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1.
Energy Fuels ; 38(8): 7033-7048, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38654764

RESUMO

Ethanol steam reforming (ESR) over a Ni/Al2O3 catalyst prepared by reduction of a NiAl2O4 spinel is a promising alternative route to produce H2 from biomass. This work deepens into the effect of reaction conditions (450-650 °C, a steam/ethanol (S/E) ratio of 3-9, and a weight space time up to 1.3 h) and evaluates the time on stream evolution of the yields of H2, gaseous byproducts (CO, CO2, CH4, C2H4, C2H4O), and formed carbon/coke. The results are explained taking into consideration the thermodynamics, the extent of each individual reaction, and the catalyst deactivation. Up to 600 °C, the predominant intermediate in the H2 formation is C2H4 (formed by ethanol dehydration) with the preferential formation of nanostructured carbon (nanotubes/filaments) by C2H4 decomposition. The deposition of this type of carbon partially deactivates the catalyst, mainly affecting the extent of the C2H4 decomposition causing a sharp decrease in the H2 and carbon yields. Nevertheless, the catalyst reaches a pseudosteady state with an apparent constant activity for other reactions in the kinetic scheme. At 650 °C, C2H4O (formed by the ethanol dehydrogenation) is the main intermediate in the H2 formation, which is the precursor of an amorphous/turbostratic carbon (coke) formation that initially causes a rapid deactivation of the catalyst, affecting the ethanol dehydration and, to a lower extent, the reforming and water gas shift reactions. The increase in the S/E ratio favors the H2 formation, attenuates the catalyst deactivation due to the suppression of the ethanol dehydration to C2H4, and promotes the reforming, water gas shift, and carbon/coke gasification reactions. A H2 yield of 85% stable for 48 h on stream is achieved at 600 °C, with a space time of 0.1 h and an S/E ratio of 9.

2.
Handb Exp Pharmacol ; 277: 275-297, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36253553

RESUMO

For a long time, conventional medicine has analysed biomolecules to diagnose diseases. Yet, this approach has proven valid only for a limited number of metabolites and often through a bijective relationship with the disease (i.e. glucose relationship with diabetes), ultimately offering incomplete diagnostic value. Nowadays, precision medicine emerges as an option to improve the prevention and/or treatment of numerous pathologies, focusing on the molecular mechanisms, acting in a patient-specific dimension, and leveraging multiple contributing factors such as genetic, environmental, or lifestyle. Metabolomics grasps the required subcellular complexity while being sensitive to all these factors, which results in a most suitable technique for precision medicine. The aim of this chapter is to describe how NMR-based metabolomics can be integrated in the design of a precision medicine strategy, using the Precision Medicine Initiative of the Basque Country (the AKRIBEA project) as a case study. To that end, we will illustrate the procedures to be followed when conducting an NMR-based metabolomics study with a large cohort of individuals, emphasizing the critical points. The chapter will conclude with the discussion of some relevant biomedical applications.


Assuntos
Diabetes Mellitus , Medicina de Precisão , Humanos , Estudos Prospectivos , Metabolômica/métodos , Diabetes Mellitus/metabolismo , Biomarcadores
3.
Metabolites ; 12(12)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36557244

RESUMO

After SARS-CoV-2 infection, the molecular phenoreversion of the immunological response and its associated metabolic dysregulation are required for a full recovery of the patient. This process is patient-dependent due to the manifold possibilities induced by virus severity, its phylogenic evolution and the vaccination status of the population. We have here investigated the natural history of COVID-19 disease at the molecular level, characterizing the metabolic and immunological phenoreversion over time in large cohorts of hospitalized severe patients (n = 886) and non-hospitalized recovered patients that self-reported having passed the disease (n = 513). Non-hospitalized recovered patients do not show any metabolic fingerprint associated with the disease or immune alterations. Acute patients are characterized by the metabolic and lipidomic dysregulation that accompanies the exacerbated immunological response, resulting in a slow recovery time with a maximum probability of around 62 days. As a manifestation of the heterogeneity in the metabolic phenoreversion, age and severity become factors that modulate their normalization time which, in turn, correlates with changes in the atherogenesis-associated chemokine MCP-1. Our results are consistent with a model where the slow metabolic normalization in acute patients results in enhanced atherosclerotic risk, in line with the recent observation of an elevated number of cardiovascular episodes found in post-COVID-19 cohorts.

4.
NMR Biomed ; 35(2): e4637, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34708437

RESUMO

COVID-19 is a systemic infectious disease that may affect many organs, accompanied by a measurable metabolic dysregulation. The disease is also associated with significant mortality, particularly among the elderly, patients with comorbidities, and solid organ transplant recipients. Yet, the largest segment of the patient population is asymptomatic, and most other patients develop mild to moderate symptoms after SARS-CoV-2 infection. Here, we have used NMR metabolomics to characterize plasma samples from a cohort of the abovementioned group of COVID-19 patients (n = 69), between 3 and 10 months after diagnosis, and compared them with a set of reference samples from individuals never infected by the virus (n = 71). Our results indicate that half of the patient population show abnormal metabolism including porphyrin levels and altered lipoprotein profiles six months after the infection, while the other half show little molecular record of the disease. Remarkably, most of these patients are asymptomatic or mild COVID-19 patients, and we hypothesize that this is due to a metabolic reflection of the immune response stress.


Assuntos
COVID-19/metabolismo , Lipidômica , Espectroscopia de Ressonância Magnética/métodos , Metabolômica , SARS-CoV-2 , COVID-19/imunologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos
5.
Emergencias ; 34(6): 418-427, 2022 12.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36625691

RESUMO

OBJECTIVES: To describe the sociodemographic characteristics of and the health care resources used to treat patients aged 65 years or older who come to hospital emergency departments (EDs) in Spain, according to age groups. MATERIAL AND METHODS: We studied the phase-1 data for the EDEN cohort (Emergency Department and Elder Needs). Forty Spanish EDs collected data on all patients aged 65 years or older who were treated on the first 7 days in April 2019. We registered information on 6 sociodemographic and 5 function variables for all patients. For health resource use we used 6 diagnostic, 13 therapeutic, and 5 physical structural variables, for a total of 24 variables. Differences were analyzed according to age in blocks of 5 years. RESULTS: A total of 18 374 patients with a median age of 78 years were included; 55% were women. Twenty-seven percent arrived by ambulance, 71% had not previously been seen by a physician, and 13% lived alone without assistance. Ten percent had a high level of functional dependence, and 14% had serious comorbidity. Resources used most often were blood analysis (in 60%) and radiology (59%), analgesics (25%), intravenous fluids (21%), antibiotics (14%), oxygen (13%), and bronchodilators (11%). Twenty-six percent were kept under observation in the ED, 26% were admitted to wards, and 2% were admitted to intensive care units (ICUs). The median stay in the ED was 3.5 hours, and the median hospital stay was 7 days. Sociodemographic characteristics changed according to age. Functional dependence worsened with age, and resource requirements increased in general. However, benzodiazepine use was unaffected, while the use of nonsteroidal anti-inflammatory drugs and ICU admission decreased. CONCLUSION: The functional dependence of older patients coming to EDs increases with age and is associated with a high level of health care resource use, which also increases with age. Planners should take into consideration the characteristics of the older patients and the proportion of the caseload they represent when arranging physical spaces and designing processes for a specific ED.


OBJETIVO: Investigar las características sociodemográficas y consumo de recursos de los pacientes de 65 o más años que consultan en servicios de urgencias hospitalarios (SUH) en España, y su modificación por grupos etarios. METODO: Se utilizaron datos de la cohorte EDEN obtenidos en fase 1 (Emergency Department and Elder Needs). Cuarenta SUH españoles incluyeron todos los pacientes de $ 65 años atendidos del 1-4-2019 al 7-4-2019 (7 días). Se analizaron 6 características sociodemográficas, 5 funcionales y 24 referidas a consumo de recursos (6 diagnósticos, 13 terapéuticos, 5 estructurales) y sus cambios a medida que avanza la edad (agrupada en bloques de 5 años). RESULTADOS: Se analizaron 18.374 pacientes (mediana edad: 78 años; 55% mujeres). El 27% acude a urgencias en ambulancia, el 71% sin consulta médica previa y el 13% vive solo sin cuidadores. Funcionalmente, el 10% tiene dependencia grave y el 14% comorbilidad grave. La solicitud de analítica sanguínea (60% de casos) y radiología (59%) destaca entre el consumo de recursos diagnósticos, y el uso de analgésicos (25%), sueroterapia (21%), antibioticoterapia (14%), oxigenoterapia (13%) y broncodilatadores (11%), entre los terapéuticos. El 26% requiere observación en urgencias, el 26% hospitalización y el 2% cuidados intensivos. La mediana de estancia en urgencias es de 3:30 horas y la de hospitalización es de 7 días. Las características sociodemográficas se modifican con la edad, las funcionales empeoran y el consumo de recursos aumenta (excepto benzodiacepinas, que no se modifica, y antinflamatorios no esteroideos y cuidados intensivos, que disminuye). CONCLUSIONES: Las características funcionales de la población mayor que consulta en los SUH empeora a medida que su edad avanza, y se asocia a un consumo de recursos alto que también se incrementa con la edad. Las características de esta población y su proporción en un determinado SUH deben tenerse en cuenta en su planificación estructural y funcional.


Assuntos
Serviço Hospitalar de Emergência , Estado Funcional , Humanos , Feminino , Idoso , Masculino , Hospitalização , Tempo de Internação , Recursos em Saúde
6.
Cardiovasc Diabetol ; 20(1): 155, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34320987

RESUMO

BACKGROUND: Metabolic syndrome (MetS) is a multimorbid long-term condition without consensual medical definition and a diagnostic based on compatible symptomatology. Here we have investigated the molecular signature of MetS in urine. METHODS: We used NMR-based metabolomics to investigate a European cohort including urine samples from 11,754 individuals (18-75 years old, 41% females), designed to populate all the intermediate conditions in MetS, from subjects without any risk factor up to individuals with developed MetS (4-5%, depending on the definition). A set of quantified metabolites were integrated from the urine spectra to obtain metabolic models (one for each definition), to discriminate between individuals with MetS. RESULTS: MetS progression produces a continuous and monotonic variation of the urine metabolome, characterized by up- or down-regulation of the pertinent metabolites (17 in total, including glucose, lipids, aromatic amino acids, salicyluric acid, maltitol, trimethylamine N-oxide, and p-cresol sulfate) with some of the metabolites associated to MetS for the first time. This metabolic signature, based solely on information extracted from the urine spectrum, adds a molecular dimension to MetS definition and it was used to generate models that can identify subjects with MetS (AUROC values between 0.83 and 0.87). This signature is particularly suitable to add meaning to the conditions that are in the interface between healthy subjects and MetS patients. Aging and non-alcoholic fatty liver disease are also risk factors that may enhance MetS probability, but they do not directly interfere with the metabolic discrimination of the syndrome. CONCLUSIONS: Urine metabolomics, studied by NMR spectroscopy, unravelled a set of metabolites that concomitantly evolve with MetS progression, that were used to derive and validate a molecular definition of MetS and to discriminate the conditions that are in the interface between healthy individuals and the metabolic syndrome.


Assuntos
Síndrome Metabólica/urina , Metaboloma , Metabolômica , Espectroscopia de Prótons por Ressonância Magnética , Adolescente , Adulto , Idoso , Biomarcadores/urina , Estudos de Casos e Controles , Progressão da Doença , Europa (Continente) , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Urinálise , Adulto Jovem
8.
ChemSusChem ; 7(9): 2597-608, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25056736

RESUMO

This work analyses the composition, morphology, and thermal behavior of the carbonaceous materials deposited during the thermal treatment of bio-oil (thermal pyrolytic lignin-TPL). The bio-oil was obtained by flash pyrolysis of lignocellulosic biomass (pine sawdust), and the TPLs were obtained in the 400-700 °C range. The TPLs were characterized by performing elemental analysis; (13)C NMR, Raman, FTIR, and X-ray photoelectron spectroscopy; SEM; and temperature-programmed oxidation analyzed by differential thermogravimetry and differential scanning calorimetry. The results are compared to a commercial lignin (CL). The TPLs have lower oxygen and hydrogen contents and a greater aromaticity and structural order than the CL material. Based on these features, different valorization routes are proposed: the TPL obtained at 500 °C is suitable for use as a fuel, and the TPL obtained at 700 °C has a suitable morphology and composition for use as an adsorbent or catalyst support.


Assuntos
Biocombustíveis , Carbono/química , Temperatura , Biomassa , Lignina/química
9.
PLoS One ; 5(6): e11210, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20585445

RESUMO

The identification of CYP2C9 and VKORC1 genes has strongly stimulated the research on pharmacogenetics of coumarins in the last decade. We assessed the combined influence of CYP2C9 *2 and *3, and VKORC1 c.-1639G>A, 497C>G, and 1173C>T variants, on acenocoumarol dosage using a novel algorithm approach, in 193 outpatients who had achieved stable anticoagulation. We constructed an "acenocoumarol-dose genotype score" (AGS, maximum score = 100) based on the number of alleles associated with higher acenocoumarol dosage carried by each subject for each polymorphism. The mean AGS was higher in the high-dose (> 28 mg/week) compared with the low-dose (< 7 mg/week) group (mean(SEM) of 84.1+/-3.4 vs. 62.2+/-4.8, P = 0.008). An AGS > 70 was associated with an increased odds ratio (OR) of requiring high acenocoumarol dosage (OR: 3.347; 95%CI: 1.112-10.075; P = 0.032). In summary, although more research is necessary in other patient cohorts, and this algorithm should be replicated in an independent sample, our data suggest that the AGS algorithm could be used to help discriminating patients requiring high acenocoumarol doses to achieve stable anti-coagulation.


Assuntos
Acenocumarol/farmacologia , Algoritmos , Alelos , Anticoagulantes/farmacologia , Hidrocarboneto de Aril Hidroxilases/genética , Oxigenases de Função Mista/genética , Acenocumarol/farmacocinética , Anticoagulantes/farmacocinética , Área Sob a Curva , Citocromo P-450 CYP2C9 , Relação Dose-Resposta a Droga , Humanos , Farmacogenética , Polimorfismo Genético , Vitamina K Epóxido Redutases
11.
PLoS One ; 3(12): e4080, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19114997

RESUMO

Presenilin1 (PS1) is a component of the gamma-secretase complex mutated in cases of Familial Alzheimer's disease (FAD). PS1 is synthesized as a 50 kDa peptide subsequently processed to two 29 and 20 kDa subunits that remain associated. Processing of PS1 is inhibited by several mutations detected in FAD patients. PS1 acts as negative modulator of beta-catenin.Tcf-4 transcriptional activity. In this article we show that in murine embryonic fibroblasts (MEFs) the mechanisms of action of the processed and non-processed forms of PS1 on beta-catenin.Tcf-4 transcription are different. Whereas non-processed PS1 inhibits beta-catenin.Tcf-4 activity through a mechanism independent of gamma-secretase and associated with the interaction of this protein with plakoglobin and Tcf-4, the effect of processed PS1 is prevented by gamma-secretase inhibitors, and requires its interaction with E- or N-cadherin and the generation of cytosolic terminal fragments of these two cadherins, which in turn destabilize the beta-catenin transcriptional cofactor CBP. Accordingly, the two forms of PS1 interact differently with E-cadherin or beta-catenin and plakoglobin: whereas processed PS1 binds E-cadherin with high affinity and beta-catenin or plakoglobin weakly, the non-processed form behaves inversely. Moreover, contrarily to processed PS1, that decreases the levels of c-fos RNA, non-processed PS1 inhibits the expression c-myc, a known target of beta-catenin.Tcf-4, and does not block the activity of other transcriptional factors requiring CBP. These results indicate that prevention of PS1 processing in FAD affects the mechanism of repression of the transcriptional activity dependent on beta-catenin.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Presenilina-1/metabolismo , Fatores de Transcrição TCF/genética , Transcrição Gênica , beta Catenina/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Proliferação de Células , Células Cultivadas , Humanos , Camundongos , Fatores de Transcrição TCF/metabolismo , Transfecção , beta Catenina/genética
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