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21.
D Singh M Corradi E Bindi R Baronio S Petruzzelli P Paggiaro 《Pulmonary pharmacology & therapeutics》2012,25(5):392-398
BackgroundShort-acting beta2-agonists like salbutamol and terbutaline are used as rescue medications for acute bronchoconstriction and relief of symptoms due to their rapid onset of action. The aim of this study was to assess whether inhaled beclomethasone dipropionate (BDP)/formoterol fumarate (FF) combination in extrafine formulation is non-inferior to salbutamol in the speed of reverting methacholine-induced bronchoconstriction and symptoms.MethodsFifty-six asthmatic patients were examined in a multicentre, randomised, double blind, double dummy, active treatment and placebo controlled three period cross-over study. On three different days, a single dose of BDP/FF 100/6 μg in pressurised metered-dose inhaler (pMDI) extrafine formulation or salbutamol 200 μg pMDI or placebo was inhaled after FEV1 had dropped by 30–45% with methacholine challenge.ResultsThe median time to recovery of FEV1 to 85% of baseline was similar for BDP/FF and salbutamol (3.66 and 2.15 min, respectively), but significantly longer for placebo (21.1 min). The planned analysis on adjusted mean time to recovery showed that the difference from methacholine-induced bronchoconstriction between BDP/FF and salbutamol was 3.82 min (95% confidence interval: ?0.85 to 8.5), therefore greater than 3 min supposed in the study design. The difference between BDP/FF and salbutamol was not clinically significant. The two active treatments were also comparable in terms of the relief of symptoms (as assessed by the Borg dyspnoea scale).ConclusionsBDP/FF combination has a fast onset of action, similar to that of salbutamol, and may represent a good alternative as rescue medication in asthmatic patients. 相似文献
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Human spleen cell generation of factors stimulating human pluripotent stem cell, erythroid, and myeloid progenitor cell growth 总被引:2,自引:0,他引:2
Mitogen-stimulated murine spleen cells produce humoral substances capable of supporting murine hematopoiesis and pluripotent stem cell proliferation in vitro. Thus, we evaluated conditioned media generated by human spleen cells (SCM) in the presence or absence of mitogens for factors stimulatory for human pluripotent (CFU-GEMM), erythroid (BFU- E), and myeloid (CFU-GM) precursors. Two and one half percent to 10% SCM stimulated proliferation of all three types of precursor cells from nonadherent buoyant human marrow target cells. Mitogen-stimulated SCM augmented CFU-GM (175% to 225%), whereas CFU-GEMM and BFU-E growth was essentially unchanged. Cell separation procedures used to determine which cells provided these microenvironmental stimuli indicated that nonadherent mononuclear spleen cells provided the bulk of the CSF-GM, whereas adherent cells (95% nonspecific esterase + monocyte- macrophages) and nonadherent cells provided similar proportions of CSF- mix and erythroid burst-promoting activity (BPA). The nonadherent cells generating high levels of CSF-mix, BPA, and CSF-GM were predominantly Leu-1-negative, ie, non-T, cells. In the presence or absence of mitogens, SCM was a more potent source (1.3- to 3.8-fold) than peripheral leukocyte CM of the growth factors for the three progenitor cell types. Specific in situ cytochemical stains for analyzing morphology of myeloid colonies demonstrated that SCM stimulated the proliferation of the same types and proportions of colonies as human placental CM, suggesting that these CMs may contain similar CSF-GMs. These data show the contribution of spleen cell subsets to the generation of hematopoietic growth factors and the responsiveness of these cells to various mitogenic stimuli. 相似文献
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Native associations of early hematopoietic stem cells and stromal cells isolated in bone marrow cell aggregates 总被引:4,自引:3,他引:4
In suspensions of murine bone marrow, many stromal cells are tightly entwined with hematopoietic cells. These cellular aggregations appear to exist normally within the marrow. Previous studies showed that lymphocytes and stem cells adhered to stromal cells via vascular cell adhesion molecule 1 (VCAM1). Injection of anti-VCAM1 antibody into mice disrupts the aggregates, showing the importance of VCAM1 in the adhesion between stromal cells and hematopoietic cells in vivo. Early hematopoietic stem cells were shown to be enriched in aggregates by using a limiting-dilution culture assay. Myeloid progenitors responsive to WEHI-3CM in combination with stem cell factor (c-kit ligand) and B220- B-cell progenitors responsive to insulin-like growth factor-1 in combination with interleukin-7 are not enriched. We propose a scheme of stromal cell-hematopoietic cell interactions based on the cell types selectively retained within the aggregates. The existence of these aggregates as native elements of bone marrow organization presents a novel means to study in vivo stem cell-stromal cell interaction. 相似文献
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Follow-up study of 232 patients with occupational asthma caused by western red cedar (Thuja plicata) 总被引:10,自引:0,他引:10
M Chan-Yeung L MacLean P L Paggiaro 《The Journal of allergy and clinical immunology》1987,79(5):792-796
A total of 232 patients with red cedar asthma diagnosed by inhalation provocation tests were observed an average of 4 years after the initial diagnosis. The status during the follow-up examination was as follows: 96 patients continued to work with red cedar, and 136 left the industry and had no further exposure to red cedar in their jobs or hobbies. Of the 136 patients who left the industry, only 55 (40.4%) recovered completely, whereas the remaining 81 (59.6%) continued to experience attacks of asthma of varying severity. The initial pulmonary function tests were significantly higher among the asymptomatic group compared to the symptomatic group (FEV1 99.3 +/- 2.7% versus 90.5 +/- 2.2% predicted, respectively). Methacholine PC20 during the initial examination was higher among the asymptomatic group than in the symptomatic group (1.46 +/- 3.96 mg/ml versus 0.77 +/- 4.52 mg/ml, respectively). These findings indicate that the patients in the asymptomatic group were diagnosed at an earlier stage of the disease. This observation was confirmed by the significantly shorter duration of symptoms before diagnosis among the asymptomatic patients compared to the symptomatic patients (1.6 +/- 1.9 versus 2.6 +/- 4.3 years). Race, smoking status, immediate skin reactivity, and presence of plicatic acid-specific IgE antibodies did not influence the outcome of these patients. Of the 96 patients who continued to work with red cedar, 47 were exposed daily, whereas 41 were exposed intermittently.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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M ODowd T Geoghegan PL Munk G McAuley WC Torreggiani 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):386-388
Osseous haemophilic pseudotumours are uncommon. The commonest sites of involvement are the femur and the pelvis. Trauma is the initiating factor in most reported cases and repeated bleeding into the lesion contributes to their growth. Most lesions grow slowly and are often asymptomatic. Complications include massive haemorrhage, infection and pathological fracture. We present an extremely unusual presentation where a large haemophilic pseudotumour of the pelvis extended to impinge the adjacent colon, resulting in large bowel obstruction. 相似文献