer, we were able to dispense with complicated chemical modification protocols, which are usually necessary to enhance antibody adsorption. We investigated three types of polymeric materials and confirmed that polycarbonate is most suitable as an imprinted polymer substrate. Experiments using microcone arrays with different distances revealed that the increased surface area with nanometer-scale surface roughness was key to achieving stable immobilization of antibodies. To assess the applicability of this assay to clinical diagnosis, C-reactive protein in a pure buffer and in a serum sample was analyzed as a model, with a ∼0.1 μg mL−1 lower limit of detection. The presented approach would open a new path to the development of immunoassay-based on-site point-of-care testing by virtue of its simplicity of operation, high sensitivity, and versatility. more...
- Published
- 2018
25. Efficacy of combined prophylactic use of levofloxacin and isepamicin for transrectal prostate needle biopsy: A retrospective single-center study
- Author
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Kouji Izumi, Shuhei Aoyama, Ryunosuke Nakagawa, Tohru Miyagi, Kazuyoshi Shigehara, Takao Nakashima, Satoko Urata, Mitsuo Ofude, and Atsushi Mizokami
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0301 basic medicine ,Microbiology (medical) ,Male ,Carbapenem ,medicine.medical_specialty ,Microbiological culture ,medicine.drug_class ,030106 microbiology ,Antibiotics ,Administration, Oral ,Levofloxacin ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Postoperative Complications ,Internal medicine ,Biopsy ,medicine ,Humans ,Pharmacology (medical) ,030212 general & internal medicine ,Antibiotic prophylaxis ,Ultrasonography, Interventional ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,Bacteria ,business.industry ,Incidence ,Acute prostatitis ,Prostate ,Rectum ,Prostatic Neoplasms ,Antibiotic Prophylaxis ,medicine.disease ,Prostatitis ,Infectious Diseases ,Acute Disease ,Administration, Intravenous ,Drug Therapy, Combination ,Biopsy, Large-Core Needle ,Isepamicin ,Gentamicins ,business ,medicine.drug - Abstract
Purpose To assess the efficacy of a combined regimen of levofloxacin (LVFX) plus isepamicin (ISP) as prophylaxis for transrectal ultrasound-guided needle biopsy of the prostate (TRUSP-Bx). Materials and methods Overall, 562 patients undergoing TRUSP-Bx were included in the present study. All patients were administered a single-dose of oral LVFX (500 mg) in the morning and intravenous ISP (400 mg) 60 min before biopsy. All biopsies were performed via TRUSP-Bx with an 18-gauge needle, and 12-core specimens were routinely obtained. Before initiating antibiotic treatment, urine and blood bacterial cultures were tested to determine the causative microorganisms in the patients with acute bacterial prostatitis. Results Acute bacterial prostatitis developed in three (0.53%) participants. The incidence rates of acute bacterial prostatitis in the low- and high-risk groups were 0.79% and 0.46%, respectively. These patients showed clinical symptoms of acute bacterial prostatitis 12–24 h after their biopsy. Escherichia coli (E. coli) was isolated in the urine or bladder cultures of all of patients. All three isolates were determined to be LVFX-resistant E. coli, although they had good sensitivity to aminoglycosides, cephalosporins, and carbapenems. All patients were administered antibiotic treatment (cephalosporin or carbapenem) immediately and were treated successfully with no evidence of further disease progression. Conclusion Antibiotic prophylaxis with LVFX plus ISP was effective, resulting in a lower incidence of acute bacterial prostatitis after TRUSP-Bx in both low- and high-risk patients. more...
- Published
- 2018
26. Investigation of Touch Interfaces Using Multilayered Urushi Circuit
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Yuki Hashimoto, Shuhei Aoyama, Koshi Ikegawa, Shogo Tsuchikiri, Buntarou Shizuki, and Takuto Nakamura
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Fabrication ,business.industry ,Computer science ,Interface (computing) ,05 social sciences ,020207 software engineering ,Hardware_PERFORMANCEANDRELIABILITY ,02 engineering and technology ,engineering.material ,Coating ,visual_art ,Electrode ,Hardware_INTEGRATEDCIRCUITS ,0202 electrical engineering, electronic engineering, information engineering ,visual_art.visual_art_medium ,engineering ,Optoelectronics ,Natural resin ,0501 psychology and cognitive sciences ,business ,Layer (electronics) ,050107 human factors ,Lacquer ,Hardware_LOGICDESIGN ,Electronic circuit - Abstract
Urushi (Japanese lacquer) is a natural resin paint with electrical insulating capability. By using it as a base material and coating material for electronic circuits, it is possible to construct a circuit with an elegant appearance and feel. It is also possible to build a multilayered electronic circuit by using urushi as insulation layers. In this study, we investigate techniques to construct touch interfaces using a multilayered electronic circuit (urushi circuit). At first, we fabricated an urushi circuit with a touch electrode consisting of two layers. To improve its appearance, we fabricated urushi circuits in which all touch electrodes are arranged on the top layer and all wires are hidden in the bottom layer. Moreover, as an extension of the touch interface, we built a grid of touch electrodes that realizes two-dimensional touch sensing. more...
- Published
- 2018
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27. Analysis of word classes and meanings of the terms appeared in book reviews described both before and after reading
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Takashi HARADA, Shuhei AOYAMA, Mari NISHIYAMA, Kaori TAKEUCHI, and Yui TOKUNAGA
- Published
- 2015
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28. Near ultraviolet radiation-mediated reaction between N-nitrosoproline and DNA: Isolation and identification of two new adducts, (R)- and (S)-8-(2-pyrrolidyl)-2′-deoxyguanosine
- Author
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Toshinori Suzuki, Sachiko Kimura, Kayoko Sano, Tsutomu Hatano, Keinosuke Okamoto, Sakae Arimoto-Kobayashi, Tomoe Negishi, Masaki Machida, Shuhei Aoyama, and Chiharu Asahi
- Subjects
Chemistry ,Guanine ,General Chemical Engineering ,Photodissociation ,General Physics and Astronomy ,General Chemistry ,Photochemistry ,medicine.disease_cause ,High-performance liquid chromatography ,Adduct ,chemistry.chemical_compound ,medicine ,Deoxyguanosine ,Irradiation ,Genotoxicity ,DNA - Abstract
To explore possible genotoxicity of N-nitrosoproline (NPRO), we investigated near-ultraviolet radiation (UVA)-mediated chemical reaction of NPRO with 2′-deoxyguanosine (dG). An acidic solution containing NPRO and dG was irradiated with UVA and products were analyzed by HPLC. In addition to the three known modified guanine nucleosides, i.e., 2′-deoxyxanthosine, 8-oxo-7,8-dihydro-2′-deoxyguanosine and 2′-deoxyoxanosine, we found two products. These new products were isolated and identified as (R)- and (S)-8-(2-pyrrolidyl)-2′-deoxyguanosine (G1 and G2, respectively). Experiments using monochromatic UVA in the range 300–400 nm were performed to determine the relation between products-yield and wavelength, and the highest yields of both G1 and G2 were found to occur at 340 nm. This wavelength coincided with the absorption maximum of NPRO. We propose that the NO radical produced from NPRO by photolysis triggers the formation of these products. Further investigation using calf thymus DNA showed that G1 and/or G2, probably both, could be produced by UVA irradiation of DNA + NPRO as well. more...
- Published
- 2014
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29. Mutagenicity and NO Formation from UVA Irradiated N-Nitrosoproline, and Characterization of Photoproduct Formed in UVA-irradiated Mixture of N-Nitrosoproline with 2^|^prime;-Deoxyguanosine in Neutral Solution
- Author
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Keinosuke Okamoto, Sakae Arimoto-Kobayashi, Kayoko Sano, Shuhei Aoyama, Chiharu Asahi, Tomoe Negishi, Sachiko Kimura, Noriko Tanaka, Toshinori Suzuki, and Masaki Machida
- Subjects
chemistry.chemical_compound ,Social Psychology ,chemistry ,N-nitrosamine ,N-nitrosoproline ,DNA adduct ,Genetics ,Deoxyguanosine ,Irradiation ,Environmental Science (miscellaneous) ,No formation ,Nuclear chemistry - Published
- 2014
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30. ThumbSlide
- Author
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Buntarou Shizuki, Shuhei Aoyama, and Jiro Tanaka
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Computer science ,business.industry ,05 social sciences ,Wearable computer ,020207 software engineering ,02 engineering and technology ,Interaction technique ,Thumb ,body regions ,Smartwatch ,medicine.anatomical_structure ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,0501 psychology and cognitive sciences ,Movement (clockwork) ,Computer vision ,Artificial intelligence ,business ,050107 human factors ,Gesture - Abstract
We present ThumbSlide, which is an interaction technique for a smartwatch that prevents occlusion caused by the user's finger; the technique realizes continuous manipulation by estimating the moving amount of the thumb. Combining with any determining operation (e.g., clench of the hand), our technique enables the user to select a target by only the hand that is wearing a smartwatch. Our system estimates the moving amount of the thumb by muscles' expansion caused by its movement. The muscle expansion is measured by a specially designed wrist-worn sensor device. Moreover, the device can recognize the clench of the hand as an instantaneous change of the wrist's contour. In this paper, we show the implementation of ThumbSlide and its example applications. more...
- Published
- 2016
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31. DEVELOPMENT AND EVALUATION OF A TEMPORARY PLACEMENT AND CONVEYANCE OPERATION SIMULATION SYSTEM USING AUGMENTED REALITY
- Author
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Solhaug Lars Inge, Weida Yan, Masanori Izumi, Hiroshi Shimoda, Shuhei Aoyama, Tran T. Sang, Toppe Aleksander Lygren, Johnsen Terje, and Hirotake Ishii
- Subjects
Engineering ,business.industry ,Control engineering ,Plan (drawing) ,Collision ,Field (computer science) ,Nuclear decommissioning ,law.invention ,Nuclear Energy and Engineering ,Work (electrical) ,law ,Polygon ,Nuclear power plant ,Augmented reality ,business ,Simulation - Abstract
When decommissioning a nuclear power plant, it is difficult to make an appropriate plan to ensure sufficient space for temporary placement and conveyance operations of dismantling targets. This paper describes a system to support temporary placement and conveyance operations using augmented reality (AR). The system employs a laser range scanner to measure the three-dimensional (3D) information of the environment and a dismantling target to produce 3D surface polygon models. Then, the operator simulates temporary placement and conveyance operations using the system by manipulating the obtained 3D model of the dismantling target in the work field. Referring to the obtained 3D model of the environment, a possible collision between the dismantling target and the environment is detectable. Using AR, the collision position is presented intuitively. After field workers evaluated this system, the authors concluded that the system is feasible and acceptable to verify whether spaces for passage and temporary storage are sufficient for temporary placement and conveyance operations. For practical use in the future, some new functions must be added to improve the system. For example, it must be possible for multiple workers to use the system simultaneously by sharing the view of dismantling work. more...
- Published
- 2012
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32. Study on Establishment of Electric Equivalent Model of Fuel Cell
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Naoki Yamamura, Muneaki Ishida, and Shuhei Aoyama
- Subjects
Equivalent model ,Materials science ,Nuclear engineering ,Fuel cells - Published
- 2008
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33. Hover Detection Using Active Acoustic Sensing
- Author
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Shuhei Aoyama, Jiro Tanaka, Masaya Tsuruta, Buntarou Shizuki, and Arika Yoshida
- Subjects
business.industry ,Computer science ,Piezoelectric sensor ,Property (programming) ,020207 software engineering ,02 engineering and technology ,Object (computer science) ,Piezoelectricity ,Proximity sensing ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Ultrasonic sensor ,Computer vision ,Artificial intelligence ,business - Abstract
In this paper, we present a technique for hover and touch detection using Active Acoustic Sensing. This sensing technique analyzes the resonant property of the target object and the air around it. To verify whether the detection technique works, we conduct an experiment to discriminate between hovering the hand over the piezoelectric elements placed on a target object and touching the same object. As a result of our experiment, hovering was detected with 96.7i¾?% accuracy and touching was detected with 100i¾?% accuracy. more...
- Published
- 2016
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34. Decentralized Formation Flight Control Using Virtual Structure and Backstepping
- Author
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Hirohisa Kojima and Shuhei Aoyama
- Subjects
Scheme (programming language) ,Engineering ,Spacecraft ,SIMPLE (military communications protocol) ,business.industry ,Mechanical Engineering ,Control (management) ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,Control engineering ,Industrial and Manufacturing Engineering ,Computer Science::Systems and Control ,Mechanics of Materials ,Control theory ,Backstepping ,Key (cryptography) ,Virtual structure ,business ,computer ,computer.programming_language - Abstract
Formation-flight, which involves multiple spacecraft, is a key technology to conduct future space applications. The formation flight of multiple spacecraft using virtual structure approach and backstepping method is proposed. Decentralized scheme is used for information communication, and two simple anti-windup methods are studied to avoid the controller saturation tuning of backstepping controller gains, and tuning of virtual structure controller gains. Numerical simulations show that the proposed controller, which combines the virtual structure approach with backstepping method, can achieve formation flight effectively. more...
- Published
- 2006
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35. Significant suppression of Rayleigh scattering loss in silica glass formed by the compression of its melted phase
- Author
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Masanori Fujinami, Setsuro Ito, Shuhei Aoyama, and Madoka Ono
- Subjects
010302 applied physics ,Materials science ,Silica glass ,business.industry ,Physics::Optics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Compression (physics) ,Condensed Matter::Disordered Systems and Neural Networks ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Light scattering ,Condensed Matter::Soft Condensed Matter ,symbols.namesake ,Optics ,Phase (matter) ,0103 physical sciences ,symbols ,Fiber ,Rayleigh scattering ,Composite material ,0210 nano-technology ,business ,Spectroscopy ,Refractive index - Abstract
We propose the formation of silica glass with improved optical transport properties by compressing its melted phase with a hot isostatic pressure machine at high pressure and temperature. The lowest Rayleigh scattering loss was obtained for the glass held at 200 MPa and 2073 K for 4 h. The observed loss corresponds to 0.07 dB/Km at 1.55 μm, which is about half of the loss in conventional silica glass fiber. The decrease in the loss was well explained in terms of the decrease in the size of the sub-nanometer-sized structural voids observed by positron annihilation lifetime spectroscopy in silica glass. The achievement of high transparency and strong confinement of light represents a promising result for the development of future fiber-core media. more...
- Published
- 2018
- Full Text
- View/download PDF
36. Spatial Clearance Verification Using 3D Laser Range Scanner and Augmented Reality
- Author
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Weida Yan, Masanori Izumi, Hiroshi Shimoda, Yoshihito Ono, Shuhei Aoyama, and Hirotake Ishii
- Subjects
Scanner ,Work (electrical) ,law ,Computer science ,Range (statistics) ,Augmented reality ,Workspace ,Laser ,Field (computer science) ,Simulation ,law.invention - Abstract
A spatial clearance verification system for supporting nuclear power plant dismantling work was developed and evaluated by a subjective evaluation. The system employs a three-dimensional laser range scanner to obtain threedimensional surface models of work environment and dismantling targets. The system also employs Augmented Reality to allow field workers to perform simulation of transportation and temporal placement of dismantling targets using the obtained models to verify spatial clearance in actual work environments. The developed system was evaluated by field workers. The results show that the system is acceptable and useful to confirm that dismantling targets can be transported through narrow passages and can be placed in limited temporal workspaces. It was also found that the extension of the system is desirable to make it possible for multiple workers to use the system simultaneously to share the image of the dismantling work. more...
- Published
- 2011
- Full Text
- View/download PDF
37. 3317 Formation Flight Using Virtual Structure and Backstepping
- Author
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Shuhei Aoyama and Hirohisa Kojima
- Subjects
Control theory ,Computer science ,Backstepping ,Control engineering ,Virtual structure - Published
- 2005
- Full Text
- View/download PDF
38. Formation flight using feature-based visual servo technique
- Author
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Kouichi Yajima, Shuhei Aoyama, and Hirohisa Kojima
- Subjects
Scheme (programming language) ,Spacecraft ,Computer simulation ,Computer science ,business.industry ,Control (management) ,Control engineering ,Image (mathematics) ,Position (vector) ,Feature based ,Computer vision ,Artificial intelligence ,business ,computer ,Servo ,computer.programming_language - Abstract
This paper proposes a control scheme to achieve a formation flight of spacecrafts. This proposed method is based on a feature based visual servo technique, which uses image data taken by a camera and is applicable to controlling systems such as robot manipulator and vehicles installed with cameras. This technique does not require accurate current position and attitude data for controlling the system if the image data taken at the goal position/attitude is obtained in advance, because the current position and attitude can be determined from the difference between current visual data and goal image data. Thus, for the case that the measurement sensor is an on-board camera only, this technique is more desired one to achieve a formation flight. A numerical simulation for the proposed control is conducted to demonstrate the effectiveness of the present control scheme. more...
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