Publications by authors named "Yoji Komiya"

COVID-19, caused by SARS-CoV-2 infection, results in irreversible or fatal lung injury. We assumed that necroptosis of virus-infected alveolar epithelial cells (AEC) could promote local inflammation and further lung injury in COVID-19. Since CD8+ lymphocytes induced AEC cell death via cytotoxic molecules such as FAS ligands, we examined the involvement of FAS-mediated cell death in COVID-19 patients and murine COVID-19 model.

View Article and Find Full Text PDF

The severity of COVID-19 has been reported to differ among SARS-CoV-2 mutant variants. The overactivation of macrophages is involved in severe COVID-19, yet the effects of SARS-CoV-2 mutations on macrophages remain poorly understood. To clarify the effects, we examined whether mutations of spike proteins (S-proteins) affect macrophage activation.

View Article and Find Full Text PDF

Obesity has been recognized as one of the most significant risk factors for the deterioration and mortality associated with COVID-19, but the significance of obesity itself differs among ethnicity. Multifactored analysis of our single institute-based retrospective cohort revealed that high visceral adipose tissue (VAT) burden, but not other obesity-associated markers, was related to accelerated inflammatory responses and the mortality of Japanese COVID-19 patients. To elucidate the mechanisms how VAT-dominant obesity induces severe inflammation after severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, we infected two different strains of obese mice, C57BL/6JHamSlc-ob/ob (ob/ob), C57BLKS/J-db/db (db/db), genetically impaired in the leptin ligand and receptor, respectively, and control C57BL/6 mice with mouse-adapted SARS-CoV-2.

View Article and Find Full Text PDF
Article Synopsis
  • The study aimed to explore factors affecting physical function in older rheumatoid arthritis patients (ages 75-84) using the Health Assessment Questionnaire Disability Index (HAQ-DI).
  • Data from over 15,000 patients were analyzed, focusing on 3,708 individuals aged 55-84, revealing that old-old patients had lower methotrexate use and higher glucocorticoid use compared to younger groups.
  • Findings indicated that higher disease activity and certain medications were linked to poorer physical function, with achieving remission being crucial for improving physical health in these patients.
View Article and Find Full Text PDF

Objective: Synovial fibroblasts (SFs) in rheumatoid arthritis (RA) and osteoarthritis (OA) play biphasic roles in joint destruction and regeneration of bone/cartilage as mesenchymal stem cells (MSCs). Although MSCs contribute to joint homeostasis, such function is impaired in arthritic joints. We have identified functionally distinct three SF subsets characterized by the expression of CD34 and THY1 as follows: CD34THY1, CD34THY1, and CD34THY1.

View Article and Find Full Text PDF

A 57-year-old woman was admitted to our hospital because of a high fever, anemia, and hyperferritinemia. Since a bone marrow examination revealed hemophagocytosis, she was diagnosed with hemophagocytic syndrome (HPS). During treatment of HPS, a heliotrope rash and Gottron's sign appeared with elevated levels of serum aldolase.

View Article and Find Full Text PDF

A 59-year-old man with swollen submandibular glands developed an aortic aneurysm requiring aortic prosthesis implantation. Echocardiography performed to evaluate the cardiac function before the surgery incidentally revealed masses around the coronary arteries. The serum IgG4 levels were increased.

View Article and Find Full Text PDF

A 35-year-old woman was admitted to a hospital because of fever, sore throat, cervical lymph node swelling, and skin rashes. Laboratory data revealed leukocytosis and elevated C-reactive protein (CRP), aspartate aminotransferase, alanine aminotransferase, and ferritin levels. No antinuclear antibody or rheumatoid factor was found.

View Article and Find Full Text PDF

Objective: To investigate the safety and efficacy of a dose-escalation regimen of trimethoprim-sulfamethoxazole (TMP/SMX) for prophylaxis against Pneumocystis jiroveci pneumonia (PCP) in rheumatic diseases.

Methods: Data from 41 patients, who received glucocorticoids with or without immunosuppressive agents and prophylactic use of TMP/SMX, were retrospectively analyzed. Thirteen patients were started on a daily dose of 10% of single-strength (SS) TMP/SMX, which was increased gradually (dose-escalation group), while 28 patients were started on 1 SS tablet daily (routine group).

View Article and Find Full Text PDF