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OBJECTIVES: To determine whether, in stable patients with chronic obstructive pulmonary disease, administration of theophylline in combination with short-acting or long-acting inhaled beta2-agonists is more efficacious than is a placebo or each of these drugs used in isolation. METHODS: A systematic review and meta-analysis were carried out. All randomized and double-blind clinical trials found in the literature were selected. RESULTS: A total of eight studies were included. In comparing the effect of theophylline combined with beta2-agonists to that of a placebo, we found a statistically significant improvement in mean FEV1 (0.27 L; 95% CI: 0.11 to 0.43) and mean dyspnea (-0.78; 95% CI: -1.26 to -0.29). None of the meta-analyses performed detected any difference between the results obtained using theophylline combined with beta2-agonists and those obtained using beta2-agonists alone. When the administration of theophylline combined with beta2-agonists was compared to that of theophylline alone, there was a statistically significant improvement in mean dyspnea (-0.19; 95% CI: -0.34 to 0.04). CONCLUSION: In patients with stable chronic obstructive pulmonary disease, theophylline combined with beta2 agonists is more efficacious than is a placebo in terms of improving FEV1 and dyspnea. In addition, theophylline combined with beta2 agonists is more efficacious than is theophylline in improving dyspnea. Furthermore, administration of theophylline combined with beta2 agonists is no more efficacious, for any of the variables studied, than is the use of beta2-agonists in isolation.

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OBJETIVOS: Avaliar se o tratamento com teofilina associada ao beta2-agonista inalatório de curta ou longa duração é mais eficaz que o placebo e que o uso isolado de cada um dos fármacos, para os pacientes com doença pulmonar obstrutiva crônica estável. MÉTODOS: Realizou-se uma revisão sistemática com metanálise, sendo selecionados todos os ensaios clínicos aleatórios e duplo-cegos encontrados na literatura. RESULTADOS: Foram incluídos oito estudos. Teofilina associada ao beta2-agonista vs. placebo: houve melhora estatisticamente significante para o VEF1 (L), com média 0,27 (IC95 por cento 0,11 a 0,43); e para a dispnéia, com média -0,78 (IC95 por cento -1,26 a -0,29). Teofilina associada ao beta2-agonista vs. beta2-agonista isolado: nenhuma das metanálises realizadas detectou diferença entre os grupos. Teofilina associada ao beta2-agonista vs. teofilina isolada: houve melhora estatisticamente significante para a dispnéia, com média -0,19 (IC95 por cento -0,34 a -0,04). CONCLUSÕES: Em pacientes com doença pulmonar obstrutiva crônica estável: 1) teofilina associada ao beta2-agonista é mais eficaz que o placebo, em relação ao VEF1 e dispnéia; 2a) teofilina associada ao beta2-agonista é mais eficaz que a teofilina isolada, em relação à dispnéia; e 2b) teofilina associada ao beta2-agonista não é mais eficaz que o beta2-agonista isolado, para quaisquer das variáveis estudadas.

OBJECTIVES: To determine whether, in stable patients with chronic obstructive pulmonary disease, administration of theophylline in combination with short-acting or long-acting inhaled beta2-agonists is more efficacious than is a placebo or each of these drugs used in isolation. METHODS: A systematic review and meta-analysis were carried out. All randomized and double-blind clinical trials found in the literature were selected. RESULTS: A total of eight studies were included. In comparing the effect of theophylline combined with beta2-agonists to that of a placebo, we found a statistically significant improvement in mean FEV1 (0.27 L; 95 percentCI: 0.11 to 0.43) and mean dyspnea (-0.78; 95 percentCI: -1.26 to -0.29). None of the meta-analyses performed detected any difference between the results obtained using theophylline combined with beta2-agonists and those obtained using beta2-agonists alone. When the administration of theophylline combined with beta2-agonists was compared to that of theophylline alone, there was a statistically significant improvement in mean dyspnea (-0.19; 95 percentCI: -0.34 to 0.04). CONCLUSION: In patients with stable chronic obstructive pulmonary disease, theophylline combined with beta2 agonists is more efficacious than is a placebo in terms of improving FEV1 and dyspnea. In addition, theophylline combined with beta2 agonists is more efficacious than is theophylline in improving dyspnea. Furthermore, administration of theophylline combined with beta2 agonists is no more efficacious, for any of the variables studied, than is the use of beta2-agonists in isolation.

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The aim of this study was to study the convective drying of the hydroalcoholic extracts obtained from powdered guarana seeds in a spouted bed dryer. The influence of process variables, such as the convective airflow rate, extract feed rate, and air inlet temperature, on the quality of the dry extract was determined using the caffeine and moisture content for the process evaluation. The caffeine content in the alcoholic and dried extracts was determined by capillary gas chromatography. The experiments were performed following a 3(3) factorial design and the data analyzed by response surface. The analysis of dry extract showed that the air and extract feed rates did not significantly affect (25% level) the caffeine content, but that drying temperature is a major factor to consider when the extract is submitted to fluid bed drying. Caffeine losses were significant (1% level) for drying temperatures above 120 degrees C, while moisture content was lower than 3% for temperatures above 120 degrees C. The data showed that there is an optimum temperature for the drying of guarana extracts in spouted beds, and under the conditions used in this study it was 120 degrees C.

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Experimental data for the supercritical CO(2) extraction of purine alkaloids (caffeine, theobromine, and theophylline) from ground herbal maté tea (Ilex paraguaryensis) using a high-pressure apparatus are presented. Caffeine, theophylline, and theobromine were identified in the extracted fractions using HPLC. Results indicated a much higher CO(2) selectivity for caffeine in comparison with those for theophylline and theobromine. Solubilities of pure compounds in carbon dioxide were also determined at 313.2, 323.2, 338.2, and 343.2 K, and pressures ranging from 14 to 24 MPa. Caffeine solubility exhibited a retrograde behavior with temperature while theophylline and theobromine manifested a normal behavior at conditions explored in this study. Solubilities in binary CO(2)/purine alkaloid model systems were much higher than those obtained during extraction of maté tea, demonstrating the difficulty of using binary data in predicting complex multicomponent behavior.

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