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91.
Older Korean adults have lower physical function despite longer exercise times compared to their Japanese counterparts: A Japan‐Korea comparative study
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Tomohiro Kato Kazuhiko Yamamoto Hajime Takeuchi Mitsuo Okubo Eiji Hara Susumu Nakada Kinichiro Oda Koji Ito Kusuki Nishioka 《Arthritis \u0026amp; Rheumatology》1993,36(11):1580-1587
Objective. To investigate the distribution of B cell autoepitopes of human DNA topoisomerase I (topo I), an autoantigen associated with scleroderma. Methods. A complementary DNA clone, T1B, was used to produce recombinant proteins of topo I as β-galactosidase fusion proteins. Immunoreactivity to these fusion proteins was then tested in 35 anti–topo I–positive sera from patients with scleroderma, by immunoblotting, enzyme-linked immunosorbent assay, and double immunodiffusion. Results. One epitope was found to be universally recognized by all sera tested. Thirty-two of the samples recognized multiple antigenic regions, but sera from the remaining 3 patients recognized only this universal epitope, and in longitudinal studies of 1 of these 3 patients, the serum recognized only this epitope for more than 2 years, even though multiple, potent, antigenic regions were found on topo I. Conclusion. Recognition of multiple epitopes in most patients suggests that the topo I molecule itself would drive the autoimmunity on topo I. However, antigen-driven autoimmunity could not explain the production of the monoreactive anti–topo I antibody seen in the 3 patients. We thus hypothesize that there is a process whereby recognition of the universal epitope by cross-reaction develops into antigen-driven autoimmunity. 相似文献
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Yuki Sada Anand Chokkalingam Kenta Iyoki Masato Yoshioka Tomoya Ishikawa Yusuke Naraki Yutaka Yanaba Hiroki Yamada Koji Ohara Tsuneji Sano Tatsuya Okubo Zhendong Liu Toru Wakihara 《RSC advances》2021,11(37):23082
During AEI zeolite synthesis using acid treated FAU (AcT-FAU), we found the recrystallization of high-silica FAU with high crystallinity and Si/Al ratio of 6.1 using N,N-dimethyl-3,5-dimethylpiperidinium hydroxide (DMDMPOH) after 2 h, followed by the crystallization of AEI via FAU-to-AEI interzeolite conversion at a longer synthesis time. In order to understand the formation mechanism of high-silica FAU and generalize its direct synthesis, we have investigated this synthesis process. An analysis of the short-range structure of AcT-FAU revealed that it has an ordered aluminosilicate structure having a large fraction of 4-rings despite its low crystallinity. The changes in the composition of the products obtained at different synthesis times suggested that DMDMP+ plays a certain role in the stabilization of the FAU zeolite framework. Moreover, the results of thermogravimetric analysis showed that the thermal stability of DMDMP+ changed with the zeolite conversion. To the best of our knowledge, this is the first study to clarify the structure-directing effect of DMDMP+ on FAU zeolite formation.A high-silica FAU was obtained during FAU-to-AEI interzeolite conversion using acid treated FAU. 相似文献
97.
Differential diagnosis of pancreatic cancer and focal pancreatitis by using EUS-guided FNA 总被引:11,自引:0,他引:11
Takahashi K Yamao K Okubo K Sawaki A Mizuno N Ashida R Koshikawa T Ueyama Y Kasugai K Hase S Kakumu S 《Gastrointestinal endoscopy》2005,61(1):76-79
BACKGROUND: Despite advances in diagnostic imaging techniques, the differentiation between pancreatic cancer and focal pancreatitis remains difficult. This study evaluated the effectiveness of EUS-guided FNA in the differential diagnosis between pancreatic cancer and focal pancreatitis, with particular reference to detection of the K-ras point mutation. METHODS: The study included 62 consecutive patients with pancreatic ductal cancer and 15 patients with focal pancreatitis demonstrated as a pancreatic mass lesion by EUS. RESULTS: Sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of cytopathologic diagnosis were 82%, 100%, 86%, 100%, and 58%, respectively. Sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of histopathologic diagnosis were 44%, 100%, 55%, 100%, and 32%, respectively. The K-ras point mutation was found in 74% of pancreatic cancers and 0% of focal pancreatitis lesions. No complication of EUS-guided FNA was observed. CONCLUSIONS: EUS-guided FNA is useful for the differential diagnosis of pancreatic mass lesions caused by pancreatic cancer and focal pancreatitis. Analysis for the K-ras point mutation in specimens obtained by EUS-guided FNA may enhance diagnostic accuracy in indeterminate cases. 相似文献
98.
Hideo Okubo Hiromi Ishibashi Katsunori Shibata Kazunori Tsuda-Kawamura Toshiyuki Yanase 《Inflammation》1984,8(2):171-179
Distribution of uptake and catabolism of intravenously administered125l-labeled rat 2-macroglobulin(125I-2MG) were examined in normal, inflammatory, and tumor tissues of rats. Clearance of intravenously administered [125l]2MG from the circulation was rapid. Accumulation of this compound into inflammatory tissue was 2–3 times more extensive than in normal tissues. The accumulation into sarcoma tissue was much less. Radioactivity in TCA-PTA precipitates remained fairly constant for the first 12 h in inflammatory tissue and for the first 24 h in sarcoma. These patterns of accumulation were never observed in the normal tissues. As the kidney preferentially accumulated large amounts of [125l]2MG in the nondegraded form and its degradation products, the tissue may play a special role in the metabolism of 2MG. Rapid clearance from the circulation and relatively small amounts of accumulation in tissues suggest that 2MG may function as a protease inhibitor, mainly in the circulation rather than in the tissues. 相似文献
99.
Arisawa T Tahara T Shibata T Nagasaka M Nakamura M Kamiya Y Fujita H Nakamura M Yoshioka D Arima Y Okubo M Hirata I Nakano H 《International journal of molecular medicine》2007,20(4):539-544
Macrophage migration inhibitory factor (MIF) is a key proinflammatory mediator, which plays a pivotal role in inflammatory and immune diseases. We attempted to clarify associations of the functional polymorphisms of the MIF gene promoter with the development of chronic gastritis. The study was performed with 290 stocked DNAs from subjects with no evidence of gastric malignancy. We employed the PCR-SSCP method to detect gene polymorphisms. The severity of histological chronic gastritis in antral biopsy specimens was classified according to the updated Sydney system. Both the 7/7-CATT repeat at position -794 and the -173 C/C genotypes were significantly associated with a risk of developing severe gastric mucosal atrophy (OR, 9.69; 95% CI, 1.29-72.5; and OR, 4.60; 95% CI, 1.05-20.2, respectively). In subjects younger than 60 years old, the number of 7-CATT alleles was significantly correlated with both the activity and inflammation scores (p=0.0079 and 0.0080, respectively). Our results suggested that functional promoter polymorphisms of the MIF gene might be associated with the severity of gastric mucosal inflammation in younger subjects and with the subsequent development of mucosal atrophy. 相似文献
100.
Miu Okubo Risako Chiba Takeo Karakida Hajime Yamazaki Ryuji Yamamoto Saeko Kobayashi Takahiko Niwa Henry C. Margolis Takatoshi Nagano Yasuo Yamakoshi Kazuhiro Gomi 《Journal of oral biosciences / JAOB, Japanese Association for Oral Biology》2019,61(1):43-54