Publications by authors named "Ryota Chijimatsu"

Unlabelled: Adipose-derived stem cells (ASCs) and their small extracellular vesicles (sEVs) hold significant potential for regenerative medicine due to their tissue repair capabilities. The microRNA (miRNA) content in sEVs varies depending on ASC status; however, the effects of aging and cell passage on miRNA profiles remain unclear. In this study, we examined the effects of donor age and cell expansion on ASC characteristics and transcriptome using ASCs obtained from three young and three old donors.

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  • Idiopathic multicentric Castleman disease (iMCD) is a subtype of Castleman disease that is not linked to KSHV/HHV8 and is categorized into three types: iMCD-IPL, iMCD-TAFRO, and iMCD-NOS.
  • The primary treatment is IL-6 inhibitors, yet patients with iMCD-TAFRO and NOS often show resistance, indicating the influence of other cytokines in their pathology.
  • A transcriptome analysis revealed increased expression of various cytokine-related genes in iMCD-TAFRO/NOS, suggesting enhanced inflammatory signaling pathways, particularly the JAK-STAT and MAPK pathways, contributing to a potential cytokine storm.
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  • Disulfiram (DSF), an anti-alcoholism medication, shows potential in preventing bone loss by inhibiting osteoclast differentiation in osteoporotic mice.
  • Research utilized techniques like microcomputed tomography and single-cell RNA sequencing to study DSF effects on bone and osteoclast precursor cells.
  • Results indicated that DSF not only reduced the number of osteoclasts but did so without negatively impacting osteoblast formation, suggesting its possible role in osteoporosis treatment.
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Background: Janus kinase (JAK) inhibitors, such as baricitinib, are widely used to treat rheumatoid arthritis (RA). Clinical studies show that baricitinib is more effective at reducing pain than other similar drugs. Here, we aimed to elucidate the molecular mechanisms underlying the pain relief conferred by baricitinib, using a mouse model of arthritis.

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Gallbladder cancer incidence has been increasing globally, and it remains challenging to expect long prognosis with the current systemic chemotherapy. We identified a novel nucleic acid-mediated therapeutic target against gallbladder cancer by using innovative organoid-based gallbladder cancer models generated from ; mice. Using comprehensive microRNA expression analyses and a bioinformatics approach, we identified significant microRNA-34a-5p downregulation in both murine gallbladder cancer organoids and resected human gallbladder cancer specimens.

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Synovial sarcoma (SS), a rare subtype of soft-tissue sarcoma distinguished by expression of the fusion gene SS18-SSX, predominantly affects the extremities of young patients. Existing anticancer drugs have limited efficacy against this malignancy, necessitating the development of innovative therapeutic approaches. Given the established role of SS18-SSX in epigenetic regulation, we focused on bromodomain and extra-terminal domain protein (BET) inhibitors and epigenetic agents.

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  • Both mesenchymal stromal cells (MSC) and induced pluripotent stem cells (iPSC) can help repair damaged connective tissues.
  • A study showed that hybrid implants combining human MSC and iPSC effectively filled and integrated osteochondral defects in rats.
  • The MSC component is crucial for success, promoting repair, adhesion, and blood vessel growth at the injury site, suggesting these hybrid implants could be a promising treatment for complex injuries in the future.
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The distribution and clinical impact of cell-of-origin (COO) subtypes of diffuse large B-cell lymphoma (DLBCL) outside Western countries remain unknown. Recent literature also suggests that there is an additional COO subtype associated with the germinal center dark zone (DZ) that warrants wider validation to generalize clinical relevance. Here, we assembled a cohort of Japanese patients with untreated DLBCL and determined the refined COO subtypes, which include the DZ signature (DZsig), using the NanoString DLBCL90 assay.

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  • Clear cell sarcoma (CCS) is a rare and aggressive cancer with no effective treatment, driven by a fusion gene that researchers targeted in this study.
  • High-throughput drug screening identified vorinostat, a histone deacetylase inhibitor, as effective in reducing the fusion gene’s expression, though it only slightly altered the chromatin structure around the gene.
  • Combining vorinostat with the BRD4 inhibitor JQ1 showed a synergistic effect in suppressing CCS cell proliferation, highlighting a new therapeutic strategy for treating tumors linked to fusion genes.
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Background: No effective therapies have yet been established for liver regeneration in liver failure. Autologous skeletal myoblast cell sheet transplantation has been proven to improve cardiac function in patients with heart failure, and one of the mechanisms has been reported to be a paracrine effect by various growth factors associated with liver regeneration. Therefore, the present study focused on the effect of myoblast cells on liver regeneration in vitro and in vivo.

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Although the skeleton is essential for locomotion, endocrine functions, and hematopoiesis, the molecular mechanisms of human skeletal development remain to be elucidated. Here, we introduce an integrative method to model human skeletal development by combining in vitro sclerotome induction from human pluripotent stem cells and in vivo endochondral bone formation by implanting the sclerotome beneath the renal capsules of immunodeficient mice. Histological and scRNA-seq analyses reveal that the induced bones recapitulate endochondral ossification and are composed of human skeletal cells and mouse circulatory cells.

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Background: Tissue-resident memory T (Trm) cells are associated with cytotoxicity not only in viral infection and autoimmune disease pathologies but also in many cancers. Tumour-infiltrating CD103 Trm cells predominantly comprise CD8 T cells that express cytotoxic activation and immune checkpoint molecules called exhausted markers. This study aimed to investigate the role of Trm in colorectal cancer (CRC) and characterise the cancer-specific Trm.

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The Runt-related transcription factor (Runx) family plays various roles in the homeostasis of cartilage. Here, we examined the role of Runx2 and Runx3 for osteoarthritis development in vivo and in vitro. Runx3-knockout mice exhibited accelerated osteoarthritis following surgical induction, accompanied by decreased expression of lubricin and aggrecan.

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  • Ectopic endochondral ossification in tendons and ligaments results from repetitive stress or inflammation, and tendon stem/progenitor cells (TSPCs) play a role in tissue repair, with some expressing lubricin (PRG4).
  • Research identified a specific cluster of TSPCs that express R-spondin 2 (RSPO2), a WNT signaling activator, which helps maintain these cells in an undifferentiated state.
  • In experiments, RSPO2 overexpression reduced ectopic ossification in mouse models by inhibiting chondrogenic differentiation, and lower RSPO2 levels were found in patients with specific ligament ossification compared to those
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  • Researchers created a comprehensive single-cell atlas of pancreatic ductal adenocarcinoma (PDAC) by analyzing data from over 70 samples and more than 130,000 cells, enhancing understanding of the tumor's complexity and environment.
  • The application of this atlas helped reanalyze existing bulk transcriptomic studies and revealed key relationships between different cell types, indicating that high levels of tumor cells and fibroblasts are linked to worse patient outcomes.
  • The study identified distinct tumor clusters and their interactions with various fibroblast subtypes, providing insights into the signaling pathways that contribute to the heterogeneity within PDAC and offering a valuable reference for future research.
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In pancreatic cancer, methyltransferase-like 3 (METTL3), a N(6)-methyladenosine (m6A) methyltransferase, has a favorable effect on tumors and is a risk factor for patients' prognosis. However, the details of what genes are regulated by METTL3 remain unknown. Several RNAs are methylated, and what genes are favored in pancreatic cancer remains unclear.

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Unlabelled: Adipose-derived stem cells (ASCs) are an attractive cell source for cell therapy. Despite the increasing number of clinical applications, the methodology for ASC isolation is not optimized for every individual. In this study, we developed an effective material to stabilize explant cultures from small-fragment adipose tissues.

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Nematodes, such as , have been instrumental to the study of cancer. Recently, their significance as powerful cancer biodiagnostic tools has emerged, but also for mechanism analysis and drug discovery. It is expected that nematode-applied technology will facilitate research and development on the human tumor microenvironment.

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Introduction: Cell therapy using adipose-derived mesenchymal stem cells (ASCs) is a promising avenue of regenerative medicine for the treatment of various diseases. It has been considered that ASCs exert their therapeutic effects through the secretion of multiple factors that are critical for tissue remodeling or the suppression of inflammation. Recently, conditioned medium (CM) from ASCs that contains a complex of secreted factors has received attention as a cost-effective alternative to cell therapy.

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Similar to epigenetic DNA modification, RNA can be methylated and altered for stability and processing. RNA modifications, namely, epitranscriptomes, involve the following three functions: writing, erasing, and reading of marks. Methods for measurement and position detection are useful for the assessment of cellular function and human disease biomarkers.

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Although cancer precision medicine has improved diagnosis and therapy, refractory cancers such as pancreatic cancer remain to be challenging targets. Clinical sequencing has identified the significant alterations in driver genes and traced their clonal evolutions. Recent studies indicated that the tumor microenvironment elicits alterations in cancer metabolism, although its involvement in the cause and development of genomic alterations has not been established.

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Introduction: A disintegrin and metalloproteinase 17 (Adam17), also known as TNFα-converting enzyme (Tace), is a membrane-anchored protein involved in shedding of TNF, IL-6 receptor, ligands of epidermal growth factor receptor (EGFR), and Notch receptor. This study aimed to examine the role of Adam17 in adult articular cartilage and osteoarthritis (OA) pathophysiology.

Materials And Methods: Adam17 expression was examined in mouse knee joints during OA development.

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As cancer is a genetic disease, methylation defines a biologically malignant phenotype of cancer in the association of one-carbon metabolism-dependent S-adenosylmethionine (SAM) as a methyl donor in each cell. Methylated substances are involved in intracellular metabolism, but via intercellular communication, some of these can also be secreted to affect other substances. Although metabolic analysis at the single-cell level remains challenging, studying the "methylosystem" (i.

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  • Large bone defects from trauma or tumors are a tough challenge in orthopedic surgery, often requiring artificial bone due to limited autograft options.
  • Current artificial bones mainly serve as fillers and lack the ability to promote bone growth, which limits their effectiveness.
  • This study shows that treating artificial bone surfaces with low-pressure plasma can enhance their properties, leading to better cell adhesion and bone regeneration, suggesting a new approach to improve artificial bone use in surgery.
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