47 results on '"Y. Fujiwara"'
Search Results
2. Effect of nutritional status on occurrence of pneumonia after traumatic cervical spinal cord injury.
- Author
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Hayashi T, Fujiwara Y, Irie M, Masuda M, Sakai H, Kobayashi H, Kawano O, and Maeda T
- Subjects
- Humans, Male, Female, Middle Aged, Adult, Retrospective Studies, Risk Factors, Aged, Cervical Cord injuries, Spinal Cord Injuries complications, Nutritional Status, Pneumonia etiology
- Abstract
Pneumonia after cervical spinal cord injury (CSCI) is a common and serious complication; however, its nutrition-related etiology has not yet been elucidated. This study aimed to elucidate the effects of nutritional factors on pneumonia after CSCI. Patients with acute traumatic CSCI who were admitted within 3 days after injury and followed up for at least 3 months were retrospectively examined. Occurrence of pneumonia, nutritional status, severity of dysphagia, vital capacity, use of respirators, and motor scores for paralysis were evaluated. Of 182 patients included in this study, 33 (18%) developed pneumonia. Multiple logistic regression analysis revealed that low nutritional status, severe paralysis, and low vital capacity were significant risk factors for pneumonia. The severity of paralysis, respiratory dysfunction, and poor nutritional status can affect the occurrence of pneumonia after CSCI. In addition to respiratory management, nutritional assessment and intervention may play key roles in preventing pneumonia associated with spinal cord injury-induced immune depression. Nutritional care should be provided as soon as possible when the nutritional status of a patient worsens after an injury., (© 2024. The Author(s).)
- Published
- 2024
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3. Exosomal miR-493 suppresses MAD2L1 and induces chemoresistance to intraperitoneal paclitaxel therapy in gastric cancer patients with peritoneal metastasis.
- Author
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Makinoya M, Miyatani K, Matsumi Y, Sakano Y, Shimizu S, Shishido Y, Hanaki T, Kihara K, Matsunaga T, Yamamoto M, Tokuyasu N, Takano S, Sakamoto T, Hasegawa T, Saito H, Nakayama Y, Osaki M, Okada F, and Fujiwara Y
- Subjects
- Humans, Cell Line, Tumor, Male, Female, Middle Aged, Aged, Antineoplastic Agents, Phytogenic pharmacology, Antineoplastic Agents, Phytogenic therapeutic use, Antineoplastic Agents, Phytogenic administration & dosage, MicroRNAs genetics, MicroRNAs metabolism, Stomach Neoplasms drug therapy, Stomach Neoplasms genetics, Stomach Neoplasms pathology, Stomach Neoplasms metabolism, Paclitaxel pharmacology, Paclitaxel therapeutic use, Paclitaxel administration & dosage, Drug Resistance, Neoplasm genetics, Exosomes metabolism, Exosomes genetics, Peritoneal Neoplasms secondary, Peritoneal Neoplasms drug therapy, Peritoneal Neoplasms genetics, Peritoneal Neoplasms metabolism, Mad2 Proteins metabolism, Mad2 Proteins genetics, Gene Expression Regulation, Neoplastic drug effects
- Abstract
Intraperitoneal (IP) chemotherapy with paclitaxel (PTX) for gastric cancer (GC) with peritoneal metastasis (PM) is considered a promising treatment approach, however, there are no useful biomarkers to predict the efficacy of IP therapy. We examined the association between intra-peritoneal exosomes, particularly exosomal micro-RNAs (exo-miRNAs), and IP-chemo sensitivity. MKN45 cells that were cultured with intra-peritoneal exosomes from patients who did not respond to IP therapy with PTX (IP
non-respond group) exhibited resistance to PTX compared with exosomes from responding patients (IPrespond group) (p = 0.002). A comprehensive search for exo-miRNAs indicated that miR-493 was significantly up-regulated in exosomes from the IPnon-respond group compared with those collected from the IPrespond group. The expression of miR-493 in PTX-resistant MKN45 cells (MKN45PTX-res ) was higher compared with that in MKN45. In addition, MKN45PTX-res cells exhibited lower MAD2L1 gene and protein expression compared with MKN45. Finally, miR-493 enhancement by transfection of miR-493 mimics significantly down-regulated MAD2L1 expression in MKN45 cells and reduced PTX sensitivity. Our results suggest that intra-peritoneal exo-miR-493 is involved in chemoresistance to PTX by downregulating MAD2L1 in GC with PM. Exo-miR-493 may be a biomarker for chemoresistance and prognosis of GC patients with PM and may also be a promising therapeutic target., (© 2024. The Author(s).)- Published
- 2024
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4. Ceramide synthase CERS4 gene downregulation is associated with KRAS mutation in colorectal cancer.
- Author
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Hayama T, Hama K, Ozawa T, Fujiwara Y, Nozawa K, Matsuda K, Yokoyama K, Hashiguchi Y, Ochiai H, Misawa T, and Fukagawa T
- Subjects
- Humans, Down-Regulation, Sphingolipids metabolism, Mutation, Proto-Oncogene Proteins p21(ras) genetics, Proto-Oncogene Proteins p21(ras) metabolism, Colorectal Neoplasms pathology
- Abstract
Ceramide, the central molecule in sphingolipid synthesis, is a bioactive lipid that serves as a regulatory molecule in the anti-inflammatory responses, apoptosis, programmed necrosis, autophagy, and cell motility of cancer cells. In particular, the authors have reported differences in sphingolipid content in colorectal cancer tissues. The associations among genetic mutations, clinicopathological factors, and sphingolipid metabolism in colorectal cancer (CRC) have not been investigated. The objective of this study is to investigate the association between genes associated with sphingolipid metabolism, genetic variations in colorectal cancer (CRC), and clinicopathological factors in CRC patients. We enrolled 82 consecutive patients with stage I-IV CRC who underwent tumor resection at a single institution in 2019-2021. We measured the expression levels of genes related to sphingolipid metabolism and examined the relationships between CRC gene mutations and the clinicopathological data of each individual patient. The relationship between CRC gene mutations and expression levels of ceramide synthase (CERS), N-acylsphingosine amidohydrolase (ASAH), and alkaline ceramidase (ACER) genes involved in sphingolipid metabolism was examined CRES4 expression was significantly lower in the CRC KRAS gene mutation group (p = 0.004); vascular invasion was more common in colorectal cancer patients with high CERS4 expression (p = 0.0057). By examining the correlation between sphingolipid gene expression and clinical factors, we were able to identify cancer types in which sphingolipid metabolism is particularly relevant. CERS4 expression was significantly reduced in KRAS mutant CRC. Moreover, CRC with decreased CERS4 showed significantly more frequent venous invasion., (© 2023. Springer Nature Limited.)
- Published
- 2023
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5. Lymphocyte-to-monocyte ratio as a prognostic and potential tumor microenvironment indicator in advanced soft tissue sarcoma treated with first-line doxorubicin therapy.
- Author
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Watanabe S, Shimoi T, Nishikawa T, Kawachi A, Okuma HS, Tokura M, Yazaki S, Mizoguchi C, Arakaki M, Saito A, Kita S, Yamamoto K, Kojima Y, Sudo K, Noguchi E, Yoshida A, Kawai A, Fujiwara Y, and Yonemori K
- Subjects
- Humans, Prognosis, Monocytes, Tumor Microenvironment, Lymphocytes, Doxorubicin therapeutic use, Retrospective Studies, Soft Tissue Neoplasms pathology, Sarcoma pathology
- Abstract
Prognostic value of hematologic indices and their association with the tumor microenvironment (TME) remain unclear in advanced soft tissue sarcoma (STS). We aimed to evaluate their prognostic value and correlation with the TME status in advanced STS treated with first-line doxorubicin (DXR) therapy. Clinical data and three hematological indices, including lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio, and neutrophil-to-lymphocyte ratio, were collected from 149 patients with advanced STS. The TME status was pathologically examined by CD3, CD68, and CD20 staining of resected tumor slides. In a multivariate Cox analysis, low LMR and absence of primary tumor resection were independently associated with worse overall survival (OS) (HR 3.93, p = 0.001; HR 1.71, p = 0.03). A prognostic model using these variables predicted OS with greater area under curves than those obtained using Systemic Inflammatory Score and Glasgow Prognostic Score. The LMR significantly correlated with the tumoral CD3/CD68-positive cell ratio in surgical specimens (R = 0.959, p = 0.04). In conclusion, LMR was a prognostic factor in advanced STS treated with first-line DXR therapy. LMR could partially reflect anti-tumor immunity in the TME and have the prognostic value. The potential role of LMR as an indicator of TME status warrants further investigation., (© 2023. The Author(s).)
- Published
- 2023
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6. Association of social disengagement with health status and all-cause mortality among community-dwelling older adults: evidence from the Otassha study.
- Author
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Ejiri M, Kawai H, Ito K, Hirano H, Fujiwara Y, Ihara K, Kim H, and Obuchi S
- Subjects
- Humans, Aged, Longitudinal Studies, Surveys and Questionnaires, Japan epidemiology, Independent Living, Health Status
- Abstract
This study examined the impact of disengagement on health status and mortality among community-dwelling older adults in Japan. Disengagement from society was operationally defined as dropping out of a longitudinal survey. A follow-up mail survey was conducted, in 2014, among respondents (n = 3696) of the baseline mail survey. Step-by-step follow-up surveys (FLs), including simplified mail, postcard, and home-visit surveys, were sent to participants who did not respond. Disengagement levels were defined according to the response to the FLs as zero (mail survey), low (simplified mail survey), middle (postcard survey), high (home-visit survey), and highest (non-responders to the home-visit survey). After adjusting for health status at baseline, the proportion of respondents self-rated as "not healthy" during FLs was significantly higher in the high-level than in the zero-level group. The proportion of respondents reporting a "once a week or less" frequency of going outdoors during FLs was significantly higher in the low-, middle-, and high-level groups than in the zero-level group. Mortality rates were significantly higher in the high and highest levels than in the zero-level group. Higher disengagement levels increased the risk of lower health status and mortality, suggesting an urgent need to prevent societal disengagement among older adults., (© 2022. The Author(s).)
- Published
- 2022
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7. GM-CSF derived from the inflammatory microenvironment potentially enhanced PD-L1 expression on tumor-associated macrophages in human breast cancer.
- Author
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Yonemitsu K, Pan C, Fujiwara Y, Miyasato Y, Shiota T, Yano H, Hosaka S, Tamada K, Yamamoto Y, and Komohara Y
- Subjects
- Animals, B7-H1 Antigen, Female, Humans, Ligands, Mice, Mice, Nude, Tumor Microenvironment, Tumor-Associated Macrophages, Breast Neoplasms, Granulocyte-Macrophage Colony-Stimulating Factor
- Abstract
Ever since immune checkpoint inhibitors have been approved for anti-cancer therapy in several cancers, including triple-negative breast cancer, the significance of programmed death-1 ligand 1 (PD-L1) expression in the tumor immune microenvironment has been a topic of interest. In the present study, we investigated the detailed mechanisms of PD-L1 overexpression on tumor-associated macrophages (TAMs) in breast cancer. In in vitro culture studies using human monocyte-derived macrophages, lymphocytes, and breast cancer cell lines, PD-L1 overexpression on macrophages was induced by the conditioned medium (CM) of activated lymphocytes, but not that of cancer cells. Granulocyte-macrophage colony-stimulating factor (GM-CSF) derived from activated lymphocytes was found to be involved in PD-L1 overexpression, in addition to interferon (IFN)-γ, via STAT3 pathway activation. Macrophages suppressed lymphocyte activation, and this inhibition was impaired by PD-1 blocking. The CM of activated lymphocytes also induced the overexpression of PD-L2, but GM-CSF did not affect PD-L2 expression. In the murine E0771 breast cancer model, anti-GM-CSF therapy did not affect PD-L1 expression on TAMs, and the mechanisms of PD-L1 expression on TAMs might differ between humans and mice. However, not only PD-L1, but also PD-L2 was overexpressed on TAMs in the E0771 tumor model, and their expression levels were significantly lower in the tumors in nude mice than in wild-type mice. Anti-PD-L1 antibody and anti-PD-L2 antibody synergistically inhibited E0771 tumor development. In conclusion, PD-L1 and PD-L2 were overexpressed on TAMs, and they potentially contributed to immunosuppression. The GM-CSF-STAT3 pathway is thought to represent a new mechanism of PD-L1 overexpression on TAMs in human breast cancer microenvironment., (© 2022. The Author(s).)
- Published
- 2022
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8. Unplanned hemodialysis initiation and low geriatric nutritional risk index scores are associated with end-stage renal disease outcomes.
- Author
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Maenosono R, Fukushima T, Kobayashi D, Matsunaga T, Yano Y, Taniguchi S, Fujiwara Y, Komura K, Uehara H, Kagitani M, Hirano H, Inamoto T, Nomi H, and Azuma H
- Subjects
- Aged, Geriatric Assessment, Humans, Nutrition Assessment, Nutritional Status, Renal Dialysis, Risk Factors, Kidney Failure, Chronic complications, Malnutrition complications
- Abstract
Patients with end-stage renal disease (ESRD) have a low nutritional status and a high mortality risk. The geriatric nutritional risk index (GNRI) is a predictive marker of malnutrition. However, the association between unplanned hemodialysis (HD) and GNRI with mortality remains unclear. In total, 162 patients underwent HD at our hospital. They were divided into two groups: those with unplanned initiation with a central venous catheter (CVC; n = 62) and those with planned initiation with prepared vascular access (n = 100). There were no significant differences in sex, age, malignant tumor, hypertension, and vascular disease, while there were significant differences in the times from the first visit to HD initiation (zero vs. six times, p < 0.001) and days between the first visit and HD initiation (5 vs. 175 days, p < 0.001). The CVC insertion group had significantly lower GNRI scores at initiation (85.7 vs. 99.0, p < 0.001). The adjusted hazard ratios were 4.002 and 3.018 for the GNRI scores and frequency, respectively. The 3-year survival rate was significantly lower in the CVC + low GNRI group (p < 0.0001). The GNRI after 1 month was significantly inferior in the CVC insertion group. Inadequate general management due to late referral to the nephrology department is a risk factor for patients with ESRD., (© 2022. The Author(s).)
- Published
- 2022
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9. Human chromosome 3p21.3 carries TERT transcriptional regulators in pancreatic cancer.
- Author
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Yagyu T, Ohira T, Shimizu R, Morimoto M, Murakami Y, Hanaki T, Kihara K, Matsunaga T, Yamamoto M, Tokuyasu N, Sakamoto T, Fujiwara Y, and Kugoh H
- Subjects
- Animals, Carcinogenesis metabolism, Carcinogenesis pathology, Cell Line, Tumor, Cell Proliferation, Chromosomes, Human, Pair 3 metabolism, Gene Expression Regulation, Neoplastic, Humans, Mice, Neoplasm Invasiveness, Pancreatic Neoplasms metabolism, Pancreatic Neoplasms pathology, Promoter Regions, Genetic, Telomerase metabolism, Transcription, Genetic, Carcinogenesis genetics, Chimera genetics, Chromosomes, Human, Pair 3 chemistry, Loss of Heterozygosity, Pancreatic Neoplasms genetics, Telomerase genetics
- Abstract
Frequent loss of heterozygosity (LOH) on the short arm of human chromosome 3 (3p) region has been found in pancreatic cancer (PC), which suggests the likely presence of tumor suppressor genes in this region. However, the functional significance of LOH in this region in the development of PC has not been clearly defined. The human telomerase reverse transcriptase gene (hTERT) contributes to unlimited proliferative and tumorigenicity of malignant tumors. We previously demonstrated that hTERT expression was suppressed by the introduction of human chromosome 3 in several cancer cell lines. To examine the functional role of putative TERT suppressor genes on chromosome 3 in PC, we introduced an intact human chromosome 3 into the human PK9 and murine LTPA PC cell lines using microcell-mediated chromosome transfer. PK9 microcell hybrids with an introduced human chromosome 3 showed significant morphological changes and rapid growth arrest. Intriguingly, microcell hybrid clones of LTPA cells with an introduced human chromosome 3 (LTPA#3) showed suppression of mTert transcription, cell proliferation, and invasion compared with LTPA#4 cells containing human chromosome 4 and parental LTPA cells. Additionally, the promoter activity of mTert was downregulated in LTPA#3. Furthermore, we confirmed that TERT regulatory gene(s) are present in the 3p21.3 region by transfer of truncated chromosomes at arbitrary regions. These results provide important information on the functional significance of the LOH at 3p for development and progression of PC., (© 2021. The Author(s).)
- Published
- 2021
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10. Elevated cellular PpIX potentiates sonodynamic therapy in a mouse glioma stem cell-bearing glioma model by downregulating the Akt/NF-κB/MDR1 pathway.
- Author
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Shono K, Mizobuchi Y, Yamaguchi I, Nakajima K, Fujiwara Y, Fujihara T, Kitazato K, Matsuzaki K, Uto Y, Sampetrean O, Saya H, and Takagi Y
- Subjects
- Aminolevulinic Acid pharmacology, Animals, Cell Line, Tumor, Down-Regulation drug effects, Down-Regulation physiology, Glioblastoma metabolism, Male, Mice, Mice, Inbred C57BL, Neoplastic Stem Cells drug effects, Photosensitizing Agents pharmacology, Signal Transduction drug effects, Signal Transduction genetics, Ultrasonic Therapy methods, ATP Binding Cassette Transporter, Subfamily B, Member 1 metabolism, Glioma metabolism, NF-kappa B metabolism, Neoplastic Stem Cells metabolism, Proto-Oncogene Proteins c-akt metabolism, Protoporphyrins metabolism
- Abstract
Glioblastoma (GBM) has high mortality rates because of extreme therapeutic resistance. During surgical resection for GBM, 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is conventionally applied to distinguish GBM. However, surgical intervention is insufficient for high invasive GBM. Sonodynamic therapy (SDT) combined with low-intensity ultrasonication (US) and PpIX, as a sonosensitizer, is an emerging and promising approach, although its efficacy is limited. Based on our previous study that down-regulation of multidrug resistant protein (MDR1) in GBM augmented the anti-tumor effects of chemotherapy, we hypothesized that elevation of cellular PpIX levels by down-regulation of MDR1 enhances anti-tumor effects by SDT. In high invasive progeny cells from mouse glioma stem cells (GSCs) and a GSC-bearing mouse glioma model, we assessed the anti-tumor effects of SDT with a COX-2 inhibitor, celecoxib. Down-regulation of MDR1 by celecoxib increased cellular PpIX levels, as well as valspodar, an MDR1 inhibitor, and augmented anti-tumor effects of SDT. MDR1 down-regulation via the Akt/NF-κB pathway by celecoxib was confirmed, using an NF-κB inhibitor, CAPÉ. Thus, elevation of cellar PpIX by down-regulation of MDR1 via the Akt/NF-κB pathway may be crucial to potentiate the efficacy of SDT in a site-directed manner and provide a promising new therapeutic strategy for GBM., (© 2021. The Author(s).)
- Published
- 2021
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11. Colonization of distant organs by tumor cells generating circulating homotypic clusters adaptive to fluid shear stress.
- Author
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Maeshiro M, Shinriki S, Liu R, Nakachi Y, Komohara Y, Fujiwara Y, Ohtsubo K, Yoshida R, Iwamoto K, Nakayama H, and Matsui H
- Subjects
- Animals, Cell Line, Humans, Mice, Head and Neck Neoplasms pathology, Neoplasm Metastasis pathology, Neoplastic Cells, Circulating pathology, Squamous Cell Carcinoma of Head and Neck pathology
- Abstract
Once disseminated tumor cells (DTCs) arrive at a metastatic organ, they remain there, latent, and become seeds of metastasis. However, the clonal composition of DTCs in a latent state remains unclear. Here, we applied high-resolution DNA barcode tracking to a mouse model that recapitulated the metastatic dormancy of head and neck squamous cell carcinoma (HNSCC). We found that clones abundantly circulated peripheral blood dominated DTCs. Through analyses of multiple barcoded clonal lines, we identified specific subclonal population that preferentially generated homotypic circulating tumor cell (CTC) clusters and dominated DTCs. Despite no notable features under static conditions, this population significantly generated stable cell aggregates that were resistant to anoikis under fluid shear stress (FSS) conditions in an E-cadherin-dependent manner. Our data from various cancer cell lines indicated that the ability of aggregate-constituting cells to regulate cortical actin-myosin dynamics governed the aggregates' stability in FSS. The CTC cluster-originating cells were characterized by the expression of a subset of E-cadherin binding factors enriched with actin cytoskeleton regulators. Furthermore, this expression signature was associated with locoregional and metastatic recurrence in HNSCC patients. These results reveal a biological selection of tumor cells capable of generating FSS-adaptive CTC clusters, which leads to distant colonization.
- Published
- 2021
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12. Very long-chain fatty acids are accumulated in triacylglycerol and nonesterified forms in colorectal cancer tissues.
- Author
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Hama K, Fujiwara Y, Hayama T, Ozawa T, Nozawa K, Matsuda K, Hashiguchi Y, and Yokoyama K
- Subjects
- HCT116 Cells, HEK293 Cells, Humans, Lipid Metabolism, Colorectal Neoplasms metabolism, Fatty Acid Elongases metabolism, Fatty Acids, Nonesterified metabolism, Triglycerides metabolism
- Abstract
Colorectal cancer (CRC) is a major cancer, and its precise diagnosis is especially important for the development of effective therapeutics. In a series of metabolome analyses, the levels of very long chain fatty acids (VLCFA) were shown to be elevated in CRC tissues, although the endogenous form of VLCFA has not been fully elucidated. In this study we analyzed the amount of nonesterified fatty acids, acyl-CoA species, phospholipids and neutral lipids such as cholesterylesters using liquid-chromatography-mass spectrometry. Here we showed that VLCFA were accumulated in triacylglycerol (TAG) and nonesterified forms in CRC tissues. The levels of TAG species harboring a VLCFA moiety (VLCFA-TAG) were significantly correlated with that of nonesterified VLCFA. We also showed that the expression level of elongation of very long-chain fatty acids protein 1 (ELOVL1) is increased in CRC tissues, and the inhibition of ELOVL1 decreased the levels of VLCFA-TAG and nonesterified VLCFA in CRC cell lines. Our results suggest that the upregulation of ELOVL1 contributes to the accumulation of VLCFA-TAG and nonesterified VLCFA in CRC tissues.
- Published
- 2021
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13. Discovery of a colossal slickhead (Alepocephaliformes: Alepocephalidae): an active-swimming top predator in the deep waters of Suruga Bay, Japan.
- Author
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Fujiwara Y, Kawato M, Poulsen JY, Ida H, Chikaraishi Y, Ohkouchi N, Oguri K, Gotoh S, Ozawa G, Tanaka S, Miya M, Sado T, Kimoto K, Toyofuku T, and Tsuchida S
- Subjects
- Amino Acids metabolism, Animals, Geography, Isotope Labeling, Japan, Perciformes anatomy & histology, Phylogeny, Stomach, Bays, Perciformes physiology, Predatory Behavior physiology, Swimming physiology
- Abstract
A novel species of the family Alepocephalidae (slickheads), Narcetes shonanmaruae, is described based on four specimens collected at depths greater than 2171 m in Suruga Bay, Japan. Compared to other alepocephalids, this species is colossal (reaching ca. 140 cm in total length and 25 kg in body weight) and possesses a unique combination of morphological characters comprising anal fin entirely behind the dorsal fin, multiserial teeth on jaws, more scale rows than congeners, precaudal vertebrae less than 30, seven branchiostegal rays, two epurals, and head smaller than those of relatives. Mitogenomic analyses also support the novelty of this large deep-sea slickhead. Although most slickheads are benthopelagic or mesopelagic feeders of gelatinous zooplankton, behavioural observations and dietary analyses indicate that the new species is piscivorous. In addition, a stable nitrogen isotope analysis of specific amino acids showed that N. shonanmaruae occupies one of the highest trophic positions reported from marine environments to date. Video footage recorded using a baited camera deployed at a depth of 2572 m in Suruga Bay revealed the active swimming behaviour of this slickhead. The scavenging ability and broad gape of N. shonanmaruae might be correlated with its colossal body size and relatively high trophic position.
- Published
- 2021
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14. Establishment of a heart-on-a-chip microdevice based on human iPS cells for the evaluation of human heart tissue function.
- Author
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Abulaiti M, Yalikun Y, Murata K, Sato A, Sami MM, Sasaki Y, Fujiwara Y, Minatoya K, Shiba Y, Tanaka Y, and Masumoto H
- Subjects
- Adrenergic beta-Agonists pharmacology, Electric Stimulation, Heart Rate drug effects, Humans, Induced Pluripotent Stem Cells drug effects, Isoproterenol pharmacology, Myocardial Contraction drug effects, Myocytes, Cardiac drug effects, Induced Pluripotent Stem Cells physiology, Lab-On-A-Chip Devices, Myocytes, Cardiac physiology
- Abstract
Human iPS cell (iPSC)-derived cardiomyocytes (CMs) hold promise for drug discovery for heart diseases and cardiac toxicity tests. To utilize human iPSC-derived CMs, the establishment of three-dimensional (3D) heart tissues from iPSC-derived CMs and other heart cells, and a sensitive bioassay system to depict physiological heart function are anticipated. We have developed a heart-on-a-chip microdevice (HMD) as a novel system consisting of dynamic culture-based 3D cardiac microtissues derived from human iPSCs and microelectromechanical system (MEMS)-based microfluidic chips. The HMDs could visualize the kinetics of cardiac microtissue pulsations by monitoring particle displacement, which enabled us to quantify the physiological parameters, including fluidic output, pressure, and force. The HMDs demonstrated a strong correlation between particle displacement and the frequency of external electrical stimulation. The transition patterns were validated by a previously reported versatile video-based system to evaluate contractile function. The patterns are also consistent with oscillations of intracellular calcium ion concentration of CMs, which is a fundamental biological component of CM contraction. The HMDs showed a pharmacological response to isoproterenol, a β-adrenoceptor agonist, that resulted in a strong correlation between beating rate and particle displacement. Thus, we have validated the basic performance of HMDs as a resource for human iPSC-based pharmacological investigations.
- Published
- 2020
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15. Continued smoking and posterior vitreous adhesion in the elderly evaluated on swept-source optical coherence tomography.
- Author
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Toyama T, Hashimoto Y, Kawai H, Azuma K, Shiraya T, Araki F, Sugimoto K, Watanabe Y, Hirano H, Fujiwara Y, Ihara K, Kim H, Kato S, Numaga J, Obuchi S, and Ueta T
- Subjects
- Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Humans, Male, Smoking adverse effects, Smoking physiopathology, Tomography, Optical Coherence, Vitreous Body diagnostic imaging, Vitreous Body physiopathology, Vitreous Detachment diagnostic imaging, Vitreous Detachment etiology, Vitreous Detachment physiopathology
- Abstract
In this cross-sectional study including 1150 eyes of 681 volunteers ≧ 65 years old without retinal pathology, factors affecting the progression of posterior vitreous detachment (PVD) were investigated. PVD stages were diagnosed based on swept-source optical coherence tomography (SS-OCT). Linear mixed effect model was used to determine whether age, gender, diabetes mellitus (DM), hypertension (HT), dyslipidemia (DL), and smoking status were associated with various stages of PVD. As a result, the multivariable analysis disclosed that the associations between older age and higher PVD stages (estimate [95% CI], 0.031 [0.020 to 0.042]; P < 0.0001), and current smokers and lower PVD stages (estimate [95% CI], - 0.24 [- 0.43 to - 0.056]; P = 0.011) were statistically significant. In contrast, female gender was not an independent factor affecting PVD stages in the elderly. Our analysis indicated that higher PVD stages observed in female eyes may be due to confounding effect, in which current smokers were predominantly males (i.e., 12.6% among males vs. 3.9% among females, P < 0.0001). In conclusion, our findings suggest that continuous smoking is associated with an adherent vitreoretinal interface in the elderly.
- Published
- 2020
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16. Visualization of the distribution of nanoparticle-formulated AZD2811 in mouse tumor model using matrix-assisted laser desorption ionization mass spectrometry imaging.
- Author
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Ryu S, Ohuchi M, Yagishita S, Shimoi T, Yonemori K, Tamura K, Fujiwara Y, and Hamada A
- Subjects
- Acetanilides pharmacokinetics, Animals, Antineoplastic Agents pharmacokinetics, Cell Line, Tumor, Drug Carriers analysis, Drug Carriers pharmacokinetics, Male, Mammary Neoplasms, Experimental chemistry, Mice, Mice, Inbred BALB C, Neoplasm Transplantation, Neoplasms, Experimental chemistry, Quinazolines pharmacokinetics, Acetanilides analysis, Antineoplastic Agents analysis, Nanoparticles analysis, Neoplasms chemistry, Quinazolines analysis, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods
- Abstract
Penetration of nanoparticles into viable tumor regions is essential for an effective response. Mass spectrometry imaging (MSI) is a novel method for evaluating the intratumoral pharmacokinetics (PK) of a drug in terms of spatial distribution. The application of MSI for analysis of nanomedicine PK remains in its infancy. In this study, we evaluated the applicability of MALDI-MSI for nanoparticle-formulated drug visualization in tumors and biopsies, with an aim toward future application in clinical nanomedicine research. We established an analytic method for the free drug (AZD2811) and then applied it to visualize nanoparticle-formulated AZD2811. MSI analysis demonstrated heterogeneous intratumoral drug distribution in three xenograft tumors. The intensity of MSI signals correlated well with total drug concentration in tumors, indicating that drug distribution can be monitored quantitatively. Analysis of tumor biopsies indicated that MSI is applicable for analyzing the distribution of nanoparticle-formulated drugs in tumor biopsies, suggesting clinical applicability.
- Published
- 2020
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17. Defective development and microcirculation of intestine in Npr2 mutant mice.
- Author
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Sogawa-Fujiwara C, Hanagata A, Fujiwara Y, Ishida Y, Tomiyasu H, Kunieda T, Nakatomi H, and Hori M
- Subjects
- Animals, Cyclic GMP metabolism, Female, Gastrointestinal Tract blood supply, Intestinal Diseases etiology, Intestinal Diseases metabolism, Intestines blood supply, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Signal Transduction, Gastrointestinal Tract pathology, Intestinal Diseases pathology, Intestines pathology, Microcirculation, Receptors, Atrial Natriuretic Factor physiology
- Abstract
Intractable gastrointestinal (GI) diseases often develop during infancy. Our group previously reported that natriuretic peptide receptor B (NPR-B)-deficient Npr2
slw/slw mice exhibit severe intestinal dysfunction, such as stenosis and distention, which resembles the dysfunction observed in Hirschsprung's disease-allied disorders. However, the root cause of intestinal dysfunction and the detailed of pathophysiological condition in the intestine are not yet clear. Here, we report that the intestine of preweaning Npr2slw/slw mice showed bloodless blood vessels, and nodes were found in the lymphatic vessel. Additionally, the lacteals, smooth muscle, blood vessel, and nerves were barely observed in the villi of preweaning Npr2slw/slw mice. Moreover, intramuscular interstitial cells of Cajal (ICC-IM) were clearly reduced. In contrast, villi and ICC-IM were developed normally in surviving adult Npr2slw/slw mice. However, adult Npr2slw/slw mice exhibited partially hypoplastic blood vessels and an atrophied enteric nervous. Furthermore, adult Npr2slw/slw mice showed markedly reduced white adipose tissue. These findings suggest that the cause of GI dysfunction in preweaning Npr2slw/slw mice is attributed to defective intestinal development with microcirculation disorder. Thus, it is suggested that NPR-B signaling is involved in intestinal development and control of microcirculation and fat metabolism. This report provides new insights into intractable GI diseases, obesity, and NPR-B signaling.- Published
- 2020
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18. Publisher Correction: Relationship between Macroeconomic Indicators and Economic Cycles in U.S.
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Iyetomi H, Aoyama H, Fujiwara Y, Souma W, Vodenska I, and Yoshikawa H
- Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Published
- 2020
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19. Relationship between Macroeconomic Indicators and Economic Cycles in U.S.
- Author
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Iyetomi H, Aoyama H, Fujiwara Y, Souma W, Vodenska I, and Yoshikawa H
- Abstract
We analyze monthly time series of 57 US macroeconomic indicators (18 leading, 30 coincidental, and 9 lagging) and 5 other trade/money indexes. Using novel methods, we confirm statistically significant co-movements among these time series and identify noteworthy economic events. The methods we use are Complex Hilbert Principal Component Analysis (CHPCA) and Rotational Random Shuffling (RRS). We obtain significant complex correlations among the US economic indicators with leads/lags. We then use the Hodge decomposition to obtain the hierarchical order of each time series. The Hodge potential allows us to better understand the lead/lag relationships. Using both CHPCA and Hodge decomposition approaches, we obtain a new lead/lag order of the macroeconomic indicators and perform clustering analysis for positively serially correlated positive and negative changes of the analyzed indicators. We identify collective negative co-movements around the Dot.com bubble in 2001 as well as the Global Financial Crisis (GFC) in October 2008. We also identify important events such as the Hurricane Katrina in August 2005 and the Oil Price Crisis in July 2008. Additionally, we demonstrate that some coincidental and lagging indicators actually show leading indicator characteristics. This suggests that there is a room for existing indicators to be improved.
- Published
- 2020
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20. Slco2a1 deficiency exacerbates experimental colitis via inflammasome activation in macrophages: a possible mechanism of chronic enteropathy associated with SLCO2A1 gene.
- Author
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Nakata R, Nakamura Y, Hosomi S, Okuda H, Nishida Y, Sugita N, Itani S, Nadatani Y, Otani K, Tanaka F, Kamata N, Taira K, Nagami Y, Tanigawa T, Watanabe T, Yamagami H, Nakanishi T, and Fujiwara Y
- Subjects
- Animals, Blotting, Western, Cells, Cultured, Colitis genetics, Dextran Sulfate toxicity, Enterocolitis chemically induced, Enterocolitis genetics, Enterocolitis metabolism, Enterocolitis pathology, Enzyme-Linked Immunosorbent Assay, Inflammasomes immunology, Inflammasomes metabolism, Macrophages drug effects, Macrophages metabolism, Mice, Models, Theoretical, NLR Family, Pyrin Domain-Containing 3 Protein genetics, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Organic Anion Transporters genetics, Reverse Transcriptase Polymerase Chain Reaction, Colitis chemically induced, Colitis metabolism, Colitis pathology, Organic Anion Transporters deficiency, Organic Anion Transporters metabolism
- Abstract
Loss-of-function mutations in the solute carrier organic anion transporter family, member 2a1 gene (SLCO2A1), which encodes a prostaglandin (PG) transporter, have been identified as causes of chronic nonspecific multiple ulcers in the small intestine; however, the underlying mechanisms have not been revealed. We, therefore, evaluated the effects of systemic knockout of Slco2a1 (Slco2a1
-/- ) and conditional knockout in intestinal epithelial cells (Slco2a1ΔIEC ) and macrophages (Slco2a1ΔMP ) in mice with dextran sodium sulphate (DSS)-induced acute colitis. Slco2a-/- mice were more susceptible to DSS-induced colitis than wild-type (WT) mice, but did not spontaneously develop enteritis or colitis. The nucleotide-binding domain, leucine-rich repeats containing family, pyrin domain-containing-3 (NLRP3) inflammasome was more strongly upregulated in colon tissues of Slco2a-/- mice administered DSS and in macrophages isolated from Slco2a1-/- mice than in the WT counterparts. Slco2a1ΔMP , but not Slco2a1ΔIEC mice, were more susceptible to DSS-induced colitis than WT mice, partly phenocopying Slco2a-/- mice. Concentrations of PGE2 in colon tissues and macrophages from Slco2a1-/- mice were significantly higher than those of WT mice. Blockade of inflammasome activation suppressed the exacerbation of colitis. These results indicated that Slco2a1-deficiency increases the PGE2 concentration, resulting in NLRP3 inflammasome activation in macrophages, thus exacerbating intestinal inflammation.- Published
- 2020
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21. Gastric acid inhibitor aggravates indomethacin-induced small intestinal injury via reducing Lactobacillus johnsonii.
- Author
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Nadatani Y, Watanabe T, Suda W, Nakata A, Matsumoto Y, Kosaka S, Higashimori A, Otani K, Hosomi S, Tanaka F, Nagami Y, Kamata N, Taira K, Yamagami H, Tanigawa T, Hattori M, and Fujiwara Y
- Subjects
- Animals, Disease Models, Animal, Dysbiosis microbiology, Fecal Microbiota Transplantation, High-Throughput Nucleotide Sequencing, Humans, Indomethacin administration & dosage, Injections, Intraperitoneal, Intestine, Small drug effects, Intestine, Small microbiology, Lactobacillus johnsonii drug effects, Lactobacillus johnsonii physiology, Male, Mice, Mice, Inbred C57BL, Proton Pump Inhibitors administration & dosage, Pyrroles administration & dosage, Pyrroles adverse effects, RNA, Ribosomal, 16S genetics, Rabeprazole administration & dosage, Rabeprazole adverse effects, Sequence Analysis, DNA, Sulfonamides administration & dosage, Sulfonamides adverse effects, Dysbiosis chemically induced, Indomethacin adverse effects, Intestine, Small injuries, Lactobacillus johnsonii isolation & purification, Proton Pump Inhibitors adverse effects
- Abstract
Proton pump inhibitors (PPIs) alter the composition of the intestinal microbiome, exacerbating indomethacin (IND)-induced small intestinal damage. Vonoprazan fumarate inhibits gastric acid secretion using a different mechanism from PPIs. We investigated the effects of both drugs on the intestinal microbiome and IND-induced small intestinal damage. We sought to clarify whether PPI-induced dysbiosis and worsening of the damage were due to a specific drug class effect of PPIs. Rabeprazole administration increased operational taxonomic unit numbers in the small intestines of C57BL/6 J mice, whereas the difference was not significant in the vonoprazan-treated group but exhibited a trend. Permutational multivariate analysis of variance of the unweighted UniFrac distances showed significant differences between vehicle- and vonoprazan- or rabeprazole-treated groups. L. johnsonii was the predominant microbial species, and the population ratio decreased after vonoprazan and rabeprazole administration. The vonoprazan- and rabeprazole-treated groups showed increased IND-induced damage. This high sensitivity to IND-induced damage was evaluated by transplantation with contents from the small intestine of mice treated with either vonoprazan or rabeprazole. Supplementation of L. johnsonii orally in mice treated with rabeprazole and vonoprazan prevented the increase in IND-induced small intestinal damage. In conclusion, both rabeprazole and vonoprazan aggravated NSAID-induced small intestinal injury by reducing the population of L. johnsonii in the small intestine via suppressing gastric acid secretion.
- Published
- 2019
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22. High-fat diet-mediated dysbiosis exacerbates NSAID-induced small intestinal damage through the induction of interleukin-17A.
- Author
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Sugimura N, Otani K, Watanabe T, Nakatsu G, Shimada S, Fujimoto K, Nadatani Y, Hosomi S, Tanaka F, Kamata N, Taira K, Nagami Y, Tanigawa T, Uematsu S, and Fujiwara Y
- Subjects
- Animals, Bifidobacterium classification, Bifidobacterium drug effects, Bifidobacterium isolation & purification, Dextrans metabolism, Disease Models, Animal, Dysbiosis blood, Dysbiosis chemically induced, Fluorescein-5-isothiocyanate analogs & derivatives, Fluorescein-5-isothiocyanate metabolism, Indomethacin adverse effects, Intestine, Small drug effects, Intestine, Small immunology, Lipopolysaccharides blood, Male, Mice, Mice, Inbred C57BL, Permeability drug effects, Sequence Analysis, DNA, Up-Regulation, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Diet, High-Fat adverse effects, Dysbiosis microbiology, Interleukin-17 genetics, Intestine, Small microbiology, RNA, Ribosomal, 16S genetics
- Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) cause damage in the small intestine in a bacteria-dependent manner. As high-fat diet (HFD) is a potent inducer of gut dysbiosis, we investigated the effects of HFD on bacterial flora in the small intestine and NSAID-induced enteropathy. 16S rRNA gene analysis revealed that the population of Bifidobacterium spp. significantly decreased by fold change of individual operational taxonomic units in the small intestine of mice fed HFD for 8 weeks. HFD increased intestinal permeability, as indicated by fluorescein isothiocyanate-dextran absorption and serum lipopolysaccharide levels, accompanied by a decrease in the protein expressions of ZO-1 and occludin and elevated mRNA expression of interleukin (IL)-17A in the small intestine. HFD-fed mice exhibited increased susceptibility to indomethacin-induced damage in the small intestine; this phenotype was observed in normal diet-fed mice that received small intestinal microbiota from HFD-fed mice. Administration of neutralizing antibodies against IL-17A to HFD-fed mice reduced intestinal permeability and prevented exacerbation of indomethacin-induced damage. Thus, HFD-induced microbial dysbiosis in small intestine caused microinflammation through the induction of IL-17A and increase in intestinal permeability, resulting in the aggravation of NSAID-induced small intestinal damage.
- Published
- 2019
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23. Increased regulatory B cells are involved in immune evasion in patients with gastric cancer.
- Author
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Murakami Y, Saito H, Shimizu S, Kono Y, Shishido Y, Miyatani K, Matsunaga T, Fukumoto Y, Ashida K, Sakabe T, Nakayama Y, and Fujiwara Y
- Subjects
- Aged, Case-Control Studies, Cell Count, Female, Humans, Male, Prognosis, Stomach Neoplasms diagnosis, B-Lymphocytes, Regulatory cytology, Immune Evasion immunology, Stomach Neoplasms immunology
- Abstract
Accumulating evidence has indicated that immune regulatory cells are involved in the establishment of tumoral immune evasion. However, the role of regulatory B cells (Bregs) in this remains unclear. Here, we identified a role for Bregs in immune evasion in gastric cancer (GC) patients. The frequency of peripheral Bregs was significantly higher in GC patients than in healthy controls (P = 0.0023). Moreover, the frequency of CD19
+ CD24hi CD27+ B cells in GC tissue was significantly higher than in peripheral blood and healthy gastric tissue. Carboxyfluorescein succinimidyl ester labeling revealed that CD19+ CD24hi CD27+ B cells could suppress the proliferation of autologous CD4+ T cells. Moreover, CD19+ CD24hi CD27+ B cells inhibited the production of interferon-gamma by CD4+ T cells. Double staining immunohistochemistry of interleukin-10 and CD19 revealed 5-year overall survival rates of 65.4% and 13.3% in BregLow and BregHigh groups, respectively (P < 0.0001). Multivariate analysis indicated that the frequency of Bregs was an independent prognostic indicator in GC patients. Taken together, our results show the existence of Bregs in GC tissue, and indicate that they are significantly correlated with the prognosis of GC patients.- Published
- 2019
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- View/download PDF
24. Methylmercury induces the expression of chemokine CCL4 via SRF activation in C17.2 mouse neural stem cells.
- Author
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Kim MS, Takahashi T, Lee JY, Toyama T, Hoshi T, Kuge S, Fujiwara Y, Naganuma A, and Hwang GW
- Subjects
- Animals, Brain metabolism, Cell Line, Cells, Cultured, Chemokine CCL4 physiology, Gene Expression Regulation drug effects, MAP Kinase Signaling System, Methylmercury Compounds metabolism, Methylmercury Compounds toxicity, Mice, NF-kappa B metabolism, Neural Stem Cells metabolism, Promoter Regions, Genetic genetics, Serum Response Factor physiology, Signal Transduction, Transcription Factors metabolism, Chemokine CCL4 metabolism, Methylmercury Compounds adverse effects, Serum Response Factor metabolism
- Abstract
Methylmercury is an environmental pollutant that causes specific and serious damage to the central nervous system. We have previously shown that C-C motif chemokine ligand 4 (CCL4) protects cultured neural cells from methylmercury toxicity and expression of CCL4 is specifically induced in mouse brain by methylmercury. In this study, we examined the transcriptional regulatory mechanism that induces CCL4 expression by methylmercury using C17.2 mouse neural stem cells. The promoter region of the CCL4 gene was analyzed by a reporter assay, revealing that the region up to 50 bp upstream from the transcription start site was necessary for inducing expression of CCL4 by methylmercury. Nine transcription factors that might bind to this upstream region and be involved in the induction of CCL4 expression by methylmercury were selected, and the induction of CCL4 expression by methylmercury was suppressed by the knockdown of serum response factor (SRF). In addition, the nuclear level of SRF was elevated by methylmercury, and an increase in the amount bound to the CCL4 gene promoter was also observed. Furthermore, we examined the upstream signaling pathway involved in the induction of CCL4 expression by SRF, and confirmed that activation of p38 and ERK, which are part of the MAPK pathway, are involved. These results suggest that methylmercury induces the expression of CCL4 by activating SRF via the p38 and ERK signaling pathway. Our findings are important for elucidating the mechanism involved in the brain-specific induction of CCL4 expression by methylmercury.
- Published
- 2019
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- View/download PDF
25. Enhanced light extraction efficiency of Eu-related emission from a nano-patterned GaN layer grown by MOCVD.
- Author
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Lesage A, Timmerman D, Inaba T, Gregorkiewicz T, and Fujiwara Y
- Abstract
Eu-doped GaN is a promising material for the active layer in red light emitting diodes. Although the output power of LEDs based on GaN:Eu has been increasing by a combination of structural and growth optimizations, there is still a significant limitation resulting from a poor light extraction efficiency, typical for high refractive index materials. Here we studied nanostructuring of the top of the optical active layer by nano-cubes for enhancement of the light extraction efficiency, and its effect on the optical emission characteristics. By etching nano-cubes into the active layer, we observed an increase in directional light output power of Eu
3+ ions of up to 60%, as well as a grating effect. Simultaneously, the absorption of excitation light into the optical active layer was improved, leading to a 12.8 times increase of output power per available Eu3+ ion.- Published
- 2019
- Full Text
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26. Effect of intravitreal or sub-tenon triamcinolone acetonide injection at completion of vitrectomy on peripheral retinochoroidal thickness in eyes with proliferative diabetic retinopathy.
- Author
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Fujiwara Y, Iwase T, Yamamoto K, Ueno Y, Ra E, and Terasaki H
- Subjects
- Administration, Ophthalmic, Adult, Aged, Eye pathology, Female, Humans, Intravitreal Injections methods, Male, Middle Aged, Retrospective Studies, Vitrectomy methods, Diabetic Retinopathy therapy, Eye drug effects, Triamcinolone Acetonide pharmacology
- Abstract
The effect of triamcinolone acetonide (TA) on the peripheral retinochoroidal thickness was determined after pars plana vitrectomy (PPV) with scatter photocoagulation in eyes with proliferative diabetic retinopathy. The peripheral retinochoroidal thickness was measured at 5 mm from the limbus in the four quadrants using anterior segment optical coherence tomography before, and 3 days, and 1 and 2 weeks after the surgery. The total peripheral thickness was significantly thicker than the baseline thickness after PPV alone (P < 0.001; 18 eyes), PPV combined with intravitreal TA injection (IVTA; P = 0.011; 19 eyes), and PPV combined with sub-tenon TA injection (STTA; P = 0001; 23 eyes). The total peripheral thickness in the PPV group at 3 days after surgery was significantly thicker than that of the PPV + IVTA (P = 0.015) and of the PPV + STTA groups (P = 0.016). Multiple linear regression analyses showed that the injection of TA by the two routes and the number of photocoagulation burns were significantly correlated with the total peripheral thicknesses at 3 days after the surgery. The results indicate that the PPV with large number of intraoperative scatter photocoagulation burns caused an increase in the total peripheral thickness and an administration of either IVTA and STTA can reduced the degree of thickening.
- Published
- 2019
- Full Text
- View/download PDF
27. Effective nose-to-brain delivery of exendin-4 via coadministration with cell-penetrating peptides for improving progressive cognitive dysfunction.
- Author
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Kamei N, Okada N, Ikeda T, Choi H, Fujiwara Y, Okumura H, and Takeda-Morishita M
- Subjects
- Administration, Intranasal, Amyloid beta-Peptides metabolism, Animals, Brain pathology, Cognitive Dysfunction metabolism, Cognitive Dysfunction pathology, Exenatide pharmacokinetics, Exenatide pharmacology, Exenatide therapeutic use, Glucagon-Like Peptide 1 administration & dosage, Glucagon-Like Peptide 1 pharmacokinetics, Glucagon-Like Peptide 1 pharmacology, Glucagon-Like Peptide 1 therapeutic use, Hypoglycemic Agents pharmacokinetics, Hypoglycemic Agents pharmacology, Hypoglycemic Agents therapeutic use, Insulin metabolism, Male, Memory Disorders drug therapy, Memory Disorders metabolism, Memory Disorders pathology, Mice, Signal Transduction drug effects, Brain drug effects, Brain metabolism, Cell-Penetrating Peptides metabolism, Cognitive Dysfunction drug therapy, Drug Carriers metabolism, Exenatide administration & dosage, Hypoglycemic Agents administration & dosage
- Abstract
In a recent study, we demonstrated the potential of a cell-penetrating peptide (CPP) penetratin to deliver the peptide drug insulin to the brain via nasal administration, and its pharmacological effect on the mild cognitive dysfunction in senescence-accelerated mouse (SAMP8). However, the therapeutic potential of intranasal insulin administration was attenuated when applied to the aged SAMP8 with severe cognitive dysfunction. The present study, therefore, aimed to overcome the difficulty in treating severe cognitive dysfunction using insulin by investigating potential alternatives, glucagon-like peptide-1 (GLP-1) receptor agonists such as exendin-4. Examination using normal ddY mice demonstrated that the distribution of exendin-4 throughout the brain was dramatically increased by intranasal coadministration with the L-form of penetratin. The activation of hippocampal insulin signaling after the simultaneous nose-to-brain delivery of exendin-4 and an adequate level of insulin were confirmed by analyzing the phosphorylation of Akt. Furthermore, spatial learning ability, evaluated in the Morris water maze test after daily administration of exendin-4 with L-penetratin and supplemental insulin for 4 weeks, suggested therapeutic efficacy against severe cognitive dysfunction. The present study suggests that nose-to-brain delivery of exendin-4 with supplemental insulin, mediated by CPP coadministration, shows promise for the treatment of progressive cognitive dysfunction in SAMP8.
- Published
- 2018
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28. Longitudinal effects of aging on 18 F-FDG distribution in cognitively normal elderly individuals.
- Author
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Ishibashi K, Onishi A, Fujiwara Y, Oda K, Ishiwata K, and Ishii K
- Subjects
- Age Factors, Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Fluorodeoxyglucose F18 administration & dosage, Healthy Volunteers, Humans, Longitudinal Studies, Male, Middle Aged, Positron-Emission Tomography, Radiopharmaceuticals administration & dosage, Aging, Cerebral Cortex diagnostic imaging, Fluorodeoxyglucose F18 pharmacokinetics, Radiopharmaceuticals pharmacokinetics
- Abstract
Previous studies of aging effects on fluorine-18-labeled fluorodeoxyglucose (
18 F-FDG) distribution have employed cross-sectional designs. We examined aging effects on18 F-FDG distribution using both cross-sectional and longitudinal assessments. We obtained two18 F-FDG positron emission tomography scans at two different time points from 107 cognitively normal elderly participants. The participants' mean ages at baseline and second scans were 67.9 and 75.7, respectively. The follow-up period ranged from 4 to 11 years with a mean of 7.8 years. The voxel-wise analysis revealed significant clusters in which18 F-FDG uptake was decreased between baseline and second scans (p < 0.05, family-wise error corrected) in the anterior cingulate cortex (ACC), posterior cingulate cortex/precuneus (PCC/PC), and lateral parietal cortex (LPC). The cross-sectional analysis of18 F-FDG uptake and age showed significant correlations in the ACC (p = 0.016) but not the PCC/PC (p = 0.240) at baseline, and in the ACC (p = 0.004) and PCC/PC (p = 0.002) at the second scan. The results of longitudinal assessments suggested that18 F-FDG uptake in the ACC, PCC/PC, and LPC decreased with advancing age in cognitively normal elderly individuals, and those of the cross-sectional assessments suggested that the trajectories of age-associated18 F-FDG decreases differed between the ACC and PCC/PC.- Published
- 2018
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29. Faunal activity rhythms influencing early community succession of an implanted whale carcass offshore Sagami Bay, Japan.
- Author
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Aguzzi J, Fanelli E, Ciuffardi T, Schirone A, De Leo FC, Doya C, Kawato M, Miyazaki M, Furushima Y, Costa C, and Fujiwara Y
- Subjects
- Acoustics instrumentation, Analysis of Variance, Animals, Bays, Body Weight, Brachyura physiology, Eels physiology, Japan, Male, Multivariate Analysis, Predatory Behavior, Sharks physiology, Video Recording, Body Remains, Ecological Parameter Monitoring methods, Food Chain, Periodicity, Sperm Whale, Tidal Waves
- Abstract
Benthic community succession patterns at whale falls have been previously established by means of punctual submersible and ROV observations. The contribution of faunal activity rhythms in response to internal tides and photoperiod cues to that community succession dynamism has never been evaluated. Here, we present results from a high-frequency monitoring experiment of an implanted sperm whale carcass in the continental slope (500 m depth) offshore Sagami Bay, Japan. The benthic community succession was monitored at a high frequency in a prolonged fashion (i.e. 2-h intervals for 2.5 months) with a seafloor lander equipped with a time-lapse video camera and an acoustic Doppler profiler to concomitantly study current flow dynamics. We reported here for the first time, to the best of our knowledge, the occurrence of strong 24-h day-night driven behavioral rhythms of the most abundant species (Simenchelys parasitica; Macrocheira kaempferi, and Pterothrissus gissu). Those rhythms were detected in detriment of tidally-controlled ones. Evidence of a diel temporal niche portioning between scavengers and predators avoiding co-occurrence at the carcass, is also provided. The high-frequency photographic and oceanographic data acquisition also helped to precisely discriminate the transition timing between the successional stages previously described for whale falls' attendant communities.
- Published
- 2018
- Full Text
- View/download PDF
30. Physics of Efficiency Droop in GaN:Eu Light-Emitting Diodes.
- Author
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Fragkos IE, Dierolf V, Fujiwara Y, and Tansu N
- Abstract
The internal quantum efficiency (IQE) of an electrically-driven GaN:Eu based device for red light emission is analyzed in the framework of a current injection efficiency model (CIE). The excitation path of the Eu
+3 ion is decomposed in a multiple level system, which includes the carrier transport phenomena across the GaN/GaN:Eu/GaN active region of the device, and the interactions among traps, Eu+3 ions and the GaN host. The identification and analysis of the limiting factors of the IQE are accomplished through the CIE model. The CIE model provides a guidance for high IQE in the electrically-driven GaN:Eu based red light emitters.- Published
- 2017
- Full Text
- View/download PDF
31. Pathway Towards High-Efficiency Eu-doped GaN Light-Emitting Diodes.
- Author
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Fragkos IE, Tan CK, Dierolf V, Fujiwara Y, and Tansu N
- Abstract
A physically intuitive current injection efficiency model for a GaN:Eu quantum well (QW) has been developed to clarify the necessary means to achieve device quantum efficiency higher than the state-of-the-art GaN:Eu system for red light emission. The identification and analysis of limiting factors for high internal quantum efficiencies (IQE) are accomplished through the current injection efficiency model. In addition, the issue of the significantly lower IQE in the electrically-driven GaN:Eu devices in comparison to the optically-pumped GaN:Eu devices is clarified in the framework of this injection efficiency model. The improved understanding of the quantum efficiency issue through current injection efficiency model provides a pathway to address the limiting factors in electrically-driven devices. Based on our developed injection efficiency model, several experimental approaches have been suggested to address the limitations in achieving high IQE GaN:Eu QW based devices in red spectral regime.
- Published
- 2017
- Full Text
- View/download PDF
32. Diverse coordinate frames on sensorimotor areas in visuomotor transformation.
- Author
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Fujiwara Y, Lee J, Ishikawa T, Kakei S, and Izawa J
- Subjects
- Adult, Brain Mapping, Female, Humans, Magnetic Resonance Imaging, Male, Motor Cortex physiology, Movement, Neural Pathways physiology, Parietal Lobe physiology, Posture, Proprioception, Young Adult, Psychomotor Performance, Sensorimotor Cortex physiology
- Abstract
The visuomotor transformation during a goal-directed movement may involve a coordinate transformation from visual 'extrinsic' to muscle-like 'intrinsic' coordinate frames, which might be processed via a multilayer network architecture composed of neural basis functions. This theory suggests that the postural change during a goal-directed movement task alters activity patterns of the neurons in the intermediate layer of the visuomotor transformation that recieves both visual and proprioceptive inputs, and thus influence the multi-voxel pattern of the blood oxygenation level dependent signal. Using a recently developed multi-voxel pattern decoding method, we found extrinsic, intrinsic and intermediate coordinate frames along the visuomotor cortical pathways during a visuomotor control task. The presented results support the hypothesis that, in human, the extrinsic coordinate frame was transformed to the muscle-like frame over the dorsal pathway from the posterior parietal cortex and the dorsal premotor cortex to the primary motor cortex.
- Published
- 2017
- Full Text
- View/download PDF
33. Evaluation of the heterogeneous tissue distribution of erlotinib in lung cancer using matrix-assisted laser desorption ionization mass spectrometry imaging.
- Author
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Tsubata Y, Hayashi M, Tanino R, Aikawa H, Ohuchi M, Tamura K, Fujiwara Y, Isobe T, and Hamada A
- Subjects
- Animals, Humans, Lung diagnostic imaging, Lung drug effects, Lung Neoplasms diagnostic imaging, Lung Neoplasms pathology, Mice, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Tissue Distribution drug effects, Xenograft Model Antitumor Assays, Erlotinib Hydrochloride administration & dosage, Lung Neoplasms drug therapy, Protein Kinase Inhibitors administration & dosage
- Abstract
Although drug distribution in tumor tissues has a significant impact on efficacy, conventional pharmacokinetic analysis has some limitations with regard to its ability to provide a comprehensive assessment of drug tissue distribution. Erlotinib is a tyrosine kinase inhibitor that acts on the epidermal growth factor receptor; however, it is unclear how this drug is histologically distributed in lung cancer. We used matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to analyze erlotinib distribution in the tumor and normal lung tissues of a mouse xenograft model and patient with non-small cell lung cancer. LC-MS/MS showed that the erlotinib tissue concentration in the xenograft tumor tissue was clearly lower than that in the normal tissue at the time of maximum blood concentration. MALDI-MSI showed the heterogeneous distribution of erlotinib at various levels in the murine tissues; interestingly, erlotinib was predominantly localized in the area of viable tumor compared to the necrotic area. In the patient-derived tissue, MALDI-MSI showed that there were different concentrations of erlotinib distributed within the same tissue. For drug development and translational research, the imaging pharmacokinetic study used the combination of MALDI-MSI and LC-MS/MS analyses may be useful in tissues with heterogeneous drug distribution.
- Published
- 2017
- Full Text
- View/download PDF
34. Structural insights into the nucleotide base specificity of P2X receptors.
- Author
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Kasuya G, Fujiwara Y, Tsukamoto H, Morinaga S, Ryu S, Touhara K, Ishitani R, Furutani Y, Hattori M, and Nureki O
- Subjects
- Animals, Binding Sites, Cytidine Triphosphate chemistry, Molecular Docking Simulation, Protein Binding, Receptors, Purinergic P2X metabolism, Xenopus laevis, Zebrafish, Zebrafish Proteins metabolism, Cytidine Triphosphate metabolism, Receptors, Purinergic P2X chemistry, Zebrafish Proteins chemistry
- Abstract
P2X receptors are trimeric ATP-gated cation channels involved in diverse physiological processes, ranging from muscle contraction to nociception. Despite the recent structure determination of the ATP-bound P2X receptors, the molecular mechanism of the nucleotide base specificity has remained elusive. Here, we present the crystal structure of zebrafish P2X4 in complex with a weak affinity agonist, CTP, together with structure-based electrophysiological and spectroscopic analyses. The CTP-bound structure revealed a hydrogen bond, between the cytosine base and the side chain of the basic residue in the agonist binding site, which mediates the weak but significant affinity for CTP. The cytosine base is further recognized by two main chain atoms, as in the ATP-bound structure, but their bond lengths seem to be extended in the CTP-bound structure, also possibly contributing to the weaker affinity for CTP over ATP. This work provides the structural insights for the nucleotide base specificity of P2X receptors.
- Published
- 2017
- Full Text
- View/download PDF
35. NLRP3 inflammasome has a protective effect against oxazolone-induced colitis: a possible role in ulcerative colitis.
- Author
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Itani S, Watanabe T, Nadatani Y, Sugimura N, Shimada S, Takeda S, Otani K, Hosomi S, Nagami Y, Tanaka F, Kamata N, Yamagami H, Tanigawa T, Shiba M, Tominaga K, Fujiwara Y, and Arakawa T
- Subjects
- Adult, Aged, Aged, 80 and over, Animals, Caspase 1 metabolism, Colitis chemically induced, Colitis genetics, Colitis, Ulcerative genetics, Cytokines metabolism, Disease Models, Animal, Female, Gene Expression Regulation, Gene Knockout Techniques, Humans, Macrophages immunology, Male, Mice, Middle Aged, Severity of Illness Index, Young Adult, Colitis immunology, Colitis, Ulcerative immunology, Inflammasomes metabolism, NLR Family, Pyrin Domain-Containing 3 Protein genetics, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Oxazolone adverse effects
- Abstract
The inflammasomes induce maturation of pro-interleukin-1β (IL-1β) and pro-IL-18. We investigated roles of the NLRP3 inflammasome in the pathogenesis of ulcerative colitis (UC). After induction of oxazolone-induced colitis, a mouse UC model, colonic tissues were assayed for inflammatory mediators. Histological studies were performed on inflamed colonic tissue from mice and UC patients. Histological severity of murine colitis peaked on day 1, accompanied by an increase in the expression of Th2 cytokines including IL-4 and IL-13. Oxazolone treatment stimulated maturation of pro-caspase-1 and pro-IL-1β, while it reduced IL-18 expression. Either exogenous IL-1β or IL-18 ameliorated the colitis with or without reduction in Th2 cytokine expression, respectively. Induction of colitis decreased MUC2 expression, which was reversed by administration of IL-18, but not IL-1β. Compared to wild-type mice, NLRP3
-/- mice exhibited higher sensitivity to oxazolone treatment with enhancement of Th2 cytokine expression and reduction of mature IL-1β and IL-18 production; this phenotype was rescued by exogenous IL-1β or IL-18. Immunofluorescent studies revealed positive correlation of NLRP3 expression with disease severity in UC patients, and localization of the inflammasome-associated molecules in macrophages. The NLRP3 inflammasome-derived IL-1β and IL-18 may play a protective role against UC through different mechanisms., Competing Interests: Toshio Watanabe, Tetsuya Tanigawa, Kazunari Tominaga and Yasuhiro Fujiwara – Faculty member of a course sponsored by Eisai Co., Ltd. The other authors have declared that no competing interests exist.- Published
- 2016
- Full Text
- View/download PDF
36. Small-sized, stable lipid nanoparticle for the efficient delivery of siRNA to human immune cell lines.
- Author
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Nakamura T, Kuroi M, Fujiwara Y, Warashina S, Sato Y, and Harashima H
- Subjects
- Cell Line, Gene Silencing, Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) genetics, Humans, Jurkat Cells, Killer Cells, Natural, Nanoparticles toxicity, Particle Size, Lipids chemistry, Nanoparticles chemistry, RNA, Small Interfering administration & dosage, Transduction, Genetic methods
- Abstract
Gene silencing by small interfering RNA (siRNA) is useful for analyzing the functions of human immune cells. However, the transfection of siRNA to human immune cells is difficult. Here, we used a multifunctional envelope-type nanodevice (MEND) containing YSK12-C4 (YSK12-MEND) to efficiently introduce siRNA to human immune cell lines, Jurkat, THP-1, KG-1 and NK92. The YSK12-MEND was transfected to human immune cell lines at a siRNA dose range of 1-30 nM, resulting that maximum gene silencing efficiencies at the mRNA level in Jurkat, THP-1, KG-1 and NK92 were 96%, 96%, 91% and 75%, respectively. The corresponding values for Lipofectamine RNAiMAX (RNAiMAX) were 37%, 56%, 43% and 19%, respectively. The process associated with cellular uptake played a role in effective gene silencing effect of the YSK12-MEND. The small size and high non-aggregability of the YSK12-MEND were advantageous for the cellular internalization of siRNA to immune cell lines. In the case of RNAiMAX, a drastic increase in particles size was observed in the medium used, which inhibited cellular uptake. The YSK12-MEND reported in herein appears to be appropriate for delivering siRNA to human immune cells, and the small particle size and non-aggregability are essential properties.
- Published
- 2016
- Full Text
- View/download PDF
37. Colchicine prevents NSAID-induced small intestinal injury by inhibiting activation of the NLRP3 inflammasome.
- Author
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Otani K, Watanabe T, Shimada S, Takeda S, Itani S, Higashimori A, Nadatani Y, Nagami Y, Tanaka F, Kamata N, Yamagami H, Tanigawa T, Shiba M, Tominaga K, Fujiwara Y, and Arakawa T
- Subjects
- Animals, Caspase 1 metabolism, Indomethacin administration & dosage, Indomethacin adverse effects, Interleukin-1beta pharmacology, Intestine, Small drug effects, Intestine, Small enzymology, Intestine, Small pathology, Mice, Inbred C57BL, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Colchicine pharmacology, Inflammasomes metabolism, Intestine, Small injuries, NLR Family, Pyrin Domain-Containing 3 Protein metabolism
- Abstract
The inflammasome is a large, multiprotein complex that consists of a nucleotide-binding oligomerization domain-like receptor (NLR), an apoptosis-associated speck-like protein containing a caspase recruitment domain, and pro-caspase-1. Activation of the inflammasome results in cleavage of pro-caspase-1 into cleaved caspase-1, which promotes the processing of pro-interleukin (IL)-1β into mature IL-1β. We investigated the effects of colchicine on non-steroidal anti-inflammatory drug (NSAID)-induced small intestinal injury and activation of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome. Colchicine treatment inhibited indomethacin-induced small intestinal injury by 86% (1 mg/kg) and 94% (3 mg/kg) as indicated by the lesion index 24 h after indomethacin administration. Colchicine inhibited the protein expression of cleaved caspase-1 and mature IL-1β, without affecting the mRNA expression of NLRP3 and IL-1β. Although treatment with recombinant IL-1β (0.1 μg/kg) did not change the severity of small intestinal damage, the preventive effects of colchicine were abolished by supplementation with the same dose of recombinant IL-1β. Indomethacin-induced small intestinal damage was reduced by 77%, as determined by the lesion index in NLRP3(-/-) mice, and colchicine treatment failed to inhibit small intestinal damage in NLRP3(-/-) mice. These results demonstrate that colchicine prevents NSAID-induced small intestinal injury by inhibiting activation of the NLRP3 inflammasome.
- Published
- 2016
- Full Text
- View/download PDF
38. Onionin A inhibits ovarian cancer progression by suppressing cancer cell proliferation and the protumour function of macrophages.
- Author
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Tsuboki J, Fujiwara Y, Horlad H, Shiraishi D, Nohara T, Tayama S, Motohara T, Saito Y, Ikeda T, Takaishi K, Tashiro H, Yonemoto Y, Katabuchi H, Takeya M, and Komohara Y
- Subjects
- Animals, Antineoplastic Agents pharmacology, Apoptosis drug effects, Cell Line, Tumor, Cytokines metabolism, Disease Progression, Female, Humans, Macrophages metabolism, Mice, Inbred C57BL, STAT3 Transcription Factor metabolism, Survival Rate, Cell Proliferation drug effects, Macrophages drug effects, Ovarian Neoplasms metabolism, Ovarian Neoplasms therapy, Sulfoxides pharmacology, Thiophenes pharmacology
- Abstract
It is well known that tumour-associated macrophages (TAMs) play an important role in tumour development by modulating the tumour microenvironment, and targeting of protumour activation or the M2 polarization of TAMs is expected to be an effective therapy for cancer patients. We previously demonstrated that onionin A (ONA), a natural low molecular weight compound isolated from onions, has an inhibitory effect on M2 macrophage polarization. In the present study, we investigated whether ONA had a therapeutic anti-ovarian cancer effect using in vitro and in vivo studies. We found that ONA reduced the extent of ovarian cancer cell proliferation induced by co-culture with human macrophages. In addition, we also found that ONA directly suppressed cancer cell proliferation. A combinatorial effect with ONA and anti-cancer drugs was also observed. The activation of signal transducer and activator of transcription 3 (STAT3), which is involved in cell proliferation and chemo-resistance, was significantly abrogated by ONA in ovarian cancer cells. Furthermore, the administration of ONA suppressed cancer progression and prolonged the survival time in a murine ovarian cancer model under single and combined treatment conditions. Thus, ONA is considered useful for the additional treatment of patients with ovarian cancer owing to its suppression of the protumour activation of TAMs and direct cytotoxicity against cancer cells.
- Published
- 2016
- Full Text
- View/download PDF
39. Imaging mass spectrometry for the precise design of antibody-drug conjugates.
- Author
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Fujiwara Y, Furuta M, Manabe S, Koga Y, Yasunaga M, and Matsumura Y
- Subjects
- Animals, Antibodies, Monoclonal chemistry, Antineoplastic Agents chemistry, Cell Line, Tumor, Disease Models, Animal, Heterografts, Humans, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Drug Design, Immunoconjugates chemistry, Mass Spectrometry methods
- Abstract
Antibody-drug conjugates (ADCs) are a class of immunotherapeutic agents that enable the delivery of cytotoxic drugs to target malignant cells. Because various cancers and tumour vascular endothelia strongly express anti-human tissue factor (TF), we prepared ADCs consisting of a TF-specific monoclonal antibody (mAb) linked to the anticancer agent (ACA) monomethyl auristatin E (MMAE) via a valine-citrulline (Val-Cit) linker (human TF ADC). Identifying the most efficient drug design in advance is difficult because ADCs have complicated structures. The best method of assessing ADCs is to examine their selectivity and efficiency in releasing and distributing the ACA within tumour tissue. Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) can be used to directly detect the distributions of native molecules within tumour tissues. Here, MALDI-IMS enabled the identification of the intratumour distribution of MMAE released from the ADC. In conclusion, MALDI-IMS is a useful tool to assess ADCs and facilitate the optimization of ADC design.
- Published
- 2016
- Full Text
- View/download PDF
40. Structural basis for the membrane association of ankyrinG via palmitoylation.
- Author
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Fujiwara Y, Kondo HX, Shirota M, Kobayashi M, Takeshita K, Nakagawa A, Okamura Y, and Kinoshita K
- Subjects
- Animals, Axons metabolism, Cell Membrane chemistry, Chromatography, Gel, Crystallography, X-Ray, Cysteine chemistry, Humans, Lipids chemistry, Molecular Dynamics Simulation, Neurons metabolism, Oxidation-Reduction, Oxygen chemistry, Protein Domains, Protein Multimerization, Rats, Spectrin metabolism, Ankyrins chemistry, Lipoylation physiology
- Abstract
By clustering various ion channels and transporters, ankyrin-G (AnkG) configures the membrane-excitation platforms in neurons and cardiomyocytes. AnkG itself localizes to specific areas on the plasma membrane via s-palmitoylation of Cys. However, the structural mechanism by which AnkG anchors to the membrane is not understood. In this study, we solved the crystal structures of the reduced and oxidized forms of the AnkG s-palmitoylation domain and used multiple long-term coarse-grained molecular dynamics simulations to analyze their membrane association. Here we report that the membrane anchoring of AnkG was facilitated by s-palmitoylation, defining a stable binding interface on the lipid membrane, and that AnkG without s-palmitoylation also preferred to stay near the membrane but did not have a unique binding interface. This suggests that AnkG in the juxtamembrane region is primed to accept lipid modification at Cys, and once that happens AnkG constitutes a rigid structural base upon which a membrane-excitation platform can be assembled.
- Published
- 2016
- Full Text
- View/download PDF
41. Visualizing spatial distribution of alectinib in murine brain using quantitative mass spectrometry imaging.
- Author
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Aikawa H, Hayashi M, Ryu S, Yamashita M, Ohtsuka N, Nishidate M, Fujiwara Y, and Hamada A
- Subjects
- Administration, Oral, Animals, Antineoplastic Agents administration & dosage, Brain blood supply, Carbazoles administration & dosage, Male, Mice, Knockout, Neuroimaging, Piperidines administration & dosage, Tandem Mass Spectrometry, Tissue Distribution, Antineoplastic Agents pharmacokinetics, Brain metabolism, Carbazoles pharmacokinetics, Piperidines pharmacokinetics
- Abstract
In the development of anticancer drugs, drug concentration measurements in the target tissue have been thought to be crucial for predicting drug efficacy and safety. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is commonly used for determination of average drug concentrations; however, complete loss of spatial information in the target tissue occurs. Mass spectrometry imaging (MSI) has been recently applied as an innovative tool for detection of molecular distribution of pharmacological agents in heterogeneous targets. This study examined the intra-brain transitivity of alectinib, a novel anaplastic lymphoma kinase inhibitor, using a combination of matrix-assisted laser desorption ionization-MSI and LC-MS/MS techniques. We first analyzed the pharmacokinetic profiles in FVB mice and then examined the effect of the multidrug resistance protein-1 (MDR1) using Mdr1a/b knockout mice including quantitative distribution of alectinib in the brain. While no differences were observed between the mice for the plasma alectinib concentrations, diffuse alectinib distributions were found in the brain of the Mdr1a/b knockout versus FVB mice. These results indicate the potential for using quantitative MSI for clarifying drug distribution in the brain on a microscopic level, in addition to suggesting a possible use in designing studies for anticancer drug development and translational research.
- Published
- 2016
- Full Text
- View/download PDF
42. Accumulation of p53 via down-regulation of UBE2D family genes is a critical pathway for cadmium-induced renal toxicity.
- Author
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Lee JY, Tokumoto M, Fujiwara Y, Hasegawa T, Seko Y, Shimada A, and Satoh M
- Subjects
- Animals, Apoptosis Regulatory Proteins metabolism, Base Sequence, Blotting, Western, Cell Line, Female, Forkhead Transcription Factors antagonists & inhibitors, Forkhead Transcription Factors genetics, Forkhead Transcription Factors metabolism, Humans, Kidney drug effects, Kidney metabolism, Kidney pathology, Mice, Mice, Inbred C57BL, Microscopy, Fluorescence, Proto-Oncogene Proteins metabolism, RNA Interference, RNA, Small Interfering metabolism, Real-Time Polymerase Chain Reaction, Tumor Suppressor Protein p53 antagonists & inhibitors, Tumor Suppressor Protein p53 genetics, Ubiquitin-Conjugating Enzymes antagonists & inhibitors, Ubiquitin-Conjugating Enzymes genetics, YY1 Transcription Factor antagonists & inhibitors, YY1 Transcription Factor genetics, YY1 Transcription Factor metabolism, bcl-2-Associated X Protein metabolism, Apoptosis drug effects, Cadmium toxicity, Down-Regulation drug effects, Tumor Suppressor Protein p53 metabolism, Ubiquitin-Conjugating Enzymes metabolism
- Abstract
Chronic cadmium (Cd) exposure can induce renal toxicity. In Cd renal toxicity, p53 is thought to be involved. Our previous studies showed that Cd down-regulated gene expression of the UBE2D (ubiquitin-conjugating enzyme E2D) family members. Here, we aimed to define the association between UBE2D family members and p53-dependent apoptosis in human proximal tubular cells (HK-2 cells) treated with Cd. Cd increased intracellular p53 protein levels and decreased UBE2D2 and UBE2D4 gene expression via inhibition of YY1 and FOXF1 transcription factor activities. Double knockdown of UBE2D2 and UBE2D4 caused an increase in p53 protein levels, and knockdown of p53 attenuated not only Cd-induced apoptosis, but also Cd-induced apoptosis-related gene expression (BAX and PUMA). Additionally, the mice exposed to Cd for 6 months resulted in increased levels of p53 and induction of apoptosis in proximal tubular cells. These findings suggest that down-regulation of UBE2D family genes followed by accumulation of p53 in proximal tubular cells is an important mechanism for Cd-induced renal toxicity.
- Published
- 2016
- Full Text
- View/download PDF
43. Deep-sea whale fall fauna from the Atlantic resembles that of the Pacific Ocean.
- Author
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Sumida PY, Alfaro-Lucas JM, Shimabukuro M, Kitazato H, Perez JA, Soares-Gomes A, Toyofuku T, Lima AO, Ara K, and Fujiwara Y
- Subjects
- Animals, Aquatic Organisms classification, Aquatic Organisms physiology, Atlantic Ocean, Biodiversity, Bone and Bones, Brazil, Ecosystem, Pacific Ocean, Species Specificity, Animal Feed analysis, Meat analysis, Minke Whale physiology
- Abstract
Whale carcasses create remarkable habitats in the deep-sea by producing concentrated sources of organic matter for a food-deprived biota as well as places of evolutionary novelty and biodiversity. Although many of the faunal patterns on whale falls have already been described, the biogeography of these communities is still poorly known especially from basins other than the NE Pacific Ocean. The present work describes the community composition of the deepest natural whale carcass described to date found at 4204 m depth on Southwest Atlantic Ocean with manned submersible Shinkai 6500. This is the first record of a natural whale fall in the deep Atlantic Ocean. The skeleton belonged to an Antarctic Minke whale composed of only nine caudal vertebrae, whose degradation state suggests it was on the bottom for 5-10 years. The fauna consisted mainly of galatheid crabs, a new species of the snail Rubyspira and polychaete worms, including a new Osedax species. Most of the 41 species found in the carcass are new to science, with several genera shared with NE Pacific whale falls and vent and seep ecosystems. This similarity suggests the whale-fall fauna is widespread and has dispersed in a stepping stone fashion, deeply influencing its evolutionary history.
- Published
- 2016
- Full Text
- View/download PDF
44. Utilization of native oxygen in Eu(RE)-doped GaN for enabling device compatibility in optoelectronic applications.
- Author
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Mitchell B, Timmerman D, Poplawsky J, Zhu W, Lee D, Wakamatsu R, Takatsu J, Matsuda M, Guo W, Lorenz K, Alves E, Koizumi A, Dierolf V, and Fujiwara Y
- Abstract
The detrimental influence of oxygen on the performance and reliability of V/III nitride based devices is well known. However, the influence of oxygen on the nature of the incorporation of other co-dopants, such as rare earth ions, has been largely overlooked in GaN. Here, we report the first comprehensive study of the critical role that oxygen has on Eu in GaN, as well as atomic scale observation of diffusion and local concentration of both atoms in the crystal lattice. We find that oxygen plays an integral role in the location, stability, and local defect structure around the Eu ions that were doped into the GaN host. Although the availability of oxygen is essential for these properties, it renders the material incompatible with GaN-based devices. However, the utilization of the normally occurring oxygen in GaN is promoted through structural manipulation, reducing its concentration by 2 orders of magnitude, while maintaining both the material quality and the favorable optical properties of the Eu ions. These findings open the way for full integration of RE dopants for optoelectronic functionalities in the existing GaN platform.
- Published
- 2016
- Full Text
- View/download PDF
45. Optical excitation and external photoluminescence quantum efficiency of Eu³⁺ in GaN.
- Author
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de Boer WD, McGonigle C, Gregorkiewicz T, Fujiwara Y, Tanabe S, and Stallinga P
- Abstract
We investigate photoluminescence of Eu-related emission in a GaN host consisting of thin layers grown by organometallic vapor-phase epitaxy. By comparing it with a reference sample of Eu-doped Y₂O₃, we find that the fraction of Eu(3+) ions that can emit light upon optical excitation is of the order of 1%. We also measure the quantum yield of the Eu-related photoluminescence and find this to reach (~10%) and (~3%) under continuous wave and pulsed excitation, respectively.
- Published
- 2014
- Full Text
- View/download PDF
46. Promotion of atherosclerosis by Helicobacter cinaedi infection that involves macrophage-driven proinflammatory responses.
- Author
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Khan S, Rahman HN, Okamoto T, Matsunaga T, Fujiwara Y, Sawa T, Yoshitake J, Ono K, Ahmed KA, Rahaman MM, Oyama K, Takeya M, Ida T, Kawamura Y, Fujii S, and Akaike T
- Subjects
- Animals, Aorta immunology, Aorta microbiology, Aorta pathology, Atherosclerosis pathology, Cardiovascular Diseases pathology, Cell Differentiation immunology, Cells, Cultured, DNA, Bacterial analysis, Foam Cells immunology, Helicobacter Infections microbiology, Helicobacter pylori genetics, Helicobacter pylori pathogenicity, Hyperlipidemias microbiology, Inflammation immunology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Monocytes immunology, Neutrophils immunology, Nitric Oxide Synthase Type III genetics, RNA, Bacterial analysis, Receptors, LDL biosynthesis, Atherosclerosis microbiology, Cardiovascular Diseases microbiology, Helicobacter Infections immunology, Helicobacter pylori immunology, Macrophages immunology
- Abstract
Helicobacter cinaedi is the most common enterohepatic Helicobacter species that causes bacteremia in humans, but its pathogenicity is unclear. Here, we investigated the possible association of H. cinaedi with atherosclerosis in vivo and in vitro. We found that H. cinaedi infection significantly enhanced atherosclerosis in hyperlipidaemic mice. Aortic root lesions in infected mice showed increased accumulation of neutrophils and F4/80(+) foam cells, which was due, at least partly, to bacteria-mediated increased expression of proinflammatory genes. Although infection was asymptomatic, detection of cytolethal distending toxin RNA of H. cinaedi indicated aorta infection. H. cinaedi infection altered expression of cholesterol receptors and transporters in cultured macrophages and caused foam cell formation. Also, infection induced differentiation of THP-1 monocytes. These data provide the first evidence of a pathogenic role of H. cinaedi in atherosclerosis in experimental models, thereby justifying additional investigations of the possible role of enterohepatic Helicobacter spp. in atherosclerosis and cardiovascular disease.
- Published
- 2014
- Full Text
- View/download PDF
47. Induced magnetic moment of Eu(3+) ions in GaN.
- Author
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Kachkanov V, Wallace MJ, van der Laan G, Dhesi SS, Cavill SA, Fujiwara Y, and O'Donnell KP
- Abstract
Magnetic semiconductors with coupled magnetic and electronic properties are of high technological and fundamental importance. Rare-earth elements can be used to introduce magnetic moments associated with the uncompensated spin of 4f-electrons into the semiconductor hosts. The luminescence produced by rare-earth doped semiconductors also attracts considerable interest due to the possibility of electrical excitation of characteristic sharp emission lines from intra 4f-shell transitions. Recently, electroluminescence of Eu-doped GaN in current-injection mode was demonstrated in p-n junction diode structures grown by organometallic vapour phase epitaxy. Unlike most other trivalent rare-earth ions, Eu(3+) ions possess no magnetic moment in the ground state. Here we report the detection of an induced magnetic moment of Eu(3+) ions in GaN which is associated with the (7)F(2) final state of (5)D(0)→(7)F(2) optical transitions emitting at 622 nm. The prospect of controlling magnetic moments electrically or optically will lead to the development of novel magneto-optic devices.
- Published
- 2012
- Full Text
- View/download PDF
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