17 research outputs found

    A simple high efficiency intra-islet transduction protocol using lentiviral vectors

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    Successful normalization of blood glucose in patients transplanted with pancreatic islets isolated from cadaveric donors established the proof-of-concept that Type 1 Diabetes Mellitus is a curable disease. Nonetheless, major caveats to the widespread use of this cell therapy approach have been the shortage of islets combined with the low viability and functional rates subsequent to transplantation. Gene therapy targeted to enhance survival and performance prior to transplantation could offer a feasible approach to circumvent these issues and sustain a durable functional β-cell mass in vivo. However, efficient and safe delivery of nucleic acids to intact islet remains a challenging task. Here we describe a simple and easy-to-use lentiviral transduction protocol that allows the transduction of approximately 80 % of mouse and human islet cells while preserving islet architecture, metabolic function and glucose-dependent stimulation of insulin secretion. Our protocol will facilitate to fully determine the potential of gene expression modulation of therapeutically promising targets in entire pancreatic islets for xenotransplantation purposes

    Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

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    This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe

    PAX4 preserves endoplasmic reticulum integrity preventing beta cell degeneration in a mouse model of type 1 diabetes mellitus

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    Mellado-Gil, José Manuel et al.[Aims/hypothesis]: A strategy to enhance pancreatic islet functional beta cell mass (BCM) while restraining inflammation, through the manipulation of molecular and cellular targets, would provide a means to counteract the deteriorating glycaemic control associated with diabetes mellitus. The aims of the current study were to investigate the therapeutic potential of such a target, the islet-enriched and diabetes-linked transcription factor paired box 4 (PAX4), to restrain experimental autoimmune diabetes (EAD) in the RIP-B7.1 mouse model background and to characterise putative cellular mechanisms associated with preserved BCM. [Methods]: Two groups of RIP-B7.1 mice were genetically engineered to: (1) conditionally express either PAX4 (BPTL) or its diabetes-linked mutant variant R129W (mutBPTL) using doxycycline (DOX); and (2) constitutively express luciferase in beta cells through the use of RIP. Mice were treated or not with DOX, and EAD was induced by immunisation with a murine preproinsulin II cDNA expression plasmid. The development of hyperglycaemia was monitored for up to 4 weeks following immunisation and alterations in the BCM were assessed weekly by non-invasive in vivo bioluminescence intensity (BLI). In parallel, BCM, islet cell proliferation and apoptosis were evaluated by immunocytochemistry. Alterations in PAX4- and PAX4R129W-mediated islet gene expression were investigated by microarray profiling. PAX4 preservation of endoplasmic reticulum (ER) homeostasis was assessed using thapsigargin, electron microscopy and intracellular calcium measurements. [Results]: PAX4 overexpression blunted EAD, whereas the diabetes-linked mutant variant PAX4R129W did not convey protection. PAX4-expressing islets exhibited reduced insulitis and decreased beta cell apoptosis, correlating with diminished DNA damage and increased islet cell proliferation. Microarray profiling revealed that PAX4 but not PAX4R129W targeted expression of genes implicated in cell cycle and ER homeostasis. Consistent with the latter, islets overexpressing PAX4 were protected against thapsigargin-mediated ER-stress-related apoptosis. Luminal swelling associated with ER stress induced by thapsigargin was rescued in PAX4-overexpressing beta cells, correlating with preserved cytosolic calcium oscillations in response to glucose. In contrast, RNA interference mediated repression of PAX4-sensitised MIN6 cells to thapsigargin cell death. [Conclusions/interpretation]: The coordinated regulation of distinct cellular pathways particularly related to ER homeostasis by PAX4 not achieved by the mutant variant PAX4R129W alleviates beta cell degeneration and protects against diabetes mellitus. The raw data for the RNA microarray described herein are accessible in the Gene Expression Omnibus database under accession number GSE62846.This work was funded by grants from the Consejeria de Salud, Fundacion Publica Andaluza Progreso y Salud, Junta de Andalucia (PI-0727-2010 to BRG and PI-0085-2013 to PIL), Consejeria de Economia, Innovacion y Ciencia (P10.CTS.6359 to BRG), Ministerio de Ciencia e Innovacion (BFU2013-42789-P to IQ) and the Ministerio de Economia y Competidividad, Instituto de Salud Carlos III co-funded by Fondos FEDER (PI10/00871 and PI13/00593 to BRG). NC-V is supported by a JDRF subsidy (17-2013-372 to BRG.). AM-M is a recipient of a Miguel Servet grant (CP14/00105) from the Instituto de Salud Carlos III co-funded by Fondos FEDER and EF-M is a recipient of a Juan de la Cierva Fellowship. PM is supported by Swiss National Science Foundation grant 310030-141162, and the European Union grant IMIDIA, C2008-T7. BOB is supported by grants from the Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Republic of Singapore.Peer Reviewe

    Niraparib in patients with metastatic castration-resistant prostate cancer and DNA repair gene defects (GALAHAD): a multicentre, open-label, phase 2 trial

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    Background Metastatic castration-resistant prostate cancers are enriched for DNA repair gene defects (DRDs) that can be susceptible to synthetic lethality through inhibition of PARP proteins. We evaluated the anti-tumour activity and safety of the PARP inhibitor niraparib in patients with metastatic castration-resistant prostate cancers and DRDs who progressed on previous treatment with an androgen signalling inhibitor and a taxane. Methods In this multicentre, open-label, single-arm, phase 2 study, patients aged at least 18 years with histologically confirmed metastatic castration-resistant prostate cancer (mixed histology accepted, with the exception of the small cell pure phenotype) and DRDs (assessed in blood, tumour tissue, or saliva), with progression on a previous next-generation androgen signalling inhibitor and a taxane per Response Evaluation Criteria in Solid Tumors 1.1 or Prostate Cancer Working Group 3 criteria and an Eastern Cooperative Oncology Group performance status of 0–2, were eligible. Enrolled patients received niraparib 300 mg orally once daily until treatment discontinuation, death, or study termination. For the final study analysis, all patients who received at least one dose of study drug were included in the safety analysis population; patients with germline pathogenic or somatic biallelic pathogenic alterations in BRCA1 or BRCA2 (BRCA cohort) or biallelic alterations in other prespecified DRDs (non-BRCA cohort) were included in the efficacy analysis population. The primary endpoint was objective response rate in patients with BRCA alterations and measurable disease (measurable BRCA cohort). This study is registered with ClinicalTrials.gov, NCT02854436. Findings Between Sept 28, 2016, and June 26, 2020, 289 patients were enrolled, of whom 182 (63%) had received three or more systemic therapies for prostate cancer. 223 (77%) of 289 patients were included in the overall efficacy analysis population, which included BRCA (n=142) and non-BRCA (n=81) cohorts. At final analysis, with a median follow-up of 10·0 months (IQR 6·6–13·3), the objective response rate in the measurable BRCA cohort (n=76) was 34·2% (95% CI 23·7–46·0). In the safety analysis population, the most common treatment-emergent adverse events of any grade were nausea (169 [58%] of 289), anaemia (156 [54%]), and vomiting (111 [38%]); the most common grade 3 or worse events were haematological (anaemia in 95 [33%] of 289; thrombocytopenia in 47 [16%]; and neutropenia in 28 [10%]). Of 134 (46%) of 289 patients with at least one serious treatment-emergent adverse event, the most common were also haematological (thrombocytopenia in 17 [6%] and anaemia in 13 [4%]). Two adverse events with fatal outcome (one patient with urosepsis in the BRCA cohort and one patient with sepsis in the non-BRCA cohort) were deemed possibly related to niraparib treatment. Interpretation Niraparib is tolerable and shows anti-tumour activity in heavily pretreated patients with metastatic castration-resistant prostate cancer and DRDs, particularly in those with BRCA alterations

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    The diabetes-linked factorHMG20a targets islet genes involved in insulin secretion

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    Resumen del trabajo presentado al XXVIII Congreso Nacional de la Sociedad Española de diabetes, celebrado en Bilbao del 20 al 22 de abril de 2016.[Introduction and objectives]: Recent genome-wide association studies (GWAS) have identified HMG20A as a susceptibility locus for type 2 diabetes mellitus (T2DM). This gene encodes a factor that binds chromatin and exerts global genomic changes. Thus the role of HMG20A in the development and establishment of T2DM is far from evident. To assign a function to HMG20A in islet physiology, we aimed herein to: 1) Assess the expression levels of HMG20A in islets and whether acute or chronic exposure to glucose alters these levels and 2) determine the impact of HMG20A on glucose-stimulated insulin secretion (GSIS). [Material and methods]: HMG20A transcript levels were assessed by quantitative PCR (QT-PCR) in various tissues under basal or high glucose concentrations. Protein levels were also assessed by immunohistochemistry in islets. To evaluate the effect of HMG20A on beta cell function, expression levels of potential targets involved in insulin biosynthesis and secretion such as NEUROD, SNAP25, SYTVII, PI3K, Glucokinase (GK), GLUT-1 and GLUT-2 were measured following 72 hours of siRNA-mediated repression of HMG20A in MIN-6 and INS-1 cells. Data mining for HMG20A expression levels in both Type 1 (T1DM) and T2DM patients was performed using the Nextbio database from Illumina (www.nextbio.com). [Results]: High levels of HMG20A were detected in islets as compared to muscle and adipose tissue, whereas the transcript was more abundant in the liver. HMG20A protein was detected in mouse and human beta cells as well as in other islet cell types. Short-term exposure to glucose induced a transient increase in HMG20A transcript levels reaching a maximum of 2-fold at 72 hours in human islets with similar results in MIN-6 cells. However, expression of HMG20A was decreased in T2DM and T1DM patients as compared to non-diabetic subjects. siRNA-mediated repression of HMG20A in MIN-6 as well as in INS-1 cells resulted in decreased expression of NEUROD, INSULIN, and GK whereas PI3K and GLUT2 were increased. In parallel, GSIS was impaired following siRNA-mediated HMG20A repression in INS-1 cells. [Conclusions]: HMG20A modulates GSIS through regulation of metabolism-secretion coupling genes.This work is funded by the ISCIII (PI13/00593 to BG) and the Ministerio de Economía y Competitividad (JCI-2012-12491 to EFM).Peer Reviewe

    Protein-primed replication of bacteriophage phi 29 DNA.

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    The replication of phi 29 DNA-protein p3 represents a simple model system to study the protein-priming mechanism of initiation of replication. The phi 29 DNA polymerase involved both in the initiation and elongation steps of phi 29 DNA-protein p3 replication, is a very processive enzyme and it is able to produce strand-displacement in the absence of other proteins. To correlate functional and structural domains in the phi 29 DNA polymerase point mutants in the most carboxyl region of amino-acid homology with other DNA polymerases have been constructed. Most of the mutations had a decreased initiation and elongation activity, but normal 3'----5' exonuclease activity, suggesting that this region contributes to the active domain for initiation and elongation. Point and deletion mutants in the terminal protein have allowed the mapping of one DNA-binding region and two DNA-polymerase-binding regions. The viral protein p6, which stimulates the initiation of replication, binds to a set of specific signals present at both phi 29 DNA ends. A good correlation of binding and stimulation of replication has been obtained by using fragments containing phi 29 DNA-terminal sequences and deletion mutants of protein p6. The viral protein p5 has been shown to bind to single-stranded DNA, to protect the latter against nuclease digetion, and to stimulate phi 29 DNA-protein p3 replication in vitro.Peer reviewe

    The metabesity factor HMG20A potentiates astrocyte survival and reactive astrogliosis preserving neuronal integrity

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    Rationale: We recently demonstrated that the ‘Metabesity’ factor HMG20A regulates islet beta-cell functional maturity and adaptation to physiological stress such as pregnancy and pre-diabetes. HMG20A also dictates central nervous system (CNS) development via inhibition of the LSD1-CoREST complex but its expression pattern and function in adult brain remains unknown. Herein we sought to determine whether HMG20A is expressed in the adult CNS, specifically in hypothalamic astrocytes that are key in glucose homeostasis and whether similar to islets, HMG20A potentiates astrocyte function in response to environmental cues. Methods: HMG20A expression profile was assessed by quantitative PCR (QT-PCR), Western blotting and/or immunofluorescence in: 1) the hypothalamus of mice exposed or not to either a high-fat diet or a high-fat high-sucrose regimen, 2) human blood leukocytes and adipose tissue obtained from healthy or diabetic individuals and 3) primary mouse hypothalamic astrocytes exposed to either high glucose or palmitate. RNA-seq and cell metabolic parameters were performed on astrocytes treated or not with a siHMG20A. Astrocyte-mediated neuronal survival was evaluated using conditioned media from siHMG20A-treated astrocytes. The impact of ORY1001, an inhibitor of the LSD1-CoREST complex, on HMG20A expression, reactive astrogliosis and glucose metabolism was evaluated in vitro and in vivo in high-fat high-sucrose fed mice. Results: We show that Hmg20a is predominantly expressed in hypothalamic astrocytes, the main nutrient-sensing cell type of the brain. HMG20A expression was upregulated in diet-induced obesity and glucose intolerant mice, correlating with increased transcript levels of Gfap and Il1b indicative of inflammation and reactive astrogliosis. Hmg20a transcript levels were also increased in adipose tissue of obese non-diabetic individuals as compared to obese diabetic patients. HMG20A silencing in astrocytes resulted in repression of inflammatory, cholesterol biogenesis and epithelial-to-mesenchymal transition pathways which are hallmarks of reactive astrogliosis. Accordingly, HMG20A depleted astrocytes exhibited reduced mitochondrial bioenergetics and increased susceptibility to apoptosis. Neuron viability was also hindered in HMG20A-depleted astrocyte-derived conditioned media. ORY1001 treatment rescued expression of reactive astrogliosis-linked genes in HMG20A ablated astrocytes while enhancing cell surface area, GFAP intensity and STAT3 expression in healthy astrocytes, mimicking the effect of HMG20A. Furthermore, ORY1001 treatment protected against obesity-associated glucose intolerance in mice correlating with a regression of hypothalamic HMG20A expression, indicative of reactive astrogliosis attenuation with improved health status. Conclusion: HMG20A coordinates the astrocyte polarization state. Under physiological pressure such as obesity and insulin resistance that induces low grade inflammation, HMG20A expression is increased to induce reactive astrogliosis in an attempt to preserve the neuronal network and re-establish glucose homeostasis. Nonetheless, a chronic metabesity state or functional mutations will result in lower levels of HMG20A, failure to promote reactive astrogliosis and increase susceptibility of neurons to stress-induced apoptosis. Such effects could be reversed by ORY1001 treatment both in vitro and in vivo, paving the way for a new therapeutic approach for Type 2 Diabetes Mellitus

    Obesity-Induced Astrogliosis Is Regulated by the Diabesity Factor HMG20A

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    Resumen del trabajo presentado en el American Diabetes Association Meeting (2020), celebrado online del 12 al 16 de junio de 2020It is well established that systemic glucose homeostasis is imparted by an intricate cross-talk among several organs including the central nervous system (CNS) and pancreatic islets. In analogy to islet beta cells, hypothalamic astrocytes are glucose sensors that facilitate the CNS response to changing metabolic environment. Therefore, astrocytes and beta cells may share a common genetic signature implicated in coupling glucose metabolism to cellular output. We recently demonstrated that the diabesity factor HMG20A is essential for beta-cell functional maturity and adaptation to physiological stress (obesity, type 2 diabetes and pregnancy). As this chromatin remodelling factor also dictates CNS development, we sought to determine whether HMG20A is expressed in astrocytes and whether it potentiates astrocyte function in response to environmental cues. We found that HMG20A is expressed in hypothalamic astrocytes and is upregulated in diet-induced obesity and glucose-intolerant mice, correlating with increased transcript levels of GFAP and IL-1β, indicative of reactive astrocytes (astrogliosis). High glucose, but not lipids, transiently decreased HMG20A expression in isolated mouse primary astrocytes. HMG20A silencing in astrocytes resulted in repression of pro-inflammatory as well as lipid and glucose metabolism genes. These pathways are up-regulated in activated astrocytes (astrogliosis) to resolve stress conditions. As such astrocyte depleted of HMG20A were more susceptible to cell death. Furthermore, motor neuron viability in astrocyte conditioned media was significantly hindered after HMG20A depletion in astrocytes. We posit that HMG20A is involved in the astrocyte polarization state. Under physiological pressure such as obesity, HMG20A expression may be transiently decreased by high glucose but long-term it is increased to induce astrogliosis in an attempt to preserve the neuronal network and glucose homeostasis.ISCIII (PI13/00593 to B.R.G.), (PI13/00309 to F.J.B-S.); Ministerio de Economia y Competidividad/Fondos FEDER (PI10/00871, PI13/00593, BFU2017-83588-P to B.R.G.); BFU2017-85420-R (to J.C.R.); (JCI-2012-12491, IJCI-2015-26238 to E.F-M.); Consejería de Salud Junta de Andalucía (PI-0006-2016 to E.F-M.)Peer reviewe

    The metabesity factor HMG20A potentiates astrocyte survival and reactive astrogliosis preserving neuronal integrity

    No full text
    Rationale: We recently demonstrated that the 'Metabesity' factor HMG20A regulates islet beta-cell functional maturity and adaptation to physiological stress such as pregnancy and pre-diabetes. HMG20A also dictates central nervous system (CNS) development via inhibition of the LSD1-CoREST complex but its expression pattern and function in adult brain remains unknown. Herein we sought to determine whether HMG20A is expressed in the adult CNS, specifically in hypothalamic astrocytes that are key in glucose homeostasis and whether similar to islets, HMG20A potentiates astrocyte function in response to environmental cues. Methods: HMG20A expression profile was assessed by quantitative PCR (QT-PCR), Western blotting and/or immunofluorescence in: 1) the hypothalamus of mice exposed or not to either a high-fat diet or a high-fat high-sucrose regimen, 2) human blood leukocytes and adipose tissue obtained from healthy or diabetic individuals and 3) primary mouse hypothalamic astrocytes exposed to either high glucose or palmitate. RNA-seq and cell metabolic parameters were performed on astrocytes treated or not with a siHMG20A. Astrocyte-mediated neuronal survival was evaluated using conditioned media from siHMG20A-treated astrocytes. The impact of ORY1001, an inhibitor of the LSD1-CoREST complex, on HMG20A expression, reactive astrogliosis and glucose metabolism was evaluated in vitro and in vivo in high-fat high-sucrose fed mice. Results: We show that Hmg20a is predominantly expressed in hypothalamic astrocytes, the main nutrient-sensing cell type of the brain. HMG20A expression was upregulated in diet-induced obesity and glucose intolerant mice, correlating with increased transcript levels of Gfap and Il1b indicative of inflammation and reactive astrogliosis. Hmg20a transcript levels were also increased in adipose tissue of obese non-diabetic individuals as compared to obese diabetic patients. HMG20A silencing in astrocytes resulted in repression of inflammatory, cholesterol biogenesis and epithelial-to-mesenchymal transition pathways which are hallmarks of reactive astrogliosis. Accordingly, HMG20A depleted astrocytes exhibited reduced mitochondrial bioenergetics and increased susceptibility to apoptosis. Neuron viability was also hindered in HMG20A-depleted astrocyte-derived conditioned media. ORY1001 treatment rescued expression of reactive astrogliosis-linked genes in HMG20A ablated astrocytes while enhancing cell surface area, GFAP intensity and STAT3 expression in healthy astrocytes, mimicking the effect of HMG20A. Furthermore, ORY1001 treatment protected against obesity-associated glucose intolerance in mice correlating with a regression of hypothalamic HMG20A expression, indicative of reactive astrogliosis attenuation with improved health status. Conclusion: HMG20A coordinates the astrocyte polarization state. Under physiological pressure such as obesity and insulin resistance that induces low grade inflammation, HMG20A expression is increased to induce reactive astrogliosis in an attempt to preserve the neuronal network and re-establish glucose homeostasis. Nonetheless, a chronic metabesity state or functional mutations will result in lower levels of HMG20A, failure to promote reactive astrogliosis and increase susceptibility of neurons to stress-induced apoptosis. Such effects could be reversed by ORY1001 treatment both in vitro and in vivo, paving the way for a new therapeutic approach for Type 2 Diabetes Mellitus.The authors are supported by grants from the Consejería de Salud, Fundación Pública Andaluza Progreso y Salud, Junta de Andalucía (PI-0727-2010 and PI-0001-2020 to B.R.G.; PI-0085-2013 to P.I.L.; PI-0006-2016 to E.F.M.; PI-0574-2012 to S.Y.R.Z; PI-0247-2016 to F.J.B.S.), the Consejería de Economía, Innovación y Ciencia (P10.CTS.6359 to B.R.G.; CTS.8081 to E.G.F.), the Ministerio de Economía y Competitividad co-funded by Fondos FEDER (PI10/00871, PI13/00593 and BFU2017-83588-P to B.R.G.; PRE2018-084907 to M.E.M.V.G.; PI13/00309; PI17/01004 to F.J.B.S.; BFU2014-5343-P to J.C.R.; and AGL2017-86927-R to F.M.), Vencer el Cancer (B.R.G), DiabetesCero (B.R.G.) and the Juvenile Diabetes Research Foundation (17-2013-372 and 2-SRA-2019-837-S-B to B.R.G.). E.F.M. was a recipient of a Juan de la Cierva Incorporación Fellowship from the Ministerio de Economía y Competitividad (IJCI-2015-26238). S.Y.R.Z is a recipient of a postdoctoral fellowship from Consejería de Salud, Junta de Andalucía (RH-0070-2013). L.L.N. is supported by a Consejeria de Economia, Conocimiento, Empresas y Universidad postdoctoral fellowship (DOC_00652). F.J.B.S. and E.G.F. are recipients of "Nicolás Monardes" research contracts from Consejería de Salud Junta de Andalucía, (C-0070-2012 and C-0031-2016). A.M.M. is supported by CPII19/00023 and PI18/01590 from the Instituto de Salud Carlos III co-funded by Fondos FEDER. CIBERDEM is an initiative of the Instituto de Salud Carlos III. V.C. is supported by a AECC investigator award.Ye
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