Represión catabólica de la ruta de degradación de tetralina en "Sphingopyxis macrogolitabida" TFA

Programa Oficial de Postgrado en BiotecnologíaEl proyecto de tesis denominado ¿Represión catabólica de la ruta de degradación de tetralina en Sphyngopyxis macrogolitabida TFA¿ presentado por la doctoranda Dña. Helena Gómez Álvarez ha sido realizado en el área de Microbiología perteneciente al Departamento de Biología Molecular e Ingeniería Bioquímica de la Universidad Pablo de Olavide. El objetivo de esta Tesis ha sido el estudio del fenómeno de represión catabólica en Sphingopyxis macrogolitabida TFA. Este tipo de regulación global está bien caracterizado en las principales bacterias modelo, pero su base molecular es totalmente desconocida dentro del orden Sphingomonadales, a pesar de que este grupo alberga varios géneros de bacterias con un relevante potencial en biorremediación. Dado que en TFA el metabolismo del compuesto aromático tetralina (1,2,3,4-tetrahidronaftaleno) está completamente caracterizado, se ha empleado esta ruta de degradación como referencia para el estudio de la base molecular que dirige el proceso de represión catabólica en presencia de otra fuente de carbono preferencial (ß-hidroxibutirato) en el medio. Durante el desarrollo de esta Tesis se ha realizado un análisis de la fisiología de la bacteria durante el crecimiento en condiciones de represión catabólica. Para ello, se ha estudiado la inducción de los genes de degradación de tetralina (sujetos a represión catabólica) in vivo y a lo largo del tiempo en distintas condiciones de disponibilidad de carbono. También se han identificado y analizado los cambios ocurridos en el proteoma de la bacteria como consecuencia del estímulo de represión catabólica. Con este fin, se han desarrollado experimentos de resolución del proteoma en geles bidimensionales y se han analizado las diferencias globales gracias al marcaje de las proteínas con fluoróforos (técnica 2D-DIGE) o con metionina radiactiva. El último tipo de estudio se desarrolló gracias a una estancia de investigación en el laboratorio del Prof. Michael Hecker (Greifswald, Alemania). Aparte del estudio fisiológico, se ha analizado la implicación de varios elementos específicos en el mecanismo de represión catabólica, elegidos bien por su expresión diferencial en condiciones de represión catabólica en los experimentos de proteómica o por su implicación en el mismo proceso de regulación global en otras bacterias. Así, se han construido mutantes de deleción o mutantes condicionales en los genes de TFA codificantes para: el regulador transcripcional CdnL, una proteína transductora de señales con dominios CBS, el sistema de dos componentes FixL-FixJ y las proteínas HPr y HPrK del sistema fosfotransferasa tipo Ntr (PTSNtr). Para la caracterización del fenotipo de estas estirpes mutantes se han realizado análisis del crecimiento, ensayos de expresión de los genes thn (mediante qRT-PCR o ensayo ß-galactosidasa) y medida de la acumulación del polímero de reserva polihidroxibutirato (PHB). Únicamente se ha podido confirmar la participación de la proteína HPr en el proceso de represión catabólica, cuya deleción altera también la acumulación de gránulos de PHB en las células.Universidad Pablo de Olavide. Departamento de Biología Molecular e Ingeniería Bioquímic

Combination of degradation pathways for naphthalene utilization in Rhodococcus sp. strain TFB

This is an open access article under the terms of the Creative Commons Attribution License.Rhodococcus sp. strain TFB is a metabolic versatile bacterium able to grow on naphthalene as the only carbon and energy source. Applying proteomic, genetic and biochemical approaches, we propose in this paper that, at least, three coordinated but independently regulated set of genes are combined to degrade naphthalene in TFB. First, proteins involved in tetralin degradation are also induced by naphthalene and may carry out its conversion to salicylaldehyde. This is the only part of the naphthalene degradation pathway showing glucose catabolite repression. Second, a salicylaldehyde dehydrogenase activity that converts salicylaldehyde to salicylate is detected in naphthalene-grown cells but not in tetralin- or salicylate-grown cells. Finally, we describe the chromosomally located nag genes, encoding the gentisate pathway for salicylate conversion into fumarate and pyruvate, which are only induced by salicylate and not by naphthalene. This work shows how biodegradation pathways in Rhodococcus sp. strain TFB could be assembled using elements from different pathways mainly because of the laxity of the regulatory systems and the broad specificity of the catabolic enzymes.Work in the authors laboratory was supported by the Spanish Ministry of Economy and Competitivity, grants BIO2011-24003 and CSD2007-00005, and by the Andalusian Government, grants P05-CVI-131 and P07-CVI-2518.Peer Reviewe

Removal of wood dyes from aqueous solutions by sorption on untreated pine (Pinus radiata) sawdust

In this work, the possibility of using un-treated pine (Pinus radiata) sawdust as biosorbent for the removal of three wood dyes (blue, red and black) from aqueous solutions was investigated. The BET surface area of the material was 1.55 ± 0.81 m2 g−1 using N2 at − 196 °C and 17.83 ± 0.032 m2 g−1 using CO2 at 0 °C. The point of zero charge was 4.8. In addition, the material was characterized before and after adsorption by surface analytical techniques. Assays were performed to analize the stability of wood dyes with time and pH and also to estimate the pKa values. Batch adsorption experiments were performed and the influence of experimental parameters such as contact time (up to equilibrium), stirring rate (100 and 210 rpm), adsorbent dose (2–10 g L−1), pH (2–9) and initial dye concentration (5 and 300 mg L−1) were studied. The optimum conditions were pH 2 and adsorbent dose of 6 g L−1 and the highest adsorption percentages achieved at 5 mg L−1 were: 100.0% for the blue, 99.7% for the black and 92.4% for the red. For 300 mg L−1 adsorption efficiency decreased to 85.6, 57.0 and 63.8% for the blue, black and red ones, respectively. Kinetic data were best fitted to the pseudo-second order model, suggesting a chemisorption process. Freundlich and Dubidin-Radushkevich were the best isotherm models. Regeneration study showed that un-treated pine sawdust could be reused efficiently for red dye removal at least in up to four repeated adsorption–desorption cycles using NaOH as desorption agentOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was financial supported by Xunta de Galicia (ED431B 2020/039)S

Preparation of activated carbon from pine (Pinus radiata) sawdust by chemical activation with zinc chloride for wood dye adsorption

Wastewater containing dyes are released into water bodies generating serious problems in human health and marine life. To contribute to the solution of this problem, a novel activated carbon was prepared from untreated pine (Pinus radiata) sawdust by dry chemical activation with ZnCl2 and was used for wood dye adsorption. The carbon was characterized by point of zero charge, N2 and CO2 adsorption isotherms, SEM-EDX, and FTIR. N2 and CO2 surface areas were 471.4 and 319.5 m2 g−1, respectively, with 91% of micropores. Wood dye adsorption was studied in function of pH (2–12), adsorbent dose (0.1–4 g L−1), time (up to 48 h for blue and red and 12 h for black), and initial concentration (5–500 mg L−1). The equilibrium data for the blue and black dyes were satisfactorily fitted to the Freundlich model while those for the red dye to the Langmuir model. Kinetic data were explained by the pseudo-second order (chemisorption process) and intraparticle diffusion models. At 5 mg L−1, a 100% removal efficiency was achieved at all pH for the blue dye, whereas for the red and black, natural pH (5.1) and pH = 2, respectively, led to the best removal efficiencies, 96 and 56%. Increasing concentration above 25 mg L−1 significantly reduced adsorption efficiency for blue and red dyes. For the black dye increasing the dose to 1 g L−1, the adsorption efficiency reached 82% at 25 mg L−1. High removal efficiencies were achieved for all dyes at 25 mg L−1 and 4 g L−1Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was supported by Consellería de Educación, Universidade e Formación Profesional, Xunta de Galicia, grant number ED431B 2020/039S

LPAC syndrome associated with deletion of the full exon 4 in a ABCB4 genetic mutation in a patient with hepatitis C

El síndrome LPAC (low-phospholipid-associated cholelithiasis syndrome) está asociado a mutaciones del gen ABCB4, que codifica la proteína MDR3, esencial en la secreción de fosfatidilcolina en las sales biliares. Este síndrome se caracteriza por una mayor prevalencia en mujeres, síntomas biliares en adultos jóvenes y excelente respuesta al ácido ursodesoxicólico (AUDC). Presentamos el caso de un hombre de 48 años con hepatitis C, genotipo 1b, fibrosis F3, nula respuesta Peg-IFN-α-2b/ribavirina y cólicos nefríticos de repetición. En 2011 desarrolló ictericia, prurito y dolor cólico epigástrico acompañado de aumento sérico de AST, ALT, GGT, bilirrubina y alfafetoproteína, y carga viral (14.600.000 UI/ml). La endoscopia oral, la ecoendoscopia, la angio-TAC y la ecografía-doppler evidenciaron hepatopatía crónica no cirrótica. El cuadro se autolimitó y un año después sufrió un episodio similar. Iniciamos tratamiento con AUDC, con excelente respuesta clínica. El estudio inmunohistoquímico y la secuenciación completa del gen ABCB4 no mostraron alteraciones. La técnica MLPA® detectó deleción heterocigota del exón 4 completo y confirmó la sospecha de síndrome LPAC.Low-phospholipid-associated cholelithiasis syndrome (LPAC) is associated with ABCB4 genetic mutation. ABCB4 encodes MDR3 protein, involved in biliary phosphatidylcholine excretion. Higher prevalence in women, biliary symptoms in young adults and ursodesoxycholic acid (UDCA) response are the main features. We report the case of a 48-year-old man with hepatitis C, genotype 1b, fibrosis F3, null responder to Peg-IFNα2b/ribavirin and nephritic colic. In 2011 he developed jaundice, pruritus and epigastric pain. He showed increased serum levels of AST, ALT, GGT, bilirubin and alpha-fetoprotein, and viral load (14,600,000IU/mL). Pancreatic CT, endoscopic ultrasonography and echo-Doppler showed non cirrhotic chronic liver disease. The episode resolved spontaneously and one year later he suffered a similar episode. UDCA was started with excellent response. An immunohistochemistry study and sequencing of ABCB4 did not find alteration. MLPA® technique detected heterozygous deletion of the full exon 4 confirming LPAC syndrome diagnosis

Efficacy of bosentan in patients with refractory thromboangiitis obliterans (Buerger disease): A case series and review of the literature

The cornerstone of therapy in thromboangiitis obliterans (TAO) is complete abstinence from tobacco. In addition to discontinuation of cigarette smoking, very few pharmacological and surgical options of controversial efficacy are available to date. New therapeutic options with greater efficacy are clearly needed to properly manage these patients. In this preliminary study, we assessed the effectiveness and safety of bosentan in a case series of 8 adults with TAO and severe ischemic ulceronecrotic lesions who were treated with bosentan after inadequate response to platelet inhibitors, vasodilators, and intravenous alprostadil. Additionally, we reviewed 18 well-documented patients with refractory TAO treated with bosentan, which was previously reported (PubMed 1965-2015). These 26 patients formed the basis of our present analysis. All were current smokers. The median duration of bosentan treatment (SD) was 4.5 +/- 4 months (range 3-16). Eleven patients (42%) were unable to completely abstain from smoking during their follow-up. With bosentan treatment, no new ischemic lesions were observed in the target extremities. A complete therapeutic response was achieved in 80% of patients, whereas a partial response was observed in 12%. Two patients (8%) ultimately required amputation despite treatment. After discontinuation of bosentan, patients were followed for a median of 20 +/- 14 months (range 3-60). Two patients whose trophic lesions had healed relapsed. When comparing patients who gave up smoking with those who were unable to completely abstain from smoking during follow-up, no significant differences were found in efficacy outcomes. Four patients (15%) developed adverse events, requiring bosentan discontinuation in 1 case. These preliminary data suggest that bosentan may be considered a therapeutic option for treatment of cases of severe TAO refractory to conventional treatment, and merit further evaluation in larger controlled, randomized clinical studies

El control en los tiempos del coronavirus

Bajo el estado de alarma para frenar la pandemia de COVID-19 en España se han recortado libertades personales y civiles a través del decreto de confinamiento obligatorio. El control social se ha impuesto por ley, pero también ha operado un control desde los ciudadanos para los ciudadanos. Este artículo, fruto de entrevistas y encuestas, tiene por objetivo analizar de qué manera la población ha aceptado el control social y en qué medida ha contribuido al mismo. En el presente texto se muestra la diversidad de reacciones y comportamientos en los procesos de asimilación de las nuevas medidas.Under the State of alarm aiming to halt the spread of COVID-19, personal and civil liberties have been cut through the national lockdown. Social control has been imposed by law and restrictions, but control has also operated from citizens to citizens. Based on the results of interviews and surveys we've done, we can point out how the population has accepted social control and how they have contributed to the constitution of this state. This research shows the diversity of reactions and behaviors in the assimilation of the new measures

La sostenibilidad en los proyectos de ingeniería

El Trabajo de Fin de Grado representa la última prueba para que el estudiante de grado demuestre que está preparado para ejercer como ingeniero, elaborando y defendiendo un proyecto de envergadura. El proyecto debe cumplir todos los requisitos que se exigen a un proyecto de ingeniería, desde el análisis del problema hasta la presentación de una solución. Los autores del presente trabajo pensamos que todo proyecto de ingeniería debe incorporar un informe de sostenibilidad que demuestre que el proyecto es sostenible en los ámbitos social, ambiental y económico. Existe poca experiencia en este tema, tanto en la empresa como en la universidad, ya que las empresas (algunas) hace pocos años que han incorporado la sostenibilidad como uno de los criterios de realización de sus proyectos y las universidades apenas han comenzado a trabajar en esa dirección. En este trabajo se presentan algunas reflexiones sobre cómo debería ser tratada la sostenibilidad en un proyecto de ingeniería, y en particular cómo se pueden aplicar estas ideas al Trabajo de Fin de Grado.Postprint (published version

Liver injury in non-alcoholic fatty liver disease is associated with urea cycle enzyme dysregulation

The main aim was to evaluate changes in urea cycle enzymes in NAFLD patients and in two preclinical animal models mimicking this entity. Seventeen liver specimens from NAFLD patients were included for immunohistochemistry and gene expression analyses. Three-hundred-and-eighty-two biopsy-proven NAFLD patients were genotyped for rs1047891, a functional variant located in carbamoyl phosphate synthetase-1 (CPS1) gene. Two preclinical models were employed to analyse CPS1 by immunohistochemistry, a choline deficient high-fat diet model (CDA-HFD) and a high fat diet LDLr knockout model (LDLr −/−). A significant downregulation in mRNA was observed in CPS1 and ornithine transcarbamylase (OTC1) in simple steatosis and NASH-fibrosis patients versus controls. Further, age, obesity (BMI > 30 kg/m), diabetes mellitus and ALT werefound to be risk factors whereas A-allele from CPS1 was a protective factor from liver fibrosis. CPS1 hepatic expression was diminished in parallel with the increase of fibrosis, and its levels reverted up to normality after changing diet in CDA-HFD mice. In conclusion, liver fibrosis and steatosis were associated with a reduction in both gene and protein expression patterns of mitochondrial urea cycle enzymes. A-allele from a variant on CPS1 may protect from fibrosis development. CPS1 expression is restored in a preclinical model when the main trigger of the liver damage disappears.The research leading to these results has received funding from the Consejería de Salud de la Junta de Andalucía under grant agreement PC-0148-2016-0148 and PE-0451-2018 and Instituto de Salud Carlos III under grant agreements CD21/00095, PI16/01842, PI19/01404, PI19/00589, IFI18/00041, FI20/00201, CD18/00126 and EHD18PI04/2021. Rocío Gallego-Durán has received the Andrew K Burroughs Fellowship from European Association for the Study of the Liver (EASL), Aprendizaje de Nuevas Tecnologías fellowship from Asociación Española para el Estudio del Hígado (AEEH) and CIBERehd Grant to support researcher’s mobility

Clinical characteristics and outcomes of thymoma-associated myasthenia gravis

[Background and purpose] Prognosis of myasthenia gravis (MG) in patients with thymoma is not well established. Moreover, it is not clear whether thymoma recurrence or unresectable lesions entail a worse prognosis of MG.[Methods] This multicenter study was based on data from a Spanish neurologist-driven MG registry. All patients were aged >18 years at onset and had anti-acetylcholine receptor antibodies. We compared the clinical data of thymomatous and nonthymomatous patients. Prognosis of patients with recurrent or nonresectable thymomas was assessed.[Results] We included 964 patients from 15 hospitals; 148 (15.4%) had thymoma-associated MG. Median follow-up time was 4.6 years. At onset, thymoma-associated MG patients were younger (52.0 vs. 60.4 years, p < 0.001), had more generalized symptoms (odds ratio [OR]: 3.02, 95% confidence interval [CI]: 1.95–4.68, p < 0.001) and more severe clinical forms according to the Myasthenia Gravis Foundation of America (MGFA) scale (OR: 1.6, 95% CI: 1.15–2.21, p = 0.005). Disease severity based on MGFA postintervention status (MGFA-PIS) was higher in thymomatous patients at 1 year, 5 years, and the end of follow-up. Treatment refractoriness and mortality were also higher (OR: 2.28, 95% CI: 1.43–3.63, p = 0.001; hazard ratio: 2.46, 95% CI: 1.47–4.14, p = 0.001). Myasthenic symptoms worsened in 13 of 27 patients with recurrences, but differences in long-term severity were not significant. Fifteen thymomatous patients had nonresectable thymomas with worse MGFA-PIS and higher mortality at the end of follow-up.[Conclusions] Thymoma-associated MG patients had more severe myasthenic symptoms and worse prognosis. Thymoma recurrence was frequently associated with transient worsening of MG, but long-term prognosis did not differ from nonrecurrent thymoma. Patients with nonresectable thymoma tended to present severe forms of MG.This work is supported by Fondo de Investigaciones Sanitarias (FIS) grant FIS19/01774, Instituto de Salud Carlos III and cofunded by the European Union (ERDF/ESF, A Way to Make Europe/Investing in Your Future). Rodrigo Álvarez-Velasco was supported by a PhD for Medical Doctors grant from the Pla Estratègic de Recerca i Innovació en Salut (PERIS), Generalitat de Catalunya (SLT008/18/00207). Elena Cortés-Vicente was supported by a Juan Rodés grant (JR19/00037) from the Fondo de Investigación en Salud, Instituto de Salud Carlos III, Ministry of Health (Spain).Peer reviewe