摘要:

ABSTRACTAn apparatus to generate solid particles was tested for use in diagnosing occupational asthma. This equipment measures the inhaled dose of dry particles during specific inhalation challenge. It includes an aerosol generator, a cyclone type particle size selector, and an inhalation chamber to which a patient breathing at tidal volume can be connected for the test. It is fully controlled by a standard personal computer in automatic mode, acting on the flow rate and the aerosol generator to maintain the concentration at a fixed value, usually 3 mg/m3. The dose of aerosol delivered to the patient was calculated from the aerosol concentration, and the inhaled volume was calculated by integration of the corresponding signals. The coefficient of variation for this measurement was estimated to be 12%. The mass median aerodynamic diameter (MMAD) of aerosol inside the inhalation chamber was measured for three substances: lactose, wheat flour, and buckwheat flour. The MMAD of the aerosol inside the chamber was also estimated from the particle size distribution of the raw powder. The relative difference between the measured MMAD and the calculated value was less than 15%. The corresponding relative difference between the measured geometrical SD and the calculated value was found to be less than 26%.

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.1

年代:2000

数据来源: MAL

摘要:

ABSTRACTThe aims of this study were to (1) quantify the particle size characteristics of several antibiotics considered suitable for aerosol therapy after aerosolization with the PARI IS/2 nebulizer (Pari GmbH, Sarnberg, Germany) and (2) determine the degree to whichin vitroantimicrobial activity of these antibiotics is maintained after nebulization. The aerosolized drugs were tobramycin sulfate, streptomycin, and imipenem, with saline solution as the control. Mean mass aerodynamic diameter of the nebulized drugs was 3.25 μm for tobramycin, 2.26 μm for imipenem, and 2.38 μm for streptomycin.In vitrotests showed that tobramycin and imipenem were unaltered in their bacteriostatic activity against strains ofEscherichia coli(American Type Culture Collection [ATCC] 25922) andStaphylococcus aureus(ATCC 29213) as well as againstPseudomonas aeruginosa(ATCC 27853) with minimal inhibitory concentration (MIC) values less than 0.3 μg/mL. Nebulized streptomycin showed significantly higher MIC values againstP. aeruginosa(ATCC 27853). These results suggest that tobramycin and imipenem may be prescribed as an aerosol generated by jet nebulization (PARI IS/2) to treatS. aureus, E. coli,andP. aeruginosainfections without any risk of altering the drugs1minimum bacteriostatic activity by the nebulization process. Aerosolization of streptomycin with this nebulizer may not be as effective againstP. aeruginosabecause it seems to alter the bacteriostatic activ

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.11

年代:2000

数据来源: MAL

摘要:

ABSTRACTThe objective of this study was to examine the effects of nasal passage characteristics on anterior particle deposition during cyclical breathing. Forty healthy, nonsmoking, adult subjects participated in this study. Nasal passage characteristics such as nostril length, width, angle, ellipticity, and minimum nasal cross-sectional area were measured. The subjects inhaled a polydisperse radioactively tagged aerosol (mass median aerodynamic diameter = 5.4 μm, geometric standard deviation [GSD] = 1.3) into the nose and exhaled through the mouth. The amount of radioactivity in the nose was measured immediately after inhalation and thereafter for 54 minutes. At 52.5 minutes, subjects wiped the accessible portion of the anterior nose to remove any remaining activity. The difference in activity at 52 and 54 minutes was used as a measure of activity removed during the nose wipe. Percentage of activity in the nasal passage at 52 minutes and percentage of activity removed with the nose wipe were considered surrogates for particles deposited in the anterior nasal passage. A multiple regression analysis showed that the degree of ellipticity of the nostrils was significantly related to particle deposition in the anterior nasal passage. These results suggest that ellipticity of the nostrils may be a determinant of the amount of particle deposition in the anterior nasal passage

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.17

年代:2000

数据来源: MAL

摘要:

ABSTRACTThe aim of this study was to compare the immediate and long-term bronchodilator effect as well as the patient acceptability of a 2-week, multidrug, inhalation treatment delivered by a metered dose inhaler (MDI) versus a jet nebulizer in a group of elderly patients with chronic obstructive pulmonary disease (COPD) or asthma and an at least partially reversible airflow obstruction. Twenty elderly outpatients (17 men; mean ± SD age, 67 ± 2 years; mean ± SD baseline forced expiratory volume in 1 second [FEV1], 46.5 ± 14% of predicted value) with COPD or asthma participated in the study, which was of an open, randomized, crossover design. After a 1-day baseline evaluation, including patient history, clinical examination, and spirometry, participants were randomly assigned to receive a multidrug inhalation treatment (a combination of salbutamol, ipratropium, and flunisolide) with either an MDI or a jet nebulizer. Two weeks later, they were shifted to treatment with the alternative system for a further 2 weeks. FEV1was measured on the first and fourteenth days of each treatment period, on each occasion both before and 30 minutes after the morning inhalation. At the end of the study, patients were asked to express a personal preference for one of the two inhalation treatments with regard to effectiveness and acceptability by filling out a simple questionnaire. Both the MDI and jet nebulizer had a significant immediate bronchodilator effect on the first and fourteenth days of treatment, with no differences between treatments. No long-term bronchodilator effect was seen with either aerosol delivery system. Patient preferences were clearly in favor of the jet nebulizer with regard to effectiveness and in favor of the MDI with regard to acceptability. In conclusion, in elderly patients with COPD or asthma and partially reversible airflow obstruction, a maintenance multidrug bronchodilator/anti-inflammatory inhalation treatment produced a statistically significant and clinically relevant bronchodilator effect without substantial differences between the two delivery systems. Most patients considered the MDI to be more acceptable and the jet nebulizer to be more effective. These preferences should be taken into consideration when prescribing a maintenance aerosol inhalation treatm

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.25

年代:2000

数据来源: MAL

摘要:

ABSTRACTSeventy-two children (mean age, 10.1 years) with stable moderate asthma who completed a 7-day run-in period were randomized to receive a 4-week treatment with beclomethasone dipropionate (200 μg twice daily) administered through two different powder inhalers (Pulvinal; Chiesi Farmaceutici S.p.A, Parma, Italy and Diskhaler; Glaxo-Wellcome, Evreux, France) in a parallel group design. Sixty-nine patients completed the study. Morning and evening peak expiratory flow values, the use of rescue salbutamol, and the severity of clinical symptoms were recorded daily on a diary card. Pulmonary function tests were performed at baseline and then after 2 and 4 weeks of treatment. Pulmonary function values, daily morning and evening peak expiratory flow, and most of the clinical symptoms significantly improved, although the use of rescue salbutamol significantly decreased from the second week of treatment until the end of the study in both groups. Equivalence of efficacy between groups was demonstrated for both pulmonary function and clinical parameters. We conclude that the Pulvinal inhaler is as efficacious as the Diskhaler in beclomethasone-based therapy of asthmatic children

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.35

年代:2000

数据来源: MAL

摘要:

ABSTRACTThe significance of aerosols in medicine is increased when the distribution of inhaled aerosols in the different respiratory tract compartments and their interaction with lung structures are known. The aim of this study was to investigate the retention of the hydrophobic Teflon spheres used in human beings so as to analyze their regional distribution and to study their interaction with lung structures at the deposition site. Six intubated and anesthetized Syrian Golden hamsters inhaled aerosols of Teflon particles with an aerodynamic diameter of 5.5 μm by continuous negative-pressure ventilation adjusted to slow breathing. Lungs were fixed by intravascular perfusion within 21 minutes after inhalation was started, and tissue samples were taken and processed for light and electron microscopy. The stereological (fractionator) analysis revealed that particle retention was the greatest in alveoli (72.4%), less in intrapulmonary conducting airways (22.9%), and the least in extrapulmonary mainstem bronchi (0.3%) and trachea (4.4%). Particles were found submerged in the aqueous lining layer and in close vicinity to epithelial cells. In intrapulmonary conducting airways, 21.5% of Teflon particles had been phagocytized by macrophages. This study with highly hydrophobic Teflon particles clearly demonstrates that for spheres of this size, surface tension and line tension forces rather than the particles' surface free energy are decisive for the displacement of particles into the aqueous phase by surfactant. It was this displacement that enabled subsequent interaction with macrophages. Refined knowledge of particle retention may help us to better understand the biological response to inhaled particles

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.43

年代:2000

数据来源: MAL

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.57

年代:2000

数据来源: MAL

ISSN:0894-2684    

DOI:10.1089/jam.2000.13.59

年代:2000

数据来源: MAL