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1.
PLoS One ; 16(9): e0256730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495991

RESUMO

INTRODUCTION: Recently, electric cigarettes with liquid (e-liquid) were introduced as an alternative to tobacco smoking. They were promoted as possible cessation aids and were considered to be potentially less harmful than traditional tobacco-based cigarettes. However, there is little information on the toxicants present in e-liquids and their possible carcinogenic effects. METHODS: Western blot analysis was performed to identify the protein levels of cancer progression related signal transducers. Patient-derived brain tumor cells (CSC2) were injected into mouse brains and tumor growth was then observed by performing magnetic resonance imaging (MRI) and hematoxylin and eosin (H&E) staining of the whole brain. Immunohistochemistry (IHC) staining and Immunofluorescence staining were performed to study the expression of pEGFR and pERK. RESULTS: Western blotting revealed that e-liquids increased pEGFR and pERK expression in a dose dependent manner. Animal experiments revealed that the e-liquid treated group had accelerated tumor growth and poor prognosis compared to the vehicle group. Histological staining showed activation of pEGFR and pERK in the e-liquid treated group. CONCLUSION: Our study revealed that e-liquid activates pEGFR and pERK, leading to accelerated brain tumor growth and poor prognosis.


Assuntos
Neoplasias Encefálicas/metabolismo , Carcinogênese/efeitos dos fármacos , Sistemas Eletrônicos de Liberação de Nicotina , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glioblastoma/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nicotina/administração & dosagem , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fumar Cigarros/metabolismo , Modelos Animais de Doenças , Receptores ErbB/metabolismo , Feminino , Glioblastoma/patologia , Xenoenxertos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias/métodos , Fosforilação/efeitos dos fármacos , Prognóstico , Propilenoglicol/administração & dosagem , Soluções , Solventes/administração & dosagem , Carga Tumoral/efeitos dos fármacos
2.
Int J Mol Sci ; 21(17)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32825651

RESUMO

The use of electronic nicotine delivery systems (ENDS), also known as electronic-cigarettes (e-cigs), has raised serious public health concerns, especially in light of the 2019 outbreak of e-cig or vaping product use-associated acute lung injury (EVALI). While these cases have mostly been linked to ENDS that contain vitamin E acetate, there is limited research that has focused on the chronic pulmonary effects of the delivery vehicles (i.e., without nicotine and flavoring). Thus, we investigated lung function and immune responses in a mouse model following exposure to the nearly ubiquitous e-cig delivery vehicles, vegetable glycerin (VG) and propylene glycol (PG), used with a specific 70%/30% ratio, with or without vanilla flavoring. We hypothesized that mice exposed sub-acutely to these e-cig aerosols would exhibit lung inflammation and altered lung function. Adult female C57BL/6 mice (n = 11-12 per group) were exposed to filtered air, 70%/30% VG/PG, or 70%/30% VG/PG with a French vanilla flavoring for 2 h a day for 6 weeks. Prior to sacrifice, lung function was assessed. At sacrifice, broncho-alveolar lavage fluid and lung tissue were collected for lipid mediator analysis, flow cytometry, histopathology, and gene expression analyses. Exposures to VG/PG + vanilla e-cig aerosol increased lung tidal and minute volumes and tissue damping. Immunophenotyping of lung immune cells revealed an increased number of dendritic cells, CD4+ T cells, and CD19+ B cells in the VG/PG-exposed group compared to air, irrespective of the presence of vanilla flavoring. Quantification of bioactive lung lipids demonstrated a >3-fold increase of 2-arachidonoylglycerol (2-AG), an anti-inflammatory mediator, and a 2-fold increase of 12-hydroxyeicosatetraenoic acid (12-HETE), another inflammatory mediator, following VG/PG exposure, with or without vanilla flavoring. This suggests that e-cig aerosol vehicles may affect immunoregulatory molecules. We also found that the two e-cig aerosols dysregulated the expression of lung genes. Ingenuity Pathway Analysis revealed that the gene networks that are dysregulated by the VG/PG e-cig aerosol are associated with metabolism of cellular proteins and lipids. Overall, our findings demonstrate that VG and PG, the main constituents of e-liquid formulations, when aerosolized through an e-cig device, are not harmless to the lungs, since they disrupt immune homeostasis.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Aromatizantes/toxicidade , Pneumonia/induzido quimicamente , Pneumonia/imunologia , Animais , Modelos Animais de Doenças , Feminino , Expressão Gênica/efeitos dos fármacos , Glicerol/administração & dosagem , Glicerol/toxicidade , Imunoglobulinas/metabolismo , Imunofenotipagem , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Pneumonia/fisiopatologia , Propilenoglicol/administração & dosagem , Propilenoglicol/toxicidade , Testes de Função Respiratória
3.
Theriogenology ; 149: 16-24, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32229351

RESUMO

Spotted wolffish Anarhichas minor reproduction in captivity is dependent on in vitro fertilization. However, low sperm volume with relatively low cell concentration and the lack of gametes synchronization (simultaneous availability of mature eggs and sperm) represent a challenge for the industry. Thus, the development of protocols for sperm storage are crucial. Four sequential experiments were conducted to optimize a sperm cryopreservation protocol for this species. First, three different cryoprotectants (DMSO; 1, 2-propanediol; and methanol) at different concentrations (5, 10, and 20%) were tested for their toxicity. No significant differences (p > 0.05) were detected between the control samples and cryoprotectants at concentration up to 10% DMSO, 10% propanediol, and 20% methanol in terms of motility parameters. Second, using the highest non-toxic concentrations of cryoprotectants, sperm was cryopreserved in 0.5 mL straws, at different distances from the liquid nitrogen (1.5, 2.5, 4.5, and 7.5 cm) that correspond to different freezing rates. Motility parameters after freezing/thawing decreased for all the cryoprotectants (p < 0.001), however, methanol had the lowest protective capacity while DMSO the highest. Afterwards, two different thawing rates (1 min at 5 °C; and 25 s at 10 °C) were tested using only 10% DMSO and 10% propanediol. Both for the DMSO and propanediol, there were no significant differences (p > 0.05) between the two thawing rates. The best results were obtained using 10% DMSO. Finally, the fertilization capacity of cryopreserved sperm (10% DMSO and thawed at 5 °C for 1 min) was tested against fresh sperm using two spermatozoa:egg ratios and 4 h gametes contact time. The ratio of eggs with normal cell cleavage, abnormal cleavage or undeveloped were counted at the 2-4 cell stage. Cryopreserved sperm showed lower fertilization capacity at a concentration of 5 × 104 spermatozoa:egg compared with fresh sperm (p < 0.001). At a concentration of 5 × 105 spermatozoa:egg, similar fertilizations rates to the fresh sperm were obtained. The presence of the cryoprotectant DMSO during the 4 h contact time did not affect the fertilization rate or the percentage of embryos with abnormal cleavage (p > 0.05). To cryopreserve spotted wolffish sperm it is recommended to use 10% DMSO, loaded in 0.5 mL straws, freeze at a height between 4.5 (-14.05 °C/min) and 7.5 cm (-5.9 °C/min) from liquid nitrogen for 10 min and thaw for 1 min at 5 °C (177.9 °C/min). In vitro fertilization with cryopreserved sperm should be performed with a concentration of at least 5 × 105 spermatozoa per egg.


Assuntos
Criopreservação/veterinária , Crioprotetores/administração & dosagem , Perciformes/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Criopreservação/instrumentação , Criopreservação/métodos , Crioprotetores/toxicidade , Dimetil Sulfóxido/administração & dosagem , Fertilização in vitro/métodos , Fertilização in vitro/veterinária , Masculino , Metanol/administração & dosagem , Propilenoglicol/administração & dosagem , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos
5.
Shock ; 54(1): 119-127, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31425404

RESUMO

INTRODUCTION: Suprarenal aortic cross clamping (SRACC) and reperfusion may cause acute pulmonary hypertension and multiple organ failure. HYPOTHESIS: The organic mononitrites of 1,2-propanediol (PDNO), an nitric oxide donor with a very short half-life, are a more efficient pulmonary vasodilator and attenuator of end-organ damage and inflammation without significant side effects compared with nitroglycerin and inorganic nitrite in a porcine SRACC model. METHODS: Anesthetized and instrumented domestic pigs were randomized to either of four IV infusions until the end of the experiment (n = 10 per group): saline (control), PDNO (45 nmol kg min), nitroglycerin (44 nmol kg min), or inorganic nitrite (a dose corresponding to PDNO). Thereafter, all animals were subjected to 90 min of SRACC and 10 h of reperfusion and protocolized resuscitation. Hemodynamic and respiratory variables as well as blood samples were collected and analysed. RESULTS: During reperfusion, mean pulmonary arterial pressure and pulmonary vascular resistance were significantly lower, and stroke volume was significantly higher in the PDNO group compared with the control, nitroglycerin, and inorganic nitrite groups. In parallel, mean arterial pressure, arterial oxygenation, and fraction of methaemoglobin were similar in all groups. The serum concentration of creatinine and tumor necrosis factor alpha were lower in the PDNO group compared with the control group during reperfusion. CONCLUSIONS: PDNO was an effective pulmonary vasodilator and appeared superior to nitroglycerin and inorganic nitrite, without causing significant systemic hypotension, impaired arterial oxygenation, or methaemoglobin formation in an animal model of SRACC and reperfusion. Also, PDNO may have kidney-protective effects and anti-inflammatory properties.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Nitroglicerina/farmacologia , Propilenoglicóis/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Feminino , Hipertensão Pulmonar/fisiopatologia , Infusões Intravenosas , Masculino , Nitritos/administração & dosagem , Nitritos/farmacologia , Nitroglicerina/administração & dosagem , Propilenoglicol/administração & dosagem , Propilenoglicol/farmacologia , Propilenoglicóis/administração & dosagem , Suínos
6.
Cancer Prev Res (Phila) ; 13(2): 145-152, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31619441

RESUMO

Electronic cigarette (e-cig) use is continuing to increase, particularly among youth never-smokers, and is used by some smokers to quit. The acute and chronic toxicity of e-cig use is unclear generally in the context of increasing reports of inflammatory-type pneumonia in some e-cig users. To assess lung effects of e-cigs without nicotine or flavors, we conducted a pilot study with serial bronchoscopies over 4 weeks in 30 never-smokers, randomized either to a 4-week intervention with the use of e-cigs containing only 50% propylene glycol (PG) and 50% vegetable glycerine or to a no-use control group. Compliance to the e-cig intervention was assessed by participants sending daily puff counts and by urinary PG. Inflammatory cell counts and cytokines were determined in bronchoalveolar lavage (BAL) fluids. Genome-wide expression, miRNA, and mRNA were determined from bronchial epithelial cells. There were no significant differences in changes of BAL inflammatory cell counts or cytokines between baseline and follow-up, comparing the control and e-cig groups. However, in the intervention but not the control group, change in urinary PG as a marker of e-cig use and inhalation was significantly correlated with change in cell counts (cell concentrations, macrophages, and lymphocytes) and cytokines (IL8, IL13, and TNFα), although the absolute magnitude of changes was small. There were no significant changes in mRNA or miRNA gene expression. Although limited by study size and duration, this is the first experimental demonstration of an impact of e-cig use on inflammation in the human lung among never-smokers.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Glicerol/efeitos adversos , Pulmão/efeitos dos fármacos , Propilenoglicol/efeitos adversos , Administração por Inalação , Adulto , Biomarcadores/análise , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Broncoscopia , Estudos Transversais , Citocinas/genética , Citocinas/imunologia , Ex-Fumantes , Feminino , Perfilação da Expressão Gênica , Glicerol/administração & dosagem , Humanos , Pulmão/diagnóstico por imagem , Pulmão/imunologia , Masculino , não Fumantes , Projetos Piloto , Propilenoglicol/administração & dosagem , Propilenoglicol/urina , Fumantes , Fumar/efeitos adversos , Fumar/terapia , Fumar/urina , Abandono do Hábito de Fumar/métodos , Adulto Jovem
7.
Int J Pharm ; 575: 118920, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31863880

RESUMO

The hypothesis for the investigation was that the overall mechanism of action of skin penetration enhancers is best explained by the Solubility-Physicochemical-Thermodynamic (SPT) theory. To our knowledge, this is the first report of the application of SPT theory in transdermal/topical/enhancer research. The SPT theory puts forward the concept that the mode of action of enhancers is related to solubility parameters, physicochemical interactions and thermodynamic activity. This paper discusses these concepts by using experimentally derived permeation data, various physicochemical and solubility parameters (ingredient active gap (IAG), ingredient skin gap (ISG), solubility of active in the formulation (SolV) and the formulation solubility in the skin (SolS)) generated by using FFE (Formulating for Efficacy™ - ACT Solutions Corp) software. These studies suggest that there is an inverse relationship between measured flux and IAG values given that there is an optimum ingredient skin gap, SolV and SolS ratio. The study demonstrated that the flux is actually proportional to a gradient of thermodynamic activity rather than the concentration and maximum skin penetration and deposition can be achieved when the drug is at its highest thermodynamic activity.


Assuntos
Benzoquinonas/administração & dosagem , Excipientes/administração & dosagem , Nicotina/administração & dosagem , Absorção Cutânea , Administração Cutânea , Azepinas/administração & dosagem , Azepinas/química , Benzoquinonas/química , Eucaliptol/administração & dosagem , Eucaliptol/química , Excipientes/química , Humanos , Técnicas In Vitro , Modelos Teóricos , Nicotina/química , Ácido Oleico/administração & dosagem , Ácido Oleico/química , Polissorbatos/administração & dosagem , Polissorbatos/química , Propilenoglicol/administração & dosagem , Propilenoglicol/química , Pirrolidinonas/administração & dosagem , Pirrolidinonas/química , Pele/metabolismo , Software , Solubilidade , Termodinâmica
8.
BMC Pharmacol Toxicol ; 20(1): 28, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077262

RESUMO

BACKGROUND: Concern about intoxication by e-liquid is growing as calls to poison control centers have increased since their introduction. Only three cases of intoxication by injection have been reported worldwide. Our case is unique because of the precise follow-up of a patient who survived a lethal dose of self-injected e-liquid, without other co-intoxication. CASE PRESENTATION: A 51-year-old male presented to the Emergency Department after injecting himself intravenously (IV) in the forearm with 10 mL of e-liquid (1000 mg of nicotine diluted in propylene glycol). An agitation phase was followed by coma and bradypnoea requiring mechanical ventilation. The patient developed a transitory neurological impairment with the appearance of tetraparesis, gaze palsy and myoclonus due to nicotinic syndrome. The arterial blood gas (ABG) analysis confirmed uncompensated lactic acidosis with an elevated anion gap, which is an expected effect of propylene glycol. The toxicology screen indicated the presence of nicotine and cotinine in the blood and excluded the presence of concomitant intoxication. The patient recovered without sequelae. CONCLUSION: Even a small quantity of intravenous (IV) e-liquid can lead to an acute intoxication and fatal outcomes due to the toxic effects of nicotine. This case might help emergency doctors cope with acute intoxication by injection of e-liquid and increase their comprehension of the two main substances, nicotine and propylene glycol with overview of their pharmacodynamics and kinetic effects.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nicotina/toxicidade , Propilenoglicol/toxicidade , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Propilenoglicol/administração & dosagem
9.
Physiol Rep ; 7(10): e14093, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31140749

RESUMO

Electronic cigarette uses propylene glycol and glycerol to deliver nicotine and flavors to the lungs. Given the hundreds of different brands, the thousands of flavors available and the variations in nicotine concentrations, it is likely that electronic cigarette settings and e-liquid composition affect the size distribution of particles emitted and ultimately pulmonary deposition. We used the inExpose e-cigarette extension to study two separate modes of operation of electronic cigarettes, namely power-controlled and the temperature-controlled. We also assessed several e-liquids based on propylene glycol and glycerol concentrations, nicotine content, and selected monomolecular flavoring agents (menthol, vanillin, and maltol). Particle size distribution was measured using a Condensation Particle Counter and a Scanning Mobility Particle Sizer spectrometer. Lung deposition was predicted using the International Commission on Radiological Protection model. For all resistance coils, increase in power delivery generated larger particles while maintaining a higher coil temperature generated smaller particles. Increase in glycerol concentration led to the generation of larger particles. With regard to flavors, we showed that despite minor effect of menthol and maltol, vanillin dramatically increased particle size. Presence of nicotine also increased particle size. Finally, particles emitted by the electronic cigarette were predicted to mainly deposit in the alveoli and conditions generating larger particle sizes led to a reduction in predicted lung deposition. This study shows that coil temperature, propylene glycol and glycerol concentrations, presence of nicotine, and flavors affect the size of particles emitted by an electronic cigarette, directly affecting predicted lung deposition of these particles.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Pulmão/metabolismo , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Temperatura , Vaping , Administração por Inalação , Aerossóis , Desenho de Equipamento , Aromatizantes/administração & dosagem , Aromatizantes/química , Aromatizantes/metabolismo , Glicerol/administração & dosagem , Glicerol/química , Glicerol/metabolismo , Humanos , Modelos Biológicos , Nicotina/química , Nicotina/metabolismo , Agonistas Nicotínicos/química , Agonistas Nicotínicos/metabolismo , Tamanho da Partícula , Propilenoglicol/administração & dosagem , Propilenoglicol/química , Propilenoglicol/metabolismo
10.
Annu Rev Anal Chem (Palo Alto Calif) ; 12(1): 23-39, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-30848928

RESUMO

The study of e-cigarette aerosol properties can inform public health while longer-term epidemiological investigations are ongoing. The determination of aerosol levels of known toxins, as well as of molecules with unknown inhalation toxicity profiles, affords specific information for estimating the risks of e-cigarettes and for uncovering areas that should be prioritized for further investigation.


Assuntos
Aerossóis/análise , Sistemas Eletrônicos de Liberação de Nicotina , Nicotina/análise , Aerossóis/administração & dosagem , Aerossóis/efeitos adversos , Técnicas de Química Analítica/métodos , Aromatizantes/administração & dosagem , Aromatizantes/efeitos adversos , Aromatizantes/análise , Glicerol/administração & dosagem , Glicerol/efeitos adversos , Glicerol/análise , Humanos , Nicotina/administração & dosagem , Nicotina/efeitos adversos , Propilenoglicol/administração & dosagem , Propilenoglicol/efeitos adversos , Propilenoglicol/análise , Saúde Pública
11.
Cardiovasc Intervent Radiol ; 42(6): 905-914, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30761410

RESUMO

PURPOSE: To investigate the novel zein-based non-adhesive precipitating liquid embolic HEIE1_2017. MATERIALS AND METHODS: Zein-based liquid embolics are an own class of embolization material. In this study, HEIE1_2017, a novel zein-based liquid embolic, was investigated. Visibility was assessed in vitro in CT and MRI phantoms, embolization characteristics were assessed in vivo in the kidneys of 12 pigs. Components of HEIE1_2017 were zein as occlusion material, ethanol as solvent, and iodized oil as radiopaque material. HEIE1_2017 was used in pure (HEI-PURE) and manually modified (HEI-MOD) form and compared with 6% ethylene vinyl alcohol copolymer (EVOH). Different radiological methods (CT, MRI, DSA, cone-beam CT, and micro-CT) and histopathologic analyses were applied to compare visibility and vascular occlusion patterns. RESULTS: In CT phantoms, all embolics were definitely visible as hyperdense materials. In MRI phantoms, signal-to-noise ratio was highest for HEI-PURE, followed by HEI-MOD and EVOH. In all kidneys, embolization procedures were technically successful and without complications. In DSA, all embolics were definitely visible during and after embolization. Only EVOH caused substantial artifacts in cone-beam CT and CT. In micro-CT and histopathology, HEI-PURE showed a homogeneous occlusion from segmental arteries to glomerular capillaries. HEI-MOD demonstrated the deepest vascular penetration (up to the level of peritubular capillaries), but with an inhomogeneous distribution. For EVOH, there was inhomogeneous vascular occlusion from segmental arteries to glomerular capillaries. CONCLUSION: HEIE1_2017 is a promising novel zein-based liquid embolic. Further preclinical and clinical studies with higher case numbers and long-term follow-up are needed to further assess the value of this embolic material.


Assuntos
Quimioembolização Terapêutica/métodos , Diatrizoato de Meglumina/administração & dosagem , Etanol/administração & dosagem , Rim/diagnóstico por imagem , Propilenoglicol/administração & dosagem , Zeína/administração & dosagem , Angiografia Digital , Animais , Artefatos , Óleo Iodado , Imageamento por Ressonância Magnética/métodos , Modelos Animais , Imagens de Fantasmas , Radiografia , Suínos , Tomografia Computadorizada por Raios X , Raios X
12.
J Anal Toxicol ; 43(1): 45-50, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30192935

RESUMO

Electronic cigarettes (ECIGs) are battery-powered devices that heat and vaporize solutions containing propylene glycol (PG) and/or vegetable glycerin (VG), nicotine and possible trace flavorants to produce an inhalable aerosol. The heating process can lead to the formation of reactive oxygen species (ROS), which are linked to various oxidative damage-initiated diseases. Several studies in the literature have addressed ROS emissions in ECIG aerosols, but the effects of power, ECIG device design and liquid composition on ROS are relatively unknown. In addition, ROS emissions have not been examined in the emerging high power, sub-Ohm device (SOD) category. In this study, an acellular 2',7'-dichlorofluorescin (DCFH) probe technique was optimized to measure ROS in ECIG aerosols. The technique was deployed to measure ROS emissions in SOD and supra-Ohm ECIGs while varying power, heater coil head design and liquid composition (PG/VG ratio and nicotine concentration). Liquids were made from analytical standards of PG, VG and nicotine and contained no flavorants. At high powers, ROS emissions in ECIGs and combustible cigarettes were similar. Across device designs, ROS emissions were uncorrelated with power (R2 = 0.261) but were highly correlated with power per unit area (R2 = 0.78). It was noticed that an increase in the VG percentage in the liquid yielded higher ROS flux, and nicotine did not affect ROS emissions. ROS emissions are a function of device design and liquid composition at a given power. For a given liquid composition, a promising metric for predicting ROS emissions across device designs and operating conditions is power per unit area of the heating coil. Importantly, ROS formation is significant even when the ECIG liquid consists of pure analytical solutions of PG and VG; it can therefore be viewed as intrinsic to ECIG operation and not solely a by-product of particular flavorants, contaminants or additives.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Glicerol/química , Nicotina/química , Agonistas Nicotínicos/química , Propilenoglicol/química , Espécies Reativas de Oxigênio/análise , Vaping , Aerossóis , Qualidade de Produtos para o Consumidor , Composição de Medicamentos , Desenho de Equipamento , Glicerol/administração & dosagem , Glicerol/efeitos adversos , Temperatura Alta , Humanos , Exposição por Inalação , Teste de Materiais , Nicotina/administração & dosagem , Nicotina/efeitos adversos , Agonistas Nicotínicos/administração & dosagem , Agonistas Nicotínicos/efeitos adversos , Propilenoglicol/administração & dosagem , Propilenoglicol/efeitos adversos , Espécies Reativas de Oxigênio/efeitos adversos , Medição de Risco , Vaping/efeitos adversos
13.
Nicotine Tob Res ; 21(9): 1274-1278, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-30346584

RESUMO

INTRODUCTION: Free radicals and carbonyls produced by electronic cigarettes (e-cigs) have the potential to inflict oxidative stress. Recently, Juul e-cigs have risen drastically in popularity; however, there is no data on nicotine and oxidant yields from this new e-cig design. METHODS: Aerosol generated from four different Juul flavors was analyzed for carbonyls, nicotine, and free radicals. The e-liquids were analyzed for propylene glycol (PG) and glycerol (GLY) concentrations. To determine the effects of e-liquid on oxidant production, Juul pods were refilled with nicotine-free 30:70 or 60:40 PG:GLY with or without citral. RESULTS: No significant differences were found in nicotine (164 ± 41 µg/puff), free radical (5.85 ± 1.20 pmol/puff), formaldehyde (0.20 ± 0.10 µg/puff), and acetone (0.20 ± 0.05 µg/puff) levels between flavors. The PG:GLY ratio in e-liquids was ~30:70 across all flavors with GLY being slightly higher in tobacco and mint flavors. In general, when Juul e-liquids were replaced with nicotine-free 60:40 PG:GLY, oxidant production increased up to 190% and, with addition of citral, increased even further. CONCLUSIONS: Juul devices produce free radicals and carbonyls, albeit, at levels substantially lower than those observed in other e-cig products, an effect only partially because of a low PG:GLY ratio. Nicotine delivery by these devices was as high as or higher than the levels previously reported from cigarettes. IMPLICATIONS: These findings suggest that oxidative stress and/or damage resulting from Juul use may be lower than that from cigarettes or other e-cig devices; however, the high nicotine levels are suggestive of a greater addiction potential.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Radicais Livres/análise , Nicotina/análise , Estresse Oxidativo/fisiologia , Aromatizantes/administração & dosagem , Aromatizantes/análise , Radicais Livres/administração & dosagem , Humanos , Nicotina/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Propilenoglicol/administração & dosagem , Propilenoglicol/análise
14.
Eur J Pharm Sci ; 125: 223-231, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30316975

RESUMO

Imiquimod (IMQ) is an immunostimulant drug topically used for the treatment of actinic keratosis and basal cell carcinoma. IMQ formulation and skin delivery is difficult because of its very low solubility in the most of pharmaceutical excipients and very poor skin penetration properties. The purpose of this study was to develop a microemulsion to optimize imiquimod skin delivery using d­α­tocopherol polyethylene glycol-1000 succinate (TPGS) as surfactant (so as to take advantage of its thickening properties) and isostearic acid as oil phase. This fatty acid was selected since it has demonstrated a good solubilizing power for imiquimod and it has also shown to contribute to its therapeutic activity. We have built pseudo-ternary diagrams using two different co-surfactants (Transcutol® and propylene glycol - PG) in a 1:1 ratio with TPGS and then selected microemulsions in the clear and viscous regions of the diagrams. The systems were characterized in terms of rheology and X-ray scattering; additionally, the capability to promote IMQ skin uptake was evaluated ex-vivo on a porcine skin model. All the formulations selected in the gel-microemulsion regions behaved as viscoelastic solids; X-rays scattering experiments revealed in all cases the presence of an ordered lamellar structure, but with differences in terms of interlamellar distance and flexibility between Transcutol® and PG-containing systems. A higher flexibility and a greater hydrophobic volume, possibly interconnected at some point, was associated to the use of Transcutol® and had an impact on the microemulsion capacity to solubilize IMQ as well as on the capability to enhance drug uptake into the skin. The best performing gel-like microemulsion was composed of ≈26% of water, ≈21% of isostearic acid, ≈26% of TPGS and ≈27% of Transcutol® and accumulated, after 6 h of contact, 3.0 ±â€¯1.1 µg/cm2 of IMQ. This value is higher than the one reported in the literature for the commercial cream (1.9 ±â€¯0.8 µg/cm2), despite the 4-times lower concentration of the vehicle (13 mg/g for the microemulsion vs 50 mg/g for the commercial cream).


Assuntos
Adjuvantes Imunológicos/química , Antineoplásicos/química , Imiquimode/química , Tensoativos/química , Vitamina E/química , Adjuvantes Imunológicos/administração & dosagem , Administração Cutânea , Animais , Antineoplásicos/administração & dosagem , Química Farmacêutica , Emulsões , Etilenoglicóis/administração & dosagem , Etilenoglicóis/química , Imiquimode/administração & dosagem , Propilenoglicol/administração & dosagem , Propilenoglicol/química , Pele/metabolismo , Absorção Cutânea , Ácidos Esteáricos/administração & dosagem , Ácidos Esteáricos/química , Tensoativos/administração & dosagem , Suínos , Vitamina E/administração & dosagem
15.
Inhal Toxicol ; 30(4-5): 159-168, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29932004

RESUMO

Direct physicochemical interactions between the major components of electronic cigarette liquids (e-liquids): glycerol (VG) and propylene glycol (PG), and lung surfactant (LS) were studied by determining the dynamic surface tension under a simulated breathing cycle using drop shape method. The studies were performed for a wide range of concentrations based on estimated doses of e-liquid aerosols (up to 2500 × the expected nominal concentrations) and for various VG/PG ratios. The results are discussed as relationships among mean surface tension, surface tension amplitude, and surface rheological properties (dilatational elasticity and viscosity) versus concentration and composition of e-liquid. The results showed that high local concentrations (>200 × higher than the estimated average dose after a single puffing session) may induce measurable changes in biophysical activity of LS; however, only ultra-high e-liquid concentrations inactivated the surfactant. Physiochemical characterization of e-liquids provide additional insights for the safety assessment of electronic nicotine delivery systems (ENDS).


Assuntos
Produtos Biológicos/química , Sistemas Eletrônicos de Liberação de Nicotina , Glicerol/química , Propilenoglicol/química , Vaping , Aerossóis , Simulação por Computador , Elasticidade , Glicerol/administração & dosagem , Glicerol/efeitos adversos , Exposição por Inalação , Modelos Químicos , Análise Numérica Assistida por Computador , Propilenoglicol/administração & dosagem , Propilenoglicol/efeitos adversos , Medição de Risco , Tensão Superficial , Vaping/efeitos adversos , Viscosidade
16.
Basic Clin Pharmacol Toxicol ; 122(5): 523-530, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29281181

RESUMO

Polymedicated neonates and young infants may be at risk of harmful cumulative exposure to toxic excipients like ethanol, propylene glycol and benzyl alcohol during routine clinical care. The aim of this study was to calculate the cumulative daily alcohol exposure (mg/kg/day) in polymedicated neonates and infants and compare these levels to the tolerance limits found in guidelines published by European Medicines Agency (EMA). As part of the SEEN study, all medicinal products administered to neonates and infants were recorded. All included neonates received ≥2 medicinal products/day and infants ≥3 medicinal products/day. Daily excipient levels were calculated based on quantities obtained from manufacturers or databases. Excipient levels were compared to tolerance limits proposed by the EMA. Altogether, 470 neonates and 160 infants were included, recording 4207 prescriptions and 316 products. In total, 45% (n = 288) of patients were exposed to an alcohol of interest; 2% (n = 14) were exposed to benzyl alcohol (BA), 38% (n = 237) to ethanol and 23% (n = 146) to propylene glycol (PG). Of the total number of prescriptions involving ethanol-containing medicinal products (n = 334), 51% would alone exceed tolerance limit of 6 mg/kg/day. Of the total number of prescriptions involving PG-containing medicinal products (n = 174), 70% would alone exceed a maximum tolerance limit of 50 mg/kg/day. Maximal daily exposure to ethanol (1563 mg/kg/day) or PG (954 mg/kg/day) exceeded the tolerance limits recommended by EMA 260.5 and 19.1 times, respectively. Tolerance limits for ethanol and PG as proposed by the EMA are frequently exceeded in polymedicated neonates and infants due to the cumulative effect of these alcohols. Alternative formulations may minimize excipient exposure.


Assuntos
Etanol/administração & dosagem , Excipientes/administração & dosagem , Propilenoglicol/administração & dosagem , Fatores Etários , Relação Dose-Resposta a Droga , Composição de Medicamentos , Etanol/efeitos adversos , Excipientes/efeitos adversos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Dose Máxima Tolerável , Nível de Efeito Adverso não Observado , Polimedicação , Propilenoglicol/efeitos adversos , Estudos Retrospectivos , Medição de Risco
17.
Regul Toxicol Pharmacol ; 91: 103-108, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29066335

RESUMO

The selection of a suitable vehicle for administration of NCEs in non-clinical studies is always a challenge for poorly soluble compounds. Challenge is increased if the dose formulation is intended for intravenous (i.v.) administration where isotonic, biologically compatible pH and solution form is an absolute requirement. Vehicle toxicity and tolerability data are not readily available for a number of combination vehicles therefore, an i.v. tolerability studies was planned in rats with 5% v/v Pharmasolve (NMP), 45% v/v Propylene glycol (PG) and 50% v/v Polyethylene glycol (PEG) 400 combination, at dose volume of 0.5, 1, 2 and 5 mL/kg body weight for 28 days. The vehicle combination was administered via lateral tail vein and effects on clinical signs, body weights, feed consumption, clinical pathology and histopathology were evaluated. Clinical signs of toxicity like tremors, convulsions and death were noticed at 5 mL/kg during the course of the study. At 2 mL/kg, injection site injury without systemic toxicity was noticed. In conclusion, 1 mL/kg of a combination vehicle of 5% NMP, 45% PG and 55% PEG 400 can be administered intravenously once-a-day up to 28 days without any discomfort or injury to rats.


Assuntos
Polietilenoglicóis/efeitos adversos , Propilenoglicol/efeitos adversos , Pirrolidinonas/efeitos adversos , Administração Intravenosa/métodos , Animais , Química Farmacêutica , Excipientes/administração & dosagem , Excipientes/efeitos adversos , Feminino , Concentração de Íons de Hidrogênio , Masculino , Polietilenoglicóis/administração & dosagem , Propilenoglicol/administração & dosagem , Pirrolidinonas/administração & dosagem , Ratos , Ratos Wistar , Testes de Toxicidade/métodos
18.
Inhal Toxicol ; 29(5): 197-205, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28651446

RESUMO

OBJECTIVE: To determine the effect of an acute (1 week) and chronic (3 weeks) exposure to E-cigarette (E-cig) emissions on mucociliary clearance (MCC) in murine lungs. METHODS: C57BL/6 male mice (age 10.5 ± 2.4 weeks) were exposed for 20 min/day to E-cigarette aerosol generated by a Joyetech 510-T® E-cig containing either 0% nicotine (N)/propylene glycol (PG) for 1 week (n = 6), or 3 weeks (n = 9), or 2.4% N/PG for one week (n = 6), or 3 weeks (n = 9), followed by measurement of MCC. Control mice (n = 15) were not exposed to PG alone, or N/PG. MCC was assessed by gamma camera following aspiration of 99mtechnetium aerosol and was expressed as the amount of radioactivity removed from both lungs over 6 hours (MCC6hrs). Venous blood was assayed for cotinine levels in control mice and in mice exposed for 3-weeks to PG alone and N/PG. RESULTS: MCC6hrs in control mice and in mice acutely exposed to PG alone and N/PG was similar, averaging (±1 standard deviation) 8.6 ± 5.2%, 7.5 ± 2.8% and 11.2 ± 5.9%, respectively. In contrast, chronic exposure to PG alone stimulated MCC6hrs (17.2 ± 8.0)% and this stimulation was significantly blunted following chronic exposure to N/PG (8.7 ± 4.6)% (p < .05). Serum cotinine levels were <0.5 ng/ml in control mice and in mice exposed to PG alone, whereas, N/PG exposed mice averaged 14.6 ± 12.0 ng/ml. CONCLUSIONS: In this murine model, a chronic, daily, 20 min-exposure to N/PG, but not an acute exposure, slowed MCC, compared to exposure to PG alone and led to systemic absorption of nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Depuração Mucociliar/efeitos dos fármacos , Nicotina/administração & dosagem , Nicotina/toxicidade , Propilenoglicol/administração & dosagem , Propilenoglicol/toxicidade , Administração por Inalação , Animais , Cotinina , Esquema de Medicação , Pulmão , Masculino , Camundongos , Camundongos Endogâmicos C57BL
19.
Respir Res ; 18(1): 33, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28183298

RESUMO

We designed a crossover and placebo-controlled trial to investigate the impact of a 1-h acute vaping session of nicotine-free and flavour-free e-liquid on the pulmonary functions and respiratory mechanics of healthy and asthmatic individuals. This study shows that a 1-h vaping session of a high-grade and contaminant-free mixture of propylene glycol and glycerol using a commercially available electronic cigarette performed in a controlled environment does not significantly impact pulmonary functions, respiratory mechanics or symptoms in healthy or asthmatic subjects.


Assuntos
Asma/fisiopatologia , Glicerol/efeitos adversos , Pulmão/fisiopatologia , Propilenoglicol/efeitos adversos , Testes de Função Respiratória , Vaping/efeitos adversos , Administração por Inalação , Adulto , Estudos Cross-Over , Feminino , Glicerol/administração & dosagem , Humanos , Masculino , Nicotina , Efeito Placebo , Propilenoglicol/administração & dosagem
20.
Domest Anim Endocrinol ; 59: 105-115, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28063291

RESUMO

This study determined the influence of a short-term glucogenic nutritional treatment on circulating concentrations of glucose, insulin, insulin-like growth factor 1 (IGF-1), nonesterified fatty acids (NEFA), and urea, and on their correspondent levels in follicular fluid (FF) collected 12 h after the end of the treatment. After estrous synchronization with intravaginal progestagen-impregnated sponges, 20 Sarda ewes were randomly allocated into two experimental groups (GLU and WAT) and, from day 7 to day 10 (day 0 = day of sponge removal), the GLU group was gavaged with a glycogenic mixture, whereas the WAT group was gavaged with water (control group). Follicular development was stimulated by FSH administration from day 8 to 10. At day 11, ovaries were collected and follicular fluid processed. Plasma changes were assessed from day 6 to 11. In GLU group, circulating concentration of glucose (P < 0.0001), insulin (P < 0.0001), and IGF-1 (P < 0.01) rose significantly, whereas NEFA and urea concentrations decreased (P < 0.0001), as compared with controls. In particular, in FF the higher glucose concentrations found in GLU ewes compared with controls (P < 0.0001) were not accompanied by any increase in insulin and IGF-1 concentrations. NEFA (P < 0.0001) and urea (P < 0.0001) were lower in FF of GLU than WAT group, although NEFA clearance in the ovary proved to be less efficient than at the systemic level. No significant difference between groups was found in FF concentrations of pregnancy-associated plasma protein A (a protease regulating the levels of free IGF-1 in follicles), glutathione, and in its total antioxidant capacity. These results suggest that glycogenic mixture administration creates a suitable follicular microenvironment for the conception period in dairy ewes.


Assuntos
Glicemia/fisiologia , Fertilização/fisiologia , Hormônio Foliculoestimulante/farmacologia , Glicerol/farmacologia , Propilenoglicol/farmacologia , Ovinos/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Ácidos Graxos não Esterificados/sangue , Feminino , Glicerol/administração & dosagem , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Folículo Ovariano , Gravidez , Progesterona/sangue , Propilenoglicol/administração & dosagem , Ureia/sangue
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