In this study, three different molecules (cholesterol, phosphatidic acid, and polyethylene glycol) were used for the stabilization of liposomes during the nebulization process. The purpose of this article is to answer the question of whether the change in the composition of liposomes affected the parameters of generated aerosol and whether the nebulization process affected observed properties of liposomes. Firstly, liposomes with different composition were prepared and their properties were checked by dynamic and electrophoretic light scattering. The membrane properties were measured by fluorescence spectroscopy - especially generalized polarization (Laurdan) and anisotropy (Diphenylhexatriene). The same characteristic of liposomes was measured after the nebulization by vibrating mesh nebulizer. Cholesterol was capable of liposome stabilization because of increased membrane fluidity. The membrane properties of the outer and inner parts were not influenced by the nebulization process. Electrostatic stabilization was successful for the lowest concentration of phosphatidic acid, but after the nebulization process the hydration of the membrane outer part was changed. Higher amount of PEG needs to be added for successful steric stabilization. The nebulization process of the two lowest concentrations of PEG slightly influenced immobilized water and the rigidity of inner part of the membrane (especially around the phase transition temperature).

• MeSH
• aerosoly MeSH
• chirurgické síťky * MeSH
• liposomy * MeSH
• nebulizátory a vaporizátory MeSH
• velikost částic MeSH
• Publikační typ
• časopisecké články MeSH

Nebulization with saline solution, although commonly used to alleviate respiratory symptoms, particularly in children, is often questioned concerning its effectiveness. In this study, we investigated the effects of isotonic saline nebulization on lung function in 40 children (mean age of 14±1 years) suffering from different types of airway disorders. Measurements were carried out directly before and up to 15 min after nebulization, for six days in a row, always on the same day time in the morning. The children were divided into two study groups according to the baseline ratio of forced expired volume in one second/forced vital capacity (FEV1/FVC), below and above 80 %. We found significant improvements after saline nebulization in FEV1, mid-expiratory flow at 50 % and 75 % of FVC (MEF50 and MEF75), and peak expiratory flow (PEF) in the group with the baseline FEV1/FVC less than 80 %. In contradistinction, children with an index greater than 80 % displayed no appreciable changes in the lung function variables when compared with the baseline level before saline nebulization. We conclude that isotonic saline nebulization might mitigate the functional signs of threatening pulmonary obstruction and as such may be clinically useful in pediatric patients with mild respiratory problems.

• MeSH
• lidé MeSH
• mechanika dýchání účinky léků   fyziologie   MeSH
• mladiství MeSH
• nebulizátory a vaporizátory * MeSH
• plíce účinky léků   fyziologie   MeSH
• poruchy dýchání diagnóza   patofyziologie   MeSH
• respirační funkční testy metody   MeSH
• solný roztok aplikace a dávkování   MeSH
• usilovný výdechový objem účinky léků   fyziologie   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Liposomal carrier systems have emerged as a promising technology for pulmonary drug delivery. This study focuses on two selected liposomal systems, namely, dipalmitoylphosphatidylcholine stabilized by phosphatidic acid and cholesterol (DPPC-PA-Chol) and dipalmitoylphosphatidylcholine stabilized by polyethylene glycol and cholesterol (DPPC-PEG-Chol). First, the research investigates the stability of these liposomal systems during the atomization process using different kinds of nebulizers (air-jet, vibrating mesh, and ultrasonic). The study further explores the aerodynamic particle size distribution of the aerosol generated by the nebulizers. The nebulizer that demonstrated optimal stability and particle size was selected for more detailed investigation, including Andersen cascade impactor measurements, an assessment of the influence of flow rate and breathing profiles on aerosol particle size, and an in vitro deposition study on a realistic replica of the upper airways. The most suitable combination of a nebulizer and liposomal system was DPPC-PA-Chol nebulized by a Pari LC Sprint Star in terms of stability and particle size. The influence of the inspiration flow rate on the particle size was not very strong but was not negligible either (decrease of Dv50 by 1.34 μm with the flow rate increase from 8 to 60 L/min). A similar effect was observed for realistic transient inhalation. According to the in vitro deposition measurement, approximately 90% and 70% of the aerosol penetrated downstream of the trachea using the stationary flow rate and the realistic breathing profile, respectively. These data provide an image of the potential applicability of liposomal carrier systems for nebulizer therapy. Regional lung drug deposition is patient-specific; therefore, deposition results might vary for different airway geometries. However, deposition measurement with realistic boundary conditions (airway geometry, breathing profile) brings a more realistic image of the drug delivery by the selected technology. Our results show how much data from cascade impactor testing or estimates from the fine fraction concept differ from those of a more realistic case.

• MeSH
• 1,2-dipalmitoylfosfatidylcholin MeSH
• aerosoly MeSH
• aplikace inhalační MeSH
• bronchodilatancia * MeSH
• cholesterol MeSH
• design vybavení MeSH
• lékové transportní systémy MeSH
• lidé MeSH
• liposomy MeSH
• nebulizátory a vaporizátory MeSH
• trachea * MeSH
• velikost částic MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• referenční standardy MeSH
• selen krev   MeSH
• senzitivita a specificita MeSH
• spektrální analýza metody   MeSH

A microfabricated pneumatic electrospray nebulizer has been developed and evaluated using computer simulations and experimental measurements of the MS signals. The microdevice under development is designed for electrospray MS interfacing without the need to fabricate an electrospray needle and can be used as a disposable or an integral part of a reusable system. The design of the chip layout was supported by computational fluid dynamics simulations. The tested microdevices were fabricated in glass using conventional photolithography, followed by wet chemical etching and thermal bonding. The performance of the microfabricated nebulizer was evaluated by means of TOF-MS with a peptide mixture. It was demonstrated that the nebulizer, operating at supersonic speed of the nebulizing gas, produced very stable nanospray (900 nL/min) as documented by less than 0.1% (SE) fluctuation in total mass spectrometric signal intensity.

• MeSH
• design s pomocí počítače * MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací metody   MeSH
• mikrofluidní analytické techniky přístrojové vybavení   MeSH
• nebulizátory a vaporizátory * MeSH
• počítačová simulace * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Kazuistika popisuje nečekané problémy ve správné inhalační technice během aplikace bronchodilatační inhalace z domácího nebulizátoru u pacientky v seniorském věku s astmatem.

Unexpected problems with correct inhalation technique during home bronchodilator nebulization of patient in senior age with asthma are described in our case history.

• MeSH
• adherence pacienta * MeSH
• albuterol farmakologie   terapeutické užití   MeSH
• aplikace inhalační MeSH
• bronchiální astma * farmakoterapie   terapie   MeSH
• bronchodilatancia farmakologie   terapeutické užití   MeSH
• diagnostické techniky dýchacího ústrojí MeSH
• ipratropium farmakologie   terapeutické užití   MeSH
• lidé MeSH
• nebulizátory a vaporizátory * využití   MeSH
• odmítnutí terapie pacientem * MeSH
• progrese nemoci MeSH
• senioři MeSH
• vzdělávání pacientů jako téma * MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

To explore the use of oscillometry as a measure of airway responsiveness, 69 asthmatic children underwent histamine and methacholine bronchoprovocation using dosimeter-MedicAid (Jaeger Co.; Germany) and DeVilbiss nebulizers (DeVilbiss, Bornemouth; England). The mean increase in R5 resistance in challenge testing measured after methacholine with the dosimeter-MedicAid nebulizer was 77.14% compared with 65.05% using histamine. Using the dosimeter-DeVilbiss nebulizer, the mean increases in R5 resistance following methacholine and histamine testing were 57.50% and 59.36%, respectively. The resistance R5 over R20 significantly correlated with forced expiratory volume in 1 second (FEV1). The MedicAid produced a more aggressive challenge than the DeVilbliss nebulizer. Oscillometry can be used to monitor the level of airway hyperresponsiveness following bronchoprovocation tests.

• MeSH
• bronchiální astma diagnóza   patofyziologie   MeSH
• bronchiální hyperreaktivita diagnóza   patofyziologie   MeSH
• bronchoprovokační testy přístrojové vybavení   MeSH
• dítě MeSH
• financování organizované MeSH
• histamin diagnostické užití   MeSH
• lidé MeSH
• methacholinchlorid diagnostické užití   MeSH
• mladiství MeSH
• nebulizátory a vaporizátory MeSH
• oscilometrie MeSH
• spirometrie MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• srovnávací studie MeSH

• MeSH
• aerosolové dávkovače využití   MeSH
• aerosoly MeSH
• aplikace inhalační MeSH
• bronchiální astma farmakoterapie   MeSH
• bronchodilatancia terapeutické užití   MeSH
• cystická fibróza farmakoterapie   MeSH
• deoxyribonukleasy terapeutické užití   MeSH
• dítě MeSH
• dospělí MeSH
• klinická farmakologie MeSH
• lékové roztoky MeSH
• nebulizátory a vaporizátory využití   MeSH
• steroidy terapeutické užití   MeSH
• suspenze MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• Publikační typ
• sborníky MeSH

• Konspekt
• Farmacie. Farmakologie
• NLK Obory
• pneumologie a ftizeologie
• alergologie a imunologie
• farmakoterapie

• MeSH
• bronchiální astma farmakoterapie   MeSH
• dítě MeSH
• kojenec MeSH
• nebulizátory a vaporizátory MeSH
• pregnendiony aplikace a dávkování   MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH

• Konspekt
• Lékařské vědy. Lékařství
• NLK Obory
• alergologie a imunologie
• pediatrie

This contribution is focused on the preparation of a liposomal drug delivery system of erlotinib resisting the nebulization process that could be used for local treatment of non-small-cell lung cancer. Liposomes with different compositions were formulated to reveal their influence on the encapsulation efficiency of erlotinib. An encapsulation efficiency higher than 98 % was achieved for all vesicles containing phosphatidic acid (d ≈ 100 nm, ζ = - 43 mV) even in the presence of polyethylene glycol (d ≈ 150 nm, ζ = - 17 mV) which decreased this value in all other formulas. The three most promising formulations were nebulized by two air-jet and two vibrating mesh nebulizers, and the aerosol deposition in lungs was calculated by tools of computational fluid and particle mechanics. According to the numerical simulations and measurements of liposomal stability, air-jet nebulizers generated larger portion of the aerosol able to penetrate deeper into the lungs, but the delivery is likely to be more efficient when the formulation is administered by Aerogen Solo vibrating mesh nebulizer because of a higher portion of intact vesicles after the nebulization. The leakage of encapsulated drug from liposomes nebulized by this nebulizer was lower than 2 % for all chosen vesicles.

• MeSH
• aplikace inhalační MeSH
• bronchodilatancia MeSH
• erlotinib MeSH
• lékové transportní systémy MeSH
• lidé MeSH
• liposomy MeSH
• nádory plic * MeSH
• nebulizátory a vaporizátory MeSH
• nemalobuněčný karcinom plic * MeSH
• plíce MeSH
• respirační aerosoly a kapénky MeSH
• velikost částic MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH