Análisis y evaluación del riesgo de micotoxinas en café

La población en general espera tener una alimentación cada vez más sana y segura, con alimentos nutritivos y asequibles. Desafortunadamente, antes durante y después de la cosecha, las materias primas y los productos procesados están sometidos a la contaminación por microorganismos y hongos y, en consecuencia, por sus metabolitos secundarios, las micotoxinas. El café es uno de estos productos. La presente tesis doctoral aborda nuevas técnicas analíticas para desvelar los contenidos de estas micotoxinas en café, y evalúa el “riesgo” que representa un producto tan fuertemente instaurado en la alimentación de numerosas sociedades a lo largo de todo el mundo. Entre las diferentes metodologías analíticas estudiadas se han seleccionado dos de ellas. La primera consiste en una extracción de multimicotoxinas con acetonitrilo/agua como extractante en Ultra-Turrax, que permite el análisis simultaneo de 18 micotoxinas (ocratoxina A, aflatoxina B1, B2, G1, G2, nivalenol, deoxinivalenol, toxinas HT-2 y T-2, diacetoxyscirpenol, fumonisinas B1y B2, zearalenona, eniatinas A, A1, B, B1, y beauvericina) en café tostado. La segunda consiste en la extracción con acetato de etilo/ácido fórmico con Ultra-Turrax, que permite la extracción simultanea de 21 micotoxinas (ocratoxina A, Aflatoxinas B1 B2, G1, G2, esterigmatocistina, nivalenol, deoxinivalenol, 3-acetoxi deoxinivalenol, 15-acetoxi deoxinivalenol, diacetoxyscirpenol, neosolaniol, toxinas HT-2 y T-2, fumonisinas B1 y B2, eniatinas A, A1, B, B1, y beuvericina) desde la bebida de café preparada para su consumo. La técnica instrumental consiste en una cromatografía líquida acoplada a espectrometría de masas de triple cuadrupolo (CL-EM/ EM). Las propuestas se han validado obteniendo resultados satisfactorios de acuerdo con la normativa aplicable europea en cuanto a los requisitos exigidos para los métodos analíticos (CE/657/2002). La aplicación de ambos métodos analíticos a muestras comercializadas revela un alto número de muestras contaminadas por micotoxinas: con rangos de contaminación en café tostado desde 0,10 μg/kg hasta 25,86 mg/kg, y en bebida de café desde 0,69 μg/kg hasta 282,89 μg/kg. Entre las micotoxinas encontradas cabe destacar la presencia de ocratoxina A (OTA), la única micotoxina legislada en café, detectada incluso a niveles superiores a los límites máximos establecidos (5,0 μg/kg) en un pequeño número de muestras. No obstante, una parte de las muestras analizadas no presenta contaminación por ninguna de las micotoxinas analizadas. Los diferentes tipos de café estudiados no muestran diferencias significativas en la mayoría de los casos. Si bien, algunas micotoxinas como OTA o deoxinivalenol entre otras, si muestran diferencias en función del tipo de procesado o del tipo de café. Con los datos de contaminación de café combinados con la base de datos de consumo de la EFSA, se ha calculado la ingesta diaria estimada de acuerdo con las recomendaciones de la OMS. Además, se ha realizado una evaluación del riesgo mediante comparación de la ingesta diaria estimada con parámetros toxicológicos de ingesta diaria tolerable e ingesta semanal tolerable. Tras la evaluación del riesgo en adultos y adolescentes españoles, se concluye que el consumo de café no representa un riesgo potencial por su contenido en micotoxinas. No obstante, la contaminación del café por micotoxinas afecta a la ingesta diaria estimada en la dieta total, especialmente en sectores de la población con alto consumo de café. La presencia y coexistencia de micotoxinas en café, los efectos toxicológicos de las mismas y la legislación actual del café, que solo contempla la ocratoxina A, muestran la necesidad de una legislación más completa, que regule un mayor número de micotoxinas en este producto.Nowadays population desires a healthy and safety diet, with nutritive and affordable foods. Unfortunately, before, during and/or after harvesting, food products are subject to contamination by microorganism and fungi, and consequently by their secondary metabolites, the mycotoxins. Mycotoxins are toxic compounds. There are approximately 400 recognized mycotoxins, but only a few of them are present in food commodities, and some mycotoxins are regulated in foods. Coffee is an agricultural food product and is subject to contamination, the only mycotoxin regulated in coffee is ochratoxin A. This Doctoral Thesis develops new analytical technics for quantification of mycotoxins contents in coffee. In addition, implement the risk assessment of this widely consume and deeply ingrained around the world product. Among the different analytical methodologies, two of them are selected. One for the analysis of roasted coffee, consisting in an extraction with acetonitrile/water for the simultaneous analysis of 18 mycotoxins (ochratoxin A, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, nivalenol, deoxynivalenol, T-2 and HT-2 toxin, diacetoxyscirpenol, fumonisin B1, fumonisin B2, zearalenone, enniatin A, enniatin A1, enniatin B, enniatin B1, and beauvericin); The other one for the analysis of coffee brews consisting in an extraction with ethyl acetate/formic acid 5% for the simultaneous analysis of 21 mycotoxins (ochratoxin A, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, sterigmatocystin, nivalenol, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyl deoxynivalenol, diacetoxyscirpenol, neosolaniol, HT-2 toxin, T-2 toxin, fumonisin B1, fumonisin B2, enniatin A, enniatin A1, enniatin B, enniatin B1, and beauvericin). Instrumentation consist in a liquid chromatography tandem mass spectrometry LC-MS/MS. Both analytical methods achieve satisfactory results according quality standards of the European Union regulation (CE/657/2002). The analyses of real samples indicate the presence of the studied mycotoxins in coffee beverages at concentrations ranging from 0.10 μg/kg to 25. 86mg/kg in roasted coffee samples, and from 0.69 μg/kg to 282.89 μg/kg in coffee brew. Ochratoxin A, the only mycotoxin regulated in coffee, is detected in samples, and in some cases concentration levels exceed the maximum limit established (5.0 μg/kg). However, some samples are mycotoxin free. The most coffee types do not show significant differences in the degradation of mycotoxins. Nevertheless, ochratoxin A and deoxynivalenol between others, show different behaviour by the different coffee types and coffee brewing methods. The estimated daily intake is calculated based on the recommendations of WHO. Data on mycotoxin concentrations in coffee samples, and food consumption data available from EFSA data base, have been used for the estimation. In addition, risk assessment has been performed for Spanish adults and adolescents via comparison with the tolerable daily intake or the tolerable weekly intake and with available studies of total diet. The results show that coffee intake does not represent a potential risk for consumers regarding individual mycotoxin contamination. However, contamination of coffee by mycotoxins likely affects the exposition of the total diet, and should be considered in future total diet studies. The presence and co-occurrence of mycotoxins in coffee, their toxic effects and current coffee legislation, that only include ochratoxin A, reaffirm the necessity of new coffee regulations which include a greater number of mycotoxins

Diseño de catalizadores laminares para la síntesis de nanotubos de carbono con altos rendimientos

La obtención de nanotubos de carbono CNT por el método de deposición catalítica en forma de vapor CCVD, está limitada por la falta de un modelo de crecimiento de CNT que pueda explicar satisfactoriamente los diversos resultados que se encuentran en la literatura. Las más recientes investigaciones en la síntesis de CNT se enfocan en la optimización de las condiciones de operación y el diseño del catalizador. Este trabajo enfatiza la importancia de la temperatura de calcinación para el diseño de catalizadores con una mayor actividad catalítica en la producción de nanotubos de carbono multicapa MWCNT. El proceso CCVD se realiza mediante la descomposición de metano a 1000ºC durante 30 min en una atmósfera CH4/H2 (97:3 v/v) en contacto con 50 mg de catalizador depositado sobre una navecilla de cerámica. Se emplearon 2 catalizadores compuestos Mx-Mg-Mo (Mx=Co,Ni) sintetizados por el método sol-gel. Se estableció una relación directa entre la temperatura de calcinación, las fases cristalográficas predominantes y los rendimientos de MWCNT obtenidos, empleando técnicas de DSC, XRD y Raman. Se obtuvieron rendimientos superiores a 3000 wt.% en presencia de las fases (Co/Ni)xMg1-xMoO4, las cuales se asocian con una buena dispersión del metal activo en la matriz soporte, lo que evita la desactivación del catalizador por sinterización masiva durante el proceso de nucleación. Se propuso un mecanismo de crecimiento de MWCNT empleando catalizadores laminares no porosos, que explica satisfactoriamente los altos rendimientos obtenidos en correspondencia con la morfología de los catalizadores y de los MWCNT observados por microscopía SEM y TEM

Impact of Arterial Stiffness on All-Cause Mortality in Patients Hospitalized With COVID-19 in Spain

Older age and cardiovascular comorbidities are well-known risk factors for all-cause mortality in patients with coronavirus disease 2019 (COVID-19). Hypertension and age are the 2 principal determinants of arterial stiffness (AS). This study aimed to estimate AS in patients with COVID-19 requiring hospitalization and analyze its association with all-cause in-hospital mortality. This observational, retrospective, multicenter cohort study analyzed 12 170 patients admitted to 150 Spanish centers included in the SEMI-COVID-19 Network. We compared AS, defined as pulse pressure ≥60 mm Hg, and clinical characteristics between survivors and nonsurvivors. Mean age was 67.5 (±16.1) years and 42.5% were women. Overall, 2606 (21.4%) subjects died. Admission systolic blood pressure (BP) <120 and ≥140 mm Hg was a predictor of higher all-cause mortality (23.5% and 22.8%, respectively, P<0.001), compared with systolic BP between 120 and 140 mm Hg (18.6%). The 4379 patients with AS (36.0%) were older and had higher systolic and lower diastolic BP. Multivariate analysis showed that AS and systolic BP <120 mm Hg significantly and independently predicted all-cause in-hospital mortality (adjusted odds ratio [ORadj]: 1.27, P=0.0001; ORadj: 1.48, P=0.0001, respectively) after adjusting for sex (males, ORadj: 1.6, P=0.0001), age tertiles (second and third tertiles, ORadj: 2.0 and 4.7, P=0.0001), Charlson Comorbidity Index (second and third tertiles, ORadj: 4.8 and 8.6, P=0.0001), heart failure, and previous and in-hospital antihypertensive treatment. Our data show that AS and admission systolic BP <120 mm Hg had independent prognostic value for all-cause mortality in patients with COVID-19 requiring hospitalization

Effect of temperature and presence of minor amount of metal on porous carbon materials derived from ZIF8 pyrolysis for electrocatalysis

11 figures, 4 tables.-- Supplementary information available.ZIF8 without and with adsorption of minor amounts of Co precursor have been pyrolized at different temperatures studying systematically the effect of carbonization temperature on the texture, composition and ORR performance both in acidic and basic media. The increase of pyrolysis temperature diminished the N content but increased the graphitic character. The trade-off between these two parameters in metal-free electrocatalysts resulted in an improvement of ORR performance, which is met for the highest pyrolysis temperature of 1000 ºC. Moreover, the adsorption of minor amount of Co precursor enhanced further the ORR performance, increased the graphitic character and the porosity of the resulting carbon material. Morphologically, these carbon materials kept the polyhedral shape of ZIF8 and were covered by graphitic nanostructures devoid of metal nanoparticles. Co metal catalysed the growth of these graphitic nanostructures and concomitantly is stabilized as monoatomic Co-Nx-C species preventing the agglomeration as metal nanoparticles. Therefore, the need of an acid washing step is avoided, which is usually necessary in the carbonization of other metal containing MOFs.Grants PID2020-119160RB-C21 and PID2019-104272RB-C51 funded by MCIN/AEI/10.13039/501100011033 and Aragón Government (Aragón T03_20R), and associated EU Regional Development Funds are gratefully acknowledged.Peer reviewe

Nanoestructuras de carbono unidimensionales: procesado sostenible en agua a través de nanocristales de celulosa

3 figures.[EN] Carbon nanostructures have attracted much attention in recent decades due to their extraordinary electrical and mechanical properties. These properties arise from the sp2 hybridisation of carbon, subsequently forming a wide range of materials. In particular, unidimensional carbon nanostructures may be mainly classified into carbon nanofibers, singlewalled and multi-walled carbon nanotubes. In order to exploit their properties, well defined processing strategies are needed for these nanostructures, preferably in water, which presents a great challenge as they are hydrophobic. Traditionally, non-volatile organic solvents have been used for such purpose, but the use of water as a solvent offers a less toxic and a more sustainable option. However, in order to comply with a full aqueous processing, carbon nanostructures require the use of surfactants, the majority of which are toxic and difficult to remove or their functionalization, thus altering their intrinsic electronic properties. For these reasons, novel and environmentally friendly alternatives are emerging, in particular through the use of natural or biologicallyderived dispersants. Following this trend, we highlight the strategy developed in recent years by the G-CNN group involving cellulose nanocrystals, with a special focus on their applications in biomedicine and conductive inks.[ES] Las nanoestructuras de carbono han cautivado a la comunidad científica en las últimas décadas debido a sus excelentes propiedades eléctricas y mecánicas. Estas propiedades surgen de la hibridación sp2 del carbono, capaz de derivar en una extensa gama de materiales. En particular, las nanoestructuras de carbono unidimensionales se clasifican mayormente en nanofibras de carbono, nanotubos de carbono de pared simple y de pared múltiple. Debido a su naturaleza hidrofóbica, su procesado en fase líquida supone todo un reto, y tradicionalmente se han empleado disolventes orgánicos no volátiles para trabajar con ellas, siendo necesario buscar una alternativa menos tóxica y sostenible como el agua. Sin embargo, para procesarlas en medio acuoso, se necesitan surfactantes, la mayoría de los cuales pueden ser tóxicos y difíciles de eliminar, o si no hay que funcionalizar químicamente las nanoestructuras de carbono, alterando así sus propiedades electrónicas intrínsecas. Por esta razón, están emergiendo nuevas alternativas más sostenibles, en particular mediante el empleo de dispersantes basados en fuentes renovables o biopolímeros. En el contexto de sta estrategia emergente, destacamos las investigaciones realizadas en el grupo de investigación G-CNN, basadas en nanocristales de celulosa, con énfasis en aplicaciones en el campo de la biomedicina o las tintas conductoras.Peer reviewe

Five-year incidence of chronic kidney disease (stage 3-5) and associated risk factors in a Spanish cohort: the MADIABETES Study.

OBJECTIVE:To evaluate the incidence rate of Chronic Kidney Disease (CKD) stage 3-5 (persistent decreased kidney function under 60 mL/min per 1.73 m2) among patients with type 2 diabetes over five years, to identify the risk factors associated with CKD, and develop a risk table to predict five-year CKD stage 3-5 risk stratification for clinical use. DESIGN:The MADIABETES Study is a prospective cohort study of 3,443 outpatients with type 2 diabetes mellitus, sampled from 56 primary health care centers (131 general practitioners) in Madrid (Spain). RESULTS:The cumulative incidence of CKD stage 3-5 at five-years was 10.23% (95% CI = 9.12-11.44) and the incidence density was 2.07 (95% CI = 1.83-2.33) cases per 1,000 patient-months or 2.48 (95% CI = 2.19-2.79) cases per 100 patient-years. The highest hazard ratio (HR) for developing CKD stage 3-5 was albuminuria ≥ 300 mg/g (HR = 4.57; 95% CI= 2.46-8.48). Furthermore, other variables with a high HR were age over 74 years (HR = 3.20; 95% CI = 2.13-4.81), a history of Hypertension (HR = 2.02; 95% CI = 1.42-2.89), Myocardial Infarction (HR= 1.72; 95% IC= 1.25-2.37), Dyslipidemia (HR = 1.68; 95% CI 1.30-2.17), duration of diabetes mellitus ≥ 10 years (HR = 1.46; 95% CI = 1.14-1.88) and Systolic Blood Pressure >149 mmHg (HR = 1.52; 95% CI = 1.02-2.24). CONCLUSIONS:After a five-year follow-up, the cumulative incidence of CKD is concordant with rates described in Spain and other countries. Albuminuria ≥ 300 mg/g and age over 74 years were the risk factors more strongly associated with developing CKD (Stage 3-5). Blood Pressure, lipid and albuminuria control could reduce CKD incidence of CKD in patients with T2DM

Comparison of characteristics according to the presence of CKD (Stage 3–5).

<p>¹. Stage 3–5 of K/DOQI</p><p>². Albumin excretion rate > 30 mg/g</p><p>SD: Standard Deviation; IQR: Interquartile range; BMI: Body mass index; SBP: Systolic Blood Pressure; DBP: Dyastolic Blood Pressure; FPG: Fasting plasma glucose; HbA1c: Glycated haemoglobin; LDL-C: low-density lipoprotein cholesterol; HDL-C: high-density lipoprotein cholesterol.</p><p>* Pearson’s chi-square method was applied for categorical variables, and Student’s t-test for continuous variables. Mann-Whitney U-test was applied to compare medians of duration of DM2.</p><p>Comparison of characteristics according to the presence of CKD (Stage 3–5).</p

Quantitative flow ratio en infarto de miocardio para la evaluación de lesiones en arterias no culpables.: Estudio piloto QIMERA

Introduction and objectives: Complete revascularization is recommended for the management of ST-segment elevation myocardial infarctions (STEMI). Although physiological evaluation is recommended for the assessment of nonculprit lesions, in this context, the use of fractional flow reserve (FFR) is limited. The quantitative flow ratio (QFR) is a new angiography-based tool for the assessment of functional severity. We evaluated the functional changes occurring in nonculprit lesions after the acute phase and the QFR/FFR correlation in non-infarct-related arteries. Methods: We recruited all patients with multivessel disease admitted to our institution due to STEMI from January 2016 through December 2017 who underwent staged interventions for the management of nonculprit lesions. We conducted a retrospective QFR assessment at both the index and the staged procedures and drew a comparison. Also, the QFR/FFR concordance and agreement were prospectively evaluated between January and May 2018 in a cohort of patients with STEMI and multivessel disease. Results: We analyzed a total of 131 lesions in 88 patients. During the initial procedure, 93.1% of the lesions were considered significant based on the angiography compared to only 56.3% studied through QFR (P ≤ .001). The QFR reassessment during the staged intervention brought this percentage down to 32.1%. All patients with QFR values ≥ 0.82 during the index procedure remained nonsignificant at the staged assessment. Both the FFR and the QFR were compared in 12 patients showing good agreement and a mean difference of 0.015 ± 0.02 (P > .1). Conclusions: The QFR-based physiological assessment of nonculprit lesions in STEMI patients led us to consider nonsignificant 40% of the lesions classified as significant by the angiography. Also, the QFR significantly increased from the acute phase to the staged procedure, indicative that in patients with QFR ≥ 0.82 in the acute phase a new coronary angiography procedure may be unnecessary.Introducción y objetivos: En pacientes con infarto agudo de miocardio con elevación del segmento ST y enfermedad multivaso se recomienda la revascularización completa. La evaluación funcional con reserva fraccional de flujo (RFF) de las arterias no culpables del infarto es limitada. El quantitative flow ratio (QFR) es una herramienta basada en la angiografía para valorar la gravedad funcional de las lesiones. Se analizaron la evolución funcional de las arterias no culpables del infarto tras la fase aguda y la correlación QFR/RFF en este contexto. Métodos: Se incluyeron pacientes ingresados con infarto agudo de miocardio con elevación del segmento ST entre enero de 2016 y diciembre de 2017, con enfermedad multivaso y revascularización diferida de lesiones no culpables. Se evaluaron retrospectivamente con QFR durante el procedimiento índice y el diferido, y se evaluó la concordancia QFR/RFF de manera prospectiva entre enero y mayo de 2018. Resultados: Se incluyeron 131 lesiones de 88 pacientes. Durante el procedimiento índice, el 93,1% de las lesiones se consideraron significativas de acuerdo con la angiografía, pero solo el 56,3% cuando se evaluaron con QFR (p 0,1). Conclusiones: La evaluación fisiológica mediante QFR de las lesiones en arterias no culpables del infarto descartó la significación en el 40% de las consideradas significativas por angiografía. El valor de QFR se incrementó significativamente del procedimiento índice al diferido, lo que sugiere que en pacientes con QFR ≥ 0,82 en la fase aguda podrían evitarse procedimientos diferidos innecesarios

Associated Risk Factors for Incident CKD (Stage 3–5) (n = 268) after five-year follow-up of 2,620 patients (Multivariable Cox Regression).

<p>aHR: Adjusted Hazard Ratio; CI: Confidence Interval; CKD: Chronic Kidney Disease; SBP: Systolic Blood Pressure.</p><p>Associated Risk Factors for Incident CKD (Stage 3–5) (n = 268) after five-year follow-up of 2,620 patients (Multivariable Cox Regression).</p

Flow diagram of participants.

<p>Flow diagram of participants.</p