Updated on 2024/03/29

写真a

 
KIJIMA Yasufumi
 
Organization
University Medical and Dental Hospital Orthopedic Surgery Assistant Professor
Title
Assistant Professor
External link

Degree

  • 博士(医学) ( 2019.9 )

Research History

  • Niigata University   University Medical and Dental Hospital Orthopedic Surgery   Assistant Professor

    2020.4

 

Papers

  • Bone Histomorphometry of Femoral Head Cancellous Bone in Patients Who Underwent Total Hip Arthroplasties due to Destructive Hip in Rheumatoid Arthritis.

    Yasufumi Kijima, Naoki Kondo, Go Okumura, Naoto Endo

    Acta medica Okayama   75 ( 2 )   125 - 131   2021.4

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    Language:English   Publishing type:Research paper (scientific journal)  

    Rheumatoid arthritis (RA) affects the hip joints. The microarchitecture of the cancellous bone in RA-affected hip joints has been unclear. Here we investigated the bone metabolism changes in the subcapital cancellous bone of destructive hips of RA patients (n=26 patients; 28 hip joints) which were classified by Larsen grade on X-ray into the groups: destructive hip (Des) (Larsen grade IV, n=18) and neck fracture (Fx) (Larsen grade 0 or 1, n=10). The femoral heads of the Des-group showed significantly higher trabecular thickness versus those of the Fx-group (179±30.8 vs. 151±23.5 μm, p=0.02). The Des-group had significantly higher osteoid volume/tissue volume (OV/TV) and osteoid volume/bone volume (OV/BV) ratios than the Fx-group (OV/TV: 0.72±0.70% vs. 0.27±0.32%, p=0.028; OV/BV: 2.96±2.85% vs. 1.24±1.31%, p=0.039). The osteoblast and osteoclast surface areas of the Des-group were remarkably higher than those of the Fx-group (9.80±10.9 vs. 0.15±0.15%, p=0.0005; 0.34±0.48 vs. 0.06±0.06%, p=0.0285, respectively). The T-scores of hip (femoral neck) bone mineral density (BMD) of the Fx-group were significantly lower versus those of the Des-group (-3.1±0.76 vs. -1.6±1.17, p<0.01). Increased osteoid and resorption parameters and higher femoral neck BMD demonstrate a high bone-turnover state in response to destructive changes in the hips of RA patients.

    DOI: 10.18926/AMO/61878

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  • The JNK pathway represents a novel target in the treatment of rheumatoid arthritis through the suppression of MMP-3. International journal

    Tomotake Kanai, Naoki Kondo, Masayasu Okada, Hiroshige Sano, Go Okumura, Yasufumi Kijima, Akira Ogose, Hiroyuki Kawashima, Naoto Endo

    Journal of orthopaedic surgery and research   15 ( 1 )   87 - 87   2020.3

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    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND AND AIM: The pathophysiology of rheumatoid arthritis (RA) is characterized by excess production of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) by neutrophils and macrophages in synovium. Additionally, these cytokines promote the production of reactive oxygen species (ROS), and increased production of matrix metalloproteinases (MMPs), including MMP-3, in synoviocytes that result in joint destruction. There is limited information on how proteolytic enzymes such as MMP-3 can be regulated. We evaluated the effect of the antioxidant N-acetylcysteine (NAC) on RA and identified the relationship between the c-Jun N terminal kinase (JNK) pathway and MMP-3. We hypothesized that elucidating this relationship would lead to novel therapeutic approaches to RA treatment and management. METHODS: We investigated the effect of administering a low dose (1000 μM or less) of an antioxidant (NAC) to human rheumatoid fibroblast-like synoviocytes (MH7A cells). We also investigated the response of antioxidant genes such as nuclear factor erythroid -derived 2-related factor 2 (Nrf2) and Sequestosome 1 (p62). The influence of MMP-3 expression on the JNK pathway leading to joint destruction and the mechanisms underlying this relationship were investigated through primary dispersion culture cells collected from the synovial membranes of RA patients, consisting of rheumatoid arthritis-fibroblast-like synoviocytes (RA-FLS). RESULTS: Low-dose NAC (1000 μM) increased the expression of Nrf2 and phospho-p62 in MH7A cells, activating antioxidant genes, suppressing the expression of MMP-3, and inhibiting the phosphorylation of JNK. ROS, MMP-3 expression, and IL-6 was suppressed by administering 30 μM of SP600125 (a JNK inhibitor) in MH7A cells. Furthermore, the administration of SP600125 (30 μM) to RA-FLS suppressed MMP-3. CONCLUSIONS: We demonstrated the existence of an MMP-3 suppression mechanism that utilizes the JNK pathway in RA-FLS. We consider that the JNK pathway could be a target for future RA therapies.

    DOI: 10.1186/s13018-020-01595-9

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  • Evidence for Ongoing Modeling-Based Bone Formation in Human Femoral Head Trabeculae via Forming Minimodeling Structures: A Study in Patients with Fractures and Arthritis. International journal

    Hiroshige Sano, Naoki Kondo, Taketoshi Shimakura, Junichi Fujisawa, Yasufumi Kijima, Tomotake Kanai, Kenneth E S Poole, Noriaki Yamamoto, Hideaki E Takahashi, Naoto Endo

    Frontiers in endocrinology   9   88 - 88   2018

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    Language:English   Publishing type:Research paper (scientific journal)  

    Bone modeling is a biological process of bone formation that adapts bone size and shape to mechanical loads, especially during childhood and adolescence. Bone modeling in cortical bone can be easily detected using sequential radiographic images, while its assessment in trabecular bone is challenging. Here, we performed histomorphometric analysis in 21 bone specimens from biopsies collected during hip arthroplasty, and we proposed the criteria for histologically identifying an active modeling-based bone formation, which we call a "forming minimodeling structure" (FMiS). Evidence of FMiSs was found in 9 of 20 specimens (45%). In histomorphometric analysis, bone volume was significant higher in specimens displaying FMiSs compared with the specimens without these structures (BV/TV, 31.7 ± 10.2 vs. 23.1 ± 3.9%; p < 0.05). Osteoid parameters were raised in FMiS-containing bone specimens (OV/BV, 2.1 ± 1.6 vs. 0.6 ± 0.3%; p < 0.001, OS/BS, 23.6 ± 15.5 vs. 7.6 ± 4.2%; p < 0.001, and O.Th, 7.4 µm ± 2.0 vs. 5.2 ± 1.0; p < 0.05). Our results showed that the modeling-based bone formation on trabecular bone surfaces occurs even during adulthood. As FMiSs can represent histological evidence of modeling-based bone formation, understanding of this physiology in relation to bone homeostasis is crucial.

    DOI: 10.3389/fendo.2018.00088

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