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OBJECTIVE: Definitive hematopoiesis starts in the aorta-gonad-mesonephros (AGM) region during mouse development and remarkably expands in the liver at a later stage of ontogeny. gp130 is a signal transducing receptor component shared by all the IL-6 family cytokines, whose gene ablation in mouse results in the significant reduction in the fetal liver hematopoiesis. The present study aims to evaluate the role of gp130 signaling in the fetal mouse AGM hematopoiesis. METHODS AND MATERIALS: Mouse AGM regions from the wild-type and gp130-deficient mice on embryonic day 11.5 were dissociated and cultured with a mixture of cytokines, including one which activates gp130. Wild-type human gp130 and its mutant constructs were introduced into cultured gp130-deficient AGM cells using retrovirus system. To further analyze gp130 downstream signaling, a dominant-negative mutant of STAT3 was also introduced. RESULTS: The gp130 deficiency in the culture of fetal mouse AGM cells resulted in the failure of the expansion of the c-kit(+), Sca-1(+), and lineage markers(-) population. Such failure was rescued by introduction of a wild-type gp130 expression construct but not its mutant constructs having no ability to activate STAT3. In the normal AGM cell culture, introduction of a dominant-negative form of STAT3 in which Y(705) was changed to phenylalanine suppressed the expansion of hematopoietic cell colonies. CONCLUSION: gp130 plays an indispensable role in the expansion of hematopoietic precursor cells in the fetal mouse AGM. In particular, the activation of STAT3 by gp130 is found to be important in this process.  相似文献   
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Rationale:Anti-myelin oligodendrocyte protein antibody-associated disease (MOGAD) is a new disease entity with various clinical phenotypes. MOGAD often present with recurrent optic neuritis (ON), and it can also develop as a compartment of neuromyelitis optica spectrum disorder (NMOSD). Moreover, multiple autoantibodies such as an anti-myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) had been reported in the serum of patients with NMOSD.Patient concerns:We report an 86-year-old woman with a 2-year history of microscopic polyangiitis (MPA). The patient had a rapid loss of vision in her left eye. No abnormal findings were observed on her left fundus, and she tested negative for MPO-ANCA upon admission. However, anti-MOG antibodies were observed in the patient''s serum and cerebrospinal fluid.Diagnosis:A diagnosis of MOGAD complicated with MPA was made.Interventions:The patient received twice steroid pulse therapy and oral azathioprine as maintenance therapy.Outcomes:Her vision rapidly recovered, and no subsequent relapse was observed during the 8-month observation period.Conclusion:To the best of our knowledge, this is the first case of MOGAD complicated with MPA, and steroid pulse therapy and azathioprine therapy were effective for ON caused by MOGAD.  相似文献   
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TAFRO syndrome is a systemic inflammatory, lymphoproliferative disorder, but the pathophysiology of the disease is unknown. It is typically characterized by thrombocytopenia, anasarca, a fever, reticulin fibrosis, renal dysfunction, and organomegaly. However, other manifestations have been also reported. We encountered a 43-year-old man with TAFRO syndrome who showed mediastinal panniculitis, liver damage, and adrenal lesions in addition to the core signs. He achieved complete remission with combination therapy of corticosteroids, tocilizumab, and cyclosporin, and remission was maintained even after drug discontinuation at 15 months. Atypical manifestations and complete remission of TAFRO syndrome were remarkable features of our case.  相似文献   
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BACKGROUND: Hypersensitivity reactions to fish are a common food allergy, but IgE-binding activity to fish species have not been fully elucidated. The aim of this study was to identify fish with high binding activity to IgE in sera from Japanese fish-hypersensitive individuals. METHODS: 38 children with a history of at least one episode of hypersensitivity after ingestion of fish were enrolled and 34 children with no history of reactions and negative IgE results for at least five kinds of fish antigen were included as controls. Using a radioallergosorbent test, we examined IgE-binding to each fish species using sera from fish-hypersensitive subjects. Fish were then graded according to IgE-binding activity. RESULTS: Many fish species, including red salmon, silver salmon, yellowfin tuna, big eyed tuna, Atlantic tuna, saurel, skipper, yellowtail, Japanese sardine, bonita and mackerel had high IgE-binding activity. All of these fish are abundantly consumed in Japan. The hypersensitivity reactions experienced by many subjects occurred after ingestion of species with high IgE-binding activity. Only halibut (Osteichthyes) and sharks (Chondrichthyes) had low IgE-binding activity. CONCLUSIONS: A correlation was observed between IgE levels and expression of symptoms after fish ingestion. High consumption of salmon, tuna, scad (including saurel), skipper, yellowtail, sardine, bonita and mackerel in Japan might be the cause of the high IgE-binding activity of these species. The grades of fish species consumed widely in Japan are likely to be useful for nutritional instruction of fish-allergic patients.  相似文献   
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Sessile serrated adenoma/polyps (SSA/Ps) of the colon are thought to be precursors of sporadic carcinomas. Although it is suggested that SSA/P may grow rapidly from the early stage, its cell kinetics remains obscure. To solve this problem, we analyzed the mitotic and apoptotic activity of normal crypts, microvesicular hyperplastic polyps (MVHPs), and tubular adenomas (TAs), using phospho-histone H3 and cleaved caspase 3 immunohistochemistry. The mitotic index for SSA/Ps (mean, 5.63) and TAs (6.98) was significantly higher than those for normal crypts (2.72) and MVHPs (2.86). Of all tested lesions, the apoptotic index was lowest for SSA/Ps (0.96; normal, 2.71; MVHPs, 2.62; TAs, 6.01) with statistically significant differences. The net growth ratio was close to 1.0 in normal crypts (1.07) while remaining low in MVHPs (1.06) and TAs (1.38), but was markedly elevated in SSA/Ps (7.32, P?<?0.01) due to the large imbalance between mitosis and apoptosis. As to apoptosis regulatory proteins, expression of anti-apoptotic Bcl-2 was significantly reduced or undetectable in MVHPs and SSA/Ps, while TAs showed stronger staining than normal crypts. Expression of pro-apoptotic Bax and its activators, Bim and Bad, was significantly reduced in MVHPs and SSA/Ps. We suggest that other complex mechanisms may act synergistically with Bax, Bim, or Bad deficiency to regulate apoptosis suppression in SSA/Ps.  相似文献   
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Background

It is widely recognized that overt hyper- as well as hypothyroidism are potential causes of heart failure (HF). Additionally it has been recently reported that subclinical hypothyroidism (sub-hypo) is associated with atherosclerosis, development of HF, and cardiovascular death. We aimed to clarify the effect of sub-hypo on prognosis of HF, and underlying hemodynamics and exercise capacity.

Methods

We measured the serum levels of thyroid stimulating hormone (TSH) and free thyroxine (FT4) in 1100 consecutive HF patients. We divided these patients into 5 groups on the basis of plasma levels of TSH and FT4, and focused on euthyroidism (0.4 ≤ TSH ≤ 4 μIU/mL and 0.7 ≤ FT4 ≤ 1.9 ng/dL; n = 911; 82.8%) and sub-hypo groups (TSH > 4 μIU/mL and 0.7 ≤ FT4 ≤ 1.9 ng/dL; n = 132; 12.0%). We compared parameters of echocardiography, cardiopulmonary exercise testing, and cardiac catheterization, and followed up for cardiac event rate and all-cause mortality between the 2 groups.

Results

Although left ventricular ejection fraction did not differ between the 2 groups, the sub-hypo group had lower peak breath-by-breath oxygen consumption and higher mean pulmonary arterial pressure than the euthyroidism group (peak breath-by-breath oxygen consumption, 14.0 vs 15.9 mL/min/kg; P = 0.012; mean pulmonary arterial pressure, 26.8 vs 23.5 mm Hg, P = 0.020). In Kaplan-Meier analysis (mean 1098 days), the cardiac event rate and all-cause mortality were significantly higher in the sub-hypo group than those in the euthyroidism group (log rank, P < 0.01, respectively). In Cox proportional hazard analysis, sub-hypo was a predictor of cardiac event rate and all-cause mortality in HF patients (P < 0.05, respectively).

Conclusions

Sub-hypo might be associated with adverse prognosis, accompanied by impaired exercise capacity and higher pulmonary arterial pressure, in HF patients.  相似文献   
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