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10 p.-10 fig.-5 tab.-1 graph. abst., Herein we present the evaluation of 11C-labeled-maleimides as radiotracers for positron emission tomography imaging of GSK-3 associated with Alzheimer′s disease (AD). 3-Acetyl-4-(1-[11C]-methyl-1H-indol-3-yl)[1H]pyrrole-2,5-dione ([11C]-2) was obtained by direct methylation using [11C]-CH3I and Cs2CO3 in DMF with a 31 ± 4% radiochemical yield and a radiochemical purity of 97.7 ± 0.8%. [11C]-2 was stable both in its final formulation and in human plasma for 120 min and had a plasma protein binding of 70 ± 1% and a LogD7.4 value of 1.84 ± 0.04. [11C]-2ex vivo biodistributions in healthy animals demonstrated significant brain uptake and retention, showing its ability to penetrate the intact blood–brain barrier. In vivo PET imaging in mice bearing AD showed, with respect to normal animals, significant differences in uptake in the hypothalamus, the striatum, and the amygdala and a significant increase in amygdala uptake in later stages of the pathology. These results are very promising, and further studies are being performed for a complete validation of this compound as novel tracer for AD., CSIC, Universidad de la República-Uruguay, PEDECIBA Química, and Agencia Nacional de Investigación e Innovación (ANII).

Based on a previously prepared lead compound, a new series of hybrid compounds was prepared and tested against six human tumour cell lines. These new triazole linked tetrahydropyran–oxazole hybrids were prepared evaluating the impact of the LogP for the proposed modifications. The compounds exhibited good antiproliferative results when compared with standards cisplatin and 5-fluorouracil. A series of triazole linked tetrahydropyran–oxazole hybrids was synthesized based on a previously reported lead compound with selective antiproliferative activity against human tumour cell lines. The series was prepared to evaluate the impact of LogP and different modifications in the activity, and the new compounds were assayed against A549, HBL-100, HeLa, SW1573, T-47D, and WiDr cell lines. Also, the potentiality to be P-gp substrate was tested. The compounds exhibited good antiproliferative results when compared with the standards cisplatin and 5-fluorouracil. In silico studies to evaluate pharmacokinetic properties using pkCSM software were also carried out.

This article belongs to the Special Issue Phytochemicals from Fruit and Vegetable By-Products and Wastes and Their Re-use., The present investigation aimed to provide novel information on the chemical composition and in vitro bioaccessibility of bioactive compounds from raw citrus pomaces (mandarin varieties Clemenule and Ortanique and orange varieties Navel and Valencia). The effects of the baking process on their bioaccessibility was also assessed. Samples of pomaces and biscuits containing them as an ingredient were digested, mimicking the human enzymatic oral gastrointestinal digestion process, and the composition of the digests were analyzed. UHPLC-MS/MS results of the citrus pomaces flavonoid composition showed nobiletin, hesperidin/neohesperidin, tangeretin, heptamethoxyflavone, tetramethylscutellarein, and naringin/narirutin. The analysis of the digests indicated the bioaccessibility of compounds possessing antioxidant [6.6–11.0 mg GAE/g digest, 65.5–97.1 µmol Trolox Equivalents (TE)/g digest, and 135.5–214.8 µmol TE/g digest for total phenol content (TPC), ABTS, and ORAC-FL methods, respectively; significant reduction (p < 0.05) in Reactive Oxygen Species (ROS) formation under tert-butyl hydroperoxide (1 mM)-induced conditions in IEC-6 and CCD-18Co cells when pre-treated with concentrations 5–25 µg/mL of the digests], anti-inflammatory [significant reduction (p < 0.05) in nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages], and antidiabetic (IC50 3.97–11.42 mg/mL and 58.04–105.68 mg/mL for α-glucosidase and α-amylase inhibition capacities) properties in the citrus pomaces under study. In addition, orange pomace biscuits with the nutrition claims “no-added sugars” and “source of fiber”, as well as those with good sensory quality (6.9–6.7, scale 1–9) and potential health promoting properties, were obtained. In conclusion, the results supported the feasibility of citrus pomace as a natural sustainable source of health-promoting compounds such as flavonoids. Unfractionated orange pomace may be employed as a functional food ingredient for reducing the risk of pathophysiological processes linked to oxidative stress, inflammation, and carbohydrate metabolism, such as diabetes, among others., This research was funded by ANII (grant POS_NAC_2016_1_130292), program EMHE-CSIC (grant MHE-200003), PEDECIBA-UdelaR, CSIC (project 201970E117) and Ministerio de Ciencia e Innovación (project PID2019-111510RB-I00).

Biocatalytic cascades afford the development of economically sustainable and green processes. Herein we examined the unprecedented coupling of co-immobilised Gluconobacter oxydans and an isolated transaminase to synthesise serinol from glycerol. Through this approach, we manufactured up to 36 mM serinol, the highest titer ever reported for a non-fermentative biosynthesis. More importantly, similar productivities are obtained starting from the industrial by-product crude glycerol, demonstrating the possibilities of this hybrid heterogenenous biocatalyst for valorising bio-based raw materials., S. Velasco acknowledges CONACyT for the granted postdoctoral fellowship. L. Betancor, E. Jackson and M. Ripoll acknowledge PEDECIBA, National Research and Innovation Agency of Uruguay (ANII) (POS_NAC_2019_1_158182) and Universidad ORT Uruguay. Fernando López acknowledges the funding of IKERBASQUE and Spanish Government (BIO2015-69887-R). This work was performed under the Maria de Maeztu Units of Excellence Programme – Grant No. MDM-2017-0720 Ministry of Science, Innovation and Universities.

Olive leaves (OL) are considered a potential source of bioactive compounds mainly due to its high content of phenolic compounds, widely known as natural antioxidants. The main objective of this study was to compare the performance of three OL extracts obtained by different extraction techniques in protecting canola oil against oxidative damage. The technologies evaluated were maceration with ethanol/water 75:25 (v/v), supercritical fluid extraction with CO2 (SC–CO2) and SC-CO2 with 10% ethanol as modifier (SC–CO2/EtOH). Each extract was analyzed as for total phenolic compounds (TPC), antioxidant activity (ABTS assay) and phenolic composition by reversed phase liquid chromatography-quadrupole-time of flight mass spectrometry. The oxidative stability of canola oil with or without the incorporation of 250 mg/kg of each extract was assessed during five weeks of storage at 60 °C. Peroxide, K232, K270, and Rancimat values, besides tocopherols content were determined. Macerated extract showed the highest TPC and antioxidant activity, but both SC-CO2 extracts were more effective in preserving tocopherols. In addition, SC-CO2 extracts delayed the oxidation progress as they lead to higher induction periods than control and macerated extracts, and a slower increase in peroxide values. Results obtained reinforce the use of supercritical fluid technology to obtain antioxidants compounds from natural sources., This work was funded by CSIC and ANII (Uruguay) with financial support and PEDECIBA-Química programs (Uruguay).

This article belongs to the Section Phytochemicals and Human Health., In the present work the feasibility of Tannat grape skin (TGS) as a functional ingredient in the formulation of two snacks (yogurt and biscuits) was studied. The research provided novel information on the effects of the food matrix and digestion process, under simulated human oral gastrointestinal conditions, in the bioaccessibility of TGS bioactive compounds composing of the snacks with health promoting properties (antioxidant, anti-inflammatory, and antidiabetic). TGS polyphenolic profile was analyzed by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) finding mainly flavonoids, phenolic acids, and anthocyanins, which may exert antioxidant, anti-inflammatory, and carbohydrase inhibition capacities. TGS digest showed antioxidant and antidiabetic potential compared to the undigested sample (p < 0.05). Yogurt and biscuits with TGS were developed with the nutrition claims “no-added sugars” and “source of fiber” and were digested in vitro to evaluate the bioaccessibility of compounds with health promoting properties after food processing and digestion. After in vitro simulation of digestion, bioactive properties were enhanced for control and TGS snacks which may be attributed to the formation/release of compounds with health-promoting properties. Biscuits showed significant increase in ABTS antioxidant capacity and yogurt showed increased α-glucosidase inhibition capacity by the addition of TGS (p < 0.05). Polyphenols from TGS and bioactive peptides from snacks which may be released during digestion might be responsible for the observed bioactivities. Consumer’s acceptance of TGS yogurt and biscuits showed scores of 6.3 and 5.1 (scale 1–9), respectively, showing TGS yogurt had higher overall acceptance. Sensory profile assessed by check-all-that-apply + just-about-right (CATA+JAR) showed most of the attributes were evaluated as “just about right”, supporting good food quality. The developed yogurt presented adequate shelf-life parameters for 28 days. TGS yogurt with higher acceptability showed reduced ROS formation (p < 0.05) induced by tert-butyl hydroperoxide (1 mM) in CCD-18Co colon cells and RAW264.7 macrophages when pre-treated with concentrations 500–1000 and 100–500 µg/mL of the digests, respectively. Moreover, TGS yogurt digest pre-treatment reduced nitric oxide (NO) production (p < 0.05) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages, showing anti-inflammatory potential. Bioactive peptides generated during lactic fermentation and digestion process may be contributors to intracellular effects. In conclusion, yogurt and biscuits with Tannat grape skin addition were obtained with nutrition claims “no-added sugars” and “source of fiber” with the potential to modulate key biochemical events associated with diabetes pathogenesis., This research was funded by Agencia Nacional de Investigación e Innovación (ANII, Uruguay) grant POS_NAC_2016_1_130292 and project FMV_3_2020_1_162341, Spanish National Research Council (CSIC, Spain) program EMHE-CSIC (grant MHE-200003) and project 201970E117, Ministry of Science and Innovation (Spain) project PID2019-111510RB-I00, as well as PEDECIBA-UdelaR.

International audience; We have previously shown that 5′ halves from tRNAGlyGCC and tRNAGluCUC are the most enriched small RNAs in the extracellular space of human cell lines, and especially in the non-vesicular fraction. Extracellular RNAs are believed to require protection by either encapsulation in vesicles or ribonucleoprotein complex formation. However, deproteinization of non-vesicular tRNA halves does not affect their retention in size-exclusion chromatography. Thus, we considered alternative explanations for their extracellular stability. In-silico analysis of the sequence of these tRNA-derived fragments showed that tRNAGly 5′ halves can form homodimers or heterodimers with tRNAGlu 5′ halves. This capacity is virtually unique to glycine tRNAs. By analyzing synthetic oligonucleotides by size exclusion chromatography, we provide evidence that dimerization is possible in vitro. tRNA halves with single point substitutions preventing dimerization are degraded faster both in controlled nuclease digestion assays and after transfection in cells, showing that dimerization can stabilize tRNA halves against the action of cellular nucleases. Finally, we give evidence supporting dimerization of endogenous tRNAGlyGCC 5′ halves inside cells. Considering recent reports have shown that 5′ tRNA halves from Ala and Cys can form tetramers, our results highlight RNA intermolecular structures as a new layer of complexity in the biology of tRNA-derived fragments.

Resumen del trabajo presentado al 6º Encuentro Nacional de Química (ENAQUI), celebrado en Montevideo (Uruguay) del 16 al 18 de octubre de 2019., Este trabajo fue financiado por ANII, CSIC (España) y PEDECIBA.

C-axis textured thin films of gallium-doped indium zinc oxide (GIZO) with a 2% ratio of Ga/Zn, were obtained via RF-magnetron sputtering with high transparency and electrical conductivity. A Box-Behnken response surface design was used to evaluate the effects of the deposition parameters (InO target power, deposition time, and substrate temperature) on the chemical composition, optical, electrical, and structural properties of the GIZO films. The optical constants and the electrical properties were obtained using optical models. The GIZO stoichiometry, and therefore the In/Zn atomic ratio, affected the crystallinity, crystalline parameters, band gap, and charge carrier mobility of the GIZO films. The charge carrier density was related to the change in the crystalline parameters of the hexagonal structure and the In/Zn atomic ratio. The best electrical conductivity values (1.75 × 10 Ω cm) were obtained for GIZO films with In/Zn ratio ≥ 1. Several figures of merit (FOM) defined for the visible and solar regions were comparatively used to select the optimal In/Zn atomic ratio that provided the best balance between the conductivity and the transparency. The optimal In/Zn ratio was in a range of 0.85–0.90 for the GIZO films., This work was supported by projects RNM1399 and TEC 2014-53906-R, Junta de Andalucía and Ministry of Economy and Competitiveness of Spain respectively. The authors are grateful to CSIC (Comisión Sectorial de Investigación Científica) of the Universidad de la República, in Montevideo, Uruguay, PEDECIBA- Física, ANII (Agencia Nacional de Investigación e Innovación), Uruguay; and to SCAI –Unidad de Nanotecnología of the University of Malaga. DII of PUCV (Pontifical Catholic University of Valparaiso) of Chile and FODECYT of Chile Grant no. 1160485, Chile, are also acknowledged.

Aim: To evaluate efficacy of sublingual flagellin to treat acute pneumonia. Materials & methods: Mice were treated sublingually with flagellin and challenged intranasally with a lethal dose of pneumococcus. Flagellins lacking TLR5 or NLRC4 activation domains were used to assess their contribution to protection. Results: Sublingual flagellin protected mice in a TLR5-dependent, NLRC4-independent fashion. Neutrophils were required for protection. Flagellin-stimulated lung epithelial cells recapitulated the lung's transcriptional profile suggesting they could be targeted by flagellin in vivo. Conclusion: Ligation of TLR5, a pathogen recognition receptor not naturally engaged by pneumococcus, protects mice from invasive pneumonia when administered via sublingual route. This can be a highly cost-effective alternative therapy against pneumonia.

24 pags., 10 figs., 1 tab., We investigate the consequences of the hybrid quantization approach for primordial perturbations in loop quantum cosmology, obtaining predictions for the cosmic microwave background and comparing them with data collected by the Planck mission. In this work, we complete previous studies about the scalar perturbations and incorporate tensor modes. We compute their power spectrum for a variety of vacuum states. We then analyze the tensor-to-scalar ratio and the consistency relation between this quantity and the spectral index of the tensor power spectrum. We also compute the temperature-temperature, electric-electric, temperature-electric, and magnetic-magnetic correlation functions. Finally, we discuss the effects of the quantum geometry in these correlation functions and confront them with observations., This work was supported by the Project. No. MINECO FIS2014-54800-C2-2-P from Spain. D. M-dB acknowledges financial support from the Project No. CONICYT/FONDECYT/POSTDOCTORADO/ 3140409 from Chile. J. O. was supported by the Project No. NSF-PHY-1305000, the Project No. PHY-1505411, the Eberly research funds of Penn State University (USA), and by Pedeciba (Uruguay).

International audience; Protein kinase G of Mycobacterium tuberculosis has been implicated in virulence and in regulation of glutamate metabolism. Here we show that this kinase undergoes a pattern of autophosphorylation that is distinct from that of other M. tuberculosis protein kinases characterized to date and we identify GarA as a substrate for phosphorylation by PknG. Autophosphorylation of PknG has little effect on kinase activity but promotes binding to GarA, an interaction that is also detected in living mycobacteria. PknG phosphorylates GarA at threonine 21, adjacent to the residue phosphorylated by PknB (T22), and these two phosphorylation events are mutually exclusive. Like the homologue OdhI from Corynebacterium glutamicum, the unphosphorylated form of GarA is shown to inhibit alpha-ketoglutarate decarboxylase in the TCA cycle. Additionally GarA is found to bind and modulate the activity of a large NAD(+)-specific glutamate dehydrogenase with an unusually low affinity for glutamate. Previous reports of a defect in glutamate metabolism caused by pknG deletion may thus be explained by the effect of unphosphorylated GarA on these two enzyme activities, which may also contribute to the attenuation of virulence.

Maternal behavior is species-specific and expressed under different physiological conditions, and contexts. It is the result of neural processes that support different forms (e.g. postpartum, cycling sensitized and spontaneous maternal behavior) and modalities of mother-offspring interaction (e.g. maternal interaction with altricial/precocious young; selective/non-selective bond). To understand how the brain adapts to and regulates maternal behavior in different species, and physiological and social conditions we propose new neural models to explain different forms of maternal expression (e.g. sensitized and spontaneous maternal behavior) and the behavioral changes that occur across the postpartum period. We emphasize the changing role of the medial preoptic area in the neural circuitry that supports maternal behavior and the cortical regulation and adjustment of ongoing behavioral performance. Finally, we discuss how our accumulated knowledge about the psychobiology of mothering in animal models supports the validity of animal studies to guide our understanding of human mothering and to improve human welfare and health.

International audience; Bacterial genomics revealed the widespread presence of eukaryotic-like protein kinases and phosphatases in prokaryotes, but little is known on their biochemical properties, regulation mechanisms and physiological roles. Here we focus on the catalytic domains of two trans-membrane enzymes, the Ser/Thr protein kinase PknB and the protein phosphatase PstP from Mycobacterium tuberculosis. PstP was found to specifically dephosphorylate model phospho-Ser/Thr substrates in a Mn2+-dependent manner. Autophosphorylated PknB was shown to be a substrate for Pstp and its kinase activity was affected by PstP-mediated dephosphorylation. Two threonine residues in the PknB activation loop, found to be mostly disordered in the crystal structure of this kinase, namely Thr171 and Thr173, were identified as the target for PknB autophosphorylation and PstP dephosphorylation. Replacement of these threonine residues by alanine significantly decreased the kinase activity, confirming their direct regulatory role. These results indicate that, as for eukaryotic homologues, phosphorylation of the activation loop provides a regulation mechanism of mycobacterial kinases and strongly suggest that PknB and PstP could work as a functional pair in vivo to control mycobacterial cell growth.

The PrnA transcriptional activator of Aspergillus nidulans binds as a dimer to CCGG-N-CCGG inverted repeats and to CCGG-6/7N-CCGG direct repeats. The binding specificity of the PrnA Zn cluster differs from that of the Gal4p/Ppr1p/UaY/Put3p group of proteins. Chimeras with UaY, a protein that strictly recognizes a CGG-6N-CCG motif, show that the recognition of the direct repeats necessitates the PrnA dimerization and linker elements, but the recognition of the CCGG-N-CCGG inverted repeats depends crucially on the PrnA Zn binuclear cluster and/or on residues amino-terminal to it. Three high-affinity sites in two different promoters have been visualized by in vivo methylation protection. Proline induction is essential for in vivo binding to these three sites but, as shown previously, not for nuclear entry. Simultaneous repression by ammonium and glucose does not affect in vivo binding to these high-affinity sites. PrnA differs from the isofunctional Saccharomyces cerevisiæ protein Put3p, both in its unique binding specificity and in the requirement of induction for in vivo DNA binding., Dennis Gómez was supported by a predoctoral scholarship from the French Ministère de l’Education Nationale, de l’Enseignement Supérieur et de la Recherche, a postdoctoral fellowship from ARC and European Union EUROFUNG contract no. BIO4-CT96-0535. Beatriz Cubero was supported by INRA and European Union contract BIO2CT930. Gianna Cecchetto was supported by CSSIC and Pedeciba Química. This work was supported by the CNRS, the Université Paris-Sud, the Institut Universitaire de France and European Union EUROFUNG contract (BIO4- CT96-0535).