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1.
Rapid Commun Mass Spectrom ; 38(18): e9862, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39005224

RESUMEN

RATIONALE: The detection of organic nitrogen compounds in exhaled breath is expected to provide an early warning of diseases such as kidney disease. Detecting these trace disease markers in exhaled breath with complex composition and high moisture content is a challenge. Surface ionization (SI) shows a highly selective ionization of organic nitrogen compounds, and it is a good candidate for breath analysis combined with ion mobility spectrometry (IMS). METHODS: A stepwise SI method of low-temperature adsorption/high-temperature ionization was proposed, and trimethylamine (TMA) was detected when combined with an ion mobility spectrometer. TMA at different concentrations and humidity levels and spiked in human breath was detected to evaluate the method's properties. RESULTS: TMA with concentrations from 2 to 200 ppb was detected. The peak intensity of the TMA characteristic ions was linearly related to the "e" exponent of the concentration with a curve fit of 0.996. A standard deviation of less than 0.306% was obtained with 10 replicate analyses of 10 ppb TMA. The signal intensity difference between dry and wet (relative humidity > 93%) TMA samples is only 2.7%, and the recovery rate of the sample was 106.819%. CONCLUSIONS: SI-IMS based on the stepwise SI method has the advantages of low ionization temperature, high detection sensitivity, strong resistance to humidity interference, and good repeatability. It is a promising method for detecting organic nitrogen compounds in exhaled breath.


Asunto(s)
Pruebas Respiratorias , Espectrometría de Movilidad Iónica , Metilaminas , Espectrometría de Movilidad Iónica/métodos , Humanos , Pruebas Respiratorias/métodos , Metilaminas/análisis , Humedad , Iones/análisis , Iones/química
2.
J Agric Food Chem ; 72(26): 14498-14520, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38885200

RESUMEN

Trimethylamine N-oxide (TMAO), a characteristic nonprotein nitrogen compound, is widely present in seafood, which exhibits osmoregulatory effects for marine organisms in vivo and plays an important role in aquaculture and aquatic product preservation. However, much attention has been focused on the negative effect of TMAO since it has recently emerged as a putative promoter of chronic diseases. To get full knowledge and maximize our ability to balance the positive and negative aspects of TMAO, in this review, we comprehensively discuss the TMAO in aquatic products from the aspects of physiological functions for marine organisms, flavor, quality, the conversion of precursors, the influences on human health, and the seafood ingredients interaction consideration. Though the circulating TMAO level is inevitably enhanced after seafood consumption, dietary seafood still exhibits beneficial health effects and may provide nutraceuticals to balance the possible adverse effects of TMAO.


Asunto(s)
Metilaminas , Alimentos Marinos , Metilaminas/análisis , Metilaminas/metabolismo , Humanos , Animales , Alimentos Marinos/análisis , Organismos Acuáticos/química , Peces
3.
Artículo en Inglés | MEDLINE | ID: mdl-38936270

RESUMEN

BACKGROUND: Due to the close correlation between choline, L-carnitine, betaine and their intestinal microbial metabolites, including trimethylamine (TMA) and trimethylamine N-oxide (TMAO), and creatinine, there has been an increasing interest in the study of these compounds in vivo. METHODS: In this study, a rapid stable isotope dilution (SID)-UHPLC-MS/MS method was developed for the simultaneous determination of choline, L-carnitine, betaine, TMA, TMAO and creatinine in plasma, liver and feces of rats. The method was validated using quality control (QC) samples spiked at low, medium and high levels. Second, we applied the method to quantify the effects of Rosa Roxburghii Tratt juice (RRTJ) on plasma, liver, and fecal levels of choline, L-carnitine, betaine, TMA, TMAO, and creatinine in high-fat diet-induced hyperlipidemic rats, demonstrating the utility of the method. RESULTS: The limits of detection (LOD) were 0.04-0.027 µM and the limits of quantification (LOQ) were 0.009-0.094 µM. The linear ranges for each metabolite in plasma were choline1.50-96 µM; L-carnitine: 2-128 µM; betaine: 3-192 µM; TMA: 0.01-40.96 µM; TMAO: 0.06-61.44 µM and creatinine: 1-64 µM (R2 ≥ 0.9954). The linear ranges for each metabolite in liver were Choline: 12-768 µM; L-carnitine: 1.5-96 µM; betaine: 10-640 µM; TMA: 0.5-32 µM; TMAO: 0.02-81.92 µM and creatinine: 0.2-204.8 µM (R2 ≥ 0.9938). The linear ranges for each metabolite in feces were choline: 1.5-96 µM; L-carnitine: 0.01-40.96 µM; Betaine: 1.5-96 µM; TMA: 1-64 µM; TMAO: 0.02-81.92 µM and Creatinine: 0.02-81.92 µM (R2 ≥ 0.998). The intra-day and inter-day coefficients of variation were < 8 % for all analytes. The samples were stabilized after multiple freeze-thaw cycles (3 freeze-thaw cycles), 24 h at room temperature, 24 h at 4 °C and 20 days at -80 °C. The samples were stable. The average recovery was 89 %-99 %. This method was used to quantify TMAO and its related metabolites and creatinine levels in hyperlipidemic rats. The results showed that high-fat diet led to the disorder of TMAO and its related metabolites and creatinine in rats, which was effectively improved after the intervention of Rosa Roxburghii Tratt juice(RRTJ). CONCLUSIONS: A method for the determination of choline, L-carnitine, betaine, TMA, TMAO and creatinine in plasma, liver and feces samples was established, which is simple, time-saving, high precision, accuracy and recovery.


Asunto(s)
Betaína , Carnitina , Colina , Creatinina , Heces , Hiperlipidemias , Límite de Detección , Hígado , Metilaminas , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem , Animales , Ratas , Metilaminas/sangre , Metilaminas/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Heces/química , Colina/sangre , Colina/análisis , Colina/metabolismo , Carnitina/sangre , Carnitina/análisis , Carnitina/metabolismo , Masculino , Hígado/metabolismo , Hígado/química , Creatinina/sangre , Creatinina/análisis , Hiperlipidemias/metabolismo , Hiperlipidemias/sangre , Betaína/sangre , Betaína/análisis , Modelos Lineales , Reproducibilidad de los Resultados , Jugos de Frutas y Vegetales/análisis
4.
ACS Sens ; 9(6): 3262-3271, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38809959

RESUMEN

As trimethylamine (TMA) is widely used in agriculture and industry, inhalation of TMA can cause very serious negative effects on human health. However, most of the current gas sensors for detecting TMA are commonly performed at high temperatures and cannot meet market needs. Inspired by this, we prepared imine covalent organic frameworks (TB-COF) synthesized from two monomers, 1,3,5-tris(4-aminophenyl)benzene (TAPB) and 1,3,5-benzotricarboxaldehyde (BTCA), using acetic acid as a catalyst at room temperature. Based on this, three sensors were prepared for gas sensitivity testing, namely, TA, BT, and TB-COF sensors. The three sensors were tested for 15 different gases at room temperature. From the whole gas sensitivity data, the TB-COF sensor made by compositing TA and BT has a higher sensitivity (6845.9%) to TMA at 500 ppm, which is 6.1 and 5.4 times higher than the response of TA and BT sensors, respectively. The TB-COF sensor adsorbs and desorbs TMA in a controlled 23 s cycle with a low detection limit of 28.6 ppb. This result indicates that TB-COF prepared at room temperature can be used as a gas-sensitive sensing material for real-time monitoring of TMA. The gas sensing results demonstrate the great potential of COFs for sensor development and application and provide ideas for further development of COFs-based gas sensors.


Asunto(s)
Iminas , Estructuras Metalorgánicas , Metilaminas , Metilaminas/análisis , Metilaminas/química , Iminas/química , Estructuras Metalorgánicas/química , Límite de Detección , Gases/química , Gases/análisis
5.
Food Chem ; 448: 139078, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38527403

RESUMEN

A fluorescent sensor array (FSA) combined with deep learning (DL) techniques was developed for meat freshness real-time monitoring from development to deployment. The array was made up of copper metal nanoclusters (CuNCs) and fluorescent dyes, having a good ability in the quantitative and qualitative detection of ammonia, dimethylamine, and trimethylamine gases with a low limit of detection (as low as 131.56 ppb) in range of 5 âˆ¼ 1000 ppm and visually monitoring the freshness of various meats stored at 4 °C. Moreover, SqueezeNet was applied to automatically identify the fresh level of meat based on FSA images with high accuracy (98.17 %) and further deployed in various production environments such as personal computers, mobile devices, and websites by using open neural network exchange (ONNX) technique. The entire meat freshness recognition process only takes 5 âˆ¼ 7 s. Furthermore, gradient-weighted class activation mapping (Grad-CAM) and uniform manifold approximation and projection (UMAP) explanatory algorithms were used to improve the interpretability and transparency of SqueezeNet. Thus, this study shows a new idea for FSA assisted with DL in meat freshness intelligent monitoring from development to deployment.


Asunto(s)
Aprendizaje Profundo , Carne , Animales , Carne/análisis , Colorantes Fluorescentes/química , Metilaminas/análisis , Metilaminas/química , Amoníaco/análisis , Cobre/análisis , Cobre/química , Porcinos , Almacenamiento de Alimentos
6.
Mar Pollut Bull ; 197: 115706, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37951126

RESUMEN

Trimethylamine N-oxide (TMAO) is widely present in marine animals. However, the characteristics of TMAO content in different classes of marine animals are insufficiently understood. In this study, the TMAO content in 79 marine animals (48 species, 7 classes) collected in the coastal and offshore areas of China during year 2019-2022 was analysed. The results showed that the TMAO content of the total samples varied from 0 to 139.19 mmol kg-1. The TMAO content in the classes Bivalvia, Gastropoda, Polychaeta and Holothuroidea varied from 0.06 ± 0.09 to 0.38 ± 0.63 mmol kg-1, but it varied from 30.20 ± 24.20 to 75.90 ± 38.59 mmol kg-1 in the classes Crustacea, Cephalopoda, and Osteichthyes. The TMAO content in the latter 3 classes was 2-3 orders of magnitude higher than that of the former 4 classes. It was inferred that the significant difference was related to the food sources or physiological metabolic mechanisms of different classes.


Asunto(s)
Peces , Metilaminas , Animales , Metilaminas/análisis , Metilaminas/metabolismo , Peces/metabolismo , China
7.
Food Chem ; 424: 136475, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37269633

RESUMEN

In this work, two sensitive droplet-based luminescent assays with smartphone readout for the determination of trimethylamine nitrogen (TMA-N) and total volatile basic nitrogen (TVB-N) are reported. Both assays exploit the luminescence quenching of copper nanoclusters (CuNCs) produced when exposed to volatile nitrogen bases. In addition, hydrophobic-based cellulose substrates demonstrated their suitability as holders for both in-drop volatile enrichment and subsequent smartphone-based digitization of the enriched colloidal solution of CuNCs. Under optimal conditions, enrichment factors of 181 and 153 were obtained with the reported assays for TMA-N and TVB-N, respectively, leading to methodological LODs of 0.11 mg/100 g and 0.27 mg/100 g for TMA-N and TVB-N, respectively. The repeatability, expressed as RSD, was 5.2% and 5.6% for TMA-N and TVB-N, respectively (N = 8). The reported luminescent assays were successfully applied to the analysis of fish samples, showing statistically comparable results to those obtained with the reference methods of analysis.


Asunto(s)
Luminiscencia , Teléfono Inteligente , Animales , Metilaminas/análisis , Peces , Nitrógeno/análisis
8.
Anal Chim Acta ; 1241: 340707, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36657869

RESUMEN

This review provides a critical assessment of knowledge regarding the determination of volatile, low molecular weight amines, and particularly methylamines, in marine aquatic; systems. It provides context for the motivation to determine methylamines in the marine aquatic environment and the analytical challenges associated with their measurement.While sensitive analytical methods have been reported in recent decades, they have not been adopted by the oceanographic community to investigate methylamines' biogeochemistry and advance understanding of these analytes to the degree achieved for other marine volatiles. Gas chromatography, high performance liquid chromatography, ion chromatography and infusion-mass spectrometry techniques are discussed and critically determined, alongside offline and online preconcentration steps. Interest in the marine occurrence and cycling of methylamines has increased within the last 10-15 years, due to their potential role in climate regulation. As such, the need for robust, reproducible methods to elucidate biogeochemical cycles for nitrogen and populate marine models is apparent. Recommendations are made as to what equipment would be most suitable for future research in this area.


Asunto(s)
Aminas , Metilaminas , Aminas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Metilaminas/análisis , Espectrometría de Masas , Nitrógeno
9.
Forensic Sci Int ; 337: 111366, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35728413

RESUMEN

On the analysis of cannabidiol (CBD) e-liquid by gas chromatography-mass spectrometry, we experienced suspected thermal decomposition of CBD to Δ9-tetrahydrocannabinol (Δ9-THC). To clarify the factors involved in the decomposition, we evaluated the effects of the injection methods (splitless or split), injector temperatures (250, 225, 200, and 180 °C), and liner conditions (new liner or used liner) on the CBD decomposition. We also examined whether addition of methylamine to the dissolving solvent (methanol) inhibited the decomposition. Decomposition was not observed under split mode. However, under splitless mode, we observed that decomposition was promoted with the use of used liner and by high injector temperatures, and addition of methylamine to the dissolving solvent also suppressed the decomposition. Split injection was effective for preventing the decomposition; however, splitless injection enables detection of lower-concentrated Δ9-THC in CBD products than split injection. To balance sensitivity of Δ9-THC and inhibition of the thermal decomposition under splitless mode, we recommend using new liner for the analysis, addition of methylamine to the dissolving solvent, and maintenance of the injector temperature at 200 °C.


Asunto(s)
Cannabidiol , Dronabinol , Cannabidiol/química , Dronabinol/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Metilaminas/análisis , Solventes/análisis
10.
Environ Sci Technol ; 56(9): 5430-5439, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35435670

RESUMEN

Alkaline gases such as NH3 and amines play important roles in neutralizing acidic particles in the atmosphere. Here, two common gaseous amines (dimethylamine (DMA) and trimethylamine (TMA)), NH3, and their corresponding ions in PM2.5 were measured semicontinuously using an ambient ion monitor-ion chromatography (AIM-IC) system in marine air during a round-trip cruise of approximately 4000 km along the coastline of eastern China. The concentrations of particulate DMA, detected as DMAH+, varied from <4 to 100 ng m-3 and generally decreased with increasing atmospheric NH3 concentrations. Combining observations with thermodynamic equilibrium calculations using the extended aerosol inorganics model (E-AIM) indicated that the competitive uptake of DMA against NH3 on acidic aerosols generally followed thermodynamic equilibria and appeared to be sensitive to DMA/NH3 molar ratios, resulting in molar ratios of DMAH+ to DMA + DMAH+ of 0.31 ± 0.16 (average ± standard deviation) at atmospheric NH3 concentrations over 1.8 µg m-3 (with a corresponding DMA/NH3 ratio of (1.8 ± 1.0) × 10-3), 0.80 ± 0.15 at atmospheric NH3 concentrations below 0.3 µg m-3 (with a corresponding DMA/NH3 ratio of (1.3 ± 0.6) × 10-2), and 0.56 ± 0.19 in the remaining cases. Particulate TMA concentrations, detected as TMAH+, ranged from <2 to 21 ng m-3 and decreased with increasing concentrations of atmospheric NH3. However, TMAH+ was depleted concurrently with the formation of NH4NO3 under low concentrations of atmospheric NH3, contradictory to the calculated increase in the equilibrated concentration of TMAH+ by the E-AIM.


Asunto(s)
Contaminantes Atmosféricos , Amoníaco , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Atmósfera , Dimetilaminas/análisis , Monitoreo del Ambiente , Gases/química , Metilaminas/análisis , Material Particulado/análisis
11.
J Microbiol Biotechnol ; 31(12): 1684-1691, 2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-34961752

RESUMEN

In this study, the physicochemical changes related to fishy smell were determined by storing high hydrostatic pressure (HHP)-treated mackerel (Scomber japonicus) meat in a refrigerator for 20 days. The inhibition of crude urease activity from Vibrio parahaemolyticus using HHP treatment was also investigated. The mackerel meat storage experiment demonstrated that production of trimethylamine (TMA) and volatile basic nitrogen (VBN), the main components of fishy smell, was significantly reduced on the 20th day of storage after the HHP treatment compared to the untreated mackerels. The results demonstrated that the increased ammonia nitrogen rates in the 2000, 3000, and 4000 bar, HHP-treated groups decreased by 23.8%, 23.8%, and 31.0%, respectively, compared to the untreated groups. The enzyme activity of crude urease was significantly reduced in the HHP-treated group compared to that in the untreated group. Measurement of the volatile organic compounds (VOCs) in mackerel meat during storage indicated that the content of ethanol, 2-butanone, 3-methylbutanal, and trans-2-pentenal, which are known to cause off-flavor due to spoilage, were significantly reduced by HHP treatment. Collectively, our results suggested that HHP treatment would be useful for inhibiting the activity of urease, thereby reducing the fishy smells from fish and shellfish.


Asunto(s)
Almacenamiento de Alimentos/métodos , Perciformes , Alimentos Marinos/análisis , Ureasa/antagonistas & inhibidores , Animales , Microbiología de Alimentos , Presión Hidrostática , Metilaminas/análisis , Perciformes/microbiología , Alimentos Marinos/microbiología , Olfato , Gusto , Vibrio parahaemolyticus/enzimología , Compuestos Orgánicos Volátiles/análisis
12.
PLoS One ; 16(10): e0258396, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34644349

RESUMEN

We described, for the first time, a case of predation of a non-arthropod species by a dung beetle species. Canthon chalybaeus Blanchard, 1843 kills healthy individuals of the terrestrial snail Bulimulus apodemetes (D'Orbigny, 1835) showing an evident pattern of physical aggressiveness in the attacks using the dentate clypeus and the anterior tibiae. The description of this predatory behaviour was complemented with the analysis of the chemical secretions of the pygidial glands of C. chalybaeus, highlighting those main chemical compounds that, due to their potential toxicity, could contribute to death of the snail. We observed a high frequency of predatory interactions reinforcing the idea that predation in dung beetles is not accidental and although it is opportunistic it involves a series of behavioural sophistications that suggest an evolutionary pattern within Deltochilini that should not only be better studied from a behavioural point of view but also phylogenetically.


Asunto(s)
Escarabajos/fisiología , Conducta Predatoria , Caracoles/fisiología , Animales , Glándulas Exocrinas/química , Glándulas Exocrinas/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Indoles/análisis , Indoles/aislamiento & purificación , Metilaminas/análisis , Metilaminas/aislamiento & purificación
13.
Biosensors (Basel) ; 11(9)2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34562929

RESUMEN

The gut microbiota plays a critical role in chronic kidney disease (CKD) and hypertension. Trimethylamine-N-oxide (TMAO) and trimethylamine (TMA) are gut microbiota-derived metabolites, and both are known uraemic toxins that are implicated in CKD, atherosclerosis, colorectal cancer and cardiovascular risk. Therefore, the detection and quantification of TMAO, which is a metabolite from gut microbes, are important for the diagnosis of diseases such as atherosclerosis, thrombosis and colorectal cancer. In this study, a new "colour-switch" method that is based on the combination of a plasma separation pad/absorption pad and polyallylamine hydrochloride-capped manganese dioxide (PAH@MnO2) nanozyme was developed for the direct quantitative detection of TMAO in whole blood without blood sample pretreatment. As a proof of concept, a limit of quantitation (LOQ) of less than 6.7 µM for TMAO was obtained with a wide linear quantification range from 15.6 to 500 µM through quantitative analysis, thereby suggesting potential clinical applications in blood TMAO monitoring for CKD patients.


Asunto(s)
Microbioma Gastrointestinal , Metilaminas/análisis , Aterosclerosis , Humanos , Compuestos de Manganeso , Óxidos/análisis , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/prevención & control
14.
Food Funct ; 12(20): 9932-9946, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34492674

RESUMEN

Atherosclerosis is the leading cause of cardiovascular diseases worldwide. Trimethylamine N-oxide (TMAO), a metabolite of intestinal flora from dietary quaternary amines, has been shown to be closely related to the development of atherosclerosis. Previous studies have shown that Enterobacter aerogenes ZDY01 significantly reduces the serum levels of TMAO and cecal trimethylamine (TMA) in Balb/c mice; however, its role in the inhibition of choline-induced atherosclerosis in ApoE-/- mice remains unclear. Here, we demonstrated that E. aerogenes ZDY01 inhibited choline-induced atherosclerosis in ApoE-/- mice fed with 1.3% choline by reducing cecal TMA and modulating CDCA-FXR/FGF15 axis. We observed that E. aerogenes ZDY01 decreased the cecal TMA and serum TMAO levels by utilizing cecal TMA as a nutrient, not by changing the expression of hepatic FMO3 and the composition of gut microbiota. Furthermore, E. aerogenes ZDY01 enhanced the expression of bile acid transporters and reduced the cecal CDCA levels, thereby attenuating the FXR/FGF15 pathway, upregulating the expression of Cyp7a1, promoting reverse cholesterol transport. Taken together, E. aerogenes ZDY01 attenuated choline-induced atherosclerosis in ApoE-/- mice by decreasing cecal TMA and promoting reverse cholesterol transport, implying that E. aerogenes ZDY01 treatment might have therapeutic potential in atherosclerosis.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Proteínas de Ciclo Celular/metabolismo , Enterobacter aerogenes , Factores de Crecimiento de Fibroblastos/metabolismo , Probióticos/farmacología , Animales , Aterosclerosis/metabolismo , Aterosclerosis/microbiología , Ciego/metabolismo , Colesterol 7-alfa-Hidroxilasa/metabolismo , Colina/efectos adversos , Dieta/métodos , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Metilaminas/análisis , Metilaminas/sangre , Ratones , Ratones Noqueados para ApoE , Proteínas de Unión al ARN/metabolismo
15.
Sci Rep ; 11(1): 14680, 2021 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-34282162

RESUMEN

Endoplasmic reticulum (ER) stress is a cellular state that results from the overload of unfolded/misfolded protein in the ER that, if not resolved properly, can lead to cell death. Both acute lung infections and chronic lung diseases have been found related to ER stress. Yet no study has been presented integrating metabolomic and transcriptomic data from total lung in interpreting the pathogenic state of ER stress. Total mouse lungs were used to perform LC-MS and RNA sequencing in relevance to ER stress. Untargeted metabolomics revealed 16 metabolites of aberrant levels with statistical significance while transcriptomics revealed 1593 genes abnormally expressed. Enrichment results demonstrated the injury ER stress inflicted upon lung through the alteration of multiple critical pathways involving energy expenditure, signal transduction, and redox homeostasis. Ultimately, we have presented p-cresol sulfate (PCS) and trimethylamine N-oxide (TMAO) as two potential ER stress biomarkers. Glutathione metabolism stood out in both omics as a notably altered pathway that believed to take important roles in maintaining the redox homeostasis in the cells critical for the development and relief of ER stress, in consistence with the existing reports.


Asunto(s)
Cresoles/metabolismo , Estrés del Retículo Endoplásmico/fisiología , Glutatión/metabolismo , Lesión Pulmonar/diagnóstico , Metilaminas/metabolismo , Ésteres del Ácido Sulfúrico/metabolismo , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Cresoles/análisis , Estrés del Retículo Endoplásmico/genética , Perfilación de la Expresión Génica/métodos , Pulmón/química , Pulmón/metabolismo , Pulmón/patología , Lesión Pulmonar/genética , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Masculino , Metabolómica/métodos , Metilaminas/análisis , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo/genética , Estrés Oxidativo/fisiología , Ésteres del Ácido Sulfúrico/análisis , Respuesta de Proteína Desplegada/genética , Respuesta de Proteína Desplegada/fisiología
16.
Anal Bioanal Chem ; 413(21): 5349-5360, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34258650

RESUMEN

Trimethylamine-N-oxide (TMAO), a microbiome-derived metabolite from the metabolism of choline, betaine, and carnitines, is associated to adverse cardiovascular outcomes. A method suitable for routine quantification of TMAO and its precursors (trimethylamine (TMA), choline, betaine, creatinine, and propionyl-, acetyl-, and L-carnitine) in clinical and food samples has been developed based on LC-MS. TMA was successfully derivatized using iodoacetonitrile, and no cross-reactions with TMAO or the other methylamines were detected. Extraction from clinical samples (plasma and urine) was performed after protein precipitation using acetonitrile:methanol. For food samples (meatballs and eggs), water extraction was shown to be sufficient, but acid hydrolysis was required to release bound choline before extraction. Baseline separation of the methylamines was achieved using a neutral HILIC column and a mobile phase consisting of 25 mmol/L ammonium formate in water:ACN (30:70). Quantification was performed by MS using external calibration and isotopic labelled internal standards. The assay proved suitable for both clinical and food samples and was linear from ≈ 0.1 up to 200 µmol/L for all methylamines except for TMA and TMAO, which were linear up to 100 µmol/L. Recoveries were 91-107% in clinical samples and 76-98% in food samples. The interday (n=8, four duplicate analysis) CVs were below 9% for all metabolites in clinical and food samples. The method was applied successfully to determine the methylamine concentrations in plasma and urine from the subjects participating in an intervention trial (n=10) to determine the effect of animal food ingestion on methylamine concentrations.


Asunto(s)
Betaína/análisis , Carnitina/análisis , Colina/análisis , Creatinina/análisis , Metilaminas/análisis , Betaína/sangre , Betaína/orina , Carnitina/análogos & derivados , Carnitina/sangre , Carnitina/orina , Colina/sangre , Colina/orina , Cromatografía Liquida/métodos , Creatinina/sangre , Creatinina/orina , Femenino , Análisis de los Alimentos/métodos , Humanos , Límite de Detección , Masculino , Metilaminas/sangre , Metilaminas/orina , Persona de Mediana Edad , Espectrometría de Masas en Tándem/métodos
17.
Molecules ; 26(5)2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33801417

RESUMEN

Trimethylamine N-oxide (TMAO), as a gut-derived metabolite, has been found to be associated with enhanced risk for atherosclerosis and cardiovascular disease. We presented a method for targeted profiling of TMAO and betaine in serum and food samples based on a combination of one-step sample pretreatment and proton nuclear magnetic resonance spectroscopy. The key step included a processing of sample preparation using a selective solid-phase extraction column for retention of basic metabolites. Proton signals at δ 3.29 and δ 3.28 were employed to quantify TMAO and betaine, respectively. The developed method was examined with acceptable linear relationship, precision, stability, repeatability, and accuracy. It was successfully applied to detect serum levels of TMAO and betaine in TMAO-fed mice and high-fructose-fed rats and also used to determine the contents of TMAO and betaine in several kinds of food, such as fish, pork, milk, and egg yolk.


Asunto(s)
Betaína/análisis , Análisis de los Alimentos/métodos , Metabolómica/métodos , Metilaminas/análisis , Óxidos/química , Animales , Betaína/sangre , Betaína/metabolismo , Femenino , Masculino , Metilaminas/sangre , Metilaminas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Wistar
18.
Biosensors (Basel) ; 11(4)2021 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-33801724

RESUMEN

An amperometric trimethylamine N-oxide (TMAO) biosensor is reported, where TMAO reductase (TorA) and glucose oxidase (GOD) and catalase (Cat) were immobilized on the electrode surface, enabling measurements of mediated enzymatic TMAO reduction at low potential under ambient air conditions. The oxygen anti-interference membrane composed of GOD, Cat and polyvinyl alcohol (PVA) hydrogel, together with glucose concentration, was optimized until the O2 reduction current of a Clark-type electrode was completely suppressed for at least 3 h. For the preparation of the TMAO biosensor, Escherichia coli TorA was purified under anaerobic conditions and immobilized on the surface of a carbon electrode and covered by the optimized O2 scavenging membrane. The TMAO sensor operates at a potential of -0.8 V vs. Ag/AgCl (1 M KCl), where the reduction of methylviologen (MV) is recorded. The sensor signal depends linearly on TMAO concentrations between 2 µM and 15 mM, with a sensitivity of 2.75 ± 1.7 µA/mM. The developed biosensor is characterized by a response time of about 33 s and an operational stability over 3 weeks. Furthermore, measurements of TMAO concentration were performed in 10% human serum, where the lowest detectable concentration is of 10 µM TMAO.


Asunto(s)
Técnicas Biosensibles , Metilaminas/análisis , Electrodos , Escherichia coli , Glucosa Oxidasa , Humanos , Oxígeno
19.
PLoS One ; 16(3): e0249187, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33765061

RESUMEN

Osteogenic endothelial progenitor cells (EPCs) contribute to impaired endothelial repair and promote coronary artery disease (CAD) and vascular calcification. Immature EPCs expressing osteocalcin (OCN) has been linked to unstable CAD; however, phenotypic regulation of OCN-expressing EPCs is not understood. We hypothesized that gut-microbiome derived pro-inflammatory substance, trimethylamine N-oxide (TMAO) might be associated with mobilization of OCN-expressing EPCs. This study aimed to investigate the association between dysbiosis, TMAO, and circulating mature and immature OCN-expressing EPCs levels in patients with and without CAD. We included 202 patients (CAD N = 88; no CAD N = 114) who underwent assessment of EPCs using flow cytometry and gut microbiome composition. Mature and immature EPCs co-staining for OCN were identified using cell surface markers as CD34+/CD133-/kinase insert domain receptor (KDR)+ and CD34-/CD133+/KDR+ cells, respectively. The number of observed operational taxonomy units (OTU), index of microbial richness, was used to identify patients with dysbiosis. The number of immature OCN-expressing EPCs were higher in patients with CAD or dysbiosis than patients without. TMAO levels were not associated with circulating levels of OCN-expressing EPCs. The relative abundance of Ruminococcus gnavus was moderately correlated with circulating levels of immature OCN-expressing EPCs, especially in diabetic patients. Gut dysbiosis was associated with increased levels of TMAO, immature OCN-expressing EPCs, and CAD. The relative abundance of Ruminococcus gnavus was correlated with immature OCN-expressing EPCs, suggesting that the harmful effects of immature OCN-expressing EPCs on CAD and potentially vascular calcification might be mediated by gut microbiome-derived systemic inflammation.


Asunto(s)
Enfermedad de la Arteria Coronaria/patología , Microbioma Gastrointestinal , Osteocalcina/metabolismo , Antígeno AC133/metabolismo , Adulto , Anciano , Antígenos CD34/metabolismo , Estudios de Casos y Controles , Células Cultivadas , Clostridiales/aislamiento & purificación , Clostridiales/fisiología , Enfermedad de la Arteria Coronaria/metabolismo , Disbiosis , Células Progenitoras Endoteliales/citología , Células Progenitoras Endoteliales/metabolismo , Femenino , Humanos , Masculino , Metilaminas/análisis , Persona de Mediana Edad , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
20.
Mikrochim Acta ; 188(3): 74, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33558967

RESUMEN

The architecture of PO43- modified 2D TiO2 nanosheets was constructed by ionic liquids (ILs)-assisted hydrothermal method. The nanosheet structure can be regulated by the addition of different amount of ionic liquid. Using the composite nanosheets  a chemoresistive gas sensor was prepared for trimethylamine (TMA) detection. Most reported TMA sensors need to be operated at a relatively high operating temperature, but in this paper, the as-synthesized PO43--modified 2D TiO2/Ti2O(PO4)2 nanosheet sensor has high response (S = 87.46), short response time (14.6 s), and good reproducibility to 100 ppm TMA gas, when the temperature is 170 °C. In contrast to the single-phase TiO2 sensor, the gas-sensing property of the composite one is obviously enhanced. Moreover, its response shows excellent linear relationship with TMA concentration from 0.2 to 500 ppm, and a detection limit of 0.2 ppm. The TMA detection mechanism was investigated by analyzing the changes of the surface adsorption oxygen content by XPS and gaseous products using gas chromatography after the sensor was in contact with TMA.


Asunto(s)
Contaminantes Atmosféricos/análisis , Líquidos Iónicos/química , Metilaminas/análisis , Nanoestructuras/química , Fosfatos/química , Titanio/química , Adsorción , Contaminantes Atmosféricos/química , Gases/análisis , Gases/química , Imidazoles/química , Límite de Detección , Metilaminas/química , Oxidación-Reducción , Oxígeno/química , Fosfatos/síntesis química , Espectroscopía de Fotoelectrones , Reproducibilidad de los Resultados , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química
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