Ryoji Yanai, Hei Sho Uchi, Yukiko Kondo, Youichiro Fujitsu, Katsuyoshi Suzuki, Keiko Yoshimura, Naoki Kumagai, Mariko Egawa and Yoshinori Mitamura : The epidemiology of uveitis: comparison of its causes and visual outcomes between three-tiered medical facilities in Ube city, Scientific Reports, 15, 1, 8998, 2025.
(Summary)
This study aimed to conduct a comparative epidemiological survey of uveitis across various healthcare settings and elucidate the clinical characteristics. We conducted a retrospective cross-sectional study in the Ube-City medical region in Yamaguchi prefecture and recruited 268 patients from a university hospital (151 patients), municipal hospitals (51 patients), and private eye clinics (58 patients). Medical records of patients newly diagnosed with uveitis between January 2018 and December 2019 in the institutes were included, reviewed, and compared. The main outcomes included the number of uveitis causes, treatment methods, and visual acuity. Panuveitis, which is associated with systemic diseases, such as Vogt-Koyanagi-Harada disease and sarcoidosis, was more prominent in university hospital patients. Conversely, anterior uveitis, including traumatic iritis, was prominently detected in general hospitals and private eye clinics. The best-corrected visual acuity improved to 1.0 (logMAR = 0); an improvement of 74%, 61%, and 54% was observed in private eye clinic, general hospital, and university hospital patients, respectively. This study identified differences in uveitis presentation and treatment across diverse clinical settings. The results of this study provide valuable data for differentiating the causes of uveitis at university hospitals, general hospitals, and private eye clinics.
(Keyword)
Community hospitals / Panuveitis / University hospital / Uveitis / Visual impairment
Ryoji Yanai, Sora Mizukami, Akihiko Sakamoto, Kenji Takemoto, Tetsuya Seto, Kazuya Uehara, Kiminori Yukata, Takashi Sakai, Keiko Iwaisako, Norihiko Takeda, Ryoji Yanai and Masataka Asagiri : Cell cycle checkpoint factor p15Ink4b is a novel regulator of osteoclast differentiation., Scientific Reports, 15, 1, 2025.
(Summary)
Osteoclasts are specialized cells essential for bone resorption, a crucial process in bone remodeling, and dysregulation of osteoclastogenesis can lead to pathological bone loss such as osteoporosis and rheumatoid arthritis. Therefore, understanding the precise mechanisms governing osteoclast differentiation is crucial for developing effective therapies for skeletal diseases. In osteoclastogenesis, as well as other differentiated cells, it is well understood that cell cycle arrest is essential for terminal differentiation and is tightly regulated by CDK inhibitors such as Cip/Kip family and Ink4 family protein. In this manuscript, we identified p15Ink4b, a member of the Ink4 family, as a novel regulator of osteoclastogenesis by comprehensive single-cell RNA sequence data reanalyzing. Furthermore, histological analysis and in vitro osteoclast differentiation assay revealed that p15Ink4b functionally regulates osteoclastogenesis. Our findings may not only provide insights into the molecular mechanisms of osteoclast differentiation but also underscore the potential of harnessing cell cycle mechanisms to develop novel therapeutic strategies for bone diseases.
Tetsuya Seto, Kiminori Yukata, Shunya Tsuji, Yusuke Takeshima, Takeshi Honda, Akihiko Sakamoto, Kenji Takemoto, Hiroki Sakai, Mayu Matsuo, Yurika Sasaki, Mizuki Kaneda, Mikako Yoshimura, Atsushi Mihara, Kazuya Uehara, Aira Matsugaki, Takayoshi Nakano, Koji Harada, Yoshiro Tahara, Keiko Iwaisako, Ryoji Yanai, Norihiko Takeda, Takashi Sakai and Masataka Asagiri : Methylglyoxal compromises callus mineralization and impairs fracture healing through suppression of osteoblast terminal differentiation., Biochemical and Biophysical Research Communications, 747, 2025.
(Summary)
Impaired fracture healing in diabetic patients leads to prolonged morbidity and increased healthcare costs. Methylglyoxal (MG), a reactive metabolite elevated in diabetes, is implicated in various complications, but its direct impact on bone healing remains unclear. Here, using a non-diabetic murine tibial fracture model, we demonstrate that MG directly impairs fracture healing. Micro-computed tomography revealed decreased volumetric bone mineral density in the callus, while callus volume remained unchanged, resulting in a brittle bone structure. This was accompanied by reduced expression of osteocalcin and bone sialoprotein, both critical for mineralization. Biomechanical analysis indicated that MG reduced the mechanical resilience of the fracture site without altering its elastic strength, suggesting that the impairment was not primarily due to the accumulation of advanced glycation end-products in the bone extracellular matrix. In vitro studies confirmed that non-cytotoxic concentrations of MG inhibited osteoblast maturation and mineralization. Transcriptomic analysis identified downregulation of Osterix, a key transcription factor for osteoblast maturation, without altering Runx2 levels, leading to decreased expression of key mineralization-related factors like osteocalcin. These findings align with clinical observations of reduced circulating osteocalcin levels in diabetic patients, suggesting that the detrimental effects of MG on osteoblasts may extend beyond bone metabolism. Our study highlights MG and MG-sensitive pathways as potential therapeutic targets for improving bone repair in individuals with diabetes and other conditions characterized by elevated MG levels.
Ryoji Yanai and Yoshinori Mitamura : The influence of thick-type conventional soft contact lenses YOUSOFT ®, developing for the astigmatism correction on a rabbit corneal epithelium, ARVO2025, Apr. 2025.
2.
Ryoji Yanai, 三﨑 裕子, Mariko Egawa, Masayuki Yamada and Yoshinori Mitamura : Two cases of Tatto-associated granulomatous uveitis, INFLAMMATIO 2024, Nov. 2024.
3.
Ryoji Yanai and Yoshinori Mitamura : The effects of the thick type of YOUSOFT contact lenses for aphakic hyperopia on a rabbit corneal epithelium, ISCLR Symposium, Aug. 2024.
Ocular gateway reflex, which is mediated by sensory nerve, and relapsing control by neurotransmitter (Project/Area Number: 21K09743 )
Development of new treatment for age related macular degeneration focused on blood retinal barrier independent with VEGF (Project/Area Number: 18K09449 )
The involvement of potentially allergic inflammation to fibrosis in conjunctival tissue (Project/Area Number: 15K10870 )
Elucidation of a destruction mechanism and development of new treatment on intraocular chronic inflammatory diseases with CYP metabolites (Project/Area Number: 15K10869 )
Detectino of AGEs in the basement membrane in the eye, and establishment of the AGE detection clinical equipments. (Project/Area Number: 26670755 )
Retinal regeneration due to regulation of natural immunity (Project/Area Number: 26293373 )