Background:  Patients with severe persistent asthma who are inadequately controlled despite treatment according to current asthma management guidelines have a significant unmet medical need. Such patients are at high risk of serious exacerbations and asthma‐related mortality. Methods:  Here, we pooled data from seven studies to determine the effect of omalizumab, an anti‐immunoglobulin E (IgE) monoclonal antibody, on asthma exacerbations in patients with severe persistent asthma. Omalizumab was added to current asthma therapy and compared with placebo (in five double‐blind studies) or with current asthma therapy alone (in two open‐label studies). The studies included 4308 patients (2511 treated with omalizumab), 93% of whom had severe persistent asthma according to the Global Initiative for Asthma (GINA) 2002 classification. Using the Poisson regression model, results were calculated as the ratio of treatment effect (omalizumab : control) on the standardized exacerbation rate per year. Results:  Omalizumab significantly reduced the rate of asthma exacerbations by 38% (P < 0.0001 vs control) and the rate of total emergency visits by 47% (P < 0.0001 vs control). Analysis of demographic subgroups showed that the efficacy of omalizumab on asthma exacerbations was unaffected by patient age, gender, baseline serum IgE (split by median) or by 2‐ or 4‐weekly dosing schedule, although benefit in absolute terms appeared to be greatest in patients with more severe asthma, defined by a lower value of percentage predicted forced expiratory volume in 1 s (FEV1) at baseline. Conclusions:  These results suggest that omalizumab may fulfil an important need in patients with severe persistent asthma, many of whom are not adequately controlled on current therapy.

Fibroblast differentiation is an essential step during wound healing and fibrosis. Fibronectin (FN) is a major component of the extracellular matrix and occurs in two main forms: plasma and cellular FN. The latter includes the alternatively spliced domain A (EDA). Although EDA-containing cellular fibronectin (EDA-FN) is associated with fibroblast differentiation, how EDA-FN promotes differentiation is incompletely understood. In this study, we investigate the mechanism by which EDA-FN contributes to fibroblast differentiation with emphasis on the characterization of the EDA-FN receptor. We show that EDA-FN increases α-SMA expression (immunofluorescence), collagen deposition, cell contractility, and focal adhesion kinase (FAK) activation (immunoblotting); whereas plasma FN, a form lacking EDA, shows no effect. Primary lung fibroblasts constitutively express α(4)β(7) integrin receptor (FACS and RT-PCR). Blocking of α(4)β(7) reduces fibroblast adhesion to EDA-FN and inhibits α-SMA expression, collagen deposition, and FAK activation induced by EDA-FN. Using recombinant EDA-containing peptides, we demonstrate that the EDA segment is sufficient to induce fibroblast differentiation via binding to α(4)β(7). EDA-FN induces MAPK-Erk1/2 activation and inhibition of MEK1/2 attenuates EDA-FN-induced α-SMA expression. Our findings demonstrate that EDA-FN induces fibroblast differentiation by a mechanism that involves binding of EDA to α(4)β(7) integrin followed by activation of FAK and MAPK-associated signaling pathways.

No abstract

Background: Bronchial provocation tests such as exercise, methacholine (MCH), and adenosine-59-monophosphate (AMP) challenges are used extensively in the diagnosis of asthma. A study was undertaken to determine whether exhaled nitric oxide (eNO) can be used to diagnose asthma in patients with non-specific respiratory symptoms and to compare this test with conventional provocation tests. Methods: Patients with non-specific respiratory symptoms and normal spirometric parameters were included in the study. eNO was measured and exercise, MCH and AMP challenges performed in all subjects. Patients were defined as asthmatic based on clinical follow up 24 months after testing. Results: Forty patients were considered asthmatic and 45 were not. The area under receiver operating characteristic curves gave values of 0.896 for eNO, 0.781 for exercise, 0.924 for MCH, and 0.939 for AMP (p = 0.033, 0.575 and 0.085 for eNO v exercise, MCH and AMP respectively). From our data, a cut off value of NO .7 ppb at a flow rate of 250 ml/s best differentiates between asthmatics and nonasthmatics (sensitivity 82.5%, specificity 88.9%). Optimal cut off values for other tests were exercise: DFEV 1 >10% (sensitivity 57.9%, specificity 100%); PC 20 -MCH: (3 mg/ml (sensitivity 87.5%, specificity 86.7%); and PC 20 -AMP: (150 mg/ml (sensitivity 89.5%, specificity 95.6%). Conclusions: Measurement of eNO can be used as a safe, simple and rapid test for the diagnosis of asthma and is as good as bronchial provocation tests.

EDTA-dependent pseudothrombocytopenia (EDTA-PTCP) is the phenomenon of a spurious low platelet count due to the appearance of antibodies that cause platelet agglutination in blood anticoagulated with EDTA. We review here the clinical features of 18 patients with EDTA-PTCP treated in our hospital from 1984 to 1987 as well as those of 34 patients reported in the literature. This phenomenon appears more frequently in severely ill patients, in association with autoimmune, neoplastic, atherosclerosis-related, and liver diseases. In the majority of our patients, EDTA-PTCP appeared during hospitalization, indicating that the antibody is an acquired one. Neither splenomegaly nor the presence of autoimmune markers were features of this entity. Unlike true thrombocytopenias, EDTA-PTCP is associated with a normal mean platelet volume. Awareness of this entity is essential since EDTA-PTCP is frequently misdiagnosed and therefore incorrectly treated.