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1.
J Physiol Pharmacol ; 66(5): 635-42, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26579569

RESUMO

Sarcoidosis is a multi-organ disease in which affected tissues are invaded with non-necrotizing granulomatous structures, mostly consisted of T helper 1 (Th1) cells and multinucleate giant cells. However, the etiology and pathogenesis of sarcoidosis is not known and the diagnosis is usually based on clinical examination involving radiography and histopathological analysis of biopsies of affected organs. Although the knowledge on the molecular background of sarcoidosis is limited, it seems that the important pathways involve transforming growth factor-ß (TGF-ß) and JAK/STAT, which may influence the interferon-γ (IFN-γ)-mediated signaling. Additionally, recently the role of microRNAs (miRNAs), the small non-coding RNA molecules, has been emphasized in different pathological conditions including autoimmune diseases. This review summarizes the current knowledge on the molecular pathways in the pathogenesis of sarcoidosis with a special emphasis on cytokines and miRNAs controlling immune cells proliferation and differentiation. Moreover, the possible role of T regulatory cells (CD4(+) CD25(+) FoxP3(+)) in this disease has been discussed.


Assuntos
Inflamação/patologia , MicroRNAs/genética , Sarcoidose Pulmonar/fisiopatologia , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Citocinas/metabolismo , Humanos , Inflamação/genética , Sarcoidose Pulmonar/genética , Linfócitos T Reguladores/metabolismo
2.
Nano Lett ; 14(9): 4977-81, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25118624

RESUMO

We report on the fabrication and characterization of symmetric nanowire-based Josephson junctions, that is, Al- and Nb-based junctions, and asymmetric junctions employing superconducting Al and Nb. In the symmetric junctions, a clear and pronounced Josephson supercurrent is observed. These samples also show clear signatures of subharmonic gap structures. At zero magnetic field, a Josephson coupling is found for the asymmetric Al/InAs-nanowire/Nb junctions as well. By applying a magnetic field above the critical field of Al or by raising the temperature above the critical temperature of Al the junction can be switched to an effective single-interface superconductor/nanowire structure. In this regime, a pronounced zero-bias conductance peak due to reflectionless tunneling has been observed.

3.
Nanotechnology ; 24(8): 085603, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23385879

RESUMO

We report on the technology and growth optimization of GaAs/InAs core/shell nanowires. The GaAs nanowire cores were grown selectively by metal organic vapor phase epitaxy (SA-MOVPE) on SiO(2) masked GaAs (111)B templates. These were structured by a complete thermal nanoimprint lithography process, which is presented in detail. The influence of the subsequent InAs shell growth temperature on the shell morphology and crystal structure was investigated by scanning and transmission electron microscopy in order to obtain the desired homogeneous and uniform InAs overgrowth. At the optimal growth temperature, the InAs shell adopted the morphology and crystal structure of the underlying GaAs core and was perfectly uniform.

4.
Allergy ; 58(10): 1064-6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14510727

RESUMO

BACKGROUND: Acetylsalicylic acid (ASA) and other nonsteroid anti-inflammatory drugs (NSAIDs) are reported to account for 21-25% of all adverse drug reactions. Some asthmatics may react to ASA and other NSAIDs with acute bronchoconstriction, profuse rhinorrhea and skin flushing. This is a distinct clinical syndrome called aspirin-induced asthma (AIA). The prevalence of AIA among asthmatic patients in Poland has not been previously assessed. METHODS: A questionnaire survey of 12,970 adults of both sexes, randomly selected from the population of Poland. RESULTS: The prevalence of AIA in the general population of Poland was estimated as 0.6%. Thirty patients (4.3%; 95% CI: 2.8-5.8) of 703 asthmatics (5.4% of general population) reported symptoms attesting to hypersensitivity to aspirin. In 27% of them the reactions were precipitated by aspirin, whereas in the remaining subjects by other NSAIDs. CONCLUSIONS: The prevalence of AIA in Poland is 4.3%, being somewhat lower than in Finland and Australia, where it was recently reported to account for 8.8 and 10.9% of the adult asthmatics, respectively. These figures indicate that aspirin hypersensitivity might be a significant community problem.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Asma/induzido quimicamente , Hipersensibilidade a Drogas/epidemiologia , Adolescente , Adulto , Idoso , Asma/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Polônia/epidemiologia , Prevalência
5.
Respir Med ; 97 Suppl D: S10-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14753247

RESUMO

The aim of the present study was to demonstrate an equivalent asthma control and safety of inhaled budesonide 200 microg unit-dose via a spacer device (Jet Spacer, Chiesi Farmaceutici S.p.A.) given with an HFA-134a or CFC propellant in stable patients treated with inhaled corticosteroids. A total number of 270 patients, 134 in the HFA-134a group and 136 in the CFC group, completed a 2-week run-in period and were then randomised to receive a daily dose of inhaled budesonide (low dose: 400 microg, medium dose: 800 microg, high dose: 1200 or 1600 microg), defined on the basis of the dose of previous inhaled steroids given twice daily for 12 weeks. Morning and evening PEFR, intake of rescue salbutamol, number of day-time and night-time asthma attacks, number of night-time awakenings due to asthma and clinical symptoms were recorded daily by patients on diary cards. Pulmonary function tests (FEV1, FVC, PEFR and MEF50) and vital signs were measured at the clinics at study entry, at the start of treatment and after 2, 4, 8 and 12 weeks thereafter. Morning serum cortisol (8.00-10.00 AM) was measured at baseline and in the final visit. Adverse events and vital signs were recorded throughout the total study period. Small increases vs. baseline for lung function (more markedly in the high-dose subsets) and significant decreases of symptoms and use of rescue salbutamol were similarly observed in both groups. Equivalence was demonstrated for the primary endpoint morning PEFR (difference between means = -1.51 l/min; 95% CI: -9.40-6.37 l/min; pre-defined limits: +/- 42.16 l/min, i.e. +/- 10% of the reference LSM) as well as for evening PEFR and FEV1, both in the ITT population or on a per-protocol basis. No statistically significant differences between groups were observed in any of the other efficacy variables. A similar proportion of drug-related adverse events was observed in the two groups, without drug-related serious events in either group. No evidence of adrenal depletion was also noted with both propellants. In conclusion, the budesonide HFA-134a formulation given with a spacer device provided an equivalent asthma control with that of a corresponding CFC product, when administered in stable patients treated with inhaled corticosteroids in a broad range of daily doses. The use of the new propellant did not modify the safety profile of inhaled budesonide.


Assuntos
Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Budesonida/administração & dosagem , Administração por Inalação , Adulto , Propelentes de Aerossol/administração & dosagem , Idoso , Antiasmáticos/efeitos adversos , Budesonida/efeitos adversos , Clorofluorcarbonetos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , Hidrocarbonetos Fluorados/administração & dosagem , Masculino , Inaladores Dosimetrados , Pessoa de Meia-Idade , Ventilação Pulmonar/efeitos dos fármacos , Resultado do Tratamento
6.
Respir Med ; 96(10): 784-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12412977

RESUMO

This study was carried out with the aim of demonstrating the efficacy and tolerability of beclomethasone dipropionate (BDP) aerosol spray 500 microg b.i.d. via a spacer device (Jet, Chiesi Farmaceutici S.p.A.) using a new HFA-134a formulation or chlorofluorocarbon (CFC) propellant. After having completed a 2-week run-in period, 154 adult patients (77 in each group) with mild-to-moderate persistent asthma were randomised into two groups to receive the study treatment for a duration of 12 weeks in a double-blind, multinational, multicentre, parallel-group design. Morning and evening peak expiratory flow rate (PEFR), use of rescue salbutamol, number of day- and night-time asthma attacks, number of night-time awakenings due to asthma and clinical symptoms were recorded daily by patients on diary cards. Pulmonary function tests (FEV1, FVC, PEFR, FEF25-75%, MEF50 and FEF25) and vital signs were measured at the clinic at study entry, at the start of treatment and every 2 weeks thereafter. Morning serum cortisol (8.00-10.00 a.m.) was measured at the start and at the end of the treatment period. Adverse events were recorded throughout the total study period. Significant improvements over baseline were reported in both groups in terms of lung function, symptoms and use of rescue inhaled salbutamol. Equivalence between groups was demonstrated for the primary end-point morning PEFR, as well as for evening PEFR and FEV1. No statistically significant differences in the comparisons between groups, except for FEF25 (P=0.044), were observed in any of the other efficacy variables. Adverse events were reported in 31% of patients in the BDP-HFA group and in 32% in the CFC group. Adverse drug reactions were 4 and 2 in the two groups, respectively. No drug-related serious adverse events were reported in either of the groups. No signs of relevant adrenal suppression were observed in both groups: 2 patients in each group had final values below the normal range. In conclusion, the BDP-HFA-134a formulation proved to be equivalent in efficacy and comparable in safety to the standard BDP-CFC product over 12 weeks in adult patients with mild-to-moderate persistent asthma.


Assuntos
Propelentes de Aerossol , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Beclometasona/administração & dosagem , Hidrocarbonetos Fluorados , Administração por Inalação , Adolescente , Adulto , Aerossóis , Idoso , Asma/fisiopatologia , Clorofluorcarbonetos , Método Duplo-Cego , Feminino , Glucocorticoides/administração & dosagem , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Pico do Fluxo Expiratório , Mecânica Respiratória/efeitos dos fármacos , Resultado do Tratamento
7.
Pneumonol Alergol Pol ; 68(3-4): 109-19, 2000.
Artigo em Polonês | MEDLINE | ID: mdl-11004845

RESUMO

The aim of this study was to determine and to evaluate silica induced lung cell reactivity--if any--in bronchoalveolar space, before clinical changes develop. Bronchoalveolar lavage (BAL) was carried out in 15 nonsmoking individuals with chronic professional silica exposure, free of lung signs and symptoms. Controls were healthy nonsmokers. Routine BAL cytology (HE, MGG) was completed by mast cell staining (toluidine blue). BAL lymphocyte subsets were phenotyped by direct two- and three-color immunofluorescence (applied DAKO A/S monoclonal antibodies: anti-CD3, CD4, CD8, CD11b, CD14, CD15, CD16 + 56, CD19, CD25, CD45, HLA-DR). Parallel staining was performed in peripheral blood. In individuals with chronic silica exposure we found: significant increase in alveolar macrophage (362 +/- 45 vs 160 +/- 33 x 10(3) cells/ml, p < 0.05), lymphocyte (61 +/- 9 vs 24 +/- 5 x 10(3) cells/ml, p < 0.05) and BAL total cell (415 +/- 76 vs 187 +/- 34 x 10(3) cells/ml, p < 0.05) numbers; significant increase in mast cell (0.4 +/- 0.1 vs 0.2 +/- 0.1, p < 0.05), NK cell (7.0 +/- 1.8 vs 3.6 +/- 1.0, p < 0.05) and Th early activated lymphocyte percent (CD4 + CD25+ calculated as percentage of CD4+ cells: 15.1 +/- 1.5 vs 7.8 +/- 1.6, p < 0.01). All results were presented as median +/- SEM. Bronchoalveolar space of people with chronic silica exposure usually shows pathological reaction (especially macrophagic alveolitis), although they are free of manifested pulmonary disease. Th early activated lymphocytes, NK cells and mast cells seem to play important role in the early interstitial lung tissue reaction to silica.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Monitoramento Ambiental , Exposição Ocupacional/efeitos adversos , Dióxido de Silício/efeitos adversos , Adolescente , Adulto , Idoso , Antígenos CD/análise , Contagem de Células , Poeira/efeitos adversos , Feminino , Imunofluorescência , Humanos , Contagem de Linfócitos , Subpopulações de Linfócitos , Macrófagos Alveolares/patologia , Masculino , Mastócitos/patologia , Pessoa de Meia-Idade
9.
Pneumonol Alergol Pol ; 66(5-6): 321-9, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-9857653

RESUMO

The analysis of mast cells in bronchoalveolar lavage (BAL) is rarely performed in routine diagnostic protocol. The BAL mast cells are rather difficult to be identified due to their paucity and technical problems with fixation and staining methods. The present study was carried out in order to characterize quantitatively and morphologically of mast cells obtained in bronchoalveolar lavage from 38 patients with several lung disorders. The percentage of mast cells ranged from: 0.0-0.6% (aspirin intolerant asthmatics), 0.1-1.8% (aspirin tolerant asthmatics), 0.9-1.8% (sarcoidosis), 1.5-2.0% (fibrosis), 0.04-0.08% (normals). There were statistically significant differences in the mast cells count between tested disease groups. Lung mast cells exhibited heterogeneity of size, shape, intensity of staining and degree of degranulation. Bronchoalveolar lavage is a very interesting and suitable model for the study of human lung mast cells. These cells should be analysed because of their clinical importance in pathogenesis of several lung disorders. We recommend, Carnoy's solution as a fixative and 0.5% solution of Toluidine blue (pH-0.5 with prolongation of staining time to 5-7 days at 4 degrees C) as a dye for routine diagnostic method of BAL mast cells identification.


Assuntos
Asma/diagnóstico , Líquido da Lavagem Broncoalveolar/citologia , Doenças Pulmonares Intersticiais/diagnóstico , Mastócitos/patologia , Contagem de Células , Diagnóstico Diferencial , Humanos , Fibrose Pulmonar/diagnóstico , Sarcoidose/diagnóstico
10.
J Clin Invest ; 101(4): 834-46, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9466979

RESUMO

Aspirin causes bronchoconstriction in aspirin-intolerant asthma (AIA) patients by triggering cysteinyl-leukotriene (cys-LT) production, probably by removing PGE2-dependent inhibition. To investigate why aspirin does not cause bronchoconstriction in all individuals, we immunostained enzymes of the leukotriene and prostanoid pathways in bronchial biopsies from AIA patients, aspirin-tolerant asthma (ATA) patients, and normal (N) subjects. Counts of cells expressing the terminal enzyme for cys-LT synthesis, LTC4 synthase, were fivefold higher in AIA biopsies (11.5+/-2.2 cells/mm2, n = 10) than in ATA biopsies (2.2+/-0.7, n = 10; P = 0. 0006) and 18-fold higher than in N biopsies (0.6+/-0.4, n = 9; P = 0. 0002). Immunostaining for 5-lipoxygenase, its activating protein (FLAP), LTA4 hydrolase, cyclooxygenase (COX)-1, and COX-2 did not differ. Enhanced baseline cys-LT levels in bronchoalveolar lavage (BAL) fluid of AIA patients correlated uniquely with bronchial counts of LTC4 synthase+ cells (rho = 0.83, P = 0.01). Lysine-aspirin challenge released additional cys-LTs into BAL fluid in AIA patients (200+/-120 pg/ml, n = 8) but not in ATA patients (0. 7+/-5.1, n = 5; P = 0.007). Bronchial responsiveness to lysine-aspirin correlated exclusively with LTC4 synthase+ cell counts (rho = -0.63, P = 0.049, n = 10). Aspirin may remove PGE2-dependent suppression in all subjects, but only in AIA patients does increased bronchial expression of LTC4 synthase allow marked overproduction of cys-LTs leading to bronchoconstriction.


Assuntos
Aspirina/efeitos adversos , Asma/enzimologia , Brônquios/enzimologia , Glutationa Transferase/biossíntese , Asma/induzido quimicamente , Asma/imunologia , Asma/patologia , Biópsia , Brônquios/patologia , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/biossíntese , Eosinófilos/imunologia , Feminino , Humanos , Contagem de Leucócitos , Leucotrienos/biossíntese , Masculino , Placebos/farmacologia , Linfócitos T/imunologia
12.
Mediators Inflamm ; 6(1): 53-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18472834

RESUMO

Luminol-enhanced chemiluminescence was measured in fresh whole human blood, or human neutrophils isolated from heparinized blood, human alveolar macrophages and rat alveolar macrophages stimulated with bacterial endotoxin (LPS). Tetraacetate esters of rooperol, a dicatechol showing anticytokine activity, added to cells simultaneously with LPS inhibited the respiratory burst. The effective concentrations of rooperol were in the range of 1-10 muM depending on cell type and corresponded well with inhibition of nitric oxide production by rat alveolar macrophages. Thus rooperol may reduce some effects of excessive phagocytic activity and inflammatory reaction but by quenching free radicals production may also diminish the resistance to bacterial infections.

13.
Am J Respir Crit Care Med ; 154(6 Pt 1): 1608-14, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8970343

RESUMO

We have shown that inhalation of lysine aspirin enhances leukotriene production in the lungs of patients with aspirin-induced asthma (AIA). To assess the specificity of this reaction, we compared two well-matched groups of patients: eleven with AIA versus 14 asthmatics tolerant to aspirin (ATA). All subjects underwent bronchoalveolar lavage (BAL) with saline followed immediately by instillation of 10 mg of lysine aspirin, into a right middle lobe segmental bronchus, which was lavaged 15 min later. At baseline the two groups did not differ with respect to BAL fluid concentrations of cyclooxygenase products, peptido-leukotrienes, histamine, tryptase, interleukin-5 (IL-5), eosinophil cationic protein (ECP), or eosinophil number. Fifteen minutes after aspirin instillation, there was a statistically significant rise in peptido-leukotrienes, IL-5, and eosinophil number in AIA, but not in ATA, but not in ATA patients. In the former, but not in the latter group, mean histamine concentrations rose in response to aspirin, approaching the level of statistical significance. Tryptase and ECP levels showed no significant change. Aspirin significantly depressed PGE2 and thromboxane B2 (TXB2) in both groups, however PGD2, PGF2 alpha, and 9 alpha, 11 beta-PGF2 decreased only in ATA patients. A characteristic disturbance in eicosanoid balance, produced by aspirin in patients intolerant to this drug, might explain precipitation of asthma attacks.


Assuntos
Aspirina/efeitos adversos , Asma/induzido quimicamente , Asma/metabolismo , Brônquios/efeitos dos fármacos , Eicosanoides/biossíntese , Pulmão/metabolismo , Ribonucleases , Adulto , Araquidonato 5-Lipoxigenase/metabolismo , Proteínas Sanguíneas/metabolismo , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Quimases , Proteínas Granulares de Eosinófilos , Eosinófilos , Feminino , Histamina/metabolismo , Humanos , Interleucina-5/metabolismo , Contagem de Leucócitos , Leucotrienos/metabolismo , Masculino , Pessoa de Meia-Idade , Prostaglandina-Endoperóxido Sintases/metabolismo , Prostaglandinas/metabolismo , Serina Endopeptidases/metabolismo , Triptases
15.
Eur Respir J ; 8(7): 1091-9, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7589392

RESUMO

The treatment of chronic severe asthma is unsatisfactory for many patients. The aim of the study was to determine the effects of treatment of steroid-dependent asthma with cyclosporin. We performed a double-blind, placebo-controlled, randomized, parallel group trial on the effect of cyclosporin on pulmonary function, asthma severity and tapering of prednisone in 34 steroid-dependent asthmatics (mean oral prednisone dose: 16 mg.day-1). The study consisted of: 1) baseline period (12 weeks); 2) experimental period divided into two parts: Part I (12 weeks) cyclosporin or placebo treatment; Part II (22 weeks) cyclosporin or placebo treatment and oral prednisone reduction; and 3) follow-up observation (8 weeks). Asthma symptoms score, pulmonary function tests (daily peak expiratory flow (PEF) and bi-weekly forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and maximal mid-expiratory flow (MEF50), biochemical profile and blood cyclosporin levels were monitored throughout the study. Following cyclosporin administration, a slight beneficial effect on some subjective parameters of asthma severity was observed. At the same time, no beneficial effect on pulmonary function was noted. The time trends analysis of mean daily prednisone doses between the treatment groups revealed a statistically significant difference indicating that, during prednisone reduction, cyclosporin seemed to be slightly more efficient than placebo in reducing the requirement for systemic corticosteroid, even though the steroid reduction was accompanied by slight impairment of some pulmonary function. However, there was no significant difference in the final dose reduction between the treatment groups. These data and the known toxicity of the drug suggest a limited place for cyclosporin treatment in steroid-dependent bronchial asthma.


Assuntos
Asma/tratamento farmacológico , Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Adulto , Antiasmáticos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Prednisona/administração & dosagem , Testes de Função Respiratória , Fatores de Tempo
16.
Am J Respir Crit Care Med ; 149(4 Pt 1): 940-6, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8143059

RESUMO

We have recently shown that oral aspirin provocation leads to an increase in LTE4 and a reduction in 11-dehydro-TXB2 levels in urine of patients with aspirin induced-asthma (AIA). To test the hypothesis that cyclooxygenase inhibition and an enhancement of cysteinyl-leukotriene production occurs in the lungs of patients with AIA, we examined the eicosanoid levels in bronchoalveolar lavage fluid obtained 30 min after lysine-aspirin or placebo inhalation in 10 patients with AIA. Eosinophil cationic protein (ECP) levels were determined to evaluate eosinophil activation. Six asthmatics nonsensitive to aspirin (NA) underwent challenge with placebo. The dose of lysine-aspirin inhaled by patients with AIA was equal to that which had produced > or = 20% fall in FEV1. Compared with NA, patients with AIA had: (1) eicosanoid levels, particularly PGE2 and TXB2, elevated and (2) higher number of eosinophils and ECP. The overproduction of eicosanoids could be related to a distinct eosinophilic inflammation in airways of patients with AIA. Inhalation of lysine-aspirin had no effects on 12-HETE and 15-HETE levels, but it markedly depressed cyclooxygenase products and significantly enhanced leukotriene production in the lungs of patients with AIA.


Assuntos
Aspirina/análogos & derivados , Aspirina/efeitos adversos , Asma/metabolismo , Líquido da Lavagem Broncoalveolar/química , Eicosanoides/análise , Lisina/análogos & derivados , Adulto , Asma/induzido quimicamente , Testes de Provocação Brônquica/métodos , Testes de Provocação Brônquica/estatística & dados numéricos , Broncoscopia , Tolerância a Medicamentos , Feminino , Tecnologia de Fibra Óptica , Humanos , Masculino , Pessoa de Meia-Idade
17.
Eur Respir J ; 6(3): 391-9, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8386106

RESUMO

In order to examine the hypothesis that in aspirin-induced asthma (AIA) cyclooxygenase inhibition is associated with enhanced release of leukotrienes (LTs), we measured urinary leukotriene E4 (LTE4) and 11-dehydro-thromboxane B2 (TXB2) (as a measure of cyclooxygenase production) following challenge with oral aspirin or inhaled methacholine, in 10 AIA patients. We also determined serum tryptase and eosinophilic catonic protein (ECP) levels, in order to evaluate mast cell and eosinophil activation. Urinary LTE4 excretion was increased sevenfold 4-6 h after aspirin challenge, while 11-dehydro-TXB2 decreased gradually reaching 50% baseline levels 24 h after challenge (p < 0.05). This was accompanied by a significant fall in blood eosinophil count at 6 h, and a tendency to a rise in ECP. The intensity of both LTE4 and 11-dehydro-TXB2 responses depended on the dose of aspirin used (p < 0.001, analysis of variance (ANOVA)). The accompanying maximum fall in forced expiratory volume in one second (FEV1) was not correlated with peak LTE4 levels. In contrast to aspirin, methacholine challenge producing comparable bronchial obstruction, did not alter eicosanoid excretion or serum tryptase or ECP levels. In a separate study, lysine-aspirin inhalation challenge was performed in seven AIA patients, four of whom had responded with a rise in serum tryptase to oral aspirin challenge. Challenge with inhaled aspirin led to similar bronchoconstriction as with oral challenge, but non-respiratory symptoms such as scarlet flush or rhinorrhea were absent, and serum tryptase levels remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aspirina/efeitos adversos , Asma/induzido quimicamente , Broncoconstrição/efeitos dos fármacos , Mastócitos/imunologia , Ribonucleases , SRS-A/análogos & derivados , Tromboxano B2/análogos & derivados , Adulto , Asma/imunologia , Asma/metabolismo , Proteínas Sanguíneas/análise , Testes de Provocação Brônquica , Quimases , Proteínas Granulares de Eosinófilos , Eosinófilos/imunologia , Feminino , Humanos , Leucotrieno E4 , Masculino , Cloreto de Metacolina , Pessoa de Meia-Idade , SRS-A/urina , Serina Endopeptidases/sangue , Tromboxano B2/urina , Triptases
18.
Lancet ; 339(8797): 873, 1992 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-1347883
19.
J Lab Clin Med ; 119(1): 48-51, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1309376

RESUMO

The etiology of aspirin-sensitive asthma is unknown, but a plausible hypothesis is that the inhibitory effect of aspirin on the cyclooxygenase enzyme increases formation of bronchoconstrictor leukotrienes via "shunting" of unmetabolized arachidonic acid into metabolism by the 5-lipoxygenase enzyme. The severity and rapidity of bronchospasm that is induced by cyclooxygenase-inhibiting drugs in aspirin-sensitive asthmatics is directly related to the dose and to the potency of the drug to inhibit the cyclooxygenase enzyme. Since increased leukotriene synthesis has recently been shown to occur during allergen-induced asthma, we have examined whether altered leukotriene synthesis correlates with the degree of either cyclooxygenase inhibition or bronchospasm during asthma that is induced by doses of aspirin that range from 30 to 365 mg in individual patients. Excretion of leukotriene E4 was increased by a mean of 361% +/- 76% (p less than 0.05) during aspirin-induced asthma episodes, but the degree of increase for individual patients did not correlate with the degree of bronchospasm or inhibition of platelet thromboxane B2 formation. Thus although the endogenous synthesis of potent bronchoconstrictor leukotrienes increases during aspirin-induced bronchospasm, it appears unlikely that a direct "shunting" of unmetabolized arachidonate into leukotriene synthesis represents the mechanism of aspirin-induced asthma.


Assuntos
Aspirina , Asma/induzido quimicamente , SRS-A/análogos & derivados , Asma/urina , Creatinina/urina , Relação Dose-Resposta a Droga , Humanos , Leucotrieno E4 , SRS-A/urina
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