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Biomedical subjects

G W Canonica

Publications and source records attributed to G W Canonica.

At least 19 recordsLinked to original sources

Introduction to nasal and pulmonary allergy cascade.

The early phase of an IgE-dependent allergic reaction is followed by the activation of a complex network of inflammatory phenomena - T lymphocytes, cytokines, mediators, and adhesion molecules - that mediate late and ongoing allergic symptoms. The kinetics of respiratory inflammation following allergen exposure involve the migration of inflammatory cells to the mucosa within about 30 min, increased inflammatory infiltration over the following hours, and then slow subsidence. A relationship between asthma and allergic rhinitis is supported by epidemiological, histological, physiological, and immunopathological data, and by the response of asthma symptoms in rhinitic patients to intranasal corticosteroids and antihistamines. For example, there is no morphological difference between the bronchial inflammatory response following allergen-specific challenge in patients suffering from asthma alone or rhinitis alone. It is the allergen dose that makes the difference in the airway response to allergen in allergic rhinitis and asthma. Recognition of the relationship between asthma and allergic rhinitis has led to the introduction of new diagnostic terminology and treatment recommendations: 1) patients with persistent rhinitis should be evaluated for asthma; 2) patients with persistent asthma should be evaluated for rhinitis; and 3) a strategy should combine the treatment of upper and lower airways in terms of efficacy and safety.

Asthma↗

Cytokine pattern in allergic and non-allergic chronic rhinosinusitis in asthmatic children.

BACKGROUND: Rhinosinusitis represents one of the most common chronic diseases. The association of rhinosinusitis with asthma has been frequently reported. Eosinophils and Th2 cells play a pathogenic mechanism in asthma. OBJECTIVE: The aims of the study were to evaluate the cytokine pattern in chronic rhinosinusitis in asthmatic children and to compare the findings in allergic vs. non-allergic asthmatics. METHODS: Thirty-five asthmatic children were evaluated, 19 males and 16 females, with an average age of 8.7 years. All children were asthmatic and suffered from chronic rhinosinusitis. Twenty were allergic and 15 were non-allergic. Ten healthy children were studied as normal controls. Evaluated parameters were the levels of the following cytokines: IL-1beta, IL-4, IL-6, IL-8, IL-12, IFN-gamma and TNF-alpha. Cytokines were recovered from rhinosinusal lavage and measured by immunoassays. Nasal cytology was also performed in all subjects and inflammatory cells were counted by conventional staining. RESULTS: Allergic subjects showed a significant increase of IL-4 (P < 0.01) and TNF-alpha (P < 0.05) and a significant decrease of IL-12 (P < 0.05) and of IFN-gamma (P < 0.0001), whereas IL-1beta, IL-6 and IL-8 were not significantly increased. Non-allergic children showed a significant increase of IL-4 (P < 0.05) and a significant decrease of IFN-gamma (P < 0.0001), IL-12 was not significantly decreased, and IL-1beta, IL-6 and IL-8 were not significantly increased. A significant inflammatory infiltrate was present in all asthmatic children. Significant correlations were demonstrated between IL-4 and IL-12 (P < 0.001), IL-12 and IFN-gamma (P < 0.001), IL-8 and neutrophils (P < 0.01), and TNF-alpha and monocytes/macrophages (P < 0.05), in allergic asthmatics. IL-4 and IL-12 were significantly correlated (P < 0.05) as well as IL-8 and neutrophils (P < 0.01) in non-allergic asthmatics. CONCLUSION: This study shows that allergic asthmatic children with chronic rhinosinusitis have a typical Th2 cytokine pattern, but also non-allergic asthmatic children share a similar pattern. These findings would suggest the existence of a common pathophysiological mechanism shared by upper and lower airways and are consistent with the concept of united airways disease.

Asthma↗

Effects of triamcinolone acetonide on adult human lung fibroblasts: decrease in proliferation, surface molecule expression and mediator release.

BACKGROUND: Lung fibroblasts may have a pivotal role in airway inflammation as they are involved in continuous cycles of mediator secretion, proliferation, activation and cross-talk with recruited inflammatory cells. The role of fibroblasts as intermediate participants in the inflammatory network suggests that they could represent an important target for drugs commonly used in asthma; thus, we investigated the effects of triamcinolone acetonide (TAA) on primary human lung fibroblasts. METHODS: The in vitro activity of increasing concentrations (10(-9) to 10(-7) M) of TAA in fibroblast cultures was evaluated as regards the following parameters: proliferation, extracellular matrix (ECM) release, cytokine/chemokine secretion and surface antigen expression. RESULTS: All concentrations of TAA decreased fetal calf serum (FCS)-induced fibroblast proliferation, whereas in the presence of FCS plus basic fibroblast growth factor TAA was only effective at 10(-8) and 10(-7) M. TAA failed to decrease ECM, whereas at 10(-8) and 10(-7) M it decreased IL-6 and IL-8 secretion to different extents. In the presence of IFN-gamma the drug was able to reduce VCAM-1 expression at all of the tested concentrations; on the other hand, in TGF-beta 1-driven cultures a decrease in CD54 expression was detected with TAA at 10(-8) and 10(-7) M. CONCLUSIONS: TAA acts on some functional properties of human lung fibroblasts that make these cells active participants in the inflammatory network. The ability of TAA to inhibit lung fibroblast proliferation may prevent or even reverse some of the histological changes that characterize airway remodeling in chronic inflammatory diseases; moreover, IL-6, IL-8 and surface molecule decreases by TAA may suggest a direct anti-inflammatory effect of the drug by suppression of resident lung cell function.

Cell Division↗

The inflammatory network.

In the last few years the findings on allergic inflammation have improved, particularly in cellular signaling. Now we know that cytokines and other mediators are a network able to regulate the allergic inflammation (and inflammation in general). The new findings are important not only for basic science but also for the development of new therapeutic approaches to allergic diseases.

Humans↗

Novel anti-inflammatory effects of the inhaled corticosteroid fluticasone propionate during lung myofibroblastic differentiation.

Asthma is characterized by an irreversible subepithelial fibrosis with the appearance of myofibroblasts, which can be now considered important early participants in inflammatory responses as well as potential targets for anti-inflammatory drugs. In this study, we show that fluticasone propionate (FP), a powerful inhaled corticosteroid (ICS), displays novel anti-inflammatory effects on human lung fibroblasts during their myofibroblastic differentiation. Indeed, FP inhibits in lung myofibroblasts, at a very early stage of differentiation, the activation of Janus kinase/STAT pathways induced by IL-13 (tyrosine kinase 2, STAT1, STAT3, STAT6, mitogen-activated protein kinase). Contrarily, in mildly or fully differentiated myofibroblastic cultures, FP still displays a potential anti-inflammatory activity even if it only inhibits tyrosine kinase 2 phosphorylation. Moreover, FP inhibits constitutive and TGF-beta-induced expression of alpha-smooth muscle actin, the main marker of myofibroblastic differentiation, both in very early and in mild differentiated myofibroblasts. Finally, FP displays an additional powerful anti-inflammatory effect, decreasing nuclear translocation of NF-kappaB independent of the degree of myofibroblastic differentiation. These data 1) suggest that myofibroblasts are priority targets for ICS, which is able to revert them to a normal phenotype even if they appear to be already engaged in their differentiation, and 2) may help to explain why asthma is improved by an early ICS treatment, whereas advanced asthma is more resistant to these drugs.

Actins↗

Impact of rhinitis on airway inflammation: biological and therapeutic implications.

There is increasing evidence for a close link between the upper and the lower respiratory tracts and the fact that rhinitis has an important impact on asthma. Several clinical and experimental observations suggest a similar immunopathology between the upper and lower airways in allergic subjects. The common inflammatory process that develops in the respiratory tract explains some of the complex interactions among different clinical diseases such as rhinitis, sinusitis, asthma, bronchial hyperresponsiveness and viral infections. There are also non-inflammatory mechanisms that may contribute to the link between rhinitis and asthma. Moreover, the outcomes of various pharmacological treatments of rhinitis have recently provided further support for the hypothesis of the united airways. We discuss some of the recent observations on the nose-lung interaction and some of the novel therapeutic approaches used to treat rhinitis and asthma that arise from this.

Asthma↗

Long-term cetirizine treatment reduces allergic symptoms and drug prescriptions in children with mite allergy.

BACKGROUND: Experimental data demonstrate that mite allergy is characterized by persistent chronic inflammation, even during asymptomatic periods. This suggests that long-term continuous treatment be included in the global strategy of allergy treatment. OBJECTIVE: We conducted a study to evaluate whether regularly administered cetirizine reduces allergic symptoms and drug prescriptions in children with mite allergy. METHODS: In this double-blind, randomized, placebo-controlled study, two parallel groups of 10 children with mite allergy (mean age: 6.5 years) received either cetirizine or placebo daily for 6 months. Participants were allowed to take rescue medications for rhinitis and/or mild asthma. The symptoms (nasal itching, sneezing, obstruction, rhinorrhea, conjunctival itching, lacrimation, conjunctival hyperemia, cough, wheezing, and chest tightness) were recorded on a diary card. The intake of cetirizine (as additional symptomatic treatment), antibiotics, acetaminophen, beta2-agonists, inhaled and systemic corticosteroids was also recorded. RESULTS: Symptom scores and drug consumption were significantly lower (P < 0.05) in the cetrizine-treated group versus the placebo group. The greatest reductions were in cetirizine itself, inhaled corticosteroids, beta2-agonists, and antibiotics. No side effects were reported in either group. CONCLUSIONS: In mite-allergic children, cetirizine administered daily for prolonged periods decreases symptoms of and drug prescriptions for allergic rhinitis and asthma compared with symptomatic treatment.

Allergens↗

Intranasal mometasone furoate reduces late-phase inflammation after allergen challenge.

BACKGROUND: Allergen specific nasal challenge (ASNC) is an optimal model to study the pathophysiologic mechanisms sustaining allergic inflammation, particularly the adhesion molecules promoting cellular infiltration of nasal mucosa. Topical corticosteroids have been accepted as a highly effective anti-inflammatory therapy for allergic rhinitis. OBJECTIVE: The aim of this double-blind, randomized, placebo-controlled study was the evaluation of inflammatory events, during the late-phase, after a 2-week treatment with nasal mometasone furoate (MF), 200 microg daily, or placebo, using the model of ASNC. METHODS: A total of 42 patients with allergic rhinitis underwent nasal challenge before and after treatment. The following parameters were evaluated at baseline, and 6 hours (late-phase) after ASNC: 1) nasal symptoms (rhinorrhea, itching, sneezing, obstruction); 2) inflammatory cells (eosinophils and neutrophils); 3) eosinophil cationic protein (ECP) and tumor necrosis factor-alpha (TNF-alpha) in nasal lavage; and 4) intercellular adhesion molecule-1 expression on nasal epithelial cells. RESULTS: MF nasal spray was associated with late-phase reductions of: 1) clinical symptoms (P < 0.03); 2) eosinophil (P < 0.004) and neutrophil (P < 0.003) infiltration; 3) ECP (P < 0.001) and TNF-alpha (P < 0.05); and 4) intercellular adhesion molecule-1 expression on nasal epithelial cells (P < 0.001). CONCLUSIONS: The present results demonstrate that MF has a significant effect on late-phase events, reducing the cellular influx and activation.

Administration, Intranasal↗

Safety of sublingual immunotherapy with monomeric allergoid in adults: multicenter post-marketing surveillance study.

BACKGROUND: Sublingual immunotherapy (SLIT) appears to be acceptably safe in clinical trials, but post-marketing data are needed to provide essential information. This study specifically evaluated the safety of commercial SLIT in adult patients in a post-marketing phase. METHODS: A total of 198 patients (83 male, 115 female, mean age 24.4 years) receiving SLIT for respiratory allergy were followed up for 3 years by a specific questionnaire for side-effects. SLIT (LAIS, Lofarma SpA, Milan, Italy), a monomeric allergoid in tablets, was administered, in association with drug therapy, pre- or pre-coseasonally for pollen and continuously for mites. The average duration was 12-36 months, and the total of doses was about 32 800. Side-effects were grouped as ocular, gastrointestinal, rhinitis, asthma, urticaria, edema of tongue/lips, and anaphylaxis. The severity was graded as low (no need for treatment or dose adjusting, no interference with activities), moderate (interference with activities/need for drugs/SLIT discontinuation), and severe (life-threatening/hospitalization/emergency care). RESULTS: Seventeen events corresponding to 7.5% of patients and 0.52 per 1000 doses were reported. Seven episodes of rhinitis (two in two patients), three of oral itching, and one of abdominal pain were self-limiting. Two cases of urticaria and two of abdominal pain/nausea were controlled by a temporary dose-adjustment, and one case of urticaria and conjunctivitis required oral antihistamines. Medical intervention was needed in six patients only during a 3-year period. CONCLUSION: The results of this study, performed in a real situation of clinical practice, confirm the satisfactory safety profile of SLIT.

Administration, Sublingual↗

Fexofenadine reduces nasal congestion in perennial allergic rhinitis.

BACKGROUND: Nasal congestion is the predominant symptom in perennial allergic rhinitis (PAR), and it seems to be mainly related to the late-phase inflammatory events. The present pilot study aimed to evaluate the therapeutic effect exerted by fexofenadine in patients with PAR due to mite allergy. METHODS: This study was a parallel, double-blind, randomized, three-arm (1:1:1), placebo-controlled study. Thirty-one subjects with PAR were enrolled and received double-blind medication: fexofenadine 120 or 180 mg, or placebo, once a day for 28 days. RESULTS: The total symptom score was reduced by fexofenadine (both dosages) at V2 (P=0.007), whereas placebo did not modify it. Nasal congestion decreased after 1 week of treatment with fexofenadine 120 (P=0.027) and 180 (P=0.01), but not with placebo (P=NS). At V3, fexofenadine (both dosages) significantly reduced nasal congestion (P=0.011 and P=0.007, respectively), by placebo did not show any significant effect. CONCLUSIONS: This pilot study represents the first evidence of the efficacy of fexofenadine in PAR, and also the control of the nasal congestion. We suggest performing larger trials to confirm these preliminary findings.

Adolescent↗

Sublingual tryptase and ECP in children treated with grass pollen sublingual immunotherapy (SLIT): safety and immunologic implications.

BACKGROUND: The clinical safety of sublingual immunotherapy (SLIT) has been repeatedly confirmed; nevertheless, the possible onset of local oral symptoms is still a concern, and nothing is known about the pathogenesis of this effect. We aimed to determine whether the administration of SLIT in allergic children can evoke an IgE-mediated reaction, by measuring the levels of sublingual tryptase and ECP. METHODS: Thirty children (7-12 years old) with allergic rhinitis/asthma due to grass pollen were prescribed SLIT. In these children, an allergen-specific nasal challenge was performed, and nasal tryptase and ECP were measured before and after. Sublingual ECP and tryptase were also assessed before the SLIT, after 1 month, and after 6 months of treatment. Ten matched allergic children and 10 healthy ones served as controls for the baseline levels of sublingual ECP and tryptase. RESULTS: The levels of nasal tryptase and ECP significantly increased after nasal challenge (P<0.001), whereas no change during the SLIT course (at the beginning, after 1 month, and after 6 months) could be detected in sublingual tryptase either before or after SLIT administration. The sublingual ECP significantly decreased after 6 months of SLIT. The baseline levels of nasal tryptase and ECP were significantly higher in allergic subjects than in healthy controls, as was the level of sublingual ECP. CONCLUSIONS: In the presence of an IgE-mediated reaction (ASNC), a significant increase of tryptase and ECP can be seen. When SLIT is administered, such a phenomenon does not occur; therefore, SLIT does not elicit any IgE reaction in the mouth. It is noteworthy that allergic subjects display higher levels of nasal ECP and tryptase than healthy subjects, even when symptom-free, and these observations may indicate the presence of subclinical inflammation.

Administration, Sublingual↗