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British Journal of Clinical Pharmacology Jul 2022The propellants in metered-dose inhalers (MDIs) are powerful greenhouse gases, which account for approximately 13% of the NHS's carbon footprint related to the delivery... (Review)
Review
The propellants in metered-dose inhalers (MDIs) are powerful greenhouse gases, which account for approximately 13% of the NHS's carbon footprint related to the delivery of care. Most MDI use is in salbutamol relievers in patients with poorly controlled disease. The UK lags behind Europe in this regard, with greater reliance on salbutamol MDI and correspondingly greater greenhouse gas emissions, roughly treble that of our European neighbours. There has been a broad switch towards MDIs in asthma treatment in the UK over the last 20 years to reduce financial costs, such that the treatment for two-thirds of asthma patients in the UK is dominated by salbutamol MDI. Strategies that replace overuse of reliever MDIs with regimes emphasising inhaled corticosteroids have the potential to improve asthma control alongside significant reductions in greenhouse gas emissions. Real-world evidence shows that once-daily long-acting combination dry-powder inhalers (DPIs) can improve compliance and asthma control, and reduce the carbon footprint of care. Similarly, maintenance and reliever therapy (MART), which uses combination reliever and inhaled steroids in one device (usually a DPI), can simplify therapy, improve asthma control and reduce greenhouse gas emissions. Both treatment strategies are popular with patients, most of whom would be willing to change treatment to reduce their carbon footprint. By focussing on patients who are currently using high amounts of salbutamol MDI and prioritising inhaled steroids via DPIs, there are golden opportunities to make asthma care in the UK more effective, safer and greener.
Topics: Administration, Inhalation; Albuterol; Asthma; Dry Powder Inhalers; Environment; Greenhouse Gases; Humans; Metered Dose Inhalers
PubMed: 34719810
DOI: 10.1111/bcp.15135 -
Ugeskrift For Laeger Nov 2023Hydrofluorocarbons, the propellants used in metered dose inhalers, are powerful greenhouse gases. However, this review investigates the use of metered dose inhalers... (Review)
Review
Hydrofluorocarbons, the propellants used in metered dose inhalers, are powerful greenhouse gases. However, this review investigates the use of metered dose inhalers which continue to be on the rise in Denmark despite evidence that most patients are treated equally well with dry powder inhalers. If the use of metered dose inhalers in Denmark were reduced to approximately the level seen in Sweden it would lead to a reduction in CO2e comparable with the emissions from the electricity used in 16,500 typical Danish households.
Topics: Humans; Asthma; Nebulizers and Vaporizers; Metered Dose Inhalers; Dry Powder Inhalers; Respiration Disorders; Respiratory Tract Diseases; Administration, Inhalation
PubMed: 37987432
DOI: No ID Found -
The European Respiratory Journal Jul 2022When selecting the best inhaler and drug combination for a patient with respiratory disease, a number of factors should be considered. While efficacy and safety of... (Review)
Review
When selecting the best inhaler and drug combination for a patient with respiratory disease, a number of factors should be considered. While efficacy and safety of medical treatments are always a priority, in recent years the environmental impacts of all aspects of life have become an increasingly necessary consideration and inhaled therapies are no exception. The carbon footprint of an item, individual or organisation is one of the most important and quantifiable environmental impacts, assessed by the amount of greenhouse gases (often expressed in terms of carbon dioxide equivalents) generated throughout the life cycle. The two most commonly prescribed and manufactured inhaler types worldwide are pressurised metered-dose inhalers (pMDIs) containing hydrofluorocarbon (HFC) propellants and dry powder inhalers (DPIs). Most of the carbon footprint of current pMDIs is a result of the propellants that they contain (HFC-134a and HFC-227ea, which are potent greenhouse gases). In comparison, the powder in DPIs is dispersed by the patient's own inhalation, meaning DPIs do not contain a propellant and have a lower carbon footprint than most pMDIs currently available. Soft mist inhalers are another propellant-free option: the device contains a spring, which provides the energy to disperse the aqueous medication. In this review, we examine the published data on carbon footprint data for inhalers, providing an analysis of potential implications for treatment decision making and industry initiatives.
Topics: Administration, Inhalation; Dry Powder Inhalers; Environment; Greenhouse Gases; Humans; Metered Dose Inhalers; Nebulizers and Vaporizers
PubMed: 34916263
DOI: 10.1183/13993003.02106-2021 -
Frontiers in Neuroscience 2022Decision-making is described as a natural process, one among others, consuming free energy in the least time. The thermodynamic tenet explains why data associated with...
Decision-making is described as a natural process, one among others, consuming free energy in the least time. The thermodynamic tenet explains why data associated with decisions display the same patterns as any other data: skewed distributions, sigmoidal cumulative curves, oscillations, and even chaos. Moreover, it is shown that decision-making is intrinsically an intractable process because everything depends on everything else. However, no decision is arbitrary but bounded by free energy, such as resources and propellants, and restricted by mechanisms like molecular, neural, and social networks. The least-time maximation of entropy, equivalent to the minimization of free energy, parallels the optimization of subjective expected utility. As the system attains a state of balance, all driving forces vanish. Then there is no need or use to make further decisions. In general, the thermodynamic theory regards those decisions well-motivated that take into account forces, i.e., causes comprehensively in projecting motions, i.e., consequences.
PubMed: 35153668
DOI: 10.3389/fnins.2022.806160 -
Anais Da Academia Brasileira de Ciencias 2023With the higher requirements of various tactical and technical indicators of the weapon systems, the current research on the ignition and combustion characteristics of...
With the higher requirements of various tactical and technical indicators of the weapon systems, the current research on the ignition and combustion characteristics of different types of solid propellants is not comprehensive. In more complex and harsh environmental conditions, the pressure affects the ignition and combustion characteristics. Therefore, the paper studies the ignition and combustion characteristics of the modified double-base propellants (MDB propellants) and fuel-rich propellants (FR propellants) under low-pressure environment. Combining experiment and theory, the ignition delay time and burning rate of two kinds of solid propellants are compared and analyzed at low pressure by the laser ignition experimental device. The results displayed that the burning flames of the FR and MDB propellant presented evident V-shape and cylindrical, respectively. The flame brightness decreased with the decrease in pressure. With the increase of pressure and heat flux, the ignition delay time of the MDB propellant and the FR propellant decreased. By comparison, Model 2 of the ignition delay time was more effective for the estimation of the ignition delay time of the FR propellant. The experimental results are compared with the three burning rate models, which are the Vielle formula (Model 1), Summerfield formula (Model 2), and B-number burning rate formula (Model 3). The results showed the burning rate was more in accord with Model 3.
PubMed: 37909562
DOI: 10.1590/0001-3765202320220762 -
RSC Advances Mar 2018A new green (chlorine-free) high energy dense oxidizer (HEDO) 2,2,2-trinitroethyl-formate (TNEF) and its propellant formulation based on the hydroxyl-terminated...
A new green (chlorine-free) high energy dense oxidizer (HEDO) 2,2,2-trinitroethyl-formate (TNEF) and its propellant formulation based on the hydroxyl-terminated polybutadiene (HTPB) as a binder was prepared and studied. The new oxidizer TNEF was successfully prepared and characterized by nuclear magnetic resonance (NMR) and FTIR spectrometer. Scanning electron microscopy (SEM) was used to check the crystal morphology of the oxidizer. A high specific impulse ( = 250.1 s) was obtained from the characteristics calculation of the new oxidizer instead of ( = 156.9 s) for the commonly used ammonium perchlorate (AP) by using EXPLO5_V6.03 software. The burning behavior and the burning rate were determined by using a high speed camera. TNEF and the propellant formulations were studied by using nonisothermal thermogravimetric analysis (TGA) and the kinetic parameters of the studied samples were determined by using isoconversional (model-free) methods "Kissinger, Ozawa and Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS)". The results proved that the new oxidizer and its formulation based on HTPB have chlorine-free decomposition products and have higher performance characteristics than the traditional propellants.
PubMed: 35542765
DOI: 10.1039/c8ra01515e -
Cell Communication and Signaling : CCS May 2023Metabolic reprogramming is one of the main characteristics of cancer cells and plays pivotal role in the proliferation and survival of cancer cells. Amino acid is one of... (Review)
Review
Metabolic reprogramming is one of the main characteristics of cancer cells and plays pivotal role in the proliferation and survival of cancer cells. Amino acid is one of the key nutrients for cancer cells and many studies have focused on the regulation of amino acid metabolism, including the genetic alteration, epigenetic modification, transcription, translation and post-translational modification of key enzymes in amino acid metabolism. Long non-coding RNAs (lncRNAs) are composed of a heterogeneous group of RNAs with transcripts of more than 200 nucleotides in length. LncRNAs can bind to biological molecules such as DNA, RNA and protein, regulating the transcription, translation and post-translational modification of target genes. Now, the functions of lncRNAs in cancer metabolism have aroused great research interest and significant progress has been made. This review focuses on how lncRNAs participate in the reprogramming of amino acid metabolism in cancer cells, especially glutamine, serine, arginine, aspartate, cysteine metabolism. This will help us to better understand the regulatory mechanism of cancer metabolic reprogramming and provide new ideas for the development of anti-cancer drugs. Video Abstract.
Topics: Humans; RNA, Long Noncoding; Neoplasms; Epigenesis, Genetic; Glutamine; Protein Processing, Post-Translational
PubMed: 37127605
DOI: 10.1186/s12964-023-01116-1