Publications by authors named "Takahi K"

Background: In end-stage arthritis indicated for total ankle arthroplasty (TAA), full-thickness cartilage damage, subchondral bone defect/shaving, and fluttering of the talar dome occur, shortening the distance between the tibial and talar insertions of ligaments and leading to laxity of ligaments surrounding the ankle joint. Under such conditions, medial ligaments (including the deltoid ligament) would not be expected to function properly. To stabilize the ankle joint during the stance phase, medial ligament function under tension is important.

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  • The study investigates how new antirheumatic drugs affect the characteristics of lymphoproliferative disorder (LPD) in rheumatoid arthritis (RA) patients, using data from 53 hospitals in Japan between 1999 and 2021.
  • A total of 752 patients with RA-associated LPD were compared to 770 with sporadic LPD, revealing notable differences in their clinical features and the impact of various drug combinations.
  • The findings suggest that medications taken before LPD onset may alter its characteristics, and recommend tocilizumab (TCZ) as a better treatment option after LPD has developed.
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  • - This study explored the safety and feasibility of starting full weight-bearing and gait exercises soon after cemented total ankle arthroplasty (TAA) using a modified approach, instead of the conventional wait for wound healing.
  • - Researchers retrospectively evaluated 23 ankles and divided them into three groups based on rehabilitation protocols, finding no wound-related complications even with early weight-bearing and quicker recovery times.
  • - Results indicated that early mobilization and weight-bearing (starting as early as 7 days post-surgery) significantly reduced hospitalization from 35-38 days to just 24 days, suggesting potential improvements in TAA rehabilitation practices.
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Background: According to the conventional postoperative procedure after total ankle arthroplasty (TAA), mobilization is currently started after completion of wound healing. To investigate the possibility of expediting rehabilitation, this study evaluated the feasibility and safety of early mobilization of dorsiflexion after cemented TAA utilizing a modified antero-lateral approach.

Materials And Methods: This retrospective, observational study investigated 14 consecutive ankles that had received cemented TAA.

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Hydrolysis of the phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2) at the cell membrane induces the release of inositol 1,4,5-trisphosphate (IP3) into the cytoplasm and diffusion of diacylglycerol (DAG) through the membrane, respectively. Release of IP3 subsequently increases Ca2+ levels in the cytoplasm, which results in activation of protein kinase C α (PKCα) by Ca2+ and DAG, and finally the translocation of PKCα from the cytoplasm to the membrane. In this study, we developed a metabolic reaction-diffusion framework to simulate PKCα translocation via PIP2 hydrolysis in an endothelial cell.

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  • The study investigated the effects of follow-on therapies for postmenopausal osteoporosis patients after they discontinued denosumab (DMAb), comparing different treatments like raloxifene (RAL), bisphosphonates (BP), and zoledronate (ZOL).
  • Over 1.5 years post-DMAb, bone mineral density (BMD) changes were observed, with raloxifene showing significant declines in both lumbar spine and femoral neck BMD, while ZOL notably reduced fracture incidence.
  • Findings suggest that the choice of follow-on therapy after DMAb discontinuation is critical, particularly highlighting ZOL's effectiveness, but further research is needed to fully understand these outcomes.
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Background: When soft tissue balance is not acceptable at total ankle arthroplasty (TAA) for rheumatoid varus deformity, medial malleolar osteotomy has been performed. At the same time, the shape of the ankle joint changes after soft tissue balancing with such an osteotomy, however there is few information for the radiographic findings after the osteotomy. Thus, radiographic changes in the coronal view of such cases were investigated.

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Objectives: Tocilizumab (TCZ) shows good retention in patients with rheumatoid arthritis (RA), but no previous reports demonstrated hopeful treatment options against inadequate response to TCZ. Tacrolimus (TAC) has proved to show efficacy against inadequate response to tumor necrosis factor alpha inhibitors, yet its add-on effects on TCZ remain unknown.

Methods: Twenty patients with RA (17 women, age 58.

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Vaccination against Streptococcus pneumoniae is recommended for rheumatoid arthritis (RA) patients receiving immunosuppressive treatments. The objective of this study was to evaluate the humoral response to 23-valent pneumococcal polysaccharide vaccination (PPSV23) in RA patients receiving methotrexate (MTX) alone or in combination with a tumor necrosis factor inhibitor, golimumab (GOM).PPSV23 was given to 114 RA patients, who were classified into three groups: RA control (n = 35), MTX alone (n = 55), and GOM + MTX (n = 24).

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  • The study investigates the immune response of rheumatoid arthritis (RA) patients receiving abatacept (ABT) after vaccination with the 23-valent pneumococcal polysaccharide (PPSV23).
  • Patients receiving PPSV23 showed significant increases in antibody levels across all treatment groups, but those on ABT had lower specific IgG responses.
  • No significant adverse effects were reported, indicating that while immune responses varied, the functionality of antibodies remained consistent across groups.
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Purpose: To evaluate disease activity, knee function, and walking ability of patients with rheumatoid arthritis (RA) over 10 years after total knee arthroplasty (TKA).

Methods: Four men and 26 women (mean age, 59.9 years) underwent 42 TKAs for RA with a mean duration of 151.

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Purpose: To evaluate the clinical outcomes of corrective osteotomy and ligament repair for longstanding radial collateral ligament tears of the proximal interphalangeal (PIP) joint.

Methods: We retrospectively evaluated 4 patients with 5 longstanding tears in the radial collateral ligaments of the PIP joints. The average age at the time of surgery was 51 years (range, 40-62 y).

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We report a case of sudden onset of late infection after TKA inflamed by anti-TNFalpha therapy, Infliximab, in a 54-year-old woman with RA. Infliximab therapy was started 3 years and 8 months after TKAs as a result of multiple arthritides showing high inflammation of RA. One week after the third administration of Infliximab, the patient suffered sudden knee pain and infectious clinical symptoms, and bacteria (MSSA) were detected by joint effusion culture.

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FR167653 is a potent inhibitor of p38 MAP Kinase and inhibits TNF-alpha and IL-1beta production in inflammatory cells. In this study we investigated the effect of FR167653 on CIA. CIA rats were subcutaneously injected with FR167653 (32 mg/kg/day) starting on the day of the booster injection and after the onset of arthritis in the prophylactic and therapeutic treatment groups, respectively.

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Objectives: Nurse-like stromal cells (NLC) in synovia and bone marrow of patients with rheumatoid arthritis (RA) can support pseudoemperipolesis, protect from apoptosis and enhance immunoglobulin production of peripheral blood B cells isolated from healthy individuals, suggesting the profound contribution of hyperactivation of B cells in RA. In the course of establishing RA-NLC from RA patients, we observed the growth of B cells in the presence of RA-NLC.

Methods: We cloned B cells from the synovium or bone marrow of RA patients using the limiting dilution technique.

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In iliac bone marrow the absolute number of mononuclear cells (MNCs) was increased in RA patients compared with the non-RA controls. In CD8 positive cell and myeloid cell fractions, significant differences were recognized between RA patients and non-RA controls. The presence of abnormal myeloid lineage cells in epiphyseal bone marrow adjacent to joints affected with severe RA was shown.

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Abnormalities of the epiphyseal growth plate that occur in collagen-induced arthritis (CIA) were studied. CIA was induced in 6-week-old Lewis rats by immunization with type II collagen. Radiographic examination revealed the early closure of the epiphyseal growth plate with growth retardation of the femur and tibia.

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Objective: To investigate the morphology and function of multinucleated bone-resorbing giant cells derived from CD14-positive cells in the synovial fluids (SF) of patients with rheumatoid arthritis (RA) or osteoarthritis (OA).

Methods: CD14-positive cells were obtained by magnetic-activated cell sorting of primary cultures of mononuclear cells from the SF. Multinucleated bone-resorbing giant cells were induced from the CD14-positive cells in the presence or absence of cytokines.

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Objective: FR167653 is a potent inhibitor of p38 mitogen-activated protein kinase (MAPK) and inhibits tumor necrosis factor alpha (TNFalpha) and interleukin-1 beta (IL-1 beta) production in inflammatory cells. In this study we investigated the effect of FR167653 on collagen-induced arthritis (CIA).

Methods: Rats with CIA were subcutaneously injected with FR167653 (32 mg/kg/day) starting on the day of the booster injection (day 7) in the prophylactic treatment group and after the onset of arthritis (day 21) in the therapeutic treatment group.

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Nurse-like stromal cell lines from the synovial tissue of patients with rheumatoid arthritis (RA-SNC) produce, on coculture with lymphocytes, large amounts of proinflammatory cytokines. In the present paper, we analyze the molecular events necessary for the induction of cytokine release from RA-SNC cells, and particularly the roles played by cell adhesion and the transmigration (also known as pseudoemperipolesis) of lymphocytes. For this purpose, the effects of various mAbs on the binding and transmigration of a human B-cell line, MC/car, were examined using a cloned RA-SNC line, RA-SNC77.

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Objective: To investigate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) at sites of joint destruction in rheumatoid arthritis (RA) and to correlate it with the production of matrix metalloproteinases (MMPs).

Methods: Reverse transcription-polymerase chain reaction was performed to study the existence of EMMPRIN in synovial tissue derived from RA and osteoarthritis (OA) patients. In situ hybridization with a human complementary DNA specific for EMMPRIN and immunohistochemistry were performed to characterize the EMMPRIN-expressing cells at sites of joint destruction, including bone.

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Objective: We previously described abnormalities in the bone marrow of patients with rheumatoid arthritis (RA), but were able to shed little light on the pathogenic roles of inflammatory cytokines and proteinases in joint destruction in the subchondral region in RA. This is the first report to describe the co-localization of cytokines and proteinases in this area.

Methods: Decalcified paraffin-embedded sections from 10 patients with RA and five patients with osteoarthritis (OA) were examined for the immunolocalization of cathepsins B, K and L and the localization of messenger RNAs for interleukin 1beta (IL-1beta), tumour necrosis factor alpha (TNF-alpha) and matrix metalloproteinase 9 (MMP-9).

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Objective: Numerous cytokines are expressed in lesions of synovial hyperplasia of patients with rheumatoid arthritis (RA), and their pathophysiological contributions have been the subject of speculation. These genes are regulated by the transcription factor NFkappaB which in turn is activated by tumour necrosis factor-alpha (TNF-alpha) and cytokines. In this study we examined the inhibition of the production of pro-inflammatory cytokines, adhesion molecule and matrix metalloproteinase (MMP) from synovial tissue of patients with RA by the introduction of synthetic double-stranded DNA with high affinity for the NFkappaB binding site.

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