Biodiesel production from sewage sludge using supported heteropolyacid as heterogeneous acid catalyst.

Phosphotungstic acid (HPW) and silicotungstic acid (HSiW) were tested as homogeneous and as heterogeneous catalysts (after immobilized on different supports as high surface area graphite -HSAG500-, montmorillonite -MMT- and alumina -Al2O3-) for the in situ transesterification of sewage sludge lipids. Both catalysts exhibited similar performance in homogeneous phase, with slightly higher biodiesel yield for HPW. When the different supports were tested with HPW, the maximum yield obtained follow the trend: MMT > HSAG500 > Al2O3, but a greater leaching of the heteropolyacid (HPA) was observed with MMT. Therefore, HSAG500 showed the best results with a good FAMEs profile. The percentage of active phase was optimized from 1 to 40%, reaching the optimum at 10%. A more heterogeneous surface is obtained with larger quantities, also favouring the HPA leaching. The reaction temperature and the use of sonication as pre-treatment were also optimized. The best results were obtained after sonication with HPW-HSAG500 (10%) as catalyst, catalyst/sludge ratio 1:2, MeOH/sludge ratio 33:1, 120 °C and 21 h of reaction time with a maximum biodiesel yield of 31.1 % (FAMEs/lipids). In view of the results obtained HPW supports on HSAG500 offers a novel alternative as heterogeneous acid catalyst for in situ transesterification using sewage sludge as raw material.

Cell adhesion and migration in disease: translational and therapeutic opportunities.

In September 2023 members of the cell adhesion and cell migration research community came together to share their latest research and consider how our work might be translated for clinical practice. Alongside invited speakers, selected speakers and poster presentations, the meeting also included a round table discussion of how we might overcome the challenges associated with research translation. This meeting report seeks to highlight the key outcomes of that discussion and spark interest in the cell adhesions and cell migration research community to cross the perceived valley of death and translate our work into therapeutic benefit.

Cooking, Digestion, and In Vitro Colonic Fermentation of Nigerian Wholegrains Affect Phenolic Acid Metabolism and Gut Microbiota Composition.

Wholegrains contain both fibre and phenolic acids (PAs), and their gastrointestinal modifications are critical for their bioavailability and bioactivity. We evaluated the modifications on the PA profile and gut microbiota composition of selected Nigerian wholegrains, following cooking and gastrointestinal digestion. Red fonio, red millet, red sorghum, and white corn were cooked, digested, and fermented using an in vitro colonic model. A total of 26 PA derivatives were quantified in soluble and bound fractions using Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS) analysis. DNA samples were analysed using 16S rRNA amplicon sequencing to profile the microbiota composition. The results show that cooking and digestion significantly affected the levels of PAs in all grains (p ≤ 0.05) compared to raw grains. Colonic fermentation resulted in a peak of total soluble PAs at 4-6 h for red sorghum and white corn and at 24 h for red millet and red fonio. Enterobacteriaceae genera were the most abundant at 24 h in all grains studied. 3-hydroxybenzaldehyde correlated positively with the relative abundance of Dorea and the mucus-degrader bacteria Akkermansia (p ≤ 0.05), whereas hydroferulic acid and isoferulic acid levels correlated negatively with Oscillospira and Ruminococcus (p ≤ 0.05), respectively. Our data indicate that cooking, digestion, and colonic fermentation affect the release of bound PAs from wholegrains and, consequently, their metabolic conversion. Furthermore, PA fermentation in the gut is associated with potentially relevant changes in the microbiota. This in vitro study provides the basis for the design of an in vivo human intervention study that can confirm the trends herein observed but also assess the impact on health outcomes.

Electrochemical degradation of naproxen from water by anodic oxidation with multiwall carbon nanotubes glassy carbon electrode.

Naproxen (NPX) degradation was investigated by anodic oxidation both at constant potential and by cyclic voltammetry, using this last technique for optimizing reaction conditions and catalyst properties. Three multiwall carbon nanotubes (MWCNTs)-promoted electrodes were used (MWCNT, MWCNT-COOH and MWCNT-NH2) and a two steps oxidation process was observed in all the cases. At the optimized conditions (volume of MWCNT = 15 µL), the influence of the scan rate indicates the diffusion-adsorption control of the process. Likewise, the kinetic study of NPX degradation at fix potential, considering two different stirring speeds (250 and 500 rpm), indicates that degradation rate increases with the stirring speed. After 20 h, NPX is degraded even an 82.5%, whereas the mineralization reaches almost 70%, as it was obtained from total organic carbon analysis. The pH effect was also analysed, in the range 5-11, observing a positive effect at low pH. Concerning the surface chemistry of the electrode, MWCNT-NH2, with the highest isoelectric point (4.70), is the most promising material due to the improved interactions with the reactant. From these observations, a pathway is proposed, which includes two steps of electrochemical oxidation followed by subsequent oxidation steps, until mineralization of the NPX, attributed mainly to active chlorine species and ·OH.

Carbon nanotube modified glassy carbon electrode for electrochemical oxidation of alkylphenol ethoxylate.

Electrochemical oxidation of an emerging pollutant, 2-(4-methylphenoxy)ethanol (MPET), from water has been studied by cyclic voltammetry (CV). Multiwall carbon nanotubes glassy carbon electrodes (MWCNT-GCE) were used as working electrode due to their extraordinary properties. The oxidation process is irreversible, since no reduction peaks were observed in the reverse scan. The electrocatalytic effect of MWCNT was confirmed as the oxidation peak intensity increases in comparison to bare-GCE. The effect of functional groups on MWCNT was also studied by MWCNT functionalized with NH2 (MWCNT-NH2) and COOH (MWCNT-COOH) groups. The oxidation peak current decreases in the following order: MWCNT > MWCNT-NH2 > MWCNT-COOH. Taking into account the normalized peak current, MWCNT-NH2 exhibits the best results due to its strong interaction with MPET. Under optimal conditions (pH = 5.0 and volume of MWCNT = 10 µL), degradation was studied for MWCNT-GCE and MWCNT-NH2-GCE. A complete MPET removal was observed using MWCNT-GCE after four CV cycles, for a volume/area (V/A) ratio equal to 19. In the case of MWCNT-NH2-GCE, the maximum MPET removal was close to 90% for V/A = 37, higher than that obtained for MWCNT-GCE at the same conditions (≈80%). In both cases, no organic by-products were detected.

Effect of sludge features and extraction-esterification technology on the synthesis of biodiesel from secondary wastewater treatment sludges.

Secondary sludge from municipal wastewater treatment plant is proposed as a promising alternative lipid feedstock for biodiesel production. A deep study combining different type of raw materials (sludge coming from the oxic, anoxic and anaerobic steps of the biological treatment) with different technologies (liquid-liquid and solid-liquid extractions followed by acid catalysed transesterification and in situ extraction-transesterification procedure) allows a complete comparison of available technologies. Different parameters - contact time, catalyst concentration, pretreatments - were considered, obtaining more than 17% FAMEs yield after 50min of sonication with the in situ procedure and 5% of H2SO4. This result corresponds to an increment of more than 65% respect to the best results reported at typical conditions. Experimental data were used to propose a mathematical model for this process, demonstrating that the mass transfer of lipids from the sludge to the liquid is the limiting step.

Photocatalytic degradation of 2-(4-methylphenoxy)ethanol over TiO2 spheres.

The photocatalytic TiO2-assisted decomposition of 2-(4-methylphenoxy)ethanol (MPET) in aqueous solution has been studied for the first time. The intermediate compounds of MPET photodegradation have been also determined. A toxic p-cresol is formed in significant quantities during the photocatalytic reaction. A solvent-exchange approach for a template-free preparation of spherical TiO2 particles has been described, which is based solely on precipitation of hydrous titania from aqueous titanium peroxo complex by using organic solvents. The proposed method favours the formation of spherical titania particles with a mean size varying from 50 to 260nm depending on the choice of solvent. The procedure for converting nonporous titania spheres into mesoporous material maintaining the same spherical morphology has been developed. The synthesized TiO2 spheres demonstrate a degree of MPET photo-degradation close to that of the commercial titania Aeroxide P25, besides being successfully recovered and reused for four reaction cycles without loss of photocatalytic activity. The effectiveness of the commercial Aeroxide P25 in MPET photodegradation, on the other hand, suffers 10-time drop during the third reaction cycle, which is attributed to its poor recoverability because the photocatalyst is composed of small particles of 20nm size.

Electrochemical reduction of nalidixic acid at glassy carbon electrode modified with multi-walled carbon nanotubes.

The aqueous phase electrochemical degradation of nalidixic acid (NAL) is studied in this work, using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as instrumental techniques. The promotional effect of multi-walled carbon nanotubes (MWCNT) on the performance of glassy carbon electrodes is demonstrated, being observed that these materials catalyze the NAL reduction. The effect of surface functional groups on MWCNT -MWCNT-COOH and MWCNT-NH2-was also studied. The modification of glassy carbon electrode (GCE) with MWCNT leads to an improved performance for NAL reduction following the order of MWCNT>MWCNT-NH2>MWCNT-COOH. The best behavior at MWCNT-GCE is mainly due to both the increased electrode active area and the enhanced MWCNT adsorption properties. The NAL degradation was carried out under optimal conditions (pH=5.0, deposition time=20s and volume of MWCNT=10µL) using MWCNT-GCE obtaining an irreversible reduction of NAL to less toxic products. Paramaters as the number of DPV cycles and the volume/area (V/A) ratio were optimized for maximize pollutant degradation. It was observed that after 15 DPV scans and V/A=8, a complete reduction was obtained, obtaining two sub-products identified by liquid chromatography-mass spectrometry (LC-MS).

Adsorption of emerging pollutants on functionalized multiwall carbon nanotubes.

Adsorption of three representative emerging pollutants - 1,8-dichlorooctane, nalidixic acid and 2-(4-methylphenoxy)ethanol- on different carbon nanotubes was studied in order to determine the influence of the morphological and chemical properties of the materials on their adsorption properties. As adsorbents, multiwall carbon nanotubes (MWCNTs) without functionalization and with oxygen or nitrogen surface groups, as well as carbon nanotubes doped with nitrogen were used. The adsorption was studied in aqueous phase using batch adsorption experiments, results being fitted to both Langmuir and Freundlich models. The adsorption capacity is strongly dependent on both the hydrophobicity of the adsorbates and the morphology of the adsorbents. Thermodynamic parameters were determined observing strong interactions between the aromatic rings of the emerging pollutant and the nitrogen modified adsorbents.

Performance of different carbonaceous materials for emerging pollutants adsorption.

The adsorption of three representative emerging pollutants over different kinds of carbonaceous adsorbents has been studied in this work. The adsorbates were nalidixic acid (NAL, representative of a pharmaceutical), 1,8-dichlorooctane (DCO, a chloroparaffin) and methyl-phenoxy-ethanol (MPET, a surfactant). Activated carbons, carbon nanofibers, carbon nanotubes and high surface area graphites have been tested as adsorbents. Adsorption isotherms, carried out in a batch system, were fitted using both a Langmuir and a Freundlich model. It was shown that the capacity of adsorption follows the order DCO≫NAL>MPET for all the adsorbents, and among the adsorbents, the external morphology (surface area and mesoporous volume) is the key parameter. The results from thermodynamic analysis show, however, that both morphological and chemical properties of both adsorbates and adsorbents influenced their behavior.

Inhibidores de serotonina en el tratamiento de la náusea y el vómito provocados por el tratamiento con quimioterapia antineoplásica / Serotonine inhibitors in the treatment of nausea and vomit provoked for the treatment with antineoplasic chemotherapy

El desarrollo de fármacos antieméticos es una de las áreas más estudiadas en la investigación oncológica. Los avances terapéuticos en este campo pueden resultar en mejoría inmediata de la calidad de vida de los pacientes en tratamiento con quimioterapia antineoplásica. Hace 15 años, los pacientes que recibían tratamiento altamente emetógeno tenían entre 10 y 15 episodios de vómito en las primera 24 horas posquimioterapia. En la actualidad esto se ha reducido de manera significativa y los mecanismos de producción de vómito anticipatorio resultan mejor controlados. Los inhibidores de serotonina representan una línea de tratamiento para la náusea y el vómito en los pacientes con cáncer, pero además han permitido un mayor conocimiento de la fisiopatología de estos trastornos, así como la mejor comprensión de los mecanismos fisiológicos de producción del vómito. A la luz de los distintos tipos de antieméticos, los inhibidores de serotonina representan un alternativa viable en los pacientes que no se benefician con otros tipos de antieméticos. Aunque su eficacia se ha demostrado en diversos estudios, se ha impugnado su uso de forma extensa por su alto costo; sin embargo, el avance en la mejoría de la calidad de vida de los pacientes oncológicos no está sujeto a discusión, por los escasos efectos adversos que provocan y su amplio perfil de seguridad

Cardiopatía en pacientes con síndrome de inmunodeficiencia adquirida (SIDA) ¿Una enfermedad olvidada? / Cardiopathy in patients with acquired immunodeficiency syndrome (AIDS). A forgotten disease?

En este artículo se abordan las alteraciones cardiacas en pacientes con SIDA y se dividen de acuerdo con su causa y su nivel de afección. Se mencionan las lesiones provocadas por agentes infecciosos tóxicos y medicamentos y por neoplasias

Antirretrovirales. Realidades y limitaciones / Antiretrovirals. Realities and limitations

En el contexto de la investigación actual de la infección por VIH, los antirretrovirales ocupan un lugar preponderante. La síntesis de nuevos fármacos y el descubrimiento de resistencias virales ha provocado la creación de terapéuticas combinadas más agresivas contra el virus y, a su vez, más efectivas para limitar dichas resistencias. La valoración de la efectividad de los antivirales se realiza por dos métodos actualmente catalogados como indicadores de la progresión o limitación de la infección por el VIH: conteo de linfocitos CD4 y determinación de copias de RNA viral en plasma (carga viral). Gracias a éstos se puede determinar la necesidad de terapéuticas únicas o combinadas y limitar el daño provocado por el virus y evitar la progresión a SIDA