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C Picado

Publications and source records attributed to C Picado.

At least 37 records · Page 2Linked to original sources
PubMed2003

Nuclear factor-kappaB activity is down-regulated in nasal polyps from aspirin-sensitive asthmatics.

BACKGROUND: We examined whether a decreased activity of nuclear factor(NF)-kappaB), a transcriptional regulator of cyclooxygenase-2 (COX-2), could account for down-regulation of COX-2 in nasal polyps of aspirin-sensitive asthmatics. METHODS: Nasal polyps were obtained from 17 aspirin-intolerant asthma/rhinitis patients (AIAR; 7 men, mean age 48 +/- 12 years) and 23 aspirin-tolerant asthma/rhinitis patients (ATAR; 12 men, mean age 65 +/- 11 years). COX-2 mRNA expression was measured using semiquantitative reverse transcriptase competitive polymerase chain reaction (RT-PCR), and the results were expressed as mean +/- standard error of 106 molecules of mRNA/ micro g of total RNA. NF-kappaB binding was measured with 32P-labeled oligonucleotides and electrophoretic mobility shift assay (EMSA), and the results were expressed as a percentage with respect to the mean EMSA obtained in 19 healthy nasal mucosa. RESULTS: The mean levels of COX-2 mRNA expression (0.25 +/- 0.06) and NF-kappaB activity (89 +/- 13) in nasal polyps from AIAR were significantly lower than in polyps from ATAR (COX-2 = 1.58 +/- 0.50, and NF-kappaB = 143 +/- 12, P < 0.01 and P < 0.05, respectively). Levels of COX-2 mRNA and NF-kappaB activity in polyps from patients on corticosteroid therapy did not differ statistically from those who were not on this therapy before polypectomy. CONCLUSION: This study shows that the low expression of COX-2 mRNA in nasal polyps from aspirin-sensitive patients is associated with a down-regulation of NF-kappaB activity.

Adrenal Cortex Hormones↗
PubMed2003

Effect of montelukast added to inhaled budesonide on control of mild to moderate asthma.

BACKGROUND: Proinflammatory leukotrienes, which are not completely inhibited by inhaled corticosteroids, may contribute to asthmatic problems [corrected]. A 16 week multicentre, randomised, double blind, controlled study was undertaken to study the efficacy of adding oral montelukast, a leukotriene receptor antagonist, to a constant dose of inhaled budesonide. METHODS: A total of 639 patients aged 18-70 years with forced expiratory volume in 1 second (FEV(1)) > or =55% predicted and a minimum predefined level of asthma symptoms during a 2 week placebo run in period were randomised to receive montelukast 10 mg (n=326) or placebo (n=313) once daily for 16 weeks. All patients received a constant dose of budesonide (400-1600 microg/day) by Turbuhaler throughout the study. RESULTS: Mean FEV(1) at baseline was 81% predicted. The median percentage of asthma exacerbation days was 35% lower (3.1% v 4.8%; p=0.03) and the median percentage of asthma free days was 56% higher (66.1% v 42.3%; p=0.001) in the montelukast group than in the placebo group. Patients receiving concomitant treatment with montelukast had significantly (p<0.05) fewer nocturnal awakenings and significantly (p<0.05) greater improvements in beta agonist use and morning peak expiratory flow rate (PEFR). CONCLUSIONS: For patients with mild airway obstruction and persistent asthma symptoms despite budesonide treatment, concomitant treatment with montelukast significantly improves asthma control.

Acetates↗
PubMed2002

Frequency and clinical characteristics of rapid-onset fatal and near-fatal asthma.

The onset of fatal and near-fatal asthma attacks can be rapid. The objective of this study was to determine the frequency and clinical characteristics of rapid-onset asthma (ROA) in patients suffering fatal and near-fatal crises. Two-hundred and twenty patients with fatal or near-fatal attacks were enrolled in a multicentre, prospective study. ROA was defined as a crisis developing in < or =2 h. Data on patient and clinical characteristics were collected, and spirometric and allergy studies were performed when the patients were in a stable condition. Forty-five attacks (20%) were ROA and 175 (80%) were slow-onset asthma (SOA). The triggers for SOA and ROA attacks were different, with the ROA group having a significantly lower rate of suspected respiratory infection (7% versus 38%), higher rates of fume/irritant inhalation (9% versus 1%) and a higher intake of nonsteroidal antiinflammatory drugs (14% versus 3%). The ROA group exhibited significantly higher rates of impaired consciousness (63% versus 44%), absence of lung sounds upon admission (68% versus 42%), fewer hours of mechanical ventilation (13 h versus 28 h) and fewer days of hospitalization (8 days versus 9.5 days) than the SOA group. The 20% frequency of rapid-onset fatal and near-fatal attacks in this study suggests that rapidly developing attacks may not be rare. These findings also support a distinct clinical profile for rapid-onset asthma marked by differences in triggers, severity of exacerbation and clinical course.

Adult↗
PubMed2001

[Pilot study on knowledge about asthma and its treatment among Spanish teachers].

UNLABELLED: This was a study aimed to know the knowledge about asthma. SUBJECTS AND METHOD: 933 teachers of 27 schools from 7 cities (children aged between 4 and 15 years) using a self-administered questionnaire Half of them knew asthma prevalence and its hereditary nature. Nearly all related asthma with allergy, 38% with exercise, 25%had students who suffered from asthma attacks in the school, and 91% admitted to have limited information and wish to improve it. CONCLUSION: Our survey reveals that Spanish teachers have a limited information about asthma.

Adolescent↗
PubMed2001

Dietary micronutrients/antioxidants and their relationship with bronchial asthma severity.

BACKGROUND: Because little is known about micronutrient/antioxidant intake and asthma severity, we investigated dietary intake and plasma/serum levels of micronutrients/antioxidants in a group of asthma patients with various degrees of severity, and compared the results with healthy subjects. METHODS: A case control study was carried out on 118 asthma patients and 121 healthy subjects. The severity of the disease was classified by division of patients into four groups. Normal dietary micronutrient/antioxidant intake was estimated from a food frequency questionnaire. Plasma/serum levels of vitamins C, E, and A, selenium, magnesium, zinc, and platelet glutathione peroxidase (GSH-Px) activity were also determined. RESULTS: No differences in daily micronutrient/antioxidant intake were seen between patients and healthy subjects. The severity of the disease showed no significant relationship with micronutrient/antioxidant intake. There were no differences in plasma/serum levels in any of the micronutrients/antioxidants between healthy subjects and asthmatics. Nor were any differences found between asthma groups in severity in the biochemical measures, except in platelet GSH-Px activity, which was significantly lower in the most severe groups. CONCLUSIONS: In this study, we found no evidence of any association between micronutrient/antioxidant intake or plasma/serum levels of micronutrients/antioxidants and asthma. Reduction of platelet GSH-Px activity in the most severe patients suggests that these patients have a diminished capacity to restore part of the antioxidant defences.

Adolescent↗
PubMed2001

Effect of budesonide and nedocromil sodium on IL-6 and IL-8 release from human nasal mucosa and polyp epithelial cells.

We investigated the effect of budesonide and nedocromil sodium on the secretion of IL-6 and IL-8 by cultured epithelial cells from healthy nasal mucosa and nasal polyps. Human epithelial cell conditioned media was generated with fetal calf serum (FCS) in the presence or absence of budesonide and/or nedocromil sodium. Budesonide inhibited FCS-induced IL-6 and IL-8 release in a dose-dependent manner. The IC25 (25% inhibitory concentration) of budesonide on IL-6 release was higher in nasal polyp than in nasal mucosa epithelial cells (34 nM vs. 200 pM). The IC25 of budesonide on IL-8 release was higher in nasal mucosa than in nasal polyps (145 pM vs. 4 pM). Nedocromil sodium caused a dose-related inhibitory effect on IL-8 release from nasal mucosa (IC25, 207 nM), while it only had a significant effect in nasal polyps at 10(-5) M. Nedocromil sodium had no effect on IL-6 release. The inhibitory effect of budesonide was higher than that of nedocromil sodium on both nasal polyps and nasal mucosa. Budesonide and nedocromil sodium may exert their anti-inflammatory action in the respiratory mucosa by modulating the secretion of IL-6 and IL-8. The different effect of budesonide and nedocromil sodium on IL-6 and IL-8 release may be explained by differences in the mechanisms which regulate the upregulation of these cytokines in inflammatory responses.

Adolescent↗
PubMed2001

Proinflammatory cytokines and eosinophil cationic protein on glandular secretion from human nasal mucosa: regulation by corticosteroids.

BACKGROUND: Airway hypersecretion is a common finding in rhinitis and asthma in which proinflammatory cytokines are upregulated. The effect of inflammation on glandular secretion remains unclear. OBJECTIVE: We sought to investigate the effect of proinflammatory cytokines and eosinophil products in in vitro lactoferrin glandular secretion from human nasal mucosa and the role of corticosteroids and IL-10 in modulating this effect. METHODS: Nasal explants from patients undergoing turbinectomies were incubated in a controlled atmosphere (50% N(2), 5% CO(2), and 45% O(2)) at 37 degrees C. Nasal explants were incubated with or without IL-1beta, IL-4, IL-5, IL-8, eotaxin, GM-CSF, TNF-alpha, eosinophil cationic protein (ECP), IL-10, and budesonide in a time-course and dose-response fashion. Lactoferrin concentrations in culture supernatants were measured by means of ELISA. RESULTS: ECP (up to 30%) caused a dose-related stimulation of lactoferrin secretion. TNF-alpha (20 ng/mL) induced a significant increase of lactoferrin release from 8 hours (27.7% +/- 17.8%, P <.05) to 24 hours (40.8% +/- 17.2%, P <.01) compared with that found in media-treated explants. At 24 hours, TNF-alpha caused a dose-related stimulation of lactoferrin secretion (up to 35%). IL-1beta (65.3% +/- 15.2%, P <.05) and GM-CSF (15.7% +/- 6.7%, P <.05), both at 20 ng/mL, exerted a stimulatory effect only at 24 hours, and IL-4, IL-5, IL-8, and eotaxin had no significant effect. Budesonide caused a dose-related inhibition of lactoferrin secretion induced by IL-1beta (down to -76%) and TNF-alpha (down to -70%), whereas IL-10 had no effect. CONCLUSIONS: ECP and some proinflammatory cytokines (IL-1beta, TNF-alpha, and GM-CSF) may contribute to glandular hypersecretion in the inflamed nose. Corticosteroids may reduce nasal hypersecretion by blocking the direct effect of proinflammatory cytokines on glandular output.

Adult↗
PubMed2001

Bone mineral density in subjects with mild asthma randomised to treatment with inhaled corticosteroids or non-corticosteroid treatment for two years.

BACKGROUND: Inhaled corticosteroids are clearly beneficial for patients with asthma of moderate severity, but the risks and benefits of using them in patients with milder asthma are less clear. We have compared the change in bone mineral density over 2 years in adults with mild asthma randomised to receive an inhaled corticosteroid or non-corticosteroid treatment. METHODS: Subjects with mild asthma (mean forced expiratory volume in one second (FEV(1)) 86% predicted, mean age 35 years, taking beta agonists only) were randomised to receive inhaled budesonide, inhaled beclomethasone dipropionate, or non-corticosteroid treatment for 2 years in a prospective randomised open study in 19 centres in France, New Zealand, Spain, and the UK. The corticosteroid dose was adjusted according to a written self-management plan. The main outcome measure-change in bone mineral density after 6, 12, and 24 months-was measured "blind". Secondary outcomes included lung function, the relation between change in bone density and inhaled steroid dose and change in biochemical markers of bone metabolism. RESULTS: Of 374 subjects randomised, 239 (64%) completed the study and were included in the analysis. The median daily doses of inhaled budesonide (n=87) and beclomethasone (n=74) were 389 microg and 499 microg, respectively. Subjects treated with an inhaled corticosteroid had better asthma control than those in the reference group (n=78). Change in bone mineral density did not differ between the three groups over the 2 years, nor did it correlate with changes in markers of bone metabolism. The mean change in bone mineral density over 2 years in the budesonide, beclomethasone dipropionate, and reference groups was 0.1%, -0.4%, and 0.4% for the lumbar spine and -0.9%, -0.9%, and -0.4% for neck of the femur. Mean daily dose of inhaled steroid was related to reduction in bone mineral density at the lumbar spine but not at the femoral neck. CONCLUSION: In subjects with mild asthma an inhaled corticosteroid provided better asthma control than alternative non-corticosteroid treatment with no difference in change in bone mineral density over 2 years. The relation between dose of inhaled corticosteroid and change in bone density at the lumbar spine may be due to a direct effect of inhaled corticosteroids on bone. Since inhaled steroid dose is also related inversely to lung function, an effect of asthma severity on bone density was also possible.

Administration, Inhalation↗
PubMed2001

Expression of the human glucocorticoid receptor alpha and beta isoforms in human respiratory epithelial cells and their regulation by dexamethasone.

Two isoforms of the human glucocorticoid receptor (hGR) have been described, hGRalpha and hGRbeta. We analyzed the expression and regulation of both hGR isoforms in human respiratory epithelial cells (BEAS-2B, A549, and primary nasal epithelial cells). In BEAS-2B cells, the expression of hGRalpha messenger RNA (mRNA) was much higher than that of hGRbeta mRNA. Dexamethasone (DEX) (10(-6) M) downregulated hGRalpha mRNA at 6 and 24 h (55 +/- 8 and 58 +/- 5% of control, respectively; P < 0.01), whereas it decreased hGRbeta mRNA only at 6 h (55 +/- 7% of control; P < 0.01). Downregulation of hGRalpha and hGRbeta mRNAs occurred even in the presence of cycloheximide. Actinomycin-D studies revealed that DEX enhanced the stabilization of hGRalpha and hGRbeta messages. hGRalpha but not hGRbeta protein was detected in BEAS-2B, A549, and nasal epithelial cells. After 24 h of incubation, 10(-6) M DEX decreased the expression of hGRalpha protein in BEAS-2B, A549, and nasal epithelial cells (16 +/- 4, 14 +/- 4, and 28 +/- 7% of control, respectively; P < 0.01). These results suggest that in respiratory epithelial cells: (1) hGRalpha is much more expressed than hGRbeta at both the mRNA and protein levels; (2) hGRalpha is downregulated by corticosteroids both in cell lines (BEAS-2B, A549) and in nasal primary cells; and (3) transcriptional, post-transcriptional, and post-translational mechanisms appear to be involved in the regulation of hGR expression by corticosteroids.

Animals↗
PubMed2000

Regulation of cyclooxygenase-1 and -2 expression in human nasal mucosa. Effects of cytokines and dexamethasone.

BACKGROUND: Cyclooxygenase (COX) converts arachidonic acid in prostanoids. COX exists in two isoforms, COX-1 is the constitutive whereas COX-2 is the inducible isoform. The regulation of COX-1 and COX-2 expression in nasal mucosa has not been previously reported. AIM: We studied expression and regulation by cytokines and corticosteroids of COX-1 and COX-2 in human nasal mucosa. Cultured human nasal explants from patients undergoing corrective nasal mucosal resection were examined for COX-1 and COX-2 expression by semiquantitative competitive PCR and Western blot. METHODS: Explants were incubated with pro-(IFNgamma, IL-1beta, and TNF-alpha) and anti(IL-10) inflammatory cytokines and dexamethasone. The mechanisms which regulate COX-2 mRNA expression were studied using inhibitors of translation (Actinomycin D) and transcription (Cicloheximide). RESULTS: The baseline expression of COX-2 mRNA was higher than COX-1 mRNA. Once in culture, there was a slight spontaneous up-regulation of COX-1 and a strong COX-2 mRNA and protein up-regulation. The incubation of nasal explants with pro-inflammatory cytokines increased the expression of COX-2 mRNA and protein, from 1 to 24 h of incubation in a dose-related manner. The regulation of these effects occurred at both transcriptional and post-transcriptional levels. Dexamethasone and IL-10 abrogated cytokine-induced COX-2 mRNA and protein expression. Pro-inflammatory cytokines, dexamethasone and IL-10 had no effect on COX-1 mRNA expression. CONCLUSIONS: As prostanoids have important regulatory effects on the immunologically mediated inflammatory responses, our findings throw some light on the mechanisms that regulate the enzymes which produce these metabolites in the human airway.

Adult↗
PubMed2000

Inhibition of GM-CSF secretion by topical corticosteroids and nedocromil sodium. A comparison study using nasal polyp epithelial cells.

Nasal epithelial cells maintain eosinophil survival by secreting granulocyte/macrophage colony-stimulating factor (GM-CSF). Corticosteroids antagonize eosinophil viability induced by GM-CSF. We investigated the effect of topical corticosteroids and nedocromil sodium on the release of GM-CSF from nasal polyp epithelial cells. Epithelial cells were obtained from 19 patients undergoing nasal polypectomy and cultured. After reaching confluence, cultured cells were stimulated with 10% foetal calf serum in the absence and presence of four topical corticosteroids and nedocromil sodium for 48 h. GM-CSF was measured by enzyme linked immunosorbent assay (ELISA). Fluticasone propionate was the most potent inhibitor of GM-CSF release (IC25 = 46 pM) closely followed by budesonide (IC25 = 4 nM), beclomethasone dipropionate (IC25 = 40 nM) and triamcinolone acetonide (IC25 = 75 nM). Nedocromil sodium had no effect on GM-CSF release. We conclude that the effect of topical steroids on reducing eosinophil infiltration in nasal polyps may be due in part to downregulation, among other cytokines, of epithelial GM-CSF production which prolongs eosinophil viability. Quantitatively, fluticasone propionate inhibited GM-CSF production more potently than budesonide, beclomethasone dipropionate and triamcinolone acetonide.

Administration, Topical↗
PubMed2000

Evaluation of CD30 as a marker for th2 lymphocytes in bronchoalveolar lavage in interstitial lung diseases.

Several studies have been carried out to clarify the relationship between CD30 expression and Th2 lymphocytes, although the results have been controversial. To investigate whether CD30 is a useful marker for Th2 lymphocytes in bronchoalveolar lavage (BAL) in interstitial lung diseases (ILD), we studied six control subjects and 31 patients with ILD (12 with idiopathic pulmonary fibrosis, seven with hypersensitivity pneumonitis, three with chronic eosinophilic pneumonia and nine with sarcoidosis). The levels of interleukin-5 (IL-5) (secreted by Th2 cells), interferon-gamma (IFNgamma) (secreted by Th1 cells) and the expression of CD30 on lymphocytes were determined in BAL fluid. There were no differences in the percentage of CD30+ lymphocytes between controls and patients with ILD (0.8+0.4% vs. 2+/-0.4%). In order to determine the relationship between Th2 cells and CD30 expression, we divided the patients into two groups according to BAL IL-5 levels. Group I consisted of eight patients (three chronic eosinophilic pneumonia, three hypersensitivity pneumonitis, two idiopathic pulmonary fibrosis) with high IL-5 levels (298+/-138 pg ml(-1)). Group II consisted of the remaining 23 ILD patients with normal IL-5 levels (0.9+/-0.6 pg ml(-1)). The percentage of eosinophils in BAL fluid was significantly higher in group I compared with group 11 (34+/-16% vs. 3+/-1%, P < 0.05). A correlation between CD30+ lymphocytes and IL-5 in group 1 was not shown. There were no differences in the number of CD30+ I we found a significant correlation between IL-5 levels and the percentage of eosinophils (r = 0.95, P < 0.0001). Our results suggest that CD30 does not appear to be a useful marker for Th2 lymphocytes in BAL from patients with ILD.

Adult↗
PubMed2000

Montelukast or salmeterol combined with an inhaled steroid in adult asthma: design and rationale of a randomized, double-blind comparative study (the IMPACT Investigation of Montelukast as a Partner Agent for Complementary Therapy-trial).

Asthma patients who continue to experience symptoms despite taking regular inhaled corticosteroids represent a management challenge. Leukotrienes play a key role in asthma pathophysiology, and since pro-inflammatory leukotrienes are poorly suppressed by corticosteroids it seems rational to add a leukotriene receptor antagonist (LTRA) when a low to moderate dose of inhaled corticosteroids does not provide sufficient disease control. Long acting beta2-agonist (LABA) treatment represents an alternative to LTRAs and both treatment modalities have been shown to provide additional disease control when added to corticosteroid treatment. To compare the relative clinical benefits of adding either a LTRA or a LABA to asthma patients inadequately controlled by inhaled corticosteroids, a randomized, double-blind, multi-centre, 48-week study will be initiated at approximately 120 centres throughout Europe, Latin America, Middle East, Africa and the Asia-Pacific region in early 2000. The study will compare the oral LTRA montelukast with the inhaled LABA salmeterol, each administered on a background of inhaled fluticasone, on asthma attacks, quality of life, lung function, eosinophil levels, healthcare utilization, and safety, in approximately 1200 adult asthmatic patients. The requirements for study enrollment include a history of asthma, FEV1 or PEFR values between 50% and 90% of the predicted value together with > or = 12% improvement in FEV1 after beta-agonist administration, a minimum pre-determined level of asthma symptoms and daily beta-agonist medication. The study will include a 4-week run-in period, during which patients previously taking inhaled corticosteroids are switched to open-label fluticasone (200 microg daily), followed by a 48-week double-blind, treatment period in which patients continuing to experience abnormal pulmonary function and daytime symptoms are randomized to receive montelukast (10 mg once daily) and salmeterol placebo, or inhaled salmeterol (100 microg daily) and montelukast placebo. All patients will continue with inhaled fluticasone (200 microg daily). During the study, asthma attacks, overnight asthma symptoms, and morning peak expiratory flow rate will be assessed using patient diary cards; quality of life will also be assessed using an asthma-specific quality-of life questionnaire. The results of this study are expected to provide physicians with important clinical evidence to help them make a rational and logical treatment choice for asthmatic patients experiencing breakthrough symptoms on inhaled corticosteroids.

Acetates↗