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Featured researches published by Ryusaku Nagayoshi.


Biochemical and Biophysical Research Communications | 2002

Nitration and chlorination of folic acid by peroxynitrite and hypochlorous acid, and the selective binding of 10-nitro-folate to folate receptor β

Motoyuki Nakamura; Ryusaku Nagayoshi; Kosei Ijiri; Noriko Nakashima-Matsushita; Toru Takeuchi; Takami Matsuyama

The aim of this work was to characterize folates modified by ONOO(-) and HOCl and to evaluate the binding capacity of folates modified by ONOO(-) to folate receptor alpha and beta. For the modification of folate by ONOO(-), folic acid was reacted with the combination of PMA activated PMN and PAPA NONOate or chemically synthesized ONOO(-). For the modification of folate by HOCl, folic acid was reacted with the combination of MPO and H(2)O(2) or NaOCl. The structures of products were determined by 1H-NMR and MALDI-TOF mass. Nitrated folate species were identified as 10-nitro-folate and 12-nitro-folate, and chlorinated folate was identified as 12-chloro-folate. The 10-nitro-folate showed the selective binding to FR-beta, compared to folic acid.


Spine | 2009

Evaluation of occipitocervical subluxation in rheumatoid arthritis patients, using coronal-view reconstructive computed tomography.

Ryusaku Nagayoshi; Kosei Ijiri; Tsuyoshi Takenouchi; Eiji Taketomi; Harutoshi Sakakima; Setsuro Komiya

Study Design. Reconstructive computed tomography (CT) study of occipito-atlanto and atlantoaxial joints in RA patients. Summary of Background Data. The occipitocervical region is one of the most common sites of rheumatoid arthritis (RA). Although lateral radiography has been used for the diagnosis of atlantoaxial subluxation and vertical subluxation, reconstructive CT imaging of the occipito-atlanto and atlantoaxial joints is more sensitive in detecting morphologic changes in this region. We investigated this region in RA patients, using coronal-view reconstructive CT images, and examined the relationship between the morphology and other radiographic parameters. Methods. The occipitocervical region was examined in 58 female RA patients by reconstructive CT, plain radiography, and MRI. The degree of destructive change on reconstructive CT was compared to that on other radiographic evaluations. Results. Coronal-view reconstructive CT revealed primary destructive changes before detection by lateral radiography, using Redlund-Johnell or Ranawat values. A Redlund-Johnell value less than 34 mm was diagnostic for occipitocervical subluxation in female RA patients. Conclusion. Coronal-view reconstructive CT is useful for the diagnosis of occipitocervical joint subluxation in RA.


Neurosurgery | 2010

Magnetic resonance angiography for vertebral artery evaluation in rheumatoid arthritis patients.

Michihisa Zenmyo; Kosei Ijiri; Hiromi Sasaki; Harutoshi Sakakima; Eiji Taketomi; Ryusaku Nagayoshi; Takuya Yamamoto; Setsuro Komiya

OBJECTIVETo examine the radiological features of vertebral artery (VA) displacement/occlusion associated with rheumatoid arthritis (RA) spine using magnetic resonance angiography. METHODSForty-seven RA patients with upper cervical lesions were evaluated for patency or abnormality of the VA by extracranial magnetic resonance angiography, with comparison of findings with those of 46 healthy volunteers. RESULTSVA occlusion occurred in 4 patients (8.5%) and VA stenosis in 9 patients (19.1%). Anomaly of the VA was also observed in 3 patients (6.4%). No occlusion or anomaly was found in healthy volunteers, but 1 case of stenosis was found. Severity of vertical subluxation was correlated with the presence of VA abnormality in RA patients. CONCLUSIONThe incidence of VA abnormality was 34% in RA patients and 2% in healthy volunteers. Magnetic resonance angiography is useful for screening for abnormality of the entire VA.


International Journal of Neuroscience | 2010

Intradural Neurenteric Cyst—Two Case Reports of Surgical Treatment

Michihisa Zenmyo; Yasuhiro Ishido; Takuya Yamamoto; Ichiro Kawakura; Ryusaku Nagayoshi; Kazunori Yone; Setsuro Komiya; Kosei Ijiri

ABSTRACT Intradural neurenteric cysts are rare congenital lesions and arise from incomplete separation of the developing notochord and foregut in the embryo. Neurenteric cysts are often seen in conjunction with other forms of occult spinal dysraphism. The cases of a 48-year-old male with pain in the right shoulder and numbness in both hands and a 7-year-old girl with subacute muscle weakness of the lower extremities are presented. Both patients underwent surgery. One lesion was completely excised, while the other could be only partially removed because of negative monitoring potential during the operation. Histological examination, showing pseudostratified ciliated columnar epithelium, confirmed the diagnosis of neurenteric cyst. The symptoms in both patients nearly disappeared after surgery. Recurrence of cyst was observed in the girl, though without neurological symptoms. In conclusion, two cases of intradural extramedullary cysts are reported. Clinical presentations, intraoperative findings, and histological features are discussed with a review of the literature.


Journal of orthopaedic surgery | 2013

Paget disease of bone in Japanese patients: a report of three cases

Satoshi Nagano; Masahiro Yokouchi; Ryusaku Nagayoshi; Hiromi Sasaki; Hirofumi Shimada; Takao Setoguchi; Kosei Ijiri; Setsuro Komiya

Paget disease of bone (PDB) is a bone metabolic disorder causing pain, fractures, and deformity. Its incidence is estimated to be 1 to 2% in Caucasians older than 55 years, but in Asian populations the incidence is rare. We report on 2 female and one male Japanese patients aged 46 to 73 years with PDB. One patient had monostotic disease with pain around the shoulder and the other 2 were asymptomatic. All patients had elevated alkaline phosphatase (ALP) levels (range, 629–957 U/L). Two patients responded to oral bisphosphonate treatment and achieved normalised ALP levels and pain relief. One patient with polyostotic disease did not show any change in ALP levels. The diagnosis of the disease and the indications for bisphosphonate treatment are discussed.


Arthritis & Rheumatism | 2005

Effectiveness of anti–folate receptor β antibody conjugated with truncated Pseudomonas exotoxin in the targeting of rheumatoid arthritis synovial macrophages

Ryusaku Nagayoshi; Taku Nagai; Kakushi Matsushita; Katsuaki Sato; Nobuhiko Sunahara; Takemasa Matsuda; Tadashi Nakamura; Setsuro Komiya; Masanori Onda; Takami Matsuyama


The Journal of Rheumatology | 2002

Differential expression patterns of secreted frizzled related protein genes in synovial cells from patients with arthritis

Kosei Ijiri; Ryusaku Nagayoshi; Noriko Matsushita; Hiromichi Tsuruga; Noboru Taniguchi; Akira Gushi; Harutoshi Sakakima; Setsuro Komiya; Takami Matsuyama


Archive | 2005

Therapeutic Medicine Containing Monoclonal Antibody Against Folate Receptor Beta (Fr-Beta)

Takami Matsuyama; Ryusaku Nagayoshi; Yasuhiro Tsuneyoshi; Taku Nagai; Kakushima Matsushita


Orthopaedics and Traumatology | 2010

Problems and Clinical Course after Operation of Spinal Cord Tumor at Upper Cervical Spine

Ichiro Kawamura; Kosei Ijiri; Takuya Yamamoto; Michihisa Zenmyo; Ryusaku Nagayoshi; Mikio Terahara; Hikaru Sakamoto; Tomoka Sanno; Kazunori Yone; Setsuro Komiya


Orthopaedics and Traumatology | 2010

Surgical Results of Cervical Radiculopathy: Anterior Cervical Discectomy and Fusion versus Posterior Microendoscopic Foraminotomy

Fumito Tanabe; Eiji Taketomi; Kosei Ijiri; Takuya Yamamoto; Ryusaku Nagayoshi; Fumihiro Miyaguchi; Hiroyuki Tominaga; Yoshimi Maeda; Yasuhiro Ishido; Kazunori Yone; Setsuro Komiya

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