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Sada K  Miah SM  Maeno K  Kyo S  Qu X  Yamamura H 《Blood》2002,100(6):2138-2144
Aggregation of high-affinity IgE receptor FcepsilonRI induces sequential activation of nonreceptor-type protein-tyrosine kinases and subsequent tyrosine phosphorylation of cellular proteins, leading to degranulation in mast cells. A hematopoietic cell-specific adaptor protein, 3BP2, that was originally identified as an Abl SH3-binding protein was rapidly tyrosine phosphorylated by the aggregation of FcepsilonRI on rat basophilic leukemia RBL-2H3 cells. Tyrosine phosphorylation of 3BP2 did not depend on calcium influx from external sources. To examine the role of 3BP2 in mast cells, we overexpressed the SH2 domain of 3BP2 in the RBL-2H3 cells. Overexpression of 3BP2-SH2 domain resulted in a suppression of antigen-induced degranulation as assessed by beta-hexosaminidase release. Even though overall tyrosine phosphorylation of cellular protein was not altered, antigen-mediated tyrosine phosphorylation of phospholipase C-gamma (PLC-gamma) and calcium mobilization were significantly suppressed in the cells overexpressing the 3BP2-SH2 domain. Furthermore, antigen stimulation induced the association of 3BP2-SH2 domain with LAT and other signaling molecule complexes in the RBL-2H3 cells. FcepsilonRI-mediated phosphorylation of JNK and ERK was not affected by the overexpression of 3BP2-SH2 domain. These data indicate that 3BP2 functions to positively regulate the FcepsilonRI-mediated tyrosine phosphorylation of PLC-gamma and thereby the signals leading to degranulation.  相似文献   
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We report a 27-year-old case of juvenile idiopathic arthritis (JIA) having been stopped infliximab during pregnancy. She was safely treated by infliximab therapy with premedications for preventing infusin reactions after her delivery, and then improved in the same manner as when she had been treated with infliximab therapy before pregnancy. As a result, it remains unclear whether or not we can use infliximab to control disease activities during pregnancy. In addition, it is also important to clarify whether or not premedications should be used when resuming infliximab treatment in such patients after pregnancy. These problems still remain controversial. More definitive data are needed in order to allow rheumatologists to better select the optimal TNF-alpha inhibitor therapy when treating pregnant JIA patients.  相似文献   
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A low pressure sealed-air hot tube gas forming process of ultra-high strength steel tubes was developed not only to change the cross-section of the hollow products by bulging but also to increase the strength of components. Gas-formed components are typically formed by a controlled-gas pressure with extremely high internal pressure, which leads to affected production costs and safety. Moreover, compressing the gas with high pressure requires high energy during its preparation. Therefore, to simplify the internal pressure controlling system and improve the safety factor in gas forming processes, the sealed-air tubes are formed with a quite low initial pressure. The pressure of the sealed air increased with increasing temperature of the air inside the resistance-heated tube, and the bulging deformation was controlled only by axial feeding. The effects of the initial pressure and heating temperature on the bulging deformation and quenchability of the tubes, and the effect of the starting time of axial feeding on the bulging behavior were examined. Consequently, ultra-high strength steel bulged parts were produced even in low initial internal pressure and with the rapid heating of the tubes.  相似文献   
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Aims/IntroductionThis study aimed to reveal lifestyle changes and their impact on glycemic control and weight control in patients with diabetes during the coronavirus disease 2019 (COVID‐19) pandemic in Japan.Materials and MethodsWe retrospectively analyzed 1,402 outpatients with diabetes at a clinic in Osaka, Japan, who responded to an interview sheet regarding lifestyle changes during the COVID‐19 pandemic between 28 March and 30 May 2020. The association of lifestyle changes with hemoglobin A1c (HbA1c) and weight changes from February to May 2020 was investigated using the linear regression model. We also investigated the association with clinically important change of HbA1c (by ≥0.3%) and bodyweight (by ≥3%), using the cumulative link model.ResultsLeisure time and other outside physical activities were decreased in one‐quarter of patients during the COVID‐19 pandemic, whereas the amount of meals and snacks was decreased and increased in approximately 10%, respectively. The change in leisure time physical activities was inversely associated with HbA1c and weight changes, whereas the quantitative change of meals with the decline in eating out and that of snacks were positively associated with HbA1c and weight changes (all P < 0.05). The quantitative change of meals without the decline in eating out was also positively associated with weight change (P = 0.012). The cumulative link model for clinically important HbA1c and weight change showed broadly similar associations, except for that between snacks and bodyweight (P = 0.15).ConclusionsA considerable number of outpatients with diabetes experienced lifestyle changes during the COVID‐19 pandemic. The lifestyle changes were associated with HbA1c and weight changes.  相似文献   
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Summary Large plaque (G) and small plaque (8) variants were cloned from stock culture of Sindbis virus. Addition of protamine to agar overlay was shown to have little or no effect on the size of plaques produced by G variant, whereas S virus plaque size was significantly increased. This finding suggests that the S variant is more susceptible than the G variant to the inhibitory action of agar factor. The G and S variants differed markedly in their sensitivity to the antiviral action of interferon. Evidence was obtained that the S variant is more susceptible to the action of interferon. The difference of G and S variants in susceptibility to the action of interferon and agar factor may account for the difference of their plaque size. Growth and cytopathic effect of the S variant in a HVJ carrier HeLa cell culture (HeLaHVJ) was greatly enhanced in contrast to those in normal HeLa cells. Enhancement of growth of wild-type virus in HeLaHVJ cells was not so significant as in the case of the S variant. These observations were discussed in relations to the properties of the S variant and the cells of HeLaHVJ.Dedicated to ProfessorJohn F. Enders on the occasion of his 70th birthday.  相似文献   
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OBJECTIVE: To investigate the prevalence of cumulative organ damage in patients with juvenile-onset systemic lupus erythematosus (SLE) and its association with demographic and clinical variables, medication use, and quality of life. METHODS: The occurrence of organ system damage, as measured by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI), was determined for 387 patients consecutively enrolled in pediatric rheumatology centers from Europe, the US, Mexico, and Japan. Risk factors for damage included demographic variables; clinical manifestations at diagnosis; previous corticosteroid, immunosuppressive, and antimalarial therapies; disease activity; and quality of life. RESULTS: Overall, 195 (50.5%) patients had damage within a mean of 5.7 years after disease onset. Renal (21.8%) and neuropsychiatric (15.8%) system involvement were observed most frequently, followed by musculoskeletal (11.7%), ocular (10.9%) and skin (9.6%) system involvement, with a mean SDI score of 1.1. In multivariate models, the occurrence of neuropsychiatric manifestations at diagnosis, a longer disease duration, and a greater number of intravenous cyclophosphamide pulses showed the strongest association with the presence of damage. CONCLUSION: We found evidence of cumulative organ damage, as measured by the SDI, in half of the patients with juvenile-onset SLE. Damage was significantly more likely in patients who had experienced neuropsychiatric manifestations at diagnosis, had a longer disease duration, and had received more intravenous pulses of cyclophosphamide.  相似文献   
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