Evaluation of lung tolerance of ethanol, propylene glycol, and sorbitan monooleate as solvents in medical aerosols.
ABSTRACT Aerosol therapy is an expanding technique allowing administration of drugs acting locally in the bronchial tree and lungs or acting systemically after absorption through the respiratory tract. However, the choice of solvents and adjuvants is a critical step in the formulation process of new drugs. Pulmonary tolerance of ethanol, propylene glycol and sorbitan ester was evaluated in a rat model of intratracheal administration using a Microsprayer in a 4-day toxicity study.
Four groups of Sprague-Dawley rats (11 rats per group, n = 44) have received, on 4 consecutive days 150 microL of solutions containing the solvents, by intratracheal route using a IA-1B-2 inches-Microsprayer (PennCentury, Philadelphia, PA). Once a day, the rats received deionized water (control) or ethanol 10% or propylene glycol 30% or sorbitan monooleate 10%. All rats were sacrificed 24 h after the fourth administration. Biochemical analysis on bronchoalveolar lavage (BAL) fluid was performed on seven rats per group. The respiratory tract of the remaining four rats/group was examined histologically.
Biochemistry and histopathology findings demonstrated that under the conditions tested, deionized water, 10% ethanol, and 30% propylene glycol were tolerated in a qualitatively similar way presenting limited cellular reaction. In contrast, 10% sorbitan monooleate produced an accumulation of foamy macrophages in the lungs and a higher degree of inflammation. In addition, animals in this group showed higher polymorphonuclear neutrophil recruitment and total proteins levels in BAL fluid.
The overall results recommended ranking the vehicles according to the degree of inflammation which was induced: deionized water <10% ethanol < or =30% propylene glycol <10% Tween 80.
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ABSTRACT: Electronic cigarette consumption ('vaping') is marketed as an alternative to conventional tobacco smoking. Technically, a mixture of chemicals containing carrier liquids, flavors, and optionally nicotine is vaporized and inhaled. The present study aims at the determination of the release of volatile organic compounds (VOC) and (ultra)fine particles (FP/UFP) from an e-cigarette under near-to-real-use conditions in an 8-m(3) emission test chamber. Furthermore, the inhaled mixture is analyzed in small chambers. An increase in FP/UFP and VOC could be determined after the use of the e-cigarette. Prominent components in the gas-phase are 1,2-propanediol, 1,2,3-propanetriol, diacetin, flavorings, and traces of nicotine. As a consequence, 'passive vaping' must be expected from the consumption of e-cigarettes. Furthermore, the inhaled aerosol undergoes changes in the human lung that is assumed to be attributed to deposition and evaporation. PRACTICAL IMPLICATIONS: The consumption of e-cigarettes marks a new source for chemical and aerosol exposure in the indoor environment. To evaluate the impact of e-cigarettes on indoor air quality and to estimate the possible effect of passive vaping, information about the chemical characteristics of the released vapor is needed.Indoor Air 06/2012; · 3.30 Impact Factor
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ABSTRACT: With the rapid development of transportation industry and China's economy, the construction and development of low-carbon transportation system is the only way to realize the low-carbon and sustainable development of the transportation industry, and also is an important support to the energy -saving and emission reduction target and the healthy economic development. Based on the existing problems in the transportation system, the article analy zes the necessity of developing low-carbon transportation system, and puts up the three-party interaction model (government-transportation-public) and basic governance model.Energy Procedia 01/2011; 5:1502-1507.
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ABSTRACT: The inhaled route is increasingly developed to deliver locally acting or systemic therapies, and rodent models are used to assess tolerance before clinical studies. Endotracheal intubation of rats with a probe which generates powder aerosols enables controlled administration of drug directly into the respiratory tract. However, preliminary observations of intratracheal powder administration procedures have raised concerns with regard to pulmonary safety. The aim of the present work was to evaluate the safety of intra-tracheal administration of dry powder in a rat model. Sixty animals were administered various volumes of air alone, lactose or magnesium stearate through a Microsprayer(®) (Pencentury, USA). The mass of powder actually delivered to each animal was calculated. Rats were sacrificed immediately after administration, and the lungs, trachea and larynx were removed and examined for gross pathology. The mass of powder delivered varied, the full dose being rarely delivered. About one third of the administration procedures resulted in respiratory failure, and macroscopic pulmonary lesions were observed in about 55% of animals. Lung damages were observed with air alone, lactose and magnesium stearate. In conclusion, artifacts observed with this technique may limit the relevance of the model. These observations are particularly important in the context of regulatory toxicity studies. Corrigendum to “Pulmonary delivery of dry powders to rats tolerability limits of an intra-tracheal administration model” [Int. J. Pharm. 434 (2012) 481–487] The authors regret that the paper published by initially contains the below typing errors: i.e. - The term “Microsprayer” was employed by mistake and corresponds in fact to the “Dry Powder Insufflator™ – Model DP-4”. - The photograph on the Graphical Abstract did not correspond to the “Dry Powder Insufflator™ – Model DP-4 which is presented below.”International Journal of Pharmaceutics 05/2012; 434(1-2):481-7. · 3.99 Impact Factor