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1.
Food Chem ; 458: 140310, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38970960

RESUMEN

Gelidium sesquipedale is valued in the Spanish agar industry, but its production generates substantial waste, often discarded despite its nutritional and bioactive content. Subcritical water extraction (SWE) at 175 °C and 50 bar for 130 min was performed on this waste after agar extraction, comparing it to conventional ethanol extraction. The SWE extract exhibited superior nutritional profile, including proteins (170.6 ± 1.0 mg/gfreeze-dried-extract), essential amino acids (18.1%), carbohydrates (148.1 ± 0.3 mg/gfreeze-dried-extract), total phenolic content (57 ± 7 mg-EqGA/gfreeze-dried-extract), and also containing Maillard reaction compounds, such as 5-hydroxymethylfurfural, furfural, 2-furanmethanol, 1-(2-furanyl)-ethanone, and 5-methyl-2-furfural, influencing color, aroma and flavor. This extract showed better antioxidant and anti-inflammatory properties than the conventional extract, and higher xanthine oxidase, tyrosinase, and acetylcholinesterase inhibition activities. Toxicological assessment on human cells indicated the safety of the SWE extract. Therefore, SWE technology offers a promising method to valorize G. sesquipedale residue, yielding a bioactive and nutrient-rich extract suitable for food and nutraceutical applications.

2.
Food Chem ; 367: 130503, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34352697

RESUMEN

The mineral contents and volatile profiles of 23 sweet cherry cultivars were determined. A total of 27 minerals were determined by ICP-MS and flame atomic absorption spectrometry, including 12 essential and 15 non-essential elements. K was the most abundant in all cultivars, while Tl was the one found in the smallest amounts. A total of 66 volatiles were identified using SPME/GC-MS, including 16 aldehydes, 23 alcohols, 6 ketones, 6 esters, 8 monoterpenes, 3 norisoprenoids, 2 hydrocarbons and 2 acids. Benzaldehyde, hexanal, nonanal, benzyl alcohol, (E)-2-hexen-1-ol, 1-hexanol, (Z)-2-hexen-1-ol, 2-ethyl-1-hexanol, linalool, α-terpineol and α-ionone were the major ones. Qualitative and quantitative differences were observed among the cultivars, which influenced nutritional potential and aroma. Cherries from Fundão region contain high concentrations of phytochemicals and nutritional components. 4-84, Burlat and Celeste might be considered some of the most interesting cultivars, since they are rich in essential minerals and present high diversity in volatiles.


Asunto(s)
Administración Financiera , Prunus avium , Compuestos Orgánicos Volátiles , Odorantes/análisis , Portugal , Microextracción en Fase Sólida
3.
Metabolites ; 10(5)2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32349455

RESUMEN

The identification of noninvasive biomarkers able to detect renal cell carcinoma (RCC) at an early stage remains an unmet clinical need. The recognition that altered metabolism is a core hallmark of cancer boosted metabolomic studies focused in the search for cancer biomarkers. The present work aims to evaluate the performance of the volatile metabolites present in the extracellular medium to discriminate RCC cell lines with distinct histological subtypes (clear cell and papillary) and metastatic potential from non-tumorigenic renal cells. Hence, volatile organic compounds (VOCs) and volatile carbonyl compounds (VCCs) were extracted by headspace solid-phase microextraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). Multivariate and univariate analysis unveiled a panel of metabolites responsible for the separation between groups, mostly belonging to ketones, alcohols, alkanes and aldehydes classes. Some metabolites were found similarly altered for all RCC cell lines compared to non-tumorigenic cells, namely 2-ethylhexanol, tetradecane, formaldehyde, acetone (increased) and cyclohexanone and acetaldehyde (decreased). Furthermore, significantly altered levels of cyclohexanol, decanal, decane, dodecane and 4-methylbenzaldehyde were observed in all metastatic RCC cell lines when compared with the non-metastatic ones. Moreover, some alterations in the volatile composition were also observed between RCC histological subtypes. Overall, our results demonstrate the potential of volatile profiling for identification of noninvasive candidate biomarkers for early RCC diagnosis.

4.
J Clin Pharmacol ; 60(5): 617-628, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31797395

RESUMEN

This study aimed to develop a population pharmacokinetic-pharmacodynamic (PKPD) model for propofol using data prospectively collected from a heterogeneous group of adult, elderly, and obese patients using the bispectral index (BIS) as a pharmacodynamic guide. Adult, obese (body mass index ≥35 kg/m2 ), and elderly patients (aged >65 years) were included. Propofol infusion was started at 2000 mg/h until loss of consciousness and then guided by target BIS values (40-60). Measurements of propofol plasma concentration were performed using gas chromatography. A PKPD model was developed using NONMEM. The data set contained 423 propofol concentrations and 483 897 BIS values from 60 patients (20-92 years, 42-136 kg). A 3-compartment model was used to describe the plasma concentrations of propofol. An allometric model using lean body weight calculated by the Janmahasatian formula was found to describe the data better than total body weight for all clearance parameters, V1 and V2. An age effect was found on Q2, Q3, V1, and V3. With respect to the PD model, the use of a 2-compartment model significantly improved the model fit. Age and total body weight were included as covariates in the final pharmacodynamic model. We propose a PKPD model for propofol anesthesia with acceptable performance accuracy in a heterogeneous group of adult, elderly, and obese patients. A new method to predict propofol induction dose is presented. This method and the possibility to directly change target BIS values in opposition to the assumed target effect-site concentration constitutes certain advantages to the clinical practice.

5.
Arch Toxicol ; 93(11): 3277-3290, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31494693

RESUMEN

Methylone (3,4-methylenedioxymethcathinone) is one of the most popular new psychoactive drugs worldwide. Although advertised as a safe drug, its use has been associated to several cases of liver damage. In this work, a metabolomics approach based on gas chromatography-mass spectrometry (GC-MS) combined with chemometric analyses was used to characterize the disturbances occurring in the intra- and extracellular metabolome of primary mouse hepatocytes exposed to two subtoxic concentrations (LC01 and LC10) of methylone to better understand the early hepatotoxic events. Results showed a characteristic metabolic fingerprint for methylone, where aspartate, cysteine, 2-methyl-1-pentanol, 4-methylheptane, dodecane, 2,4-dimethyl-1-heptene, 1,3-di-tert-butylbenzene, acetophenone, formaldehyde and glyoxal levels were significantly changed at both concentrations tested. Furthermore, subtoxic concentrations of methylone caused profound changes in several biochemical pathways, suggesting adaptations in energy production processes (TCA cycle, amino acids metabolism and pyruvate metabolism), cellular antioxidant defenses (glutamate, cysteine and glutathione metabolism) and hepatic enzymes (associated to hydrocarbons, alcohols, aldehydes and ketones metabolism). This metabolic response to the initial methylone challenge most probably reflects the activation of protective mechanisms to restore cellular homeostasis. Overall, this study highlights the potential of untargeted metabolomic analysis to reveal the hepatic metabolic signature of methylone at subtoxic concentrations, and also provides clues to clarify the early mechanisms underlying the toxicity triggered by this new psychoactive substance, opening a new perspective for the study of toxicity mechanisms of new xenobiotics.


Asunto(s)
Estimulantes del Sistema Nervioso Central/toxicidad , Hepatocitos/efectos de los fármacos , Metaboloma/efectos de los fármacos , Metanfetamina/análogos & derivados , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Hepatocitos/metabolismo , Hepatocitos/patología , Metabolómica , Metanfetamina/toxicidad , Ratones , Cultivo Primario de Células
6.
Toxicol Sci ; 169(2): 422-435, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30796436

RESUMEN

The widespread recreational use of synthetic cannabinoids (SCBs) represents a major public health issue, as reports of intoxications and deaths following SCB use rapidly mount up. Specifically, a direct link between SCB use and acute kidney injury (AKI) has been established, although the pathophysiologic mechanisms remain undefined. Here we assessed the in vitro nephrotoxicity of 3 commonly detected and structurally distinct SCBs-AB-FUBINACA, JWH-122, and THJ-2201-in human proximal tubule cells (HK-2), to ascertain potential similarities and/or differences regarding their nephrotoxicity signatures. We showed that 2 of the 3 SCBs tested, namely JWH-122 and THJ-2201, at in vivo relevant concentrations (1 nM-1 µM), triggered apoptotic cell death pathways, mainly through a shared mechanism involving the deregulation of mitochondrial function (ie, with mitochondrial membrane hyperpolarization and increased intracellular ATP levels), as the primary molecular signature of nephrotoxicity mechanism. Noteworthy, no SCB affected cell viability (MTT reduction, lactate dehydrogenase release, Neutral Red inclusion). Use of the cannabinoid receptor (CBR) antagonists SR141716A and SR144528, as well as HEK293T cells, which do not express CBRs, confirmed the involvement of these receptors in SCB-mediated mitochondrial membrane hyperpolarization but not on other events, suggesting an off-target action regulating SCB-induced kidney cell death. Our results further strengthen the relevance of the endocannabinoid system in maintaining mitochondrial function in kidney cells, as we demonstrate that HK-2 incubation with CBR antagonists or inhibitors of endocannabinoid biosynthesis (ie, methyl arachydonyl fluorophosphonate, tetrahydrolipstatin) alone produced deleterious effects similar to those now reported for SCBs. Overall, SCB-induced nephrotoxicity seems to be mainly regulated at the mitochondrial level, but the specific mechanisms involved require further clarification.


Asunto(s)
Apoptosis/efectos de los fármacos , Endocannabinoides/fisiología , Indazoles/toxicidad , Indoles/toxicidad , Riñón/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Naftalenos/toxicidad , Adenosina Trifosfato/análisis , Supervivencia Celular/efectos de los fármacos , Células HEK293 , Humanos , Mitocondrias/fisiología , Transducción de Señal/efectos de los fármacos
7.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1100-1101: 158-164, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30336346

RESUMEN

The enantioresolution of pentedrone and methylone was carried out at a multi-milligram scale by liquid chromatography on a Chiralpak AS® stationary phase. The excellent enantioresolution using this column allowed to collect highly pure enantiomeric fractions, achieving enantiomeric ratios higher than 98%. An overall recovery of 72% was achieved for pentedrone enantiomers and 80% for methylone. Furthermore, the absolute configuration of the enantiomers of both cathinones was determined for the first time by electronic circular dichroism (ECD) spectroscopy, with the aid of theoretical calculations, as (+)­(S) and (-)­(R)-pentedrone, and (-)­(S) and (+)­(R)­methylone.


Asunto(s)
Metanfetamina/análogos & derivados , Metilaminas/análisis , Metilaminas/química , Pentanonas/análisis , Pentanonas/química , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Metanfetamina/análisis , Metanfetamina/química , Modelos Moleculares , Estereoisomerismo
8.
Metabolomics ; 14(5): 62, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-30830384

RESUMEN

INTRODUCTION: Recent studies provide a convincing support that the presence of cancer cells in the body leads to the alteration of volatile organic compounds (VOCs) emanating from biological samples, particularly of those closely related with tumoral tissues. Thus, a great interest emerged for the study of cancer volatilome and subsequent attempts to confirm VOCs as potential diagnostic biomarkers. OBJECTIVES: The aim of this study was to determine the volatile metabolomic signature of bladder cancer (BC) cell lines and provide an in vitro proof-of-principle that VOCs emanated into the extracellular medium may discriminate BC cells from normal bladder epithelial cells. METHODS: VOCs in the culture media of three BC cell lines (Scaber, J82, 5637) and one normal bladder cell line (SV-HUC-1) were extracted by headspace-solid phase microextraction and analysed by gas chromatography-mass spectrometry (HS-SPME/GC-MS). Two different pH (pH 2 and 7) were used for VOCs extraction to infer the best pH to be used in in vitro metabolomic studies. RESULTS: Multivariate analysis revealed a panel of volatile metabolites that discriminated cancerous from normal bladder cells, at both pHs, although a higher number of discriminative VOCs was obtained at neutral pH. Most of the altered metabolites were ketones and alkanes, which were generally increased in BC compared to normal cells, and alcohols, which were significantly decreased in BC cells. Among them, three metabolites, namely 2-pentadecanone, dodecanal and γ-dodecalactone (the latter only tentatively identified), stood out as particularly important metabolites and promising volatile biomarkers for BC detection. Furthermore, our results also showed the potential of VOCs in discriminating BC cell lines according to tumour grade and histological subtype. CONCLUSIONS: We demonstrate that a GC-MS metabolomics-based approach for analysis of VOCs is a valuable strategy for identifying new and specific biomarkers that may improve BC diagnosis. Future studies should entail the validation of volatile signature found for BC cell lines in biofluids from BC patients.


Asunto(s)
Metabolómica/métodos , Neoplasias de la Vejiga Urinaria/metabolismo , Compuestos Orgánicos Volátiles/química , Biomarcadores , Línea Celular Tumoral , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Análisis Multivariante , Microextracción en Fase Sólida/métodos , Neoplasias de la Vejiga Urinaria/química , Compuestos Orgánicos Volátiles/análisis
9.
World J Microbiol Biotechnol ; 33(3): 46, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28168624

RESUMEN

In this study, the antimicrobial potential of three fungal endophytes from leaves of Olea europaea L. was evaluated and the host plant extract effect in the antimicrobial activity was examined. The volatile compounds produced by endophytes were identified by GC/MS and further correlated with the antimicrobial activity. In potato dextrose agar, both Penicillium commune and Penicillium canescens were the most effective inhibiting Gram-positive and -negative bacteria (up to 2.7-fold compared to 30 µg/mL chloramphenicol), whereas Alternaria alternata was most effective inhibiting yeasts (up to 8.0-fold compared to 25 µg/mL fluconazole). The presence of aqueous leaf extract in culture medium showed to induce or repress the antimicrobial activity, depending on the endophytic species. In the next step, various organic extracts from both A. alternata mycelium and cultured broth were prepared; being ethyl acetate extracts displayed the widest spectrum of anti-microorganisms at a minimum inhibitory concentration ≤0.095 mg/mL. The volatile composition of the fungi that displayed the highest (A. alternata) and the lowest (P. canescens) antimicrobial activity against yeasts revealed the presence of six volatiles, being the most abundant components (3-methyl-1-butanol and phenylethyl alcohol) ascribed with antimicrobial potentialities. Overall the results highlighted for the first time the antimicrobial potential of endophytic fungi from O. europaea and the possibility to be exploited for their antimicrobial agents.


Asunto(s)
Endófitos/metabolismo , Hongos/fisiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Olea/microbiología , Extractos Vegetales/farmacología , Acetatos/química , Alternaria/efectos de los fármacos , Cloranfenicol/farmacología , Fluconazol/farmacología , Pruebas de Sensibilidad Microbiana , Olea/química , Penicillium/metabolismo , Pentanoles/farmacología , Alcohol Feniletílico/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/microbiología , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/farmacología , Levaduras/efectos de los fármacos
10.
Springerplus ; 5(1): 1349, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27588242

RESUMEN

In humans, prolonged sedations with propofol or using high doses have been associated with propofol infusion syndrome. The main objective of this study was to evaluate the effects of prolonged high-dose administration of a specific propofol emulsion (Propofol Lipuro) and an improved lipid formulation (SMOFlipid) in liver mitochondrial bioenergetics and oxidative stress of rabbits, comparatively to a saline control. Twenty-one male New Zealand white rabbits were randomly allocated in three groups that were continuously treated for 20 h. Each group of seven animals received separately: NaCl 0.9 % (saline), SMOFlipid (lipid-based emulsion without propofol) and Lipuro 2 % (propofol lipid emulsion). An intravenous propofol bolus of 20 mg kg(-1) was given to the propofol Lipuro group to allow blind orotracheal intubation and mechanical ventilation. Anesthesia was maintained using infusion rates of: 20, 30, 40, 50 and 60 mg kg(-1) h(-1), according to the clinical scale of anesthetic depth and the index of consciousness values. The SMOFlipid and saline groups received the same infusion rate as the propofol Lipuro group, which were infused during 20 consecutive hours. At the end, the animals were euthanized, livers collected and mitochondria isolated by standard differential centrifugation. Mitochondrial respiration, membrane potential, swelling and oxidative stress were evaluated. Data were processed using one-way ANOVA (p < 0.05). The animals revealed a significant decrease in cardiovascular parameters showing bradycardia and severe hypotension. No statistical differences were observed when using pyruvate as substrate, however, when using succinate as respiratory substrate, significant decrease in ADP-stimulated respiration rate was observed for SMOFlipid group (p = 0.002). Lipid peroxides (p < 0.01) and protein carbonyls (p = 0.01) showed a statistically significant difference between propofol Lipuro and the SMOFlipid groups. These results suggest that lipid-based emulsions can be involved in the regulation of different pathways that ultimately lead to a decrease of state 3 mitochondrial respiration rate. The infusion of propofol Lipuro during prolonged periods, in addition to marked hypotension and hypoperfusion, also showed to have higher anti-oxidant activity and lower impairment of the mitochondrial function comparatively to the improved lipid formulation, SMOFlipid, using the rabbit as animal model.

11.
Forensic Toxicol ; 34: 372-385, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27594923

RESUMEN

Recently, great interest has been focused on synthetic cathinones since their consumption has increased exponentially. All synthetic cathinones exist as chiral molecules; the biological and/or toxicological properties of cathinones generally differ according to the enantiomers in human body. In this study, a chiral liquid chromatography method was developed to separate and determine the enantiomeric ratio of synthetic cathinones present in "legal highs" acquired in old smart shops or over the Internet. All the synthetic cathinones were efficiently enantio-separated with α and Rs ranging from 1.24 to 3.62 and from 1.24 to 10.52, respectively, using polysaccharide-based chiral stationary phases. All synthetic cathinones, with the exception of 4-methylethcathinone (4-MEC), were present in the commercialized "legal highs" in an enantiomeric proportion of 50:50. One of the studied chiral compounds was 3,4-methylenedioxypyrovalerone (MDPV), one of the most consumed cathinone derivative worldwide. Our research group has recently reported its hepatotoxicity in the racemic form. Thus, the analytical enantioresolution of the MDPV was scaled up to multi-milligram using a semi-preparative amylose tris-3,5-dimethylphenylcarbamate column (20 cm × 7.0 mm ID, 7 µm particle size). Both enantiomers were isolated with high enantiomeric purity (enantiomeric excess > 99 %). The toxicity of S-(-)-MDPV and R-(+)-MDPV was evaluated, for the first time, using primary cultures of rat hepatocytes. It was also possible to verify that MDPV enantiomers showed hepatotoxicity in a concentration-dependent manner, but displayed no enantioselective toxicity in this cell culture model.

12.
Exp Toxicol Pathol ; 68(9): 521-531, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27531257

RESUMEN

BACKGROUND: Propofol biotransformation occurs in the liver via hydroxylation by CYP450 enzymatic complex and by glucuronidation, however extra-hepatic metabolism has also been described. OBJECTIVES: To better understand the metabolic pathways involved in propofol biotransformation, the expression of CYP1A1, CYP1A2, the enzymatic and non-enzymatic antioxidant activity and the amount of propofol and its non-conjugated metabolites were investigated. METHODS: Twenty-one NewZealand rabbits were allocated into three groups continuously treated for 20h. Each group received: NaCl 0.9%, vehicle (SMOFlipid) and propofol 2% (Lipuro). At the end, liver and kidney samples were collected for histopathology and immunohistochemistry and plasma for quantification of propofol and its metabolites. RESULTS: CYP1A1 and CYP1A2 were observed in zone 1 and zone 3 regions of the liver acinus. The propofol and saline groups showed a higher expression of CYP1A1 when compared to vehicle group. Propofol significantly increased CYP1A2 expression, compared to saline. CYP1A1 and CYP1A2 immunoexpression were observed in the kidney but no differences were registered between groups. CONCLUSIONS: This suggests that propofol may act as selective inhibitor of CYP1A1 and an inducer of CYP1A2 expression in different regions of the liver. Propofol seems to have an antioxidative protective effect on liver parenchyma, comparatively to the emulsion alone. In the rabbit, extra-hepatic propofol biotransformation may also occur in the kidney.


Asunto(s)
Citocromo P-450 CYP1A1/biosíntesis , Citocromo P-450 CYP1A2/biosíntesis , Hipnóticos y Sedantes/metabolismo , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Propofol/metabolismo , Animales , Hipnóticos y Sedantes/farmacología , Inmunohistoquímica , Riñón/metabolismo , Hígado/metabolismo , Propofol/farmacología , Conejos
13.
Meat Sci ; 121: 382-389, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27449232

RESUMEN

This work describes the effect of the incorporation of 1% spent yeast extract into cooked hams. Physical/chemical/sensorial characteristics and changes during 12 and 90days storage were evaluated on control and treated cooked hams processed for 1.5, 2.0, 2.5 or 3h. Spent yeast extract addition increased hardness, chewiness, ash, protein and free amino acid content. Similar volatile profiles were obtained, although there were some quantitative differences. No advantages were observed for increased cooking time. No significant differences were observed for physical and sensorial parameters of cooked hams with spent yeast extract at 12 and 90days post production, but His, aldehydes and esters increased at the end of storage. This behaviour was similar to that observed for control hams. The higher hardness of cooked ham with 1% yeast extract was due to the stronger gel formed during cooking and was maintained during storage. This additive acts as gel stabilizer for cooked ham production and could potentially improve other processing characteristics.


Asunto(s)
Culinaria , Productos de la Carne/microbiología , Saccharomyces cerevisiae/metabolismo , Adulto , Animales , Fenómenos Químicos , Comportamiento del Consumidor , Microbiología de Alimentos , Humanos , Concentración de Iones de Hidrógeno , Persona de Mediana Edad , Análisis de Componente Principal , Porcinos , Compuestos Orgánicos Volátiles/análisis , Adulto Joven
14.
Int J Cancer ; 139(2): 256-68, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-26804544

RESUMEN

Metabolomics has recently proved to be useful in the area of biomarker discovery for cancers in which early diagnostic and prognostic biomarkers are urgently needed, as is the case of bladder cancer (BC). This article presents a comprehensive review of the literature on the metabolomic studies on BC, highlighting metabolic pathways perturbed in this disease and the altered metabolites as potential biomarkers for BC detection. Current disease model systems used in the study of BC metabolome include in vitro-cultured cancer cells, ex vivo neoplastic bladder tissues and biological fluids, mainly urine but also blood serum/plasma, from BC patients. The major advantages and drawbacks of each model system are discussed. Based on available data, it seems that BC metabolic signature is mainly characterized by alterations in metabolites related to energy metabolic pathways, particularly glycolysis, amino acid and fatty acid metabolism, known to be crucial for cell proliferation, as well as glutathione metabolism, known to be determinant in maintaining cellular redox balance. In addition, purine and pyrimidine metabolism as well as carnitine species were found to be altered in BC. Finally, it is emphasized that, despite the progress made in respect to novel biomarkers for BC diagnosis, there are still some challenges and limitations that should be addressed in future metabolomic studies to ensure their translatability to clinical practice.


Asunto(s)
Metaboloma , Metabolómica , Neoplasias de la Vejiga Urinaria/metabolismo , Animales , Biomarcadores , Técnicas de Cultivo de Célula , Humanos , Técnicas In Vitro , Redes y Vías Metabólicas , Metabolómica/métodos , Neoplasias de la Vejiga Urinaria/diagnóstico
15.
Basic Clin Pharmacol Toxicol ; 118(6): 421-31, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26551921

RESUMEN

Propofol is an anaesthetic widely used in both human beings and animals. However, the characterization of propofol pharmacokinetics (PK) is not well understood when long-term infusions are used. The main objective of this study was to explore the PK behaviour of propofol in a rabbit model during short and prolonged propofol infusions and to develop an internally validated PK model, for propofol dose individualization in the rabbit for future use. Population 1 (P1) was constituted by seven New Zealand rabbits and was used to characterize the PK profile of propofol at short infusions. Animals were anaesthetized with a bolus of 20 mg/kg, followed by an infusion rate of 50 mg/kg/hr of propofol at 1%, which was then maintained for 30 min. A second rabbit population (P2, n = 7) was sedated according to reflexes responses and Index of Consciousness values, for 20 consecutive hours using propofol 2% aiming at characterizing propofol behaviour at long-term infusions. Clinical data and blood samples were collected at specific time-points in both populations. Propofol plasma concentrations were determined by gas chromatography/ion trap mass spectrometry. The NONMEM VII software was used to evaluate the relationships between dose and plasma concentrations. A linear two-compartment model with different central compartment volume and plasma clearance (separately modelled in the two populations) was the one that best described propofol concentrations. The time course of propofol plasma concentrations was well characterized by the PK model developed, which simultaneously accounts for propofol short- and long-term infusions and can be used to optimize future PK studies in rabbits.


Asunto(s)
Anestésicos Intravenosos/farmacocinética , Modelos Biológicos , Propofol/farmacocinética , Anestésicos Intravenosos/administración & dosificación , Animales , Relación Dosis-Respuesta a Droga , Cromatografía de Gases y Espectrometría de Masas , Infusiones Intravenosas/métodos , Masculino , Propofol/administración & dosificación , Conejos
16.
Talanta ; 148: 486-93, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26653476

RESUMEN

A new and simple analytical approach consisting of an automated headspace solid-phase microextraction (HS-SPME) sampler coupled to gas chromatography-ion trap/mass spectrometry detection (GC-IT/MS) with a prior derivatization step with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was developed to detect volatile carbonyl metabolites with low molecular weights in human urine. A central composite design (CCD) was used to optimise the PFBHA concentration and extraction conditions that affect the efficiency of the SPME procedure. With a sample volume of 1 mL, optimal conditions were achieved by adding 300 mg/L of PFBHA and allowing the sample to equilibrate for 6 min at 62°C and then extracting the samples for 51 min at the same temperature, using a divinylbenzene/polydimethylsiloxane (DVB/PDMS) fibre. The method allowed the simultaneous identification and quantification of 44 carbonyl compounds consisting of aldehydes, dialdehydes, heterocyclic aldehydes and ketones. The method was validated with regards to the linearity, inter- and intra-day precision and accuracy. The detection limits ranged from 0.009 to 0.942 ng/mL, except for 4-hydroxy-2-nonenal (15 ng/mL), and the quantification limits varied from 0.029 to 1.66 ng/mL, except for butanal (2.78 ng/mL), 2-butanone (2.67 ng/mL), 4-heptanone (3.14 ng/mL) and 4-hydroxy-2-nonenal (50.0 ng/mL). The method accuracy was satisfactory, with recoveries ranging from 90 to 107%. The proof of applicability of the methodology was performed in a pilot target analysis of urine samples obtained from 18 healthy smokers and 18 healthy non-smokers (control group). Chemometric supervised analysis was performed using the volatile patterns acquired for these samples and clearly showed the potential of the volatile carbonyl profiles to discriminate urine from smoker and non-smoker subjects. 5-Methyl-2-furfural (p<0.0001), 2-methylpropanal, nonanal and 2-methylbutanal (p<0.05) were identified as potentially useful biomarkers to identify smoking habits.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/normas , Fumar/orina , Microextracción en Fase Sólida/normas , Compuestos Orgánicos Volátiles/orina , Adulto , Aldehídos/orina , Biomarcadores/orina , Femenino , Humanos , Hidroxilaminas/orina , Cetonas/orina , Masculino , Persona de Mediana Edad , Proyectos Piloto , Adulto Joven
17.
Food Chem Toxicol ; 86: 41-55, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26375431

RESUMEN

Amanita phalloides, also known as 'death cap', is one of the most poisonous mushrooms, being involved in the majority of human fatal cases of mushroom poisoning worldwide. This species contains three main groups of toxins: amatoxins, phallotoxins, and virotoxins. From these, amatoxins, especially α-amanitin, are the main responsible for the toxic effects in humans. It is recognized that α-amanitin inhibits RNA polymerase II, causing protein deficit and ultimately cell death, although other mechanisms are thought to be involved. The liver is the main target organ of toxicity, but other organs are also affected, especially the kidneys. Intoxication symptoms usually appear after a latent period and may include gastrointestinal disorders followed by jaundice, seizures, and coma, culminating in death. Therapy consists in supportive measures, gastric decontamination, drug therapy and, ultimately, liver transplantation if clinical condition worsens. The discovery of an effective antidote is still a major unsolved issue. The present paper examines the clinical toxicology of A. phalloides, providing the currently available information on the mechanisms of toxicityinvolved and on the current knowledge on the treatment prescribed against this type of mushrooms. Antidotal perspectives will be raised as to set the pace to new and improved therapy against these mushrooms.


Asunto(s)
Amanita/química , Intoxicación por Setas/patología , Péptidos Cíclicos/toxicidad , Humanos , Intoxicación por Setas/terapia , Péptidos Cíclicos/química , Conformación Proteica , Toxicocinética
18.
Bioanalysis ; 7(18): 2361-2374, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26395324

RESUMEN

This paper reviews the use of NMR metabolomics for the metabolic characterization of renal cancer. The existing challenges in the clinical management of this disease are first presented, followed by a brief introduction to the metabolomics approach, in the context of cancer research. A subsequent review of the literature on NMR metabolic studies of renal cancer reveals that the subject has been clearly underdeveloped, compared with other types of cancer, particularly regarding cultured cells and tissue analysis. NMR analysis of biofluids has focused on blood (plasma or serum) metabolomics, comprising no account of studies on human urine, in spite of its noninvasiveness and physiological proximity to the affected organs. Finally, some areas of potential future development are identified.

19.
Toxicon ; 103: 55-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26091874

RESUMEN

Mushroom poisonings occur when ingestion of wild mushrooms containing toxins takes place, placing the consumers at life-threatening risk. In the present case report, an unusual multiple poisoning with isoxazoles- and amatoxins-containing mushrooms in a context of altered mental state and poorly controlled hypertension is presented. A 68-year-old female was presented to São João hospital (Portugal) with complaints of extreme dizziness, hallucinations, vertigo and imbalance, 3 h after consuming a stew of wild mushrooms. The first observations revealed altered mental state and elevated blood pressure. The examination of cooked mushroom fragments allowed a preliminary identification of Amanita pantherina. Gas chromatography-mass spectrometry (GC-MS) showed the presence of muscimol in urine. Moreover, through high-performance liquid chromatography-ultraviolet detection (HPLC-UV) analysis of the gastric juice, the presence of α-amanitin was found, showing that amatoxins-containing mushrooms were also included in the stew. After 4 days of supportive treatment, activated charcoal, silybin and N-acetylcysteine, the patient recovered being discharged 10 days post-ingestion with no organ complications. The prompt and appropriate therapy protocol for life-threatening amatoxins toxicity probably saved the patient's life as oral absorption was decreased and also supportive care was immediately started.


Asunto(s)
Agaricales/química , Amanitinas/toxicidad , Isoxazoles/toxicidad , Acetilcisteína/uso terapéutico , Anciano , Alfa-Amanitina/análisis , Amanita/química , Amanitinas/administración & dosificación , Carbón Orgánico/uso terapéutico , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Isoxazoles/administración & dosificación , Intoxicación por Setas/diagnóstico , Intoxicación por Setas/tratamiento farmacológico , Silibina , Silimarina/uso terapéutico
20.
Mycologia ; 107(4): 679-87, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25911698

RESUMEN

Amanita phalloides is a toxic mushroom responsible for the majority of deaths occurring after mushrooms ingestion, mainly due to amatoxins. In the present study the contents and distribution of the major amatoxins and phallotoxins in different tissues of A. phalloides from two different sites of Portugal were analyzed by liquid chromatography (LC) coupled to diode array (DAD) and mass spectrometry (MS) detection. The main toxins were separated by LC and its chemical structures confirmed by MS. α-Amanitin contents in caps, stipe and volva tissues were quantified by RP-HPLC. The results show that caps have the highest content of amatoxins, whereas the volva was richest in phallotoxins. Moreover variability in the toxins composition from different geographic sites was also observed. This study provides for the first time the content of toxins in A. phalloides from Portugal.


Asunto(s)
Amanita/química , Amanitinas/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Estructura Molecular , Portugal
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