275 results on '"Tomoko Yamaguchi"'
Search Results
2. Plasma extracellular vesicle microRNAs reflecting the therapeutic effect of the CBP/β-catenin inhibitor PRI-724 in patients with liver cirrhosis
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Mayu Yoshida, Juntaro Matsuzaki, Koji Fujita, Masamichi Kimura, Tomohiro Umezu, Noi Tokuda, Tomoko Yamaguchi, Masahiko Kuroda, Takahiro Ochiya, Yoshimasa Saito, and Kiminori Kimura
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Extracellular vesicle ,miRNA ,Antifibrotic therapy ,Medicine ,Science - Abstract
Abstract There is an unmet need for antifibrotic therapies to prevent the progression of liver cirrhosis. Previously, we conducted an exploratory trial to assess the safety and antifibrotic efficacy of PRI-724, a selective CBP/β-catenin inhibitor, in patients with liver cirrhosis. PRI-724 was well tolerated and exerted a potential antifibrotic effect. Here, we investigated whether the profiles of circulating microRNAs packaged in extracellular vesicles (EV-miRNAs) are associated with responses to liver fibrosis treatments. Eighteen patients who received PRI-724 for 12 weeks in a phase 1/2a study were classified as responders (n = 10) or non-responders (n = 8) based on changes in liver stiffness. Plasma samples were obtained before and after PRI-724 administration and the levels of EV-miRNAs were analyzed. Three miRNAs (miR-6510-5p, miR-6772-5p, and miR-4261) were identified as predictors of response or non-response to PRI-724, and the levels of three other miRNAs (miR-939-3p, miR-887-3p, and miR-7112-5p) correlated with the efficacy of treatment. Expression of miR-887-3p was detected in hepatocytes and was decreased significantly in liver tissue following PRI-724 treatment. In addition, transfection of a miR-887-3p mimic activated hepatic stellate cells. Thus, decreases in the miR-887-3p level in blood may reflect recovery from liver fibroses in patients with liver cirrhosis treated with PRI-724, although further validation studies are warranted to confirm this.
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- 2024
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3. Predicting postpartum hemorrhage in women undergoing planned cesarean section: A multicenter retrospective cohort study in Japan.
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Tomoko Yamaguchi, Hyo Kyozuka, Momoka Ito, Tsuyoshi Hiraiwa, Tsuyoshi Murata, Misa Sugeno, Fumihiro Ito, Daisuke Suzuki, Toma Fukuda, Shun Yasuda, Fujimori Keiya, and Yasuhisa Nomura
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Medicine ,Science - Abstract
Given Japan's unique social background, it is critical to understand the current risk factors for postpartum hemorrhage (PPH) to effectively manage the condition, especially among specific groups. Therefore, this study aimed to identify the current risk factors for PPH during planned cesarean section (CS) in Japan. This multicenter retrospective cohort study was conducted in two tertiary maternal-fetal medicine units in Fukushima, Japan and included 1,069 women who underwent planned CS between January 1, 2013, and December 31, 2022. Risk factors for PPH (of > 1000 g and > 1500 g) were assessed using multivariate logistic regression analysis, considering variables such as maternal age, parity, assisted reproductive technology (ART) pregnancy, pre-pregnancy body mass index (BMI), uterine myoma, placenta previa, gestational age at delivery, birth weight categories, and hypertensive disorders of pregnancy (HDP). Multivariate linear regression analyses were conducted to predict estimated blood loss during planned CS. ART pregnancy, a pre-pregnancy BMI of 25.0-29.9 kg/m2, and uterine myoma increased PPH risk at various levels. Maternal smoking increased the risk of >1500 g PPH (adjusted odds ratio: 3.09, 95% confidence interval [CI]: 1.16-8.20). Multivariate linear analysis showed that advanced maternal age (B: 83 g; 95% CI: 27-139 g), ART pregnancy (B: 239 g; 95% CI: 121-357 g), pre-pregnancy BMI of 25.0-29.9 kg/m2 (B: 74 g; 95% CI: 22-167 g), uterine myoma (B: 151 g; 95% CI: 47-256 g), smoking (B: 107 g; 95% CI: 13-200 g), and birth weight > 3,500 g (B: 203 g; 95% CI: 67-338 g) were associated with blood loss during planned CS. Considering a patient's clinical characteristic may help predict bleeding in planned CSs and help improve patient safety.
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- 2024
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4. The maturation of iPS cell-derived brain microvascular endothelial cells by inducible-SOX18 expression
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Hongyan Zhang, Tomoko Yamaguchi, and Kenji Kawabata
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Blood-brain-barrier ,Brain microvascular endothelial cells ,Sox18 ,Transcription factors ,Maturation ,Differentiation ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Brain microvascular endothelial cells (BMECs) play a major role in the blood–brain barrier (BBB), and are critical for establishing an in vitro BBB model. Currently, iPSC-derived BMECs (iBMECs) have been used to construct in vitro BBB models with physiological barrier functions, such as high trans-endothelial electrical resistance (TEER) and expression of transporter proteins. However, the relatively low p-glycoprotein (P-gp) level and a decrease in the efflux ratio of its substrates in iBMECs suggest their immature nature. Therefore, more mature iBMECs by optimizing the differentiation induction protocol is beneficial for establishing a more reliable in vitro BBB model for studying central nervous system (CNS) drug transport. Methods To identify human brain endothelial cell fate-inducing factors, HUVEC was transfected with Zic3A-, Zic3B-, and Sox18-expressing lentivirus vector. Since SOX18 was found to induce BMEC properties, we used a Dox-inducible Tet-on system to express SOX18 during iBMEC differentiation and explored the impact of SOX18 expression on iBMEC maturation. Results Sox18-mediated iBMECs achieved a higher TEER value than normal iBMECs (> 3000 Ω cm2). From day 6 to day 10 (d6–10 group), the iBMECs with SOX18 expression expressed a series of tight junction markers and showed upregulation of Mfsd2a, a specific marker of the BBB. The d6–10 group also expressed SLC2A1/Glut1 at levels as high as normal iBMECs, and upregulated ABCB1/P-gp and ABCC1/MRP1 expression. Moreover, Sox18-mediated iBMECs showed higher viability than normal iBMECs after puromycin treatment, indicating that SOX18 expression could upregulate P-gp activity in iBMECs. Conclusions Inducible SOX18 expression in iBMECs gained BBB phenotypes, including high TEER values and upregulation of tight junction-related genes, endothelial cell (EC) markers, BBB transporters, and higher cell viability after treatment with puromycin. Collectively, we provide a differentiation method for the maturation of human iPS cell-derived BMECs with SOX18 expression, describing its contribution to form an in vitro BBB model for CNS drug transport studies.
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- 2023
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5. Clinical study of skill assessment based on time sequential measurement changes
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Tomoko Yamaguchi, Ryoichi Nakamura, Akihito Kuboki, and Nobuyoshi Otori
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Medicine ,Science - Abstract
Abstract Endoscopic sinus surgery is a common procedure for chronic sinusitis; however, complications have been reported in some cases. Improving surgical outcomes requires an improvement in a surgeon’s skills. In this study, we used surgical workflow analysis to automatically extract “errors,” indicating whether there was a large difference in the comparative evaluation of procedures performed by experts and residents. First, we quantified surgical features using surgical log data, which contained surgical instrument information (e.g., tip position) and time stamp. Second, we created a surgical process model (SPM), which represents the temporal transition of the surgical features. Finally, we identified technical issues by creating an expert standard SPM and comparing it to the novice SPM. We verified the performance of our methods by using the clinical data of 39 patients. In total, 303 portions were detected as an error, and they were classified into six categories. Three risky operations were overlooked, and there were 11 overdetected errors. We noted that most errors detected by our method involved dangers. The implementation of our methods of automatic improvement points detection may be advantageous. Our methods may help reduce the time for reviewing and improving the surgical technique efficiently.
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- 2022
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6. Structure of the molecular bushing of the bacterial flagellar motor
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Tomoko Yamaguchi, Fumiaki Makino, Tomoko Miyata, Tohru Minamino, Takayuki Kato, and Keiichi Namba
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Science - Abstract
In the basal body of the bacterial flagellum, the LP ring acts as a bushing supporting the distal rod for its rapid and stable rotation. Here, Yamaguchi et al. present the electron cryomicroscopy structure of the LP ring around the rod, shedding light into potential mechanisms involved in stability and assembly of the structure.
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- 2021
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7. Generation of functional liver organoids on combining hepatocytes and cholangiocytes with hepatobiliary connections ex vivo
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Naoki Tanimizu, Norihisa Ichinohe, Yasushi Sasaki, Tohru Itoh, Ryo Sudo, Tomoko Yamaguchi, Takeshi Katsuda, Takafumi Ninomiya, Takashi Tokino, Takahiro Ochiya, Atsushi Miyajima, and Toshihiro Mitaka
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Science - Abstract
Combining mouse hepatocyte progenitors and cholangiocytes ex vivo, the authors form an organoid that can drain bile ex vivo and transport metabolites, as in the liver.
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- 2021
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8. Correction: Generation of human hepatic progenitor cells with regenerative and metabolic capacities from primary hepatocytes
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Takeshi Katsuda, Juntaro Matsuzaki, Tomoko Yamaguchi, Yasuhiro Yamada, Marta Prieto-Vila, Kazunori Hosaka, Atsuko Takeuchi, Yoshimasa Saito, and Takahiro Ochiya
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Medicine ,Science ,Biology (General) ,QH301-705.5 - Published
- 2022
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9. Association between Gestational Weight Gain and Risk of Hypertensive Disorders of Pregnancy among Women with Obesity: A Multicenter Retrospective Cohort Study in Japan
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Momoka Ito, Hyo Kyozuka, Tomoko Yamaguchi, Misa Sugeno, Tsuyoshi Murata, Tsuyoshi Hiraiwa, Fumihiro Ito, Daisuke Suzuki, Toma Fukuda, Shun Yasuda, Keiya Fujimori, and Yasuhisa Nomura
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body mass index ,gestational weight gain ,obesity ,preconception care ,hypertensive disorders of pregnancy ,Nutrition. Foods and food supply ,TX341-641 - Abstract
The relationship between weight gain during pregnancy and the onset of hypertensive disorders of pregnancy in women with pre-pregnancy obesity remains unclear. We examined the effects of weight gain during pregnancy on hypertensive disorders of pregnancy among women with pre-pregnancy body mass index (BMI) ≥ 25.0 kg/m2. This multicenter retrospective cohort study included nullipara women who delivered at two units in Japan between 1 January 2013, and 31 December 2020. Singleton primipara (n = 3040) were categorized into two pre-pregnancy BMI groups: 25.0–2. Using multiple logistic regression analyses (reported as adjusted odds ratio and 95% confidence interval), gestational weight gain effects on overall hypertensive disorders of pregnancy, gestational hypertension, and pre-eclampsia were determined. Gestational weight gain increased hypertensive disorders of pregnancy (1.09, 1.03–1.16, p < 0.05) and pre-eclampsia risk (1.10, 1.01–1.20, p < 0.05) among the BMI 25.0–2 group and hypertensive disorders of pregnancy risk among the ≥30.0 kg/m2 group (1.07, 1.00–1.05, p < 0.05). Using receiver operating characteristic curve analyses, among the BMI 25.0–2 group, for hypertensive disorders of pregnancy (area under the curve [AUC], 0.63, p < 0.05) and pre-eclampsia (AUC, 0.62; p < 0.05), the weight gain cut-off was 10.5 and 10.6 kg, with sensitivity/specificity of 0.47/0.73 and 0.50/0.73, respectively. For the BMI ≥30.0 kg/m2 group (AUC, 0.63, p < 0.05), the cut-off was 3.5 kg (sensitivity/specificity, 0.75/0.49). The optimal gestational weight gain for reducing hypertensive disorders of pregnancy among women with a pre-pregnancy BMI > 25 kg/m2 may facilitate personalized pre-conception counseling among women with obesity.
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- 2023
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10. Brain microvascular endothelial cells derived from human induced pluripotent stem cells as in vitro model for assessing blood-brain barrier transferrin receptor-mediated transcytosis
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Marie Piantino, Fiona Louis, Yukari Shigemoto-Mogami, Kimiko Kitamura, Kaoru Sato, Tomoko Yamaguchi, Kenji Kawabata, Syunsuke Yamamoto, Shinji Iwasaki, Hideki Hirabayashi, and Michiya Matsusaki
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Blood-brain barrier ,In vitro model ,Tight junction ,Transferrin receptor ,Receptor-mediated transcytosis ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
The blood-brain barrier (BBB), a selective barrier formed by brain microvascular endothelial cells (BMEC), represents a major challenge for the efficient accumulation of pharmaceutical drugs into the brain. The receptor-mediated transcytosis (RMT) has recently gained increasing interest for pharmaceutical industry as it shows a great potential to shuttle large-sized therapeutic cargos across the BBB. Confirming the presence of the RMT pathway by BMEC is therefore important for the screening of peptides or antibody libraries that bind RMT receptors. Herein, a comparative study was performed between a human cell line of BMEC (HBEC) and human induced pluripotent stem cells-derived BMEC-like cells (hiPS-BMEC). The significantly higher gene and protein expressions of transporters and tight junction proteins, excepting CD31 and VE-cadherin were exhibited by hiPS-BMEC than by HBEC, suggesting more biomimetic BBB features of hiPS-BMEC. The presence and functionality of transferrin receptor (TfR), known to use RMT pathway, were confirmed using hiPS-BMEC by competitive binding assays and confocal microscopy observations. Finally, cysteine-modified T7 and cysteine modified-Tfr-T12 peptides, previously reported to be ligands of TfR, were compared regarding their permeability using hiPS-BMEC. The hiPS-BMEC could be useful for the identification of therapeutics that can be transported across the BBB using RMT pathway.
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- 2022
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11. Design and Development of an HBT-Based Ratiometric Fluorescent Probe to Monitor Stress-Induced Premature Senescence
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Juliann Nzembi Makau, Ayako Kitagawa, Kanami Kitamura, Tomoko Yamaguchi, and Satoshi Mizuta
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Chemistry ,QD1-999 - Published
- 2020
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12. Transcriptomic Dissection of Hepatocyte Heterogeneity: Linking Ploidy, Zonation, and Stem/Progenitor Cell CharacteristicsSummary
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Takeshi Katsuda, Kazunori Hosaka, Juntaro Matsuzaki, Wataru Usuba, Marta Prieto-Vila, Tomoko Yamaguchi, Atsunori Tsuchiya, Shuji Terai, and Takahiro Ochiya
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Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background & Aims: There is a long-standing debate regarding the biological significance of polyploidy in hepatocytes. Recent studies have provided increasing evidence that hepatocytes with different ploidy statuses behave differently in a context-dependent manner (eg, susceptibility to oncogenesis, regenerative ability after injury, and in vitro proliferative capacity). However, their overall transcriptomic differences in a physiological context is not known. Methods: By using microarray transcriptome analysis, we investigated the heterogeneity of hepatocyte populations with different ploidy statuses. Moreover, by using single-cell quantitative reverse-transcription polymerase chain reaction (scPCR) analysis, we investigated the intrapopulational transcriptome heterogeneity of 2c and 4c hepatocytes. Results: Microarray analysis showed that cell cycle–related genes were enriched in 8c hepatocytes, which is in line with the established notion that polyploidy is formed via cell division failure. Surprisingly, in contrast to the general consensus that 2c hepatocytes reside in the periportal region, in our bulk transcriptome and scPCR analyses, the 2c hepatocytes consistently showed pericentral hepatocyte-enriched characteristics. In addition, scPCR analysis identified a subpopulation within the 2c hepatocytes that co-express the liver progenitor cell markers Axin2, Prom1, and Lgr5, implying the potential biological relevance of this subpopulation. Conclusions: This study provides new insights into hepatocyte heterogeneity, namely 2c hepatocytes are preferentially localized to the pericentral region, and a subpopulation of 2c hepatocytes show liver progenitor cell–like features in terms of liver progenitor cell marker expression (Axin2, Prom1, and Lgr5). Keywords: Hepatocyte, Ploidy, Zonation, Single-Cell PCR, Transcriptome
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- 2020
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13. Generation of functional human hepatocytes in vitro: current status and future prospects
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Tomoko Yamaguchi, Juntaro Matsuzaki, Takeshi Katsuda, Yoshimasa Saito, Hidetsugu Saito, and Takahiro Ochiya
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Hepatocyte ,Regeneration ,Progenitor cells ,Drug metabolism ,Pathology ,RB1-214 - Abstract
Abstract Liver and hepatocyte transplantation are the only effective therapies for late-stage liver diseases, in which the liver loses its regenerative capacity. However, there is a shortage of donors. As a potential alternative approach, functional hepatocytes were recently generated from various cell sources. Analysis of drug metabolism in the human liver is important for drug development. Consequently, cells that metabolize drugs similar to human primary hepatocytes are required. This review discusses the current challenges and future perspectives concerning hepatocytes and hepatic progenitor cells that have been reprogrammed from various cell types, focusing on their functions in transplantation models and their ability to metabolize drugs.
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- 2019
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14. Premorbid physical activity is modestly associated with gait independence after a stroke: an exploratory study
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Tomoko Yamaguchi, Osamu Yamamura, Tadanori Hamano, Kazuhiro Murakita, and Yasunari Nakamoto
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Gait independence ,Premorbid physical activities ,Questionnaire ,Stroke ,Cerebrovascular disease ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background Regaining physical function after a stroke is important for independence and for performing activities of daily living. Particularly, cerebrovascular disease, which includes stroke, is not entirely avoidable. In the present study, we aimed to observe the association between premorbid physical activities and gait independence after a stroke. Methods Consecutive cerebrovascular stroke patients were asked to fill a questionnaire regarding their premorbid physical activities. The association between gait independence at the completion of in-hospital rehabilitation and premorbid physical activities, as well as age, stroke type, lesion size, and comorbidities, was investigated statistically. Results Of 130 consecutive patients with stroke who answered the questionnaire regarding their premorbid physical activities, 97 regained gait independence. Ambulation and occupational or household activities were most frequently performed by all the participants before stroke onset. Participants who acquired gait independence tended to indicate various premorbid activities compared to participants who did not recover gait independence. Estimating premorbid physical activities in metabolic equivalents suggested that moderate to vigorous activities were associated with an increased probability of post-stroke independent gait but this tendency was dismissed after multivariate analysis including age and history of stroke. Conclusions Premorbid physical activity is associated with gait independence after a stroke, but this association is not as strong as those of age or history of stroke.
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- 2018
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15. Identification and Modification of Porphyromonas gingivalis Cysteine Protease, Gingipain, Ideal for Screening Periodontitis
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Kimito Hirai, Tomoko Yamaguchi-Tomikawa, Toru Eguchi, Hiroshi Maeda, and Shogo Takashiba
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screening chronic periodontitis ,Porphyromonas gingivalis ,serum IgG test ,gingipain ,specific antigen ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Chronic periodontitis is an inflammatory disease caused by the formation of oral microbial biofilms. Periodontitis is associated with general health and not only oral diseases. Porphyromonas gingivalis is a well-known keystone pathogen for periodontitis and is associated with several systemic diseases, such as diabetes mellitus and Alzheimer's disease. We previously developed a system for screening periodontitis using P. gingivalis-specific serum immunoglobulin G (IgG) in an enzyme-linked immunosorbent assay with a sensitivity of 0.774 and a specificity of 0.586 and an area under the receiver operating characteristic curve of 0.708. However, the antigens elicited non-specific responses, since they were obtained from whole extracts of sonicated cultured bacteria. The purpose of this study was to identify antigens ideal for a sensitive and specific serum test. We identified the specific antigens using immunoaffinity columns immobilized with IgG antibodies from periodontitis patients. Liquid chromatography-tandem mass spectrometry identified 29 antigens from the elutes. Recombinant proteins for these candidates were synthesized using the wheat germ cell-free translation system and screened by dot blot analysis with serum from the columns. Three of the 16 candidates that reacted showed strongest affinities upon dot blot analysis; they included outer membrane protein 28, cysteine proteases, lysine gingipain Kgp, and arginine gingipain RgpA. Outer membrane protein 28 was not suitable for screening P. gingivalis infection because of its high false-negative rates. Kgp and RgpA were unstable antigens since they underwent self-digestion. They were made stable by substituting the active cysteine residues in Kgp and RgpA with alanine using site-directed mutagenesis. Using the modified antigens, we demonstrated that the patient serum IgG level against RgpA was the highest among all the antigens expressed in P. gingivalis. Moreover, the N-terminus of recombinant RgpA was excellent in differentiating between diseased and non-diseased states (with sensitivity of 0.85, specificity of 0.9, and area under the curve of 0.915). Although dot blot analysis was the only experiment used, the N-terminus of RgpA is an excellent antigen to immunologically test for P. gingivalis infection, especially for estimating the risks for periodontitis-associated systemic diseases. In conclusion, we have developed a P. gingivalis antigen for screening periodontitis.
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- 2020
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16. Generation of human hepatic progenitor cells with regenerative and metabolic capacities from primary hepatocytes
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Takeshi Katsuda, Juntaro Matsuzaki, Tomoko Yamaguchi, Yasuhiro Yamada, Marta Prieto-Vila, Kazunori Hosaka, Atsuko Takeuchi, Yoshimasa Saito, and Takahiro Ochiya
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hepatocyte ,liver progenitor cell ,transplantation ,liver repopulation ,cytochrome P450 ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Hepatocytes are regarded as the only effective cell source for cell transplantation to treat liver diseases; however, their availability is limited due to a donor shortage. Thus, a novel cell source must be developed. We recently reported that mature rodent hepatocytes can be reprogrammed into progenitor-like cells with a repopulative capacity using small molecule inhibitors. Here, we demonstrate that hepatic progenitor cells can be obtained from human infant hepatocytes using the same strategy. These cells, named human chemically induced liver progenitors (hCLiPs), had a significant repopulative capacity in injured mouse livers following transplantation. hCLiPs redifferentiated into mature hepatocytes in vitro upon treatment with hepatic maturation-inducing factors. These redifferentiated cells exhibited cytochrome P450 (CYP) enzymatic activities in response to CYP-inducing molecules and these activities were comparable with those in primary human hepatocytes. These findings will facilitate liver cell transplantation therapy and drug discovery studies.
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- 2019
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17. Effect of heat stress on blood-brain barrier integrity in iPS cell-derived microvascular endothelial cell models.
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Tomoko Yamaguchi, Kentaro Shimizu, Yasuhiro Kokubu, Misae Nishijima, Shuko Takeda, Hiroshi Ogura, and Kenji Kawabata
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Medicine ,Science - Abstract
The incidence of heatstroke has been increasing. Heatstroke has been shown to affect physiological barrier functions. However, there are few studies of the effect of heat stress on the blood-brain barrier (BBB) function. In this study, we investigated the influence of heat stress on brain microvascular endothelial cells in vivo and in vitro. Heatstroke model mice administered Texas Red-dextran showed leakage outside the brain vessel walls. In addition, trans-endothelial electrical resistance (TEER) value was significantly reduced in induced pluripotent stem (iPS) cell-derived brain microvascular endothelial cells under heat stress by reducing claudin-5 expression. In addition, our results showed that the expression level of P-glycoprotein (P-gp) was increased in iPS cell-derived brain microvascular endothelial cells under heat stress. Furthermore, serum from heatstroke model mice could impair the BBB integrity of iPS cell-derived brain microvascular endothelial cells. These results suggest that BBB integrity was affected by heat stress in vivo and in vitro and provide important insights into the development of new therapeutic strategies for heatstroke patients.
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- 2019
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18. C4d Deposition in Fetal Vessels of the Placenta in Neonatal Lupus Syndrome
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Yuichiro Sato, Tomoko Yamaguchi, Jyunsuke Muraoka, Hajime Taniguchi, Atsushi Kisanuki, Kazunari Maekawa, Atushi Yamashita, Murasaki Aman, Yuki Kodama, Hiroshi Sameshima, and Yujiro Asada
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Gynecology and obstetrics ,RG1-991 - Abstract
Neonatal lupus syndrome (NLS) is a rare, passively acquired autoimmune syndrome caused by maternal autoantibodies. We describe a case of a newborn with NLS and the accompanying placental findings. A female neonate was born by emergency cesarean delivery due to non-reassuring fetal status at 35 weeks and 3 days. This neonate had congenital erythematous and scar lesions on the face, back, and upper and lower extremities. Maternal and fetal anti-SSA and SSB antibodies were elevated and this baby was diagnosed as NLS. Histologically, the chorionic villi demonstrated capillary shrinkage. An immunohistochemical study revealed complement deposition (C4d) in the capillaries of the villi and umbilical vessels. Our findings suggest that maternal autoantibodies affect the inflammatory response of the fetus through the placenta and that C4d deposition may be useful for diagnosing NLS.
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- 2019
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19. Regulatory Potential of bHLH-Type Transcription Factors on the Road to Rubber Biosynthesis in Hevea brasiliensis
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Tomoko Yamaguchi, Yukio Kurihara, Yuko Makita, Emiko Okubo-Kurihara, Ami Kageyama, Emi Osada, Setsuko Shimada, Hiroko Tsuchida, Hiroaki Shimada, and Minami Matsui
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bHLH ,transcription factor ,rubber ,jasmonate ,Botany ,QK1-989 - Abstract
Natural rubber is the main component of latex obtained from laticifer cells of Hevea brasiliensis. For improving rubber yield, it is essential to understand the genetic molecular mechanisms responsible for laticifer differentiation and rubber biosynthesis. Jasmonate enhances both secondary laticifer differentiation and rubber biosynthesis. Here, we carried out time-course RNA-seq analysis in suspension-cultured cells treated with methyljasmonic acid (MeJA) to characterize the gene expression profile. Gene Ontology (GO) analysis showed that the term “cell differentiation” was enriched in upregulated genes at 24 h after treatment, but inversely, the term was enriched in downregulated genes at 5 days, indicating that MeJA could induce cell differentiation at an early stage of the response. Jasmonate signaling is activated by MYC2, a basic helix–loop–helix (bHLH)-type transcription factor (TF). The aim of this work was to find any links between transcriptomic changes after MeJA application and regulation by TFs. Using an in vitro binding assay, we traced candidate genes throughout the whole genome that were targeted by four bHLH TFs: Hb_MYC2-1, Hb_MYC2-2, Hb_bHLH1, and Hb_bHLH2. The latter two are highly expressed in laticifer cells. Their physical binding sites were found in the promoter regions of a variety of other TF genes, which are differentially expressed upon MeJA exposure, and rubber biogenesis-related genes including SRPP1 and REF3. These studies suggest the possibilities that Hb_MYC2-1 and Hb_MYC2-2 regulate cell differentiation and that Hb_bHLH1 and Hb_bHLH2 promote rubber biosynthesis. We expect that our findings will help to increase natural rubber yield through genetic control in the future.
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- 2020
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20. Structural and Functional Comparison of Salmonella Flagellar Filaments Composed of FljB and FliC
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Tomoko Yamaguchi, Shoko Toma, Naoya Terahara, Tomoko Miyata, Masamichi Ashihara, Tohru Minamino, Keiichi Namba, and Takayuki Kato
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bacterial flagellar motility ,flagellin ,salmonella ,fljb ,flic ,electron cryomicroscopy ,viscosity ,infection ,Microbiology ,QR1-502 - Abstract
The bacterial flagellum is a motility organelle consisting of a long helical filament as a propeller and a rotary motor that drives rapid filament rotation to produce thrust. Salmonella enterica serovar Typhimurium has two genes of flagellin, fljB and fliC, for flagellar filament formation and autonomously switches their expression at a frequency of 10−3−10−4 per cell per generation. We report here differences in their structures and motility functions under high-viscosity conditions. A Salmonella strain expressing FljB showed a higher motility than one expressing FliC under high viscosity. To examine the reasons for this motility difference, we carried out structural analyses of the FljB filament by electron cryomicroscopy and found that the structure was nearly identical to that of the FliC filament except for the position and orientation of the outermost domain D3 of flagellin. The density of domain D3 was much lower in FljB than FliC, suggesting that domain D3 of FljB is more flexible and mobile than that of FliC. These differences suggest that domain D3 plays an important role not only in changing antigenicity of the filament but also in optimizing motility function of the filament as a propeller under different conditions.
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- 2020
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21. Adenovirus Vector-Derived VA-RNA-Mediated Innate Immune Responses
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Hiroyuki Mizuguchi, Kenji Kawabata, Fuminori Sakurai, Kazufumi Katayama, Mitsuhiro Machitani, Kahori Shimizu, and Tomoko Yamaguchi
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adenovirus vector ,VA-RNA ,gene therapy ,innate immunity ,Pharmacy and materia medica ,RS1-441 - Abstract
The major limitation of the clinical use of replication-incompetent adenovirus (Ad) vectors is the interference by innate immune responses, including induction of inflammatory cytokines and interferons (IFN), following in vivo application of Ad vectors. Ad vector-induced production of inflammatory cytokines and IFNs also results in severe organ damage and efficient induction of acquired immune responses against Ad proteins and transgene products. Ad vector-induced innate immune responses are triggered by the recognition of Ad components by pattern recognition receptors (PRRs). In order to reduce the side effects by Ad vector-induced innate immune responses and to develop safer Ad vectors, it is crucial to clarify which PRRs and which Ad components are involved in Ad vector-induced innate immune responses. Our group previously demonstrated that myeloid differentiating factor 88 (MyD88) and toll-like receptor 9 (TLR9) play crucial roles in the Ad vector-induced inflammatory cytokine production in mouse bone marrow-derived dendritic cells. Furthermore, our group recently found that virus associated-RNAs (VA-RNAs), which are about 160 nucleotide-long non-coding small RNAs encoded in the Ad genome, are involved in IFN production through the IFN-β promoter stimulator-1 (IPS-1)-mediated signaling pathway following Ad vector transduction. The aim of this review is to highlight the Ad vector-induced innate immune responses following transduction, especially VA-RNA-mediated innate immune responses. Our findings on the mechanism of Ad vector-induced innate immune responses should make an important contribution to the development of safer Ad vectors, such as an Ad vector lacking expression of VA-RNAs.
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- 2011
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22. Generation of Brain Microvascular Endothelial-Like Cells from Human Induced Pluripotent Stem Cells by Co-Culture with C6 Glioma Cells.
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Haruka Minami, Katsuhisa Tashiro, Atsumasa Okada, Nobue Hirata, Tomoko Yamaguchi, Kazuo Takayama, Hiroyuki Mizuguchi, and Kenji Kawabata
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Medicine ,Science - Abstract
The blood brain barrier (BBB) is formed by brain microvascular endothelial cells (BMECs) and tightly regulates the transport of molecules from blood to neural tissues. In vitro BBB models from human pluripotent stem cell (PSCs)-derived BMECs would be useful not only for the research on the BBB development and function but also for drug-screening for neurological diseases. However, little is known about the differentiation of human PSCs to BMECs. In the present study, human induced PSCs (iPSCs) were differentiated into endothelial cells (ECs), and further maturated to BMECs. Interestingly, C6 rat glioma cell-conditioned medium (C6CM), in addition to C6 co-culture, induced the differentiation of human iPSC-derived ECs (iPS-ECs) to BMEC-like cells, increase in the trans-endothelial electrical resistance, decreased in the dextran transport and up-regulation of gene expression of tight junction molecules in human iPS-ECs. Moreover, Wnt inhibitors attenuated the effects of C6CM. In summary, we have established a simple protocol of the generation of BMEC-like cells from human iPSCs, and have demonstrated that differentiation of iPS-ECs to BMEC-like cells is induced by C6CM-derived signals, including canonical Wnt signals.
- Published
- 2015
- Full Text
- View/download PDF
23. Influence of Cocoa Flavanols and Procyanidins on Free Radical-induced Human Erythrocyte Hemolysis
- Author
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Carl L. Keen, Catherine L. Kwik-Uribe, Sun H. Kim, Tomoko Yamaguchi, Heidrun B. Gross, Roberta R. Holt, Qin Yan Zhu, and Derek D. Schramm
- Subjects
Immunologic diseases. Allergy ,RC581-607 - Published
- 2005
- Full Text
- View/download PDF
24. Hydropic leiomyoma-like ovarian tumor: a case report.
- Author
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Tomoko Yamaguchi, Hyo Kyozuka, Yoshihiro Kochi, Fumihiro Ito, Hajime Odajima, Daisuke Suzuki, and Yasuhisa Nomura
- Abstract
Uterine leiomyomas, benign tumors common in reproductive-aged women, can display rare variants such as hydropic leiomyoma (HL), which exhibit unique histological features like zonal edema and increased vascularity. However, due to its rarity, comprehensive clinical knowledge about HL is limited. We report a case of a 49-year-old Japanese woman who was premenopausal and nulliparous, presenting with a two-year history of abdominal distension. An MRI scan revealed a 20 cm mass in the posterior part of the uterus, exhibiting characteristics suggestive of an ovarian tumor. During laparotomy, a cystic tumor connected with a swollen fibroid was found, and pathology confirmed HL. This case emphasizes that hydropic leiomyomas can mimic malignant tumors on ultrasonography due to their atypical features, necessitating additional evaluations using alternative imaging techniques or histopathological examinations for accurate diagnosis and appropriate management. The patient recovered uneventfully, broadening our understanding of HL's clinical presentation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
25. In vitro validation of chromogenic substrate assay for evaluation of surrogate FVIII-activity of emicizumab
- Author
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Tomoko Yamaguchi, Keiko Shinozawa, Satoru Nagatoishi, Ayano Mitsuhashi, Masato Bingo, Hiroshi Inaba, Kagehiro Amano, Kohei Tsumoto, and Ei Kinai
- Subjects
Hematology - Published
- 2023
26. In vitro BBB model derived from human iPS cells
- Author
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Tomoko Yamaguchi and Kenji Kawabata
- Subjects
Pharmaceutical Science - Published
- 2023
27. 外科手術における暗黙知の理解と効率的な技能伝達支援システムの開発
- Author
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Tomoko Yamaguchi, Ken Masamune, and Yoshihiro Muragaki
- Subjects
General Medicine - Published
- 2023
28. Fetal heart rate patterns complicated by chorioamnionitis and subsequent cerebral palsy in Japan
- Author
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Tomoko Yamaguchi‐Goto, Masanao Ohashi, Yuki Kodama, and Hiroshi Sameshima
- Subjects
Obstetrics and Gynecology - Abstract
This retrospective study was performed to investigate whether certain fetal heart rate patterns were associated with subsequent cerebral palsy (CP) in infants with chorioamnionitis at or near term.We used cases registered by the Japan Obstetric Compensation System for CP, which is a nationwide population-based database. Among them, 133 infants with chorioamnionitis who were born at ≥34 weeks of gestation were enrolled. All infants underwent magnetic resonance imaging (MRI), and all fetal heart rate charts had been interpreted according to the National Institute of Child Health and Human Development criteria, focusing on antepartum and immediately before delivery.The incidence of CP after chorioamnionitis at ≥34 weeks of gestation was 0.3 per 10 000 in Japan. Between the clinical (24%) and subclinical groups (76%), the incidence of abnormal fetal heart rate patterns did not differ. According to the MRI classification, 88% of the infants with CP showed hypoxic-ischemic encephalopathy. Half of the infants with CP experienced terminal bradycardia, leading to severe acidosis and exclusively to hypoxic-ischemic encephalopathy. In another half, who did not experience bradycardia, 80% had moderate acidosis (pH 7.00-7.20) resulting in hypoxic-ischemic encephalopathy, and the remaining 20% showed non-acidosis resulting in brain damage other than hypoxic-ischemic encephalopathy. The fetal heart rate patterns before the terminal bradycardia showed that the incidence rates of late deceleration or decreased variability were high (60%).Fifty percent of pregnant women with chorioamnionitis-related CP had terminal bradycardia that exclusively resulted in hypoxic-ischemic encephalopathy.
- Published
- 2022
29. Characterization of novel antibodies that recognize sialylated keratan sulfate and lacto-N-fucopentaose I on human induced pluripotent cells: comparison with existing antibodies
- Author
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Hiromi Nakao, Tomoko Yamaguchi, Kenji Kawabata, Katsuaki Higashi, Motohiro Nonaka, Makoto Tuiji, Yuko Nagai, Hidenao Toyoda, Yoshiki Yamaguchi, Nobuko Kawasaki, and Toshisuke Kawasaki
- Subjects
Biochemistry - Abstract
In this study, we characterized a series of antibodies generated in C57BL/6 mice (Mus musculus) using the Tic (JCRB1331) human induced pluripotent cell (hiPSC) line as an antigen. This report describes the isolation and characterization of two new antibodies, R-6C (IgM) and R-13E (IgM), and their comparisons with two existing antibodies, R-10G (IgG1) and R-17F (IgG1). Their epitopes were studied by Western blotting after various glycosidase digestions, binding analyses using enzyme-linked immunosorbent assays (ELISAs) and microarrays with various synthetic oligosaccharides. The minimum epitope structures identified were: Siaα2-3Galβ1-3GlcNAc(6S)β1-3Galβ1-4GlcNAc(6S)β1 (R-6C), Fucα1-2Galβ1-3GlcNAcβ1-3Galβ1 (R-13E), Galβ1-4GlcNAc(6S)β1-3Galβ1-4GlcNAc(6S)β1 (R-10G), and Fucα1-2Galβ1-3GlcNAβ1-3Galβ1-4Glc (lacto-N-fucopentaose I) (R-17F) (shown in Fig. 11 using symbol nomenclature). Most glycoprotein epitopes are expressed as O-glycans on podocalyxin, a mucin-type glycoprotein. The common feature of these epitopes is the presence of an N-acetyllactosamine type 1 structure (Galβ1-3GlcNAc) at their nonreducing termini, followed by a type 2 structure (Galβ1-4GlcNAc); this arrangement comprises a type 1-type 2 motif. This motif is also shared by TRA-1-60, a traditional onco-fetal antigen. In contrast, the R-10G epitope has a type 2-type 2 motif. Among these antibodies, R-17F and R-13E exhibit cytotoxic activity toward hiPSCs. R-17F and R-13E exhibit extremely high similarity in the amino acid sequences in their complementarity-determining regions (CDRs), which is consistent with their highly similar glycan recognition. These antibodies are excellent tools for investigating the biological functions of glycoconjugates in hiPSCs/hESCs; they could be useful for the selection, isolation and selective killing of such undifferentiated pluripotent stem cells.
- Published
- 2022
30. Predicting postpartum hemorrhage in women undergoing planned cesarean section: a multicenter retrospective cohort study in Japan
- Author
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Tomoko Yamaguchi, Hyo Kyozuka, Momoka Ito, Tsuyoshi Hiraiwa, Tsuyoshi Murata, Misa Sugeno, Fumihiro Ito, Daisuke Suzuki, Toma Fukuda, Shun Yasuda, Fujimori Keiya, and Yasuhisa Nomura
- Abstract
Background Given Japan’s unique social background, it is critical to understand the current risk factors for postpartum hemorrhage (PPH) to effectively manage the condition, especially among specific groups. Therefore, this study aimed to clarify the current risk factors for blood loss during planned cesarean section (CS) in Japan.Methods This multicenter retrospective cohort study was conducted in two tertiary maternal-fetal medicine units in Fukushima, Japan and included 1,133 women who underwent planned CS between January 1, 2013, and December 31, 2022. Risk factors for PPH (of > 1000 g, > 1500 g, and > 2000 g) were assessed using multivariate logistic regression analysis, considering variables such as maternal age, parity, assisted reproductive technology (ART) pregnancy, pre-pregnancy body mass index (BMI), uterine myoma, placenta previa, gestational age at delivery, birth weight categories, and hypertensive disorders of pregnancy (HDP). Multivariate linear regression analyses were conducted to predict PPH risk during planned CS.Results ART pregnancy, pre-pregnancy BMI (25.0–29.9 kg/m2), placenta previa, and uterine myoma increased PPH risk at various levels. Maternal smoking increased the risk of > 2000 g PPH (adjusted odds ratio: 11.6, 95% confidence interval [CI]: 2.85–46.9). Multivariate linear analysis showed that advanced maternal age (B: 75 g; 95% CI: 21–128 g), ART pregnancy (B: 163 g; 95% CI: 50–275 g), pre-pregnancy BMI of 25.0 to 2 (B: 94 g; 95% CI: 22–167 g), uterine myoma (B: 189 g; 95% CI: 89–288 g), placenta previa (B: 558 g; 95% CI: 453–662 g), and birth weight > 3,500 g (B: 173 g; 95% CI: 44–303 g).Conclusions Considering a patient’s social background may help predict bleeding in planned CSs and help improve patient safety.
- Published
- 2023
31. Supplementary Figure Legends 1-2 from Protein Kinase Cδ Activates RelA/p65 and Nuclear Factor-κB Signaling in Response to Tumor Necrosis Factor-α
- Author
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Kiyotsugu Yoshida, Yoshio Miki, Tomoko Yamaguchi, Hanshao Liu, and Zheng-Guang Lu
- Abstract
Supplementary Figure Legends 1-2 from Protein Kinase Cδ Activates RelA/p65 and Nuclear Factor-κB Signaling in Response to Tumor Necrosis Factor-α
- Published
- 2023
32. Supplementary Figure 1 from Protein Kinase Cδ Activates RelA/p65 and Nuclear Factor-κB Signaling in Response to Tumor Necrosis Factor-α
- Author
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Kiyotsugu Yoshida, Yoshio Miki, Tomoko Yamaguchi, Hanshao Liu, and Zheng-Guang Lu
- Abstract
Supplementary Figure 1 from Protein Kinase Cδ Activates RelA/p65 and Nuclear Factor-κB Signaling in Response to Tumor Necrosis Factor-α
- Published
- 2023
33. Supplementary Figure 2 from Protein Kinase Cδ Activates RelA/p65 and Nuclear Factor-κB Signaling in Response to Tumor Necrosis Factor-α
- Author
-
Kiyotsugu Yoshida, Yoshio Miki, Tomoko Yamaguchi, Hanshao Liu, and Zheng-Guang Lu
- Abstract
Supplementary Figure 2 from Protein Kinase Cδ Activates RelA/p65 and Nuclear Factor-κB Signaling in Response to Tumor Necrosis Factor-α
- Published
- 2023
34. Stopped-flow-optical Absorption and -ESR Detection of Rutin (Quercetin-3-O-rutinoside) B-ring Catechol Aroxyl Radicals Generated during Redox Reaction between Rutin and O2−• Radical in DMSO
- Author
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Keiko Kuwabara, Natsuki Nishio, Ryota Nakano, Yasuhiro Sakurai, Tomoko Yamaguchi, Yusuke Miyake, Kenji Kanaori, and Kunihiko Tajima
- Subjects
General Chemistry - Published
- 2022
35. Transient ETV2 Expression Promotes the Generation of Mature Endothelial Cells from Human Pluripotent Stem Cells
- Author
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Hongyan, Zhang, Tomoko, Yamaguchi, Yasuhiro, Kokubu, and Kenji, Kawabata
- Subjects
Pharmacology ,Ischemia ,Induced Pluripotent Stem Cells ,Endothelial Cells ,Humans ,Pharmaceutical Science ,Cell Differentiation ,General Medicine ,Transcription Factors - Abstract
Differentiation protocols are used for induced pluripotent stem cells (iPSCs) in in vitro disease modeling and clinical applications. Transplantation of endothelial cells (ECs) is an important treatment strategy for ischemic diseases. For example, in vitro generated ECs can be used to provide the vascular plexus to regenerate organs such as the liver. Here, we demonstrate that the E-twenty-six (ETS) transcription factor ETV2 alone can directly convert iPSCs into vascular endothelial cells (iPS-ETV2-ECs) with an efficiency of over 90% within 5 d. Although the stable overexpression of ETV2 induced the expression of multiple key factors for endothelial development, the induced ECs were less mature. Furthermore, doxycycline-inducible transient ETV2 expression could upregulate the expression of von Willebrand factor (vWF) in iPS-ETV2-ECs, leading to a mature phenotype. The findings of this study on generation of mature iPS-ETV2-ECs provide further insights into the exploration of cell reprogramming from iPSCs. Here, we provide a new protocol for differentiation of iPSCs, thus providing a new source of ECs for in vitro disease modeling and clinical applications.
- Published
- 2022
36. Quality evaluation and postprandial glycemic response of gluten-free rice bread made from two types of rice flour with different amylose contents
- Author
-
Iana Korshunova, Tomoko Yamaguchi, Saori Kuremoto, and Yasuaki Enoki
- Subjects
Marketing ,General Chemical Engineering ,Industrial and Manufacturing Engineering ,Food Science ,Biotechnology - Published
- 2022
37. Current status of emicizumab using in clinical practice based on medical experience at Tokyo Medical University
- Author
-
Yushi CHIKASAWA, Tomoko YAMAGUCHI, and Kagehiro AMANO
- Published
- 2022
38. Real-World Use of Albutrepenonacog Alfa, A Recombinant Coagulation Factor IX Albumin Fusion Protein, for Personalized Prophylaxis in Japanese Individuals With Hemophilia B: A Case Series
- Author
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Azusa Nagao, Masato Bingo, Tomoko Yamaguchi, and Katsuyuki Fukutake
- Subjects
General Engineering - Published
- 2023
39. Purification and CryoEM Image Analysis of the Bacterial Flagellar Filament
- Author
-
Tomoko Yamaguchi, Tomoko Miyata, Fumiaki Makino, and Keiichi Namba
- Published
- 2023
40. Lead Optimization of Influenza Virus RNA Polymerase Inhibitors Targeting PA–PB1 Interaction
- Author
-
Satoshi Mizuta, Hiroki Otaki, Takeshi Ishikawa, Juliann Nzembi Makau, Tomoko Yamaguchi, Takuya Fujimoto, Nobuyuki Takakura, Nobuki Sakauchi, Shuji Kitamura, Hikaru Nono, Ryota Nishi, Yoshimasa Tanaka, Kohsuke Takeda, Noriyuki Nishida, and Ken Watanabe
- Subjects
Models, Molecular ,DNA-Directed RNA Polymerases ,Orthomyxoviridae ,Antiviral Agents ,Cell Line ,Madin Darby Canine Kidney Cells ,Molecular Docking Simulation ,Influenza B virus ,Structure-Activity Relationship ,Dogs ,Influenza A virus ,Drug Design ,Drug Discovery ,Animals ,Humans ,Molecular Medicine ,Enzyme Inhibitors - Abstract
Influenza viruses are responsible for contagious respiratory illnesses in humans and cause seasonal epidemics and occasional pandemics worldwide. Previously, we identified a quinolinone derivative
- Published
- 2021
41. Transport Characteristics of 6-Mercaptopurine in Brain Microvascular Endothelial Cells Derived From Human Induced Pluripotent Stem Cells
- Author
-
Katsuhisa Inoue, Tomoko Yamaguchi, Yoshiharu Deguchi, Kenji Kawabata, Tatsuki Mochizuki, Toshiki Kurosawa, Yuma Tega, Hiroyuki Kusuhara, Daiki Sako, and Naoki Ito
- Subjects
Induced Pluripotent Stem Cells ,Pharmaceutical Science ,ATP-binding cassette transporter ,02 engineering and technology ,Blood–brain barrier ,030226 pharmacology & pharmacy ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Humans ,Induced pluripotent stem cell ,Gene knockdown ,Mercaptopurine ,Chemistry ,Brain ,Endothelial Cells ,Biological Transport ,Transporter ,Membrane transport ,021001 nanoscience & nanotechnology ,Cell biology ,medicine.anatomical_structure ,Blood-Brain Barrier ,cardiovascular system ,0210 nano-technology ,Zaprinast ,medicine.drug - Abstract
The likelihood of reoccurrence of acute lymphoblastic leukemia is influenced by the cerebral concentration of the therapeutic agent 6-mercaptopurine (6-MP) during treatment. Therefore, it is important to understand the blood-brain barrier (BBB) transport mechanism of 6-MP. The purpose of this study was to characterize this mechanism using human induced pluripotent stem cell-derived microvascular endothelial cells (hiPS-BMECs). The permeability coefficient of 6-MP across hiPS-BMECs monolayer in the basal-to-apical direction (B-to-A) was significantly greater than that in the opposite direction (A-to-B). The inhibition profiles of 6-MP transport in the A-to-B direction were different from those in the B-to-A direction. Transport in the A-to-B direction was mainly inhibited by adenine (an inhibitor of equilibrative nucleobase transporter 1; ENBT1), while transport in the B-to-A direction was significantly reduced by inhibitors of multidrug resistance-associated proteins (MRPs), especially zaprinast (an MRP5 inhibitor). Immunocytochemical analyses demonstrated the expression of ENBT1 and MRP5 proteins in hiPS-BMECs. We confirmed that the cellular uptake of 6-MP is decreased by ENBT1 inhibitors in hiPS-BMECs and by knockdown of ENBT1 in hCMEC/D3 cells. These results suggest that ENBT1 and MRP5 make substantial contributions to the transport of 6-MP in hiPS-BMECs and hCMEC/D3 cells.
- Published
- 2021
42. Inhibition of Glycogen Synthase Kinase 3ß Enhances Functions of Induced Pluripotent Stem Cell-Derived Brain Microvascular Endothelial Cells in the Blood-Brain Barrier
- Author
-
Tomoko Yamaguchi, Misae Nishijima, and Kenji Kawabata
- Subjects
Pharmacology ,Blood-Brain Barrier ,Induced Pluripotent Stem Cells ,Glycogen Synthase Kinases ,Pharmaceutical Science ,Animals ,Brain ,Endothelial Cells ,Humans ,Cell Differentiation ,General Medicine ,ATP Binding Cassette Transporter, Subfamily B, Member 1 - Abstract
Brain microvascular endothelial cells (BMECs) are essential component of the blood-brain barrier (BBB). BMECs strictly regulate the entry of various molecules into the central nervous system from the peripheral circulation by forming tight junctions and expressing various influx/efflux transporters and receptors. In vitro BBB models have been widely reported with primary BMECs isolated from animals, although it is known that the expression patterns and levels of transporters and receptors in BMECs differ between humans and animals. Recently, several methods to differentiate BMECs from human induced pluripotent stem (hiPS) cell have been developed. However, the expression of P-glycoprotein (P-gp), which is a key efflux transporter, in hiPS cell-derived BMECs was detected at a relatively low level compared with primary human BMECs. In this study, we examined the involvement of the canonical Wnt signaling pathway, which contributes to the development of BBB formation, in the regulation of P-gp expression in hiPS cell-derived BMECs. We found that the barrier integrity was significantly enhanced in hiPS cell-derived BMECs treated with glycogen synthase kinase-3ß (GSK-3ß) inhibitors, which are known to positively regulate the canonical Wnt signaling pathway. In addition, our data also showed P-gp expression level was increased by treatment with GSK-3ß inhibitors. In conclusion, physiological barrier function and P-gp expression in BMECs can be enhanced by the canonical Wnt signaling pathway. Our results may be useful for promoting the development of drugs for central nervous system diseases using in vitro BBB model.
- Published
- 2022
43. Effect of cooking conditions on postprandial glycemic response and eating qualities of high-amylose rice 'Koshinokaori'
- Author
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Masumi Kobayashi, Makoto Mizutani, Shinobu Fujimura, Tomoko Yamaguchi, and Yasuaki Enoki
- Subjects
Marketing ,Postprandial ,business.industry ,General Chemical Engineering ,High amylose ,Medicine ,Food science ,business ,Industrial and Manufacturing Engineering ,Food Science ,Biotechnology ,Glycemic - Published
- 2021
44. Structures of multisubunit membrane complexes with the CRYO ARM 200
- Author
-
Christoph Gerle, Jun-ichi Kishikawa, Tomoko Yamaguchi, Atsuko Nakanishi, Orkun Çoruh, Fumiaki Makino, Tomoko Miyata, Akihiro Kawamoto, Ken Yokoyama, Keiichi Namba, Genji Kurisu, and Takayuki Kato
- Subjects
Lipopolysaccharides ,Vacuolar Proton-Translocating ATPases ,Photosystem I Protein Complex ,Structural Biology ,Cryoelectron Microscopy ,Radiology, Nuclear Medicine and imaging ,Peptidoglycan ,Instrumentation - Abstract
Progress in structural membrane biology has been significantly accelerated by the ongoing ‘Resolution Revolution’ in cryo-electron microscopy (cryo-EM). In particular, structure determination by single-particle analysis has evolved into the most powerful method for atomic model building of multisubunit membrane protein complexes. This has created an ever-increasing demand in cryo-EM machine time, which to satisfy is in need of new and affordable cryo-electron microscopes. Here, we review our experience in using the JEOL CRYO ARM 200 prototype for the structure determination by single-particle analysis of three different multisubunit membrane complexes: the Thermus thermophilus V-type ATPase VO complex, the Thermosynechococcus elongatus photosystem I monomer and the flagellar motor lipopolysaccharide peptidoglycan ring (LP ring) from Salmonella enterica.
- Published
- 2022
45. Development of Flow-Injection Spin-Trapping ESR Methods for Kinetic Study of the O2−•Radical Scavenging Reaction with Mixtures of Phenolic Antioxidants
- Author
-
Shuhei Yamaguchi, Naoto Yamamoto, Yasuhiro Sakurai, Tomoyuki Yamashita, Kenji Kanaori, Yao Lu, Tomoko Yamaguchi, Keiko Kuwabara, Yusuke Miyake, and Kunihiko Tajima
- Subjects
Phenolic antioxidant ,Spin trapping ,010405 organic chemistry ,General Chemistry ,010402 general chemistry ,Kinetic energy ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Reaction rate constant ,chemistry ,Superoxide radical ,Caffeic acid ,Scavenging - Abstract
The apparent second-order rate constants (aks) of the reaction between the O2−• radical and mixed solutions (aAox) of caffeic acid (CA) and 4-hydroxy-coumaric acid (4CA) were estimated in this stud...
- Published
- 2020
46. Design and Development of an HBT-Based Ratiometric Fluorescent Probe to Monitor Stress-Induced Premature Senescence
- Author
-
Kanami Kitamura, Tomoko Yamaguchi, Satoshi Mizuta, Juliann Nzembi Makau, and Ayako Kitagawa
- Subjects
chemistry.chemical_classification ,Reactive oxygen species ,Fluorophore ,biology ,General Chemical Engineering ,General Chemistry ,Stress-induced premature senescence ,biology.organism_classification ,medicine.disease_cause ,Fluorescence ,Article ,HeLa ,Chemistry ,chemistry.chemical_compound ,Benzothiazole ,chemistry ,Biophysics ,medicine ,QD1-999 ,Boronic acid ,Oxidative stress - Abstract
Stress-induced premature senescence (SIPS) can be induced in tumor cells by reactive oxygen species (ROS) or oncogenes. The antineoplastic drugs cause apoptosis and senescence by damaging the DNA. Although the detection of cellular senescence is important to monitor drug response during anticancer therapy, only a few probes have been studied for imaging SIPS. In this study, we developed 2-(2′-hydroxyphenyl)benzothiazole (HBT)-based fluorescent probes to determine SIPS by monitoring the oxidative stress and β-galactosidase activity. HBT is a commonly used fluorophore because of its luminescence mechanism via excited-state intramolecular proton transfer, and it has attractive properties, such as a four-level photochemical process and large Stokes shift (151 nm). A novel fluorescent probe, (2-(benzo[d]thiazol-2-yl)phenyl)boronic acid, was prepared for the detection of ROS, including H2O2, via the oxidation reaction of arylboronic acids to form the fluorescent phenol, HBT. In addition, to determine the enzymatic activity of β-galactosidase, a 2-(4′-chloro-2′-hydroxyphenyl)benzothiazole (CBT)-based enzymatic turn-on probe (CBT-β-Gal) was designed and synthesized. β-Galactosidase catalyzed the hydrolysis of β-galactopyranoside from CBT-β-Gal to release the fluorescent CBT. These probes were capable of ratiometric imaging the accumulation of H2O2 and the degree of β-galatosidase activity in contrast to H2O2-untreated and H2O2-treated HeLa cells. Furthermore, these probes were successfully employed for imaging the increased levels of ROS and β-galactosidase activity in the doxorubicin-treated HeLa cells.
- Published
- 2020
47. Stopped-flow-optical Absorption and -electron Spin Resonance Studies on Short-lived Quercetin Semiquinone Radical Produced by Redox Reactions with O2−• Radical in DMSO
- Author
-
Kenji Kanaori, Tomoko Yamaguchi, Ryota Nakano, Yasuhiro Sakurai, Keiko Kuwabara, Yusuke Miyake, and Kunihiko Tajima
- Subjects
Semiquinone anion ,Semiquinone ,General Chemistry ,Stopped flow ,Photochemistry ,Redox ,law.invention ,Esr spectra ,chemistry.chemical_compound ,chemistry ,law ,Absorption (chemistry) ,Electron paramagnetic resonance ,Quercetin - Abstract
The stopped-flow-optical absorption and -ESR spectra of a quercetin (QueH2) derived semiquinone anion radical (Que−•, half-life time ∼31 ms) were detected by mixing the O2−• radical and QueH2 in di...
- Published
- 2020
48. Transcriptomic Dissection of Hepatocyte Heterogeneity: Linking Ploidy, Zonation, and Stem/Progenitor Cell CharacteristicsSummary
- Author
-
Tomoko Yamaguchi, Atsunori Tsuchiya, Kazunori Hosaka, Takahiro Ochiya, Takeshi Katsuda, Shuji Terai, Juntaro Matsuzaki, Marta Prieto-Vila, and Wataru Usuba
- Subjects
0301 basic medicine ,Cell division ,Cell ,Primary Cell Culture ,Context (language use) ,Biology ,Transcriptome ,Polyploidy ,03 medical and health sciences ,Genetic Heterogeneity ,0302 clinical medicine ,medicine ,Animals ,Progenitor cell ,lcsh:RC799-869 ,Cells, Cultured ,Progenitor ,Cell Proliferation ,Oligonucleotide Array Sequence Analysis ,Hepatology ,Microarray analysis techniques ,Gene Expression Profiling ,Stem Cells ,Gastroenterology ,Cell biology ,Rats ,030104 developmental biology ,medicine.anatomical_structure ,Editorial ,Liver ,Hepatocyte ,Hepatocytes ,030211 gastroenterology & hepatology ,lcsh:Diseases of the digestive system. Gastroenterology ,Single-Cell Analysis - Abstract
Background & Aims: There is a long-standing debate regarding the biological significance of polyploidy in hepatocytes. Recent studies have provided increasing evidence that hepatocytes with different ploidy statuses behave differently in a context-dependent manner (eg, susceptibility to oncogenesis, regenerative ability after injury, and in vitro proliferative capacity). However, their overall transcriptomic differences in a physiological context is not known. Methods: By using microarray transcriptome analysis, we investigated the heterogeneity of hepatocyte populations with different ploidy statuses. Moreover, by using single-cell quantitative reverse-transcription polymerase chain reaction (scPCR) analysis, we investigated the intrapopulational transcriptome heterogeneity of 2c and 4c hepatocytes. Results: Microarray analysis showed that cell cycle–related genes were enriched in 8c hepatocytes, which is in line with the established notion that polyploidy is formed via cell division failure. Surprisingly, in contrast to the general consensus that 2c hepatocytes reside in the periportal region, in our bulk transcriptome and scPCR analyses, the 2c hepatocytes consistently showed pericentral hepatocyte-enriched characteristics. In addition, scPCR analysis identified a subpopulation within the 2c hepatocytes that co-express the liver progenitor cell markers Axin2, Prom1, and Lgr5, implying the potential biological relevance of this subpopulation. Conclusions: This study provides new insights into hepatocyte heterogeneity, namely 2c hepatocytes are preferentially localized to the pericentral region, and a subpopulation of 2c hepatocytes show liver progenitor cell–like features in terms of liver progenitor cell marker expression (Axin2, Prom1, and Lgr5). Keywords: Hepatocyte, Ploidy, Zonation, Single-Cell PCR, Transcriptome
- Published
- 2020
49. Skill Assessment and Visualization System for Endoscopic Sinus Surgery : a Clinical Study
- Author
-
Ryoichi Nakamura, Nobuyoshi Otori, Tomoko Yamaguchi, Akihito Kuboki, Yuichiro Sawano, and Ryu Ebata
- Subjects
Clinical study ,Computer-assisted surgery ,medicine.medical_specialty ,Endoscopic sinus surgery ,business.industry ,medicine.medical_treatment ,medicine ,Radiology ,business ,Visualization - Published
- 2020
50. Construction of brain area risk map for decision making using surgical navigation and motor evoked potential monitoring information
- Author
-
Tomoko Yamaguchi, Atsushi Kuwano, Toshihiko Koyama, Jun Okamoto, Shigeyuki Suzuki, Hideki Okuda, Taiichi Saito, Ken Masamune, and Yoshihiro Muragaki
- Subjects
Biomedical Engineering ,Health Informatics ,Radiology, Nuclear Medicine and imaging ,Surgery ,General Medicine ,Computer Vision and Pattern Recognition ,Computer Graphics and Computer-Aided Design ,Computer Science Applications - Abstract
Surgical devices or systems typically operate in a stand-alone manner, making it difficult to perform integration analysis of both intraoperative anatomical and functional information. To address this issue, the intraoperative information integration system OPeLiNKWe accumulated intraoperative information from 27 brain tumor patients who underwent resection surgery. First, the risk rank for postoperative paralysis was set according to the attenuation rate and amplitude width of the motor evoked potential (MEP). Then, the MEP and navigation log data were combined and plotted on an intraoperative magnetic resonance image of the individual brain. Finally, statistical parametric mapping (SPM) transformation was performed to generate a standard brain risk map of postoperative paralysis. Additionally, we determined the anatomical high-risk areas using atlases and analyzed the relationship with each set risk rank.The average distance between the navigation log corresponding to each MEP risk rank and the anatomical high-risk area differed significantly between the with postoperatively paralyzed and without postoperatively paralyzed groups, except for "safe." Furthermore, no excessive deformation was observed resulting from SPM conversion to create the standard brain risk map. There were cases in which no postoperative paralysis occurred even when MEP decreased intraoperatively, and vice versa.The time synchronization reliability of the study data is very high. Therefore, our created risk map can be reported as being functional at indicating the risk areas. Our results suggest that the statistical risks of postoperative complications can be presented for each area where brain surgery is to be performed. In the future, it will be possible to provide surgical navigation with intraoperative support that reflects the risk maps created.
- Published
- 2022
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