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1.
Ecotoxicol Environ Saf ; 271: 116002, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38277972

RESUMEN

Propylene glycol (PG) and vegetable glycerin (VG) are the most common solvents used in electronic cigarette liquids. No long-term inhalation toxicity assessments have been performed combining conventional and multi-omics approaches on the potential respiratory effects of the solvents in vivo. In this study, the systemic toxicity of aerosol generated from a ceramic heating coil-based e-cigarette was evaluated. First, the aerosol properties were characterized, including carbonyl emissions, the particle size distribution, and aerosol temperatures. To determine toxicological effects, rats were exposed, through their nose only, to filtered air or a propylene glycol (PG)/ glycerin (VG) (50:50, %W/W) aerosol mixture at the target concentration of 3 mg/L for six hours daily over a continuous 28-day period. Compared with the air group, female rats in the PG/VG group exhibited significantly lower body weights during both the exposure period and recovery period, and this was linked to a reduced food intake. Male rats in the PG/VG group also experienced a significant decline in body weight during the exposure period. Importantly, rats exposed to the PG/VG aerosol showed only minimal biological effects compared to those with only air exposure, with no signs of toxicity. Moreover, the transcriptomic, proteomic, and metabolomic analyses of the rat lung tissues following aerosol exposure revealed a series of candidate pathways linking aerosol inhalation to altered lung functions, especially the inflammatory response and disease. Dysregulated pathways of arachidonic acids, the neuroactive ligand-receptor interaction, and the hematopoietic cell lineage were revealed through integrated multi-omics analysis. Therefore, our integrated multi-omics approach offers novel systemic insights and early evidence of environmental-related health hazards associated with an e-cigarette aerosol using two carrier solvents in a rat model.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Glicerol , Masculino , Femenino , Ratas , Animales , Glicerol/toxicidad , Glicerol/análisis , Verduras , Multiómica , Proteómica , Propilenglicol/toxicidad , Propilenglicol/análisis , Solventes , Aerosoles/análisis
2.
NMR Biomed ; 36(4): e4632, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34676601

RESUMEN

The synthesis and turnover of triglyceride in adipose tissue involves enzymes with preferences for specific fatty acid classes and/or regioselectivity regarding the fatty acid position within the glycerol moiety. The focus of the current study was to characterize both the composition of fatty acids and their positional distribution in triglycerides of biopsied human subcutaneous adipose tissue, from subjects with wide ranges of body mass index (BMI) and insulin sensitivity, using 13 C nuclear magnetic resonance (NMR) spectroscopy. The triglyceride sn2 position was significantly more enriched with monounsaturated fatty acids compared with that of sn1,3, while the abundance of saturated fatty acids was significantly lower in the sn2 position compared with that of sn1,3. Furthermore, the analysis revealed significant positive correlations between the total fraction of palmitoleic acid with both BMI and insulin sensitivity scores (homeostatic model assessment of insulin resistance index). Additionally, we established that 13 C NMR chemical shifts for ω-3 signals, centered at 31.9 ppm, provided superior resolution of the most abundant fatty acid species, including palmitoleate, compared with the ω-2 signals that were used previously. 13 C NMR spectroscopy reveals for the first time a highly nonhomogenous distribution of fatty acids in the glycerol sites of human adipose tissue triglyceride, and that these distributions are correlated with different phenotypes, such as BMI and insulin sensitivity.


Asunto(s)
Resistencia a la Insulina , Humanos , Tejido Adiposo/química , Ácidos Grasos/análisis , Ácidos Grasos Insaturados , Glicerol/análisis , Espectroscopía de Resonancia Magnética , Triglicéridos/análisis , Isótopos de Carbono
3.
Chem Res Toxicol ; 36(8): 1355-1360, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37439580

RESUMEN

The presence and toxicological risks of synthetic coolants in electronic nicotine delivery systems (ENDS) have not been thoroughly studied. We identified the synthetic coolant menthone 1,2-glycerol ketal (MGK) in a menthol-flavored e-liquid at a concentration of ∼170 µg/mL. We also detected MGK in aerosols resulting from heating the e-liquid with an electronic waterpipe. MGK was initially detected in the e-liquid by two-dimensional gas chromatography-time-of-flight mass spectrometry. To avoid potential analytical artifacts that could result from heating samples in the injection port of the gas chromatograph, quantitation of MGK in the e-liquid was accomplished using a liquid chromatography-tandem mass spectrometry method. Following recent reports identifying other synthetic coolants in e-liquids, these results add knowledge about inhalation exposures from ENDS use and suggest the importance of future research to study the potential inhalation toxicity related to the use of MGK-containing e-liquids in ENDS devices. Furthermore, the results demonstrate the ability to quantify ketals in e-liquids using liquid chromatography methods.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Fumar en Pipa de Agua , Nicotina/análisis , Mentol/análisis , Glicerol/análisis , Cromatografía de Gases y Espectrometría de Masas , Aerosoles/análisis , Aromatizantes/análisis
4.
Fa Yi Xue Za Zhi ; 39(5): 457-464, 2023 Oct 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38006265

RESUMEN

OBJECTIVES: To establish the GC-MS qualitative and quantitative analysis methods for the synthetic cannabinoids, its main matrix and additives in suspicious electronic cigarette (e-cigarette) oil samples. METHODS: The e-cigarette oil samples were analyzed by GC-MS after diluted with methanol. Synthetic cannabinoids, its main matrix and additives in e-cigarette oil samples were qualitatively analyzed by the characteristic fragment ions and retention time. The synthetic cannabinoids were quantitatively analyzed by using the selective ion monitoring mode. RESULTS: The linear range of each compound in GC-MS quantitative method was 0.025-1 mg/mL, the matrix recovery rate was 94%-103%, the intra-day precision relative standard deviations (RSD) was less than 2.5%, and inter-day precision RSD was less than 4.0%. Five indoles or indazole amide synthetic cannabinoids were detected in 25 e-cigarette samples. The main matrixes of e-cigarette samples were propylene glycol and glycerol. Additives such as N,2,3-trimethyl-2-isopropyl butanamide (WS-23), glycerol triacetate and nicotine were detected in some samples. The content range of synthetic cannabinoids in 25 e-cigarette samples was 0.05%-2.74%. CONCLUSIONS: The GC-MS method for synthesizing cannabinoid, matrix and additive in e-cigarette oil samples has good selectivity, high resolution, low detection limit, and can be used for simultaneous qualitative and quantitative analysis of multiple components; The explored fragment ion fragmentation mechanism of the electron bombardment ion source of indole or indoxamide compounds helps to identify such substances or other compounds with similar structures in cases.


Asunto(s)
Cannabinoides , Sistemas Electrónicos de Liberación de Nicotina , Drogas Ilícitas , Cromatografía de Gases y Espectrometría de Masas/métodos , Drogas Ilícitas/análisis , Indazoles/química , Glicerol/análisis , Indoles/química , Iones
5.
Molecules ; 27(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36144531

RESUMEN

This research work investigates the development of alginate-based films incorporating phenolic compounds extracted from Amaranthus cruentus grain using different solvents. Alginate, glycerol, and amaranth grain phenolic compounds at various concentrations were used to produce the films. An experimental Central Composite Rotatable Design (CCRD) was used to evaluate the effect of these variables on different film's properties, i.e., water vapor permeability, hydrophobicity, moisture content, solubility, thermal, mechanical, and optical properties. This study demonstrated that high phenolic compound content and antioxidant capacity were obtained from amaranth grain using ethanol as the extraction solvent. Alginate films incorporating amaranth phenolic compounds were successfully manufactured, and this study can be used to tailor the formulation of alginate films containing amaranth phenolic compounds, depending on their final food application. For example, less flexible but more resistant and water-soluble films can be produced by increasing the alginate concentration, which was confirmed by a Principal Component Analysis (PCA) and Partial Least Squares (PLS) analysis. This study showed that active alginate films with amaranth phenolic compounds can be tailored to be used as food packaging material with potential antioxidant activity.


Asunto(s)
Amaranthus , Alginatos , Antioxidantes/análisis , Antioxidantes/farmacología , Grano Comestible/química , Etanol/análisis , Glicerol/análisis , Fenoles/análisis , Extractos Vegetales , Solventes/análisis , Vapor/análisis
6.
Molecules ; 27(18)2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36144592

RESUMEN

Polar lipids were extracted from residual biomass of hemp (Cannabis sativa L.) by-products with EtOH and partitioned into aqueous and chloroform fractions. The chloroform fractions were studied for their lipid composition using solid-phase extraction (SPE) followed by UHPLC/HRMS and NMR analyses. The 1H NMR and gravimetric yield of SPE indicated triacylglycerols covered ≥ 51.3% of the chloroform fraction of hemp seed hulls and hemp cake. UHPLC/HRMS analyses of remaining polar lipids led to the identification of nine diacylglycerols (DAGs), six lysophosphatidylcholines (LPCs), five lysophosphatidylethanolamines (LPEs), eight phosphatidylethanolamines (PEs), and thirteen phosphatidylcholines (PCs) for the first time from hemp seed hulls. The regiospecificity of fatty acyl substitutes in glycerol backbone of individual phospholipids were assigned by analyzing the diagnostic fragment ions and their intensities. The heat-map analysis suggested that DAG 18:2/18:2, 1-LPC 18:2, 1-LPE 18:2, PE 18:2/18:2, and PC 18:2/18:2 were the predominant molecules within their classes, supported by the fact that linoleic acid was the major fatty acid covering > 41.1% of the total fatty acids determined by GC-FID analysis. The 31P NMR analysis confirmed the identification of phospholipids and suggested PC covers ≥ 37.9% of the total phospholipid present in hemp by-products. HPLC purification led to the isolation of 1,2-dilinoleoylphosphatidylcholine and 1-palmitoyl-2-linoleoylphosphatidylcholine. These two major PCs further confirmed the UHPLC/HRMS finding.


Asunto(s)
Cannabis , Cannabis/química , Cloroformo , Cromatografía Líquida de Alta Presión , Diglicéridos , Ácidos Grasos , Cromatografía de Gases y Espectrometría de Masas , Glicerol/análisis , Ácidos Linoleicos , Lisofosfatidilcolinas , Espectrometría de Masas , Fosfatidilcolinas/química , Fosfatidiletanolaminas , Fosfolípidos/análisis , Triglicéridos
7.
J Sci Food Agric ; 102(12): 5512-5522, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35365861

RESUMEN

BACKGROUND: Red pitaya peel (RPP) is a good source of polysaccharides, which can be used in the production of biodegradable material. Betacyanins in it possess antioxidant and pH-sensitive properties. However, RPP is commonly discarded during fruit processing. This study aimed to develop real-time intelligent film using RPP to evaluate pork freshness. RESULTS: Real-time intelligent films were developed with film-forming substrates (FFS) composed of 60-100% (w/w) RPP and 0-4% (v/w) glycerol in pH 4.3 ~ 8.0. Rheology tests revealed that the FFS exhibited shear-thinning behavior. Fourier-transform infrared (FTIR) analysis showed that molecules in the RPP interacted with glycerol and formed hydrogen bonds. It showed that the film developed with FFS of 80% RPP and 2% (v/w) glycerol had strong molecular interaction, dense structure, and optimal tensile strength and elongation at break. Film with pH adjusted to 7.0 had greater sensitivity to ammonia than film that was prepared at an original pH of 4.3, so this film was used to monitor freshness of pork. A visible change in the color of the film was observed during the spoiling process of pork, which correlated with the accumulated total volatile base nitrogen. CONCLUSION: Based on its sensitivity to ammonia, the film made of 80% (w/w) RPP and 2% (v/w) glycerol at pH 7.0 was recommended for use in monitoring the freshness of protein-rich food. Our findings are of great significance for ensuring meat quality and safety and for reducing food waste. © 2022 Society of Chemical Industry.


Asunto(s)
Carne de Cerdo , Carne Roja , Eliminación de Residuos , Amoníaco , Animales , Antocianinas/análisis , Embalaje de Alimentos , Glicerol/análisis , Concentración de Iones de Hidrógeno , Carne/análisis , Carne Roja/análisis , Porcinos
8.
Anal Chem ; 93(43): 14432-14439, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34669385

RESUMEN

Accurate and comprehensive identification of residual glycerides in biodiesel is an important part of fuel characterization due to the impact of glycerides on the fuel physicochemical properties. However, analysis of bound glycerol in biodiesel samples faces challenges due to lack of readily available standards of structurally complex glyceride species in nontraditional biodiesel feedstocks and a risk of misannotation in the presence of impurities in gas chromatographic separations. Here, we evaluate methane and isobutane chemical ionization-single quadrupole mass spectrometry combined with high-temperature gas chromatography separations for mapping monoacylglycerols, diacylglycerols, and triacylglycerols in biodiesel. Unlike electron impact ionization, which produces mostly in-source fragments, isobutane chemical ionization spectra of tetramethylsilyl-derivatized monoacylglycerols and diacylglycerols are dominated by molecular ions and M-SiO(CH3)3+ ions, which provide important diagnostic information. We demonstrate the utility of isobutane chemical ionization in identifying structurally complex glycerolipid standards as well as species in biodiesel samples from different plant and animal feedstocks.


Asunto(s)
Biocombustibles , Glicéridos , Animales , Biocombustibles/análisis , Cromatografía de Gases y Espectrometría de Masas , Glicerol/análisis , Temperatura
9.
Chem Res Toxicol ; 34(8): 1846-1849, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-34347480

RESUMEN

E-cigarette liquids (e-liquids) contain propylene glycol (PG) and/or glycerol (GL) to deliver flavorants/nicotine. It has recently been suggested that the PG:GL ratio in e-cigarette reservoirs changes during vaping, leaving almost entirely GL after aerosolizing much of a 30:70 PG:GL mixture. To evaluate this directly, we analyzed e-liquids from e-cigarettes before and after aerosolization using 4 different coils, and aerosol samples generated using high and low e-liquid levels. The PG:GL ratios of initial and final e-liquids and aerosol samples were comparable. This is important because a large change in e-liquid composition could substantially alter the aerosol profile during a vaping session.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Glicerol/análisis , Propilenglicol/análisis , Aerosoles/análisis , Aromatizantes/análisis , Humanos , Espectroscopía de Resonancia Magnética , Vapeo
10.
Mutagenesis ; 36(2): 129-142, 2021 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-33769537

RESUMEN

In vitro (geno)toxicity assessment of electronic vapour products (EVPs), relative to conventional cigarette, currently uses assays, including the micronucleus and Ames tests. Whilst informative on induction of a finite endpoint and relative risk posed by test articles, such assays could benefit from mechanistic supplementation. The ToxTracker and Aneugen Clastogen Evaluation analysis can indicate the activation of reporters associated with (geno)toxicity, including DNA damage, oxidative stress, the p53-related stress response and protein damage. Here, we tested for the different effects of a selection of neat e-liquids, EVP aerosols and Kentucky reference 1R6F cigarette smoke samples in the ToxTracker assay. The assay was initially validated to assess whether a mixture of e-liquid base components, propylene glycol (PG) and vegetable glycerine (VG) had interfering effects within the system. This was achieved by spiking three positive controls into the system with neat PG/VG or phosphate-buffered saline bubbled (bPBS) PG/VG aerosol (nicotine and flavour free). PG/VG did not greatly affect responses induced by the compounds. Next, when compared to cigarette smoke samples, neat e-liquids and bPBS aerosols (tobacco flavour; 1.6% freebase nicotine, 1.6% nicotine salt or 0% nicotine) exhibited reduced and less complex responses. Tested up to a 10% concentration, EVP aerosol bPBS did not induce any ToxTracker reporters. Neat e-liquids, tested up to 1%, induced oxidative stress reporters, thought to be due to their effects on osmolarity in vitro. E-liquid nicotine content did not affect responses induced. Additionally, spiking nicotine alone only induced an oxidative stress response at a supraphysiological level. In conclusion, the ToxTracker assay is a quick, informative screen for genotoxic potential and mechanisms of a variety of (compositionally complex) samples, derived from cigarettes and EVPs. This assay has the potential for future application in the assessment battery for next-generation (smoking alternative) products, including EVPs.


Asunto(s)
Aneugénicos/toxicidad , Sistemas Electrónicos de Liberación de Nicotina , Glicerol/toxicidad , Pruebas de Mutagenicidad/métodos , Nicotiana/toxicidad , Nicotina/toxicidad , Propilenglicol/toxicidad , Aerosoles/efectos adversos , Aerosoles/análisis , Animales , Fumar Cigarrillos/efectos adversos , Daño del ADN , Glicerol/análisis , Humanos , Ratones , Ratones Endogámicos C57BL , Células Madre Embrionarias de Ratones , Mutágenos/toxicidad , Nicotina/análisis , Estrés Oxidativo , Propilenglicol/análisis , Medición de Riesgo , Humo/efectos adversos , Fumar/efectos adversos
11.
Molecules ; 26(9)2021 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-33922286

RESUMEN

The U.S. Food and Drug Administration's (FDA's) Center for Veterinary Medicine (CVM) has been investigating reports of pets becoming ill after consuming jerky pet treats since 2007. Renal failure accounted for 30% of reported cases. Jerky pet treats contain glycerin, which can be made from vegetable oil or as a byproduct of biodiesel production. Glycidyl esters (GEs) and 3-monochloropropanediol esters (3-MCPDEs) are food contaminants that can form in glycerin during the refining process. 3-MCPDEs and GEs pose food safety concerns, as they can release free 3-MCPD and glycidol in vivo. Evidence from studies in animals shows that 3-MCPDEs are potential toxins with kidneys as their main target. As renal failure accounted for 30% of reported pet illnesses after the consumption of jerky pet treats containing glycerin, there is a need to develop a screening method to detect 3-MCPDEs and GEs in glycerin. We describe the development of an ultra-high-pressure liquid chromatography/quadrupole time-of-flight (UHPLC/Q-TOF) method for screening glycerin for MCPDEs and GEs. Glycerin was extracted and directly analyzed without a solid-phase extraction procedure. An exact mass database, developed in-house, of MCPDEs and GEs formed with common fatty acids was used in the screening.


Asunto(s)
Cromatografía Líquida de Alta Presión , Compuestos Epoxi/análisis , Contaminación de Alimentos , Glicerol/análisis , Glicerol/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , alfa-Clorhidrina/análisis , Animales , Ésteres , Análisis de los Alimentos
12.
J Am Chem Soc ; 142(25): 10905-10909, 2020 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-32510211

RESUMEN

Plasmonic sensors are promising for ultrasensitive chemical and biological analysis. However, there are increasing experimental findings that cannot be well addressed by theoretical calculations, including the nonlinear dependence of the plasmonic peak wavelength on the refractive index (RI) and the ultrahigh sensitivity beyond the theoretical limit. The gap between experiments and theoretical calculations is that the bulk RI (BRI) used for calculation could be different from the interfacial RI (IRI) determining the electromagnetic response as a result of the interaction of molecules with the surface. But there is still no method to determine the IRI. Herein, we quantitatively determine the IRI by disentangling the surface RI (SRI) from the BRI. The obtained IRI can be directly applied in theoretical calculations to reliably reflect the experimental response and rigorously guide the design of plasmonic sensors. Moreover, it can be a fundamental dimensionless number to describe the light-matter interaction at the interface.


Asunto(s)
Refractometría , Resonancia por Plasmón de Superficie/métodos , Adsorción , Glicerol/análisis , Glicerol/química , Modelos Químicos
13.
Small ; 16(7): e1905013, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31880080

RESUMEN

Active tumor targeting involves the decoration of nanomaterials (NMs) with oncotropic vector biomolecules that selectively recognize certain antigens on malignant cells or in the tumor microenvironment. This strategy can facilitate intracellular uptake of NM through specific interactions such as receptor-mediated endocytosis and can lead to prolonged retention in the malignant tissues by preventing rapid efflux from the tumor. Here, the design of actively targeting, renally excretible bimodal dendritic polyglycerols (dPGs) for diagnostic cancer imaging is described. Single-domain antibodies (sdAbs) specifically binding to the epidermal growth factor receptor (EGFR) are employed herein as targeting warheads owing to their small size and high affinity for their corresponding antigen. The dPGs equipped with EGFR-targeting feature are compared head-to-head with their nontargeting counterparts in terms of interaction with EGFR-overexpressing cells in vitro as well as accumulation at receptor-positive tumors in vivo. Experimental results reveal a higher specificity and preferential tumor accumulation for the α-EGFR dPGs, resulting from the introduction of active targeting capabilities on their backbone. These results highlight the potential for improving the tumor uptake properties of dPGs by strategic use of sdAb functionalization, which can ultimately prove useful to the development of ultrasmall NM with highly specific tumor accumulation.


Asunto(s)
Técnicas y Procedimientos Diagnósticos , Glicerol , Neoplasias , Polímeros , Anticuerpos de Dominio Único , Endocitosis , Receptores ErbB/metabolismo , Glicerol/análisis , Células Hep G2 , Humanos , Nanoestructuras , Neoplasias/diagnóstico por imagen , Polímeros/análisis , Unión Proteica , Anticuerpos de Dominio Único/metabolismo , Microambiente Tumoral
14.
Yeast ; 37(9-10): 549-557, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32410256

RESUMEN

The selection of Starmerella bacillaris strains to be used with Saccharomyces cerevisiae as mixed cultures has been recently suggested in order to produce wines containing lower ethanol and higher glycerol concentrations and to promote fructose degradation due to their fructophilic character. However, studies about effects of such mixed starter cultures on phenolic compounds, which are responsible for the colour and health-enhancing properties in red wines, are currently lacking. Therefore, in this work, the influence of sequential inoculated fermentation (SIF) with Starm. bacillaris and S. cerevisiae on phenolic content of monovarietal Sangiovese wine was evaluated by fermentations at laboratory scale. Axenic fermentations (AXFs) with S. cerevisiae were performed as control. S. cerevisiae attained higher cell densities in AXF compared with SIF. The experimental wines obtained by SIF showed significant lower ethanol and higher glycerol concentrations, whereas no significant difference was detected in colour intensity. The total phenol index reached significantly lower values in SIF. Furthermore, the wines produced by SIF contained higher concentrations of vitisin A that has a greater colour stability than the anthocyanin monomer. Finally, a lower content of both free anthocyanins and flavan-3-ols, key compounds for wine quality possessing also health-enhancing properties, was found in wines obtained by SIF. On the contrary, no significant difference was detected on flavonol concentration between SIF and AXF. This study highlighted that the use of sequential inoculum of Starm. bacillaris and S. cerevisiae can contribute to increasing the colour stability of red wines, even if at the expense of compounds with health properties.


Asunto(s)
Color , Fermentación , Flavonoides/química , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Vino/análisis , Antocianinas/análisis , Cultivo Axénico/métodos , Benzofuranos/análisis , Etanol/análisis , Etanol/metabolismo , Flavonoides/análisis , Glicerol/análisis , Glicerol/metabolismo , Fenoles/análisis , Vitis , Vino/clasificación
15.
Chem Res Toxicol ; 33(2): 576-583, 2020 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-31950825

RESUMEN

An electronic cigarette (e-cigarette) is a product used to smoke aerosol by heating a solution of "e-liquid" that consists of propylene glycol (PG) and glycerol (GLY) containing nicotine and flavors. In this study, thermal decomposition products generated from three brands of e-cigarettes were determined at various electric power levels. When using neat PG or GLY instead of e-liquid, propylene oxide was detected only in the gas phase from PG and not detected from GLY. In contrast, glycidol was detected only from GLY and not from PG. Almost all of the glyoxal and acrolein was detected from GLY, but formaldehyde and methyl glyoxal were detected from both PG and GLY. Using commercially available e-liquids, the same results were obtained. Nearly all chemical compounds generated from e-cigarettes have a carbon number of 3 or less except for nicotine and flavors. We measured chemical compounds generated from e-cigarettes at various electric power levels (1-85 W). At an electric power of 10 W, the generation of chemical compounds was very low; however, when the electric power exceeded 40 W, it increased exponentially. As thermal decomposition products of e-liquid, acetaldehyde, acrolein, and propylene oxide mainly occur as gaseous matter, while glyoxal, methylglyoxal, and glycidol mainly occur as particulate matter. Formaldehyde exits in both gaseous and particulate matter forms. Thermal decomposition products can be divided into three groups: thermal decomposition products originating from PG and GLY, those originating from other sources, and those directly generated. Concentrations of these thermal decomposition products were mostly higher than those in traditional cigarettes. In particular, thermal decomposition products generated from one of the studied e-cigarettes were very high; e.g., formaldehyde reached 4400 µg/15 puffs at 50 W. E-cigarette users must know that hazardous substances are generated even within the recommended electric power limits.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Glicerol/análisis , Nicotina/análisis , Material Particulado/análisis , Propilenglicol/análisis , Temperatura , Estructura Molecular
16.
Biotechnol Bioeng ; 117(11): 3345-3355, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32678455

RESUMEN

With the aggravation of environmental pollution and energy crisis, the sustainable microbial fermentation process of converting glycerol to 1,3-propanediol (1,3-PDO) has become an attractive alternative. However, the difficulty in the online measurement of glycerol and 1,3-PDO creates a barrier to the fermentation process and then leads to the residual glycerol and therefore, its wastage. Thus, in the present study, the four-input artificial neural network (ANN) model was developed successfully to predict the concentration of glycerol, 1,3-PDO, and biomass with high accuracy. Moreover, an ANN model combined with a kinetic model was also successfully developed to simulate the fed-batch fermentation process accurately. Hence, a soft sensor from the ANN model based on NaOH-related parameters has been successfully developed which cannot only be applied in software to solve the difficulty of glycerol and 1,3-PDO online measurement during the industrialization process, but also offer insight and reference for similar fermentation processes.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Clostridium butyricum/metabolismo , Fermentación/fisiología , Redes Neurales de la Computación , Glicoles de Propileno , Reactores Biológicos/microbiología , Medios de Cultivo/análisis , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Glicerol/análisis , Glicerol/metabolismo , Cinética , Glicoles de Propileno/análisis , Glicoles de Propileno/metabolismo
17.
J Surg Res ; 253: 127-138, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32353638

RESUMEN

BACKGROUND: Noncompressible hemorrhage is the leading cause of preventable death in military and civilian trauma. Our aim was to examine the effect of adenosine, lidocaine, and magnesium (Mg2+; ALM) on cardiovascular and cerebral function in a porcine hepatic hemorrhage model. MATERIALS AND METHODS: Pigs (59.1 ± 0.34 kg) were anesthetized, instrumented, and randomly assigned into sham (n = 6), saline controls (n = 10) or ALM (n = 10) groups before laparoscopic liver resection. After 30 min, groups received 4 mL/kg 3% NaCl ± ALM bolus (Phase 1) followed 60 min later with 3 mL/kg/h 0.9% NaCl ± ALM drip (4 h; Phase 2), then transfusion. Hemodynamics, carotid artery flow, and intracranial pressure were measured continuously. Microdialysis samples were analyzed for metabolites. RESULTS: Saline controls had 20% mortality (mean survival time: 307 ± 38 min) with no ALM deaths over 6 h. Bolus administration increased mean arterial pressure (MAP) in both groups, and drip led to further increases to 62 ± 10 mmHg in controls compared with a steady fall to 47 ± 8 mmHg in ALM group at 240 min. The lower MAP was associated with a dramatic fall in systemic vascular resistance and improved oxygen delivery. ALM drip significantly increased cardiac output and stroke volume with lower dP/dtMin, indicating a less stiff heart. ALM drip also significantly decreased cerebral perfusion pressure, reduced cerebral oxygen consumption (28%), and reduced brain glycerol (60%), lactate (47%), and relative expression of hypoxia-inducible factor (38%) compared with saline controls. CONCLUSIONS: ALM therapy improved cardiac function and oxygen delivery by lowering systemic vascular resistance after noncompressible hemorrhage. ALM also appeared to protect the brain at hypotensive MAPs with significantly lower cerebral perfusion pressure, lower O2 consumption, and significantly lower cortical lactate and glycerol levels compared to saline controls.


Asunto(s)
Fluidoterapia/métodos , Hipotensión/terapia , Hipoxia Encefálica/prevención & control , Resucitación/métodos , Choque Hemorrágico/terapia , Adenosina/administración & dosificación , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Química Encefálica/efectos de los fármacos , Modelos Animales de Enfermedad , Esquema de Medicación , Quimioterapia Combinada/métodos , Femenino , Glicerol/análisis , Humanos , Hipotensión/etiología , Hipoxia Encefálica/etiología , Subunidad alfa del Factor 1 Inducible por Hipoxia/análisis , Infusiones Intravenosas/métodos , Inyecciones Intravenosas/métodos , Ácido Láctico/análisis , Lidocaína/administración & dosificación , Hígado/irrigación sanguínea , Hígado/lesiones , Magnesio/administración & dosificación , Oxígeno/metabolismo , Choque Hemorrágico/etiología , Volumen Sistólico/efectos de los fármacos , Sus scrofa , Resistencia Vascular/efectos de los fármacos , Vasodilatación/efectos de los fármacos
18.
Food Microbiol ; 90: 103460, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32336379

RESUMEN

The use of Saccharomyces and non-Saccharomyces yeast species as mixed starters has potential advantages over pure culture fermentation due to increased wine complexity based on modification of metabolites of oenological interest. In this work, the effects of initial oxygenation on fermentation performance, chemical and volatile composition of French Colombard wine fermented with Hanseniaspora vineae and Saccharomyces cerevisiae in sequential inoculations were investigated in 1 L flasks. Although dominated by S. cerevisiae at the middle-end of fermentation, initial aeration for 1 day boosted H. vineae populations, and allowed H. vineae to coexist longer with S. cerevisiae in mixed cultures compared to no aeration, and suppressed S. cerevisiae later in the fermentation, which resulted in extended fermentation time. More important, the major fermentation products and volatile compounds were significantly modified by aeration and different from no aeration fermentation. The wines produced by aeration of mixed fermentations were characterized with higher amounts of glycerol, lactic acid and acetate esters, and lower levels of ethanol, higher alcohol and ethyl fatty acid esters. The aeration had more potential to shape the quality of wines and diversify the aromatic characteristics relative to simple mixed inoculation, as indicated by PCA analysis. Our results suggested that the impact of early aeration on yeast physiology extends beyond the aeration phase and influences fermentation activity, chemical and aromatic compounds in the following anaerobic stage. The aeration for a short time during the cell growth stage in mixed fermentation is therefore a potential means to increase the aromatic diversity and quality of wine, possibly providing an alternative approach to meet the expectations of wine consumers for diverse aromatic qualities.


Asunto(s)
Fermentación , Hanseniaspora/metabolismo , Oxígeno/metabolismo , Saccharomyces cerevisiae/metabolismo , Vino/análisis , Vino/microbiología , Alcoholes/análisis , Etanol/análisis , Glicerol/análisis , Ácido Láctico/análisis , Odorantes/análisis
19.
Neurocrit Care ; 32(1): 135-144, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31037640

RESUMEN

BACKGROUND: There is no uniform definition for cerebral microdialysis (CMD) probe location with respect to focal brain lesions, and the impact of CMD-probe location on measured molecule concentrations is unclear. METHODS: We retrospectively analyzed data of 51 consecutive subarachnoid hemorrhage patients with CMD-monitoring between 2010 and 2016 included in a prospective observational cohort study. Microdialysis probe location was assessed on all brain computed tomography (CT) scans performed during CMD-monitoring and defined as perilesional in the presence of a focal hypodense or hyperdense lesion within a 1-cm radius of the gold tip of the CMD-probe, or otherwise as normal-appearing brain tissue. RESULTS: Probe location was detected in normal-appearing brain tissue on 53/143 (37%) and in perilesional location on 90/143 (63%) CT scans. In the perilesional area, CMD-glucose levels were lower (p = 0.003), whereas CMD-lactate (p = 0.002), CMD-lactate-to-pyruvate-ratio (LPR; p < 0.001), CMD-glutamate (p = 0.002), and CMD-glycerol levels (p < 0.001) were higher. Neuroglucopenia (CMD-glucose < 0.7 mmol/l, p = 0.002), metabolic distress (p = 0.002), and mitochondrial dysfunction (p = 0.005) were more common in perilesional compared to normal-appearing brain tissue. Development of new lesions in the proximity of the CMD-probe (n = 13) was associated with a decrease in CMD-glucose levels, evidence of neuroglucopenia, metabolic distress, as well as increasing CMD-glutamate and CMD-glycerol levels. Neuroglucopenia was associated with poor outcome independent of probe location, whereas elevated CMD-lactate, CMD-LPR, CMD-glutamate, and CMD-glycerol levels were only predictive of poor outcome in normal-appearing brain tissue. CONCLUSIONS: Focal brain lesions significantly impact on concentrations of brain metabolites assessed by CMD. With the exception of CMD-glucose, the prognostic value of CMD-derived parameters seems to be higher when assessed in normal-appearing brain tissue. CMD was sensitive to detect the development of new focal lesions in vicinity to the neuromonitoring probe. Probe location should be described in the research reporting brain metabolic changes measured by CMD and integrated in statistical models.


Asunto(s)
Encéfalo/metabolismo , Microdiálisis/métodos , Hemorragia Subaracnoidea/metabolismo , Anciano , Aneurisma Roto/complicaciones , Aneurisma Roto/terapia , Encéfalo/diagnóstico por imagen , Edema Encefálico/etiología , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/etiología , Isquemia Encefálica/metabolismo , Estudios de Cohortes , Femenino , Glucosa/análisis , Glucosa/metabolismo , Ácido Glutámico/análisis , Ácido Glutámico/metabolismo , Glicerol/análisis , Glicerol/metabolismo , Humanos , Hidrocefalia/etiología , Hidrocefalia/cirugía , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/terapia , Ácido Láctico/análisis , Ácido Láctico/metabolismo , Masculino , Microdiálisis/instrumentación , Persona de Mediana Edad , Mitocondrias/metabolismo , Monitoreo Fisiológico , Estudios Prospectivos , Ácido Pirúvico/análisis , Ácido Pirúvico/metabolismo , Estudios Retrospectivos , Estrés Fisiológico , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/terapia
20.
Int J Mol Sci ; 21(12)2020 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-32545883

RESUMEN

We present a case study report into nutritional competition between Trichoderma spp. isolated from wild raspberries and fungal phytopathogenic isolates (Colletotrichum sp., Botrytis sp., Verticillium sp. and Phytophthora sp.), which infect soft fruit ecological plantations. The competition was evaluated on the basis of nutritional potentiates. Namely, these were consumption and growth, calculated on the basis of substrate utilization located on Biolog® Filamentous Fungi (FF) plates. The niche size, total niche overlap and Trichoderma spp. competitiveness indices along with the occurrence of a stressful metabolic situation towards substrates highlighted the unfolding step-by-step approach. Therefore, the Trichoderma spp. and pathogen niche characteristics were provided. As a result, the substrates in the presence of which Trichoderma spp. nutritionally outcompete pathogens were denoted. These were adonitol, D-arabitol, i-erythritol, glycerol, D-mannitol and D-sorbitol. These substrates may serve as additives in biopreparations of Trichoderma spp. dedicated to plantations contaminated by phytopathogens of the genera Colletotrichum sp., Botrytis sp., Verticillium sp. and Phytophthora sp.


Asunto(s)
Hongos Mitospóricos/fisiología , Phytophthora/crecimiento & desarrollo , Rubus/crecimiento & desarrollo , Trichoderma/fisiología , Botrytis/crecimiento & desarrollo , Colletotrichum/crecimiento & desarrollo , Eritritol/análisis , Frutas/crecimiento & desarrollo , Frutas/microbiología , Glicerol/análisis , Manitol/análisis , Ribitol/análisis , Rubus/microbiología , Saccharomycetales/crecimiento & desarrollo , Microbiología del Suelo , Sorbitol/análisis , Alcoholes del Azúcar/análisis
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