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101.
Steroidal saponin DT-13 (25 (R, S)-ruscogenin-1-O-[β-d-glucopyranosyl - (1 → 2)] [β-d-xylopyranosyl-(1 → 3)]-β-d-fucopyranoside) is the main active component of the tube of Liriope muscari (Decne.) Baily and has been studied as a candidate drug for cancer metastasis. The objective of this study was to evaluate the safety of DT-13 systematically by genotoxicity and acute oral toxicity and subchronic 90-day oral gavage toxicity. Results of Ames test confirmed that DT-13 did not induce mutations in histidine auxotrophs Salmonella typhimurium (TA 97, TA 98, TA 100 and TA 102) both in the presence and absence of metabolic activation system at the doses of 0.05-500 μg/plate. Meanwhile, DT-13 did not induce clastogenicity at doses of 1250, 2500 and 5000 mg/kg in mouse micronucleus test. And the single oral dose of DT-13 at 5000 mg/kg did not produce mortality or significant changes in the general behavior and gross appearance of the internal organs of mice. In subchronic toxicity study, DT-13 was administrated to Sprague-Dawley rats via oral gavage at doses of 10, 60 and 360 mg/kg for 90 days. Necropsy, hematological and biochemical analysis, and histopathological examination did not reveal any remarkable and treatment related changes. In conclusion, DT-13 is of low toxicity at the tested doses. 相似文献
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BACKGROUND: Serum specific IgE, basophil histamine release, and blood eosinophil parameters are associated with allergic rhinitis, but investigations of the relationship to the severity of allergic symptoms are few and conflicting. Our study aimed to investigate the seasonal changes in the following laboratory tests: specific IgE, basophil histamine release, eosinophil counts, and serum and plasma eosinophil cationic protein (ECP) and eosinophil protein X (EPX), and to analyze, in detail, the relationship of each individual test to the severity of symptoms in rhinitis patients allergic to both birch and grass pollen. METHODS: The above tests were performed on blood samples obtained from 49 allergic rhinitis patients during the birch-pollen season, during the grass-pollen season, and after the seasons. Symptom-medication diaries were filled in during both pollen seasons. We used partial least square (PLS) analysis to establish an optimal statistical link between the symptom score and medication and the laboratory tests, in an investigator-independent way. RESULTS: Increases in specific IgE, basophil histamine release, eosinophil counts, serum ECP and EPX, and plasma EPX were observed from the birch-pollen season to the grass-pollen season, followed by a decrease from the grass-pollen season to after the pollen seasons, except for the specific IgE. No seasonal changes in plasma ECP and total IgE were seen. The PLS analysis found a relationship between symptom score and medication and the aggregate laboratory tests (F-test value 40.2, correlation 0.34 for the cumulative relation). However, the variation in laboratory tests could explain only half of the total variation in symptoms and less than a quarter of the total variation in medication. The symptom score and, to a minor degree, medication were especially correlated with the basophil histamine-release results, with a decreasing relevance of specific IgE, eosinophil counts, total IgE, serum and plasma EPX, and serum ECP. Plasma ECP was not related to the symptom score and medication. CONCLUSIONS: A significant relationship between the severity of allergic rhinitis and various allergic inflammatory markers was found but could account for only a minor part of the variation in the patients' evaluation of their disease. 相似文献
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目的 分析Sysmex XS- 1000i血液分析仪计数嗜碱性粒细胞部分标本出现假性增高的影响原因.方法 对50例外周血中性粒细胞形态正常的标本使用Sysmex XE-5000、XS-1000i血液分析仪进行嗜碱性粒细胞计数,作相关统计学分析.4例使用Sysmex XS- 1000i血液分析仪计数嗜碱性粒细胞出现明显增高标本与手工计数法进行比较,做相关形态学分析.结果 50例外周血中性粒细胞形态正常的标本使用Sysmex XE-5000、XS-1000i血液分析仪进行嗜碱性粒细胞计数,两者相关系数r=0.715,嗜碱性粒细胞计数差异具统计学意义(P<0.01).4例使用Sysmex XS-1000i血液分析仪计数嗜碱性粒细胞出现明显增高标本均出现中性粒细胞中毒颗粒、退行性变等形态学改变.结论 两仪器间计数嗜碱性粒细胞结果差异有统计学意义,外周血中性粒细胞中毒颗粒等形态改变会造成XS-1000i血液分析仪计数嗜碱性粒细胞假性增高,对嗜碱性粒细胞异常增高的结果需进行手工计数分类. 相似文献
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G. E. Çelik J. T. Schroeder R. G. Hamilton S. S. Saini N. F. Adkinson 《Clinical and experimental allergy》2009,39(10):1522-1531
Background Basophil activation has been implicated in the pathogenesis of aspirin-exacerbated respiratory disease (AERD). However, a comprehensive analysis of basophil responses to aspirin in terms of mediator release, cytokine secretion and increased expression of surface activation markers has not been performed.
Objective To study the in vitro effects of aspirin on the concurrent release of histamine, leukotriene C4 (LTC4 ) and IL-4 from human basophils and to also evaluate changes in surface activation markers (CD63, CD69 and CD203c) expressed by these cells.
Methods Basophil-enriched cell suspensions from 10 patients with AERD and 10 healthy volunteers were incubated with lysine-aspirin for up to 3 h. Cells were analysed for expression of CD63, CD69 and CD203c using flow cytometry. Cell-free supernatants were evaluated for histamine, and LTC4 release and for IL-4 secretion.
Results Aspirin-induced expression of CD63, CD69 and CD203c yielded 30%, 80% and 70% sensitivity, respectively, but with poor specificity. There was no significant difference in LTC4 synthesis between groups. None of the patients with AERD (or controls) released IL-4 in response to aspirin. A higher dose of 5 mg/mL aspirin-mediated non-specific effects on basophils.
Conclusion Basophil responses to in vitro aspirin challenge are poor indicators of clinical sensitivity. Aspirin activates some basophils by means of mechanisms that differ from the classical IgE-mediated pathway. Our study also shows that the use of 27 m m of aspirin (5 mg/mL) by previous investigators causes non-specific basophil activation, thereby eliminating its usefulness in a cell-based diagnostic test for AERD. Evaluation of in vitro basophil activation has low clinical value in identifying aspirin-induced respiratory reactions. 相似文献
Objective To study the in vitro effects of aspirin on the concurrent release of histamine, leukotriene C
Methods Basophil-enriched cell suspensions from 10 patients with AERD and 10 healthy volunteers were incubated with lysine-aspirin for up to 3 h. Cells were analysed for expression of CD63, CD69 and CD203c using flow cytometry. Cell-free supernatants were evaluated for histamine, and LTC
Results Aspirin-induced expression of CD63, CD69 and CD203c yielded 30%, 80% and 70% sensitivity, respectively, but with poor specificity. There was no significant difference in LTC
Conclusion Basophil responses to in vitro aspirin challenge are poor indicators of clinical sensitivity. Aspirin activates some basophils by means of mechanisms that differ from the classical IgE-mediated pathway. Our study also shows that the use of 27 m m of aspirin (5 mg/mL) by previous investigators causes non-specific basophil activation, thereby eliminating its usefulness in a cell-based diagnostic test for AERD. Evaluation of in vitro basophil activation has low clinical value in identifying aspirin-induced respiratory reactions. 相似文献
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Background Basophils are increasingly recognized as playing important roles in the immune responses of allergic diseases and helminth infections. One of the main obstacles to studying basophils has been the lack of a simple and rapid assay to measure basophil activation in mice. Objective The purpose of this study was to develop an assay to measure murine basophil activation. Methods Mouse blood cells were stained with various combinations of positive and negative markers for basophils – sorted and then assessed for basophil purity by May‐Grünwald staining of cytospins. Once a flow cytometric strategy for staining basophils was determined, basophil surface expression of CD200R was assessed by multi‐colour flow cytometry after stimulation of whole blood with anti‐IgE, ionomycin or N‐formyl MetLeuPhe (fMLP). Confirmation of basophil activation was assessed by concomitant staining of cells for intracellular IL‐4. To test the ability of flow cytometric basophil CD200R measurements to assess for antigen‐specific IgE‐mediated activation of basophils, surface CD200R expression in response to in vitro stimulation with media alone, helminth antigen or ovalbumin was measured on basophils obtained from control mice, mice infected with helminths and mice sensitized to ovalbumin. Results Using anti‐IgE‐FITC as a positive marker and a combination of anti‐CD4‐PERCP and anti‐B220‐PERCP as negative markers resulted in a well‐separated basophil population. Additional staining with anti‐CD200R‐PE demonstrated that (1) basophil CD200R expression increases in response to anti‐IgE, ionomycin and fMLP, (2) most CD200R‐positive basophils also stain positively for IL‐4 and (3) CD200R expression increases after antigen‐specific activation of basophils in murine models of helminth disease and allergy. Conclusion We developed a multi‐colour flow cytometry assay that measures murine basophil activation by utilizing CD200R as an activation marker. This assay is straightforward and rapid, taking approximately half a day for obtaining blood, in vitro stimulation and flow cytometric analysis. 相似文献
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The clinical and immunological effects of Pru p 3 sublingual immunotherapy on peach and peanut allergy in patients with systemic reactions 下载免费PDF全文