-
Journal of the American Chemical Society Mar 2024Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the...
Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the manufacture of polyesters and antifreeze and has a high carbon intensity. Unfortunately, to date, the electrooxidation of propylene under ambient conditions has suffered from a wide product distribution, leading to a low faradic efficiency toward the desired propylene glycol. We undertook mechanistic investigations and found that the reconstruction of Pd to PdO occurs, followed by hydroxide formation under anodic bias. The formation of this metastable hydroxide layer arrests the progressive dissolution of Pd in a locally acidic environment, increases the activity, and steers the reaction pathway toward propylene glycol. Rh-doped Pd further improves propylene glycol selectivity. Density functional theory (DFT) suggests that the Rh dopant lowers the energy associated with the production of the final intermediate in propylene glycol formation and renders the desorption step spontaneous, a concept consistent with experimental studies. We report a 75% faradic efficiency toward propylene glycol maintained over 100 h of operation.
PubMed: 38470826
DOI: 10.1021/jacs.4c00312 -
Molecules (Basel, Switzerland) Dec 2023Binary ethosome vesicles have been developed as flexible lipid vesicles for the enhanced physicochemical stability and skin delivery of drugs. This work aimed to prepare...
Binary ethosome vesicles have been developed as flexible lipid vesicles for the enhanced physicochemical stability and skin delivery of drugs. This work aimed to prepare phloretin-loaded propylene glycol ethosomes (PHL-PGEs) to improve their stability, skin permeability and antioxidant activity. PHL-PGEs were prepared via the ethanol injection method and optimized using different weight ratios of ethanol to propylene glycol (PG). When the ethanol/PG mass ratio changed from 10:0 to 0:10, the encapsulation efficiency and stability of ethosomes increased. At a PHL concentration of 1mg/mL, the EE% was 89.42 ± 2.42 and the DL% was 4.21 ± 0.04, which exhibited their highest values. The encapsulation of the PHL in the PHL-PGEs was strengthened via XRD analysis and FTIR analysis. The results of the in vitro percutaneous permeability test demonstrated that the combined use of ethanol and PG exhibited a notable enhancement in skin permeability, and the skin retention of PHL-PGEs was 1.06 times that of PHL-ethosomes (PHL-Es) and 2.24 times that of the PHL solution. An in vitro antioxidant activity study indicated that solubility and antioxidant activity was potentiated via the nanoencapsulation of phloretin. Therefore, these results confirm the potential of this nanocarrier to enhance physicochemical stability, skin permeability and antioxidant activity.
Topics: Antioxidants; Ethanol; Permeability; Phloretin; Propylene Glycol
PubMed: 38202649
DOI: 10.3390/molecules29010066 -
Current Drug Delivery 2024Nicotine is a fat-soluble substance that is easily absorbed through the skin and mucosal tissues of the human body. However, its properties, such as light exposure, heat...
BACKGROUND
Nicotine is a fat-soluble substance that is easily absorbed through the skin and mucosal tissues of the human body. However, its properties, such as light exposure, heat decomposition, and volatilization, restrict its development and application in external preparations.
OBJECTIVE
This study focused on the preparation of stable nicotine-encapsulated ethosomes.
METHODS
During their preparation, two water-phase miscible osmotic promoters, ethanol and propylene glycol (PG), were added to obtain a stable transdermal delivery system. Skin nicotine delivery was enhanced through the synergistic action of osmotic promoters and phosphatidylcholine in binary ethosomes. Various characteristics of the binary ethosomes were measured, including the vesicle size, particle size distribution, and zeta potential. In order to optimize the ratio of ethanol and PG, the skin permeability test was performed on mice in vitro in a Franz diffusion cell to compare cumulative skin permeabilities. The penetration depth and fluorescence intensity of rhodamine-B-entrapped vesicles in isolated mouse skin samples were observed using laser confocal scanning microscopy.
RESULTS
When ethanol:PG was used in a ratio of 5:5 (w/w), binary ethosomes were found to be the most stable, had the highest encapsulation rate (86.13 ± 1.40), smallest particle size (106.0 ± 11.0) nm, maximum transdermal depth (180 μm), and maximum fluorescence intensity (160 AU). Nicotineencapsulated ethosomes (ethanol: PG = 5:5, w/w) were an efficient and stable transdermal delivery system.
CONCLUSION
The nicotine-encapsulated ethosomes containing ethanol and PG are considered to be safe and reliable as a transdermal administration agent, which does not irritate the skin.
Topics: Mice; Humans; Animals; Liposomes; Skin Absorption; Nicotine; Ethanol; Skin; Administration, Cutaneous; Propylene Glycol
PubMed: 37132146
DOI: 10.2174/1567201820666230428122845 -
Pflugers Archiv : European Journal of... Jun 2024Electronic cigarettes (e-cigarettes), as alternative nicotine delivery methods, has rapidly increased among youth and adults in recent years. However, cardiovascular... (Review)
Review
Electronic cigarettes (e-cigarettes), as alternative nicotine delivery methods, has rapidly increased among youth and adults in recent years. However, cardiovascular safety is an important consideration regarding e-cigarettes usage. e-cigarette emissions, including nicotine, propylene glycol, flavorings, nitrosamine, and metals, might have adverse effects on cardiovascular health. A large body of epidemiological evidence has indicated that e-cigarettes are considered an independent risk factor for increased rates of cardiovascular disease occurrence and death. The incidence and mortality of various types of cardiovascular disease, such as cardiac arrhythmia, hypertension, acute coronary syndromes, and heart failure, have a modest growth in vapers (users of e-cigarettes). Although the underlying biological mechanisms have not been fully understood, studies have validated that oxidative stress, inflammation, endothelial dysfunction, atherosclerosis, hemodynamic effects, and platelet function play important roles in which e-cigarettes work in the human body. This minireview consolidates and discusses the epidemiological and biological links between e-cigarettes and various types of cardiovascular disease.
Topics: Humans; Electronic Nicotine Delivery Systems; Cardiovascular Diseases; Vaping; Animals; Nicotine
PubMed: 38376568
DOI: 10.1007/s00424-024-02925-0 -
Transplantation and Cellular Therapy Nov 2023Patients with systemic light chain (AL) amyloidosis undergoing treatment with high-dose melphalan and autologous stem cell transplantation (HDM/SCT) may develop renal...
Patients with systemic light chain (AL) amyloidosis undergoing treatment with high-dose melphalan and autologous stem cell transplantation (HDM/SCT) may develop renal and cardiac toxicities potentially exacerbated by the co-solvent propylene glycol in conventional melphalan formulations. We investigated the safety and efficacy of propylene glycol-free melphalan (PGF-Mel) during HDM/SCT in patients with AL amyloidosis (ClinicalTrials.gov identifier NCT02994784). The primary objective of this phase II, open-label study was evaluation for renal dysfunction, new cardiac arrhythmias, and postural hypotension related to autonomic dysfunction. Secondary objectives included time to neutrophil and platelet engraftment, treatment-related mortality (TRM), overall hematologic response, organ response, and number of peritransplantation hospitalizations. Twenty-eight patients with AL amyloidosis enrolled, of whom 27 underwent HDM/SCT. PGF-Mel at 140 to 200 mg/m was administered i.v. in 2 equally divided doses. Patients were monitored for up to 30 days after the last administration of PGF-Mel to assess for treatment-related toxicity. Patients were followed for 12 months from the time of treatment with HDM/SCT for evaluation of hematologic and organ responses. Kaplan-Meier analysis was used to estimate progression-free survival. Two patients (7%) developed renal dysfunction, 5 (19%) experienced new cardiac arrhythmias, and 3 (11%) developed orthostatic hypotension. All patients achieved neutrophil and platelet engraftment, at a median of 10 days and 17 days post-HDM/SCT, respectively. TRM on day +100 was 0%. Peritransplantation hospitalization was required for 23 patients (85%). The most common nonhematologic adverse events were diarrhea (93%), fatigue (82%), and nausea (74%). At 6 months post-HDM/SCT, hematologic complete response or very good partial response occurred in 66% of the patients. At 12 months post-HDM/SCT, renal response occurred in 12 of 23 (52%) patients with renal involvement, and cardiac response occurred in 3 of 11 (27%) patients with evaluable cardiac involvement. Our data indicate that PGF-Mel is safe and efficacious as a high-dose conditioning regimen for autologous SCT in patients with AL amyloidosis.
Topics: Humans; Melphalan; Immunoglobulin Light-chain Amyloidosis; Hematopoietic Stem Cell Transplantation; Amyloidosis; Transplantation, Autologous; Kidney Diseases; Arrhythmias, Cardiac
PubMed: 37607644
DOI: 10.1016/j.jtct.2023.08.018 -
Cardiovascular Research Oct 2023Electronic cigarette use has grown exponentially in recent years, and while their popularity has increased, the long-term effects on the heart are yet to be fully... (Review)
Review
Electronic cigarette use has grown exponentially in recent years, and while their popularity has increased, the long-term effects on the heart are yet to be fully studied and understood. Originally designed as devices to assist with those trying to quit traditional combustible cigarette use, their popularity has attracted use by teens and adolescents who traditionally have not smoked combustible cigarettes. Acute effects on the heart have been shown to be similar to traditional combustible cigarettes, including increased heart rate and blood pressure. The main components of electronic cigarettes that contribute to these arrhythmic effects are found in the e-liquid that is aerosolized and inhaled, comprised of nicotine, flavourings, and a combination of vegetable glycerin (VG) and propylene glycol (PG). Nicotine can potentially induce both ventricular and atrial arrhythmogenesis, with both the atrial and ventricular effects resulting from the interactions of nicotine and the catecholamines they release via potassium channels. Atrial arrhythmogenesis, more specifically atrial fibrillation, can also occur due to structural alterations, which happens because of nicotine downregulating microRNAs 133 and 590, both post-transcriptional growth factor repressors. Liquid flavourings and the combination of PG and VG can possibly lead to arrhythmic events by exposing users to acrolein, an aldehyde that stimulates TRPA1 that in turn causes a change towards sympathetic activation and autonomic imbalance. The design of these electronic delivery devices is constantly changing; therefore, it has proven extremely difficult to study the long-term effects on the heart caused by electronic cigarettes but will be important to understand given their rising popularity. The arrhythmic effects of electronic cigarettes appear similar to traditional cigarettes as well; however, a comprehensive review has not been compiled and is the focus of this article.
Topics: Adolescent; Humans; Nicotine; Electronic Nicotine Delivery Systems; Atrial Fibrillation; Propylene Glycol; Glycerol
PubMed: 37517059
DOI: 10.1093/cvr/cvad113 -
Veterinary Medicine and Science Sep 2023Grazing in arid and semi-arid regions faces pregnant ewes with feed restrictions and hence affects the offspring muscle fibre characteristics. Using feed additives that...
Restricted maternal nutrition and supplementation of propylene glycol, monensin sodium and rumen-protected choline chloride during late pregnancy does not affect muscle fibre characteristics of offspring.
BACKGROUND
Grazing in arid and semi-arid regions faces pregnant ewes with feed restrictions and hence affects the offspring muscle fibre characteristics. Using feed additives that enhance nutrient availability during foetal muscle development is expected to alter offspring skeletal muscle characteristics.
OBJECTIVES
This study evaluated the effect of maternal restricted nutrition and supplementation of propylene glycol, monensin sodium and rumen-protected choline chloride on lamb's muscle fibre characteristics.
METHODS
Forty-eight Ghezel ewes were randomly allocated to one of six diets (N = 8) during the last 6 weeks of gestation: ad libitum feed intake (AL); restricted feeding (RF); restricted feeding containing propylene glycol (PG); restricted feeding containing propylene glycol and monensin sodium (MS); restricted feeding containing propylene glycol and rumen-protected choline chloride (RPC); restricted feeding containing propylene glycol, monensin sodium and rumen-protected choline chloride (PMC). The muscle samples were obtained from the semitendinosus muscle of 2-week-old male lambs (n = 5/treatment) via biopsy and were stained and classified as fibre types I, IIA and IIB.
RESULTS
Pre-parturient maternal feed restriction and administration of propylene glycol, monensin sodium and rumen-protected choline chloride had no significant effect on fibre-type composition, fibre density of muscle, muscle cross-sectional area and volume density of fibres (p > 0.05).
CONCLUSIONS
Either maternal dietary restriction or supplementation of nutrient flux-involved additives during late pregnancy did not alter muscle fibre development and had no short-term effects on muscle properties of the resulting offspring as myogenesis occurs in early and mid-gestation, not late gestation. Therefore, maternal nutrition may not be a problematic issue in sheep production in arid and semi-arid areas.
Topics: Pregnancy; Animals; Sheep; Female; Male; Monensin; Choline; Rumen; Propylene Glycol; Muscle Fibers, Skeletal; Dietary Supplements
PubMed: 37556348
DOI: 10.1002/vms3.1239 -
International Journal of Pharmaceutics:... Dec 2023Gene therapy has shown remarkable effectiveness in the management of disease like cancer and inflammation as a revolutionary therapeutic. Nonetheless, therapeutic drug...
Gene therapy has shown remarkable effectiveness in the management of disease like cancer and inflammation as a revolutionary therapeutic. Nonetheless, therapeutic drug target discovery, efficient gene delivery, and gene delivery vehicles continue to be significant obstacles. Due to their effective gene transport capabilities and low immunogenicity, supramolecular polymers have garnered significant interest. Herein, ABHD5 is identified as a potential therapeutic target since it is dysregulated in hepatocellular carcinoma (HCC). Interestingly, the downregulation of ABHD5 could induce programmed death-ligand 1 (PD-L1) expression in liver cancer, which may contribute to the immunosuppression. To overcome the immunosuppression caused by PD-L1, an injectable hydrogel is designed to achieve efficient abhydrolase domain containing 5 (ABHD5) gene delivery via the host-guest interaction with branched polyethyleneimine-g-poly (ethylene glycol), poly (ethylene oxide) and poly (propylene oxide) block copolymers and α-CD (PPA/CD), demonstrating the capability for sustained gene release. The co-assembly hydrogel demonstrates good biocompatibility and enhanced gene transfection efficiency, efficiently triggering tumor cell apoptosis. Overall, the results of this study suggest that ABHD5 is a potential therapeutic target, and that a host-guest-based supramolecular hydrogel could serve as a promising platform for the inhibition of HCC.
PubMed: 37448985
DOI: 10.1016/j.ijpx.2023.100195 -
Environment International Sep 2023E-cigarettes, also known as electronic nicotine delivery systems (ENDS), are mainly used among adolescents and young adults. Similar to traditional cigarettes, different...
E-cigarettes, also known as electronic nicotine delivery systems (ENDS), are mainly used among adolescents and young adults. Similar to traditional cigarettes, different concentrations of nicotine are also added to E-cigarette's liquid (E-liquid), but due to the supplementation of chemicals such as propylene glycol (PG), vegetable glycerin (VG) and flavors, it is difficult to determine the risk after using E-cigarettes. And given to the specificity of the aerosol particle composition and atomization process of E-cigarettes, it is necessary to assess the neurotoxic effects of long-term E-cigarettes use. In this study, two commercial nicotine-containing (5%) and nicotine-free E-liquids were diluted to investigate the neurobehavioral changes and addictive tendencies of developing C. elegans after sub-chronic exposure to E-liquid. The results showed that sub-chronic exposure of E-liquid could lead to impaired growth and development of nematodes, abnormal general neuromotor behavior and advanced learning and memory behavior, and nicotine-containing E-liquid could also lead to increased addiction tendency of nematodes. Although the damage effect of nicotine free E-liquid is smaller than that of the nicotine-containing group, its toxic effect cannot be ignored. Further analysis of the neurotoxicity mechanism found that redox imbalance-mediated mitochondrial stress and aging may be important causes of E-liquid-induced biological damage. The biosafety of e-cigarette aerosols was also included in the assessment. The study found that the heated atomization process did not alter the E-liquid components, and E-cigarette aerosols still have the effect of interfering with the growth and development of nematodes and neurobehavior, and its addictive nature is also of concern. This study can provide new ideas for future studies on the neurotoxic effects and safety assessment of the E-cigarettes, and provide theoretical reference for the study on the injury mechanism of E-cigarettes.
Topics: Adolescent; Humans; Young Adult; Animals; Caenorhabditis elegans; Electronic Nicotine Delivery Systems; Nicotine; Aerosols; Aging; Neurotoxicity Syndromes
PubMed: 37690220
DOI: 10.1016/j.envint.2023.108180 -
Zeitschrift Fur Geburtshilfe Und... Aug 2023Propolis has become one of the most preferred supplements due to its beneficial biological properties. Organic (water and vegetable oils) and chemical (ethyl alcohol,...
BACKGROUND
Propolis has become one of the most preferred supplements due to its beneficial biological properties. Organic (water and vegetable oils) and chemical (ethyl alcohol, propylene glycol, and glycerol) solvents are used for propolis extraction. However, the effects of these chemicals on health should be taken into account.
OBJECTIVES
In this study, the effects of propolis extracts on health were evaluated.
METHODS
32 pregnant Wistar albino rats and 64 neonatal/young adults were given three different extractions of propolis (propylene glycol, water, and olive oil). Histopathological analyses were performed on the liver and brain, and blood samples were taken from the hearts of rats.
RESULTS
Histopathological scoring showed that the intensity of pycnotic hepatocyte, sinusoidal dilatation, and bleeding was high in liver samples of pregnant and baby rats given propylene glycol extract of propolis (p<0.05). Propylene glycol extract caused dilatation of blood vessels and apoptosis of neurons in brain tissue. The histopathological score was significantly lower in liver and brain tissues of rats treated with water and olive oil extract compared to propylene propolis groups (p<0.05). Liver enzyme levels in the blood increased in propylene propolis rats (p<0.05).
CONCLUSION
Histopathological changes and biochemical alterations may indicate that propylene glycol extracts of propolis are more toxic than olive oil and water extracts. Therefore, olive oil and water extracts of propolis are more reliable than propylene glycol extract in pregnant and infant rats.
Topics: Humans; Rats; Animals; Pregnancy; Female; Propolis; Animals, Newborn; Rats, Wistar; Olive Oil; Liver; Propylene Glycol; Central Nervous System
PubMed: 36889342
DOI: 10.1055/a-2010-4009