139 results on '"Ana Luísa Carvalho"'
Search Results
2. Hierarchical self-assembly of a reflectin-derived peptide
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Ana Margarida Gonçalves Carvalho Dias, Inês Pimentel Moreira, Iana Lychko, Cátia Lopes Soares, Arianna Nurrito, Arménio Jorge Moura Barbosa, Viviane Lutz-Bueno, Raffaele Mezzenga, Ana Luísa Carvalho, Ana Sofia Pina, and Ana Cecília Afonso Roque
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supramolecular ,self-assembly ,peptides ,reflectins ,hydrogels ,films ,Chemistry ,QD1-999 - Abstract
Reflectins are a family of intrinsically disordered proteins involved in cephalopod camouflage, making them an interesting source for bioinspired optical materials. Understanding reflectin assembly into higher-order structures by standard biophysical methods enables the rational design of new materials, but it is difficult due to their low solubility. To address this challenge, we aim to understand the molecular self-assembly mechanism of reflectin’s basic unit—the protopeptide sequence YMDMSGYQ—as a means to understand reflectin’s assembly phenomena. Protopeptide self-assembly was triggered by different environmental cues, yielding supramolecular hydrogels, and characterized by experimental and theoretical methods. Protopeptide films were also prepared to assess optical properties. Our results support the hypothesis for the protopeptide aggregation model at an atomistic level, led by hydrophilic and hydrophobic interactions mediated by tyrosine residues. Protopeptide-derived films were optically active, presenting diffuse reflectance in the visible region of the light spectrum. Hence, these results contribute to a better understanding of the protopeptide structural assembly, crucial for the design of peptide- and reflectin-based functional materials.
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- 2023
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3. Evaluation of PIK3CA mutations in advanced ER+/HER2-breast cancer in Portugal – U-PIK Project
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Ana Peixoto, Luís Cirnes, Ana Luísa Carvalho, Maria João Andrade, Maria José Brito, Paula Borralho, Nuno Coimbra, Pedro M. Borralho, Ana Sofia Carneiro, Lisandra Castro, Lurdes Correia, Maria Rita Dionísio, Carlos Faria, Paulo Figueiredo, Ana Gomes, Joana Paixão, Manuela Pinheiro, Hugo Prazeres, Joana Ribeiro, Natália Salgueiro, Fernando C. Schmitt, Fátima Silva, Ana Rita Silvestre, Ana Carla Sousa, Joana Almeida-Tavares, Manuel R. Teixeira, Saudade André, and José Carlos Machado
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advanced breast cancer ,ER+/HER2− ,PIK3CA mutations ,ring trial ,validation ,molecular pathology ,Biology (General) ,QH301-705.5 - Abstract
Background: Around 40% of ER+/HER2-breast carcinomas (BC) present mutations in the PIK3CA gene. Assessment of PIK3CA mutational status is required to identify patients eligible for treatment with PI3Kα inhibitors, with alpelisib currently the only approved tyrosine kinase inhibitor in this setting. U-PIK project aimed to conduct a ring trial to validate and implement the PIK3CA mutation testing in several Portuguese centers, decentralizing it and optimizing its quality at national level.Methods: Eight Tester centers selected two samples of patients with advanced ER+/HER2- BC and generated eight replicates of each (n = 16). PIK3CA mutational status was assessed in two rounds. Six centers used the cobas®PIK3CA mutation test, and two used PCR and Sanger sequencing. In parallel, two reference centers (IPATIMUP and the Portuguese Institute of Oncology [IPO]-Porto) performed PIK3CA mutation testing by NGS in the two rounds. The quality of molecular reports describing the results was also assessed. Testing results and molecular reports were received and analyzed by U-PIK coordinators: IPATIMUP, IPO-Porto, and IPO-Lisboa.Results: Overall, five centers achieved a concordance rate with NGS results (allele frequency [AF] ≥5%) of 100%, one of 94%, one of 93%, and one of 87.5%, considering the overall performance in the two testing rounds. NGS reassessment of discrepancies in the results of the methods used by the Tester centers and the reference centers identified one probable false positive and two mutations with low AF (1–3%, at the analytical sensitivity threshold), interpreted as subclonal variants with heterogeneous representation in the tissue sections processed by the respective centers. The analysis of molecular reports revealed the need to implement the use of appropriate sequence variant nomenclature with the identification of reference sequences (HGVS-nomenclature) and to state the tumor cell content in each sample.Conclusion: The concordance rates between the method used by each tester center and NGS validate the use of the PIK3CA mutational status test performed at these centers in clinical practice in patients with advanced ER+/HER2- BC.
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- 2023
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4. Mycoplasma pneumoniae-Induced Rash and Mucositis: A Management Dilemma
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Margarida S. Abreu, Ana Luísa Carvalho, André Morais, Susana Carvalho, and Arnaldo Cerqueira
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Pediatrics ,RJ1-570 ,Medicine (General) ,R5-920 - Abstract
Mycoplasma pneumoniae induced rash and mucositis is a recently acknowledged clinical entity; therefore, the effectiveness and utility of therapeutic options are still under investigation. This case report aims to highlight the clinical characteristics of this disease and share a report on its management. Herein is reported a previously healthy 15-year-old male admitted with a high fever, severe oral and ocular mucositis, and scattered bullous lesions with an erythematous halo. The epidemiological context was irrelevant, and laboratory tests revealed elevated inflammatory markers. The patient received complete supportive care and intravenous immunoglobulin; however, there was no clinical or laboratory response. After the etiological investigation supported a Mycoplasma pneumoniae infection, treatment with azithromycin and systemic corticotherapy started, which led to favorable outcomes. He was discharged after 24 days with no sequelae. When Mycoplasma pneumoniae-induced rash and mucositis is suspected, extensive testing for mycoplasma infection should be granted and cautiously interpreted. Since disease management lacks robust scientific evidence, case reporting is significantly needed.
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- 2023
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5. The structure of a Bacteroides thetaiotaomicron carbohydrate-binding module provides new insight into the recognition of complex pectic polysaccharides by the human microbiome
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Filipa Trovão, Viviana G. Correia, Frederico M. Lourenço, Diana O. Ribeiro, Ana Luísa Carvalho, Angelina S. Palma, and Benedita A. Pinheiro
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Human gut microbiota ,Carbohydrates ,Rhamnogalacturonan II ,Carbohydrate binding module ,Bacteroides thetaiotaomicron ,Biology (General) ,QH301-705.5 - Abstract
The Bacteroides thetaiotaomicron has developed a consortium of enzymes capable of overcoming steric constraints and degrading, in a sequential manner, the complex rhamnogalacturonan II (RG-II) polysaccharide. BT0996 protein acts in the initial stages of the RG-II depolymerisation, where its two catalytic modules remove the terminal monosaccharides from RG-II side chains A and B. BT0996 is modular and has three putative carbohydrate-binding modules (CBMs) for which the roles in the RG-II degradation are unknown. Here, we present the characterisation of the module at the C-terminal domain, which we designated BT0996-C. The high-resolution structure obtained by X-ray crystallography reveals that the protein displays a typical β-sandwich fold with structural similarity to CBMs assigned to families 6 and 35. The distinctive features are: 1) the presence of several charged residues at the BT0996-C surface creating a large, broad positive lysine-rich patch that encompasses the putative binding site; and 2) the absence of the highly conserved binding-site signatures observed in CBMs from families 6 and 35, such as region A tryptophan and region C asparagine. These findings hint at a binding mode of BT0996-C not yet observed in its homologues. In line with this, carbohydrate microarrays and microscale thermophoresis show the ability of BT0996-C to bind α1-4-linked polygalacturonic acid, and that electrostatic interactions are essential for the recognition of the anionic polysaccharide. The results support the hypothesis that BT0996-C may have evolved to potentiate the action of BT0996 catalytic modules on the complex structure of RG-II by binding to the polygalacturonic acid backbone sequence.
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- 2023
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6. Design, development and deployment of a web-based interoperable registry for inherited retinal dystrophies in Portugal: the IRD-PT
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João Pedro Marques, Ana Luísa Carvalho, José Henriques, Joaquim Neto Murta, Jorge Saraiva, and Rufino Silva
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Inherited retinal dystrophies ,Registry ,Rare diseases ,Interoperability ,Software ,Data management ,Medicine - Abstract
Abstract Background The development of multicenter patient registries promotes the generation of scientific knowledge by using real-world data. A country-wide, web-based registry for inherited retinal dystrophies (IRDs) empowers patients and community organizations, while supporting formal partnerships research. We aim to describe the design, development and deployment of a country-wide, with investigators and stakeholders in the global aim to develop high-value, high-utility web-based, user-friendly and interoperable registry for IRDs—the IRD-PT. Results The IRD-PT is a clinical/genetic research registry included in the retina.pt platform ( https://www.retina.com.pt ), which was developed by the Portuguese Retina Study Group. The retina.pt platform collects data on individuals diagnosed with retinal diseases, from several sites across Portugal, with over 1800 participants and over 30,000 consultations to date. The IRD-PT module interacts with the retina.pt core system which provides a range of basic functions for patient data management, while the IRD-PT module allows data capture for the specific purpose of IRDs. All IRDs are coded accordingly to the International Statistical Classification of Diseases and Related Health Problems (ICD) 9, ICD 10, ICD 11, and Orphanet Rare Disease Ontology (ORPHA codes) to make the IRD-PT interoperable with other IRD registries across the world. Furthermore, the genes are coded according to the Ontology of Genes and Genomes and Online Mendelian Inheritance in Man, whereas signs and symptoms are coded according to the Human Phenotype Ontology. The IRD-PT module pre-launched at Centro Hospitalar e Universitário de Coimbra, the largest reference center for IRDs in Portugal. As of April 1st 2020, finalized data from 537 participants were available for this preliminary analysis. Conclusions In the specific field of rare diseases, the use of registries increases research accessibility for individuals, while providing clinicians/investigators with a coherent data ecosystem necessary to boost research. Appropriate design and implementation of patient registries enables rapid decision making and ongoing data mining, ultimately leading to improved patient outcomes. We have described here the principles behind the design, development and deployment of a web-based, user-friendly and interoperable software tool aimed to generate important knowledge and collecting high-quality data on the epidemiology, genomic landscape and natural history of IRDs in Portugal.
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- 2020
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7. Mapping Molecular Recognition of β1,3-1,4-Glucans by a Surface Glycan-Binding Protein from the Human Gut Symbiont Bacteroides ovatus
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Viviana G. Correia, Filipa Trovão, Benedita A. Pinheiro, Joana L. A. Brás, Lisete M. Silva, Cláudia Nunes, Manuel A. Coimbra, Yan Liu, Ten Feizi, Carlos M. G. A. Fontes, Barbara Mulloy, Wengang Chai, Ana Luísa Carvalho, and Angelina S. Palma
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β-glucan ,Bacteroides ovatus ,carbohydrate microarrays ,polysaccharide utilization loci ,protein-carbohydrate interactions ,SusD-like proteins ,Microbiology ,QR1-502 - Abstract
ABSTRACT A multigene polysaccharide utilization locus (PUL) encoding enzymes and surface carbohydrate (glycan)-binding proteins (SGBPs) was recently identified in prominent members of Bacteroidetes in the human gut and characterized in Bacteroides ovatus. This PUL-encoded system specifically targets mixed-linkage β1,3-1,4-glucans, a group of diet-derived carbohydrates that promote a healthy microbiota and have potential as prebiotics. The BoSGBPMLG-A protein encoded by the BACOVA_2743 gene is a SusD-like protein that plays a key role in the PUL’s specificity and functionality. Here, we perform a detailed analysis of the molecular determinants underlying carbohydrate binding by BoSGBPMLG-A, combining carbohydrate microarray technology with quantitative affinity studies and a high-resolution X-ray crystallography structure of the complex of BoSGBPMLG-A with a β1,3-1,4-nonasaccharide. We demonstrate its unique binding specificity toward β1,3-1,4-gluco-oligosaccharides, with increasing binding affinities up to the octasaccharide and dependency on the number and position of β1,3 linkages. The interaction is defined by a 41-Å-long extended binding site that accommodates the oligosaccharide in a mode distinct from that of previously described bacterial β1,3-1,4-glucan-binding proteins. In addition to the shape complementarity mediated by CH-π interactions, a complex hydrogen bonding network complemented by a high number of key ordered water molecules establishes additional specific interactions with the oligosaccharide. These support the twisted conformation of the β-glucan backbone imposed by the β1,3 linkages and explain the dependency on the oligosaccharide chain length. We propose that the specificity of the PUL conferred by BoSGBPMLG-A to import long β1,3-1,4-glucan oligosaccharides to the bacterial periplasm allows Bacteroidetes to outcompete bacteria that lack this PUL for utilization of β1,3-1,4-glucans. IMPORTANCE With the knowledge of bacterial gene systems encoding proteins that target dietary carbohydrates as a source of nutrients and their importance for human health, major efforts are being made to understand carbohydrate recognition by various commensal bacteria. Here, we describe an integrative strategy that combines carbohydrate microarray technology with structural studies to further elucidate the molecular determinants of carbohydrate recognition by BoSGBPMLG-A, a key protein expressed at the surface of Bacteroides ovatus for utilization of mixed-linkage β1,3-1,4-glucans. We have mapped at high resolution interactions that occur at the binding site of BoSGBPMLG-A and provide evidence for the role of key water-mediated interactions for fine specificity and affinity. Understanding at the molecular level how commensal bacteria, such as prominent members of Bacteroidetes, can differentially utilize dietary carbohydrates with potential prebiotic activities will shed light on possible ways to modulate the microbiome to promote human health.
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- 2021
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8. Higher order scaffoldin assembly in Ruminococcus flavefaciens cellulosome is coordinated by a discrete cohesin-dockerin interaction
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Pedro Bule, Virgínia M. R. Pires, Victor D. Alves, Ana Luísa Carvalho, José A. M. Prates, Luís M. A. Ferreira, Steven P. Smith, Harry J. Gilbert, Ilit Noach, Edward A. Bayer, Shabir Najmudin, and Carlos M. G. A. Fontes
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Medicine ,Science - Abstract
Abstract Cellulosomes are highly sophisticated molecular nanomachines that participate in the deconstruction of complex polysaccharides, notably cellulose and hemicellulose. Cellulosomal assembly is orchestrated by the interaction of enzyme-borne dockerin (Doc) modules to tandem cohesin (Coh) modules of a non-catalytic primary scaffoldin. In some cases, as exemplified by the cellulosome of the major cellulolytic ruminal bacterium Ruminococcus flavefaciens, primary scaffoldins bind to adaptor scaffoldins that further interact with the cell surface via anchoring scaffoldins, thereby increasing cellulosome complexity. Here we elucidate the structure of the unique Doc of R. flavefaciens FD-1 primary scaffoldin ScaA, bound to Coh 5 of the adaptor scaffoldin ScaB. The RfCohScaB5-DocScaA complex has an elliptical architecture similar to previously described complexes from a variety of ecological niches. ScaA Doc presents a single-binding mode, analogous to that described for the other two Coh-Doc specificities required for cellulosome assembly in R. flavefaciens. The exclusive reliance on a single-mode of Coh recognition contrasts with the majority of cellulosomes from other bacterial species described to date, where Docs contain two similar Coh-binding interfaces promoting a dual-binding mode. The discrete Coh-Doc interactions observed in ruminal cellulosomes suggest an adaptation to the exquisite properties of the rumen environment.
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- 2018
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9. The Role of Ghrelin in Regulating Synaptic Function and Plasticity of Feeding-Associated Circuits
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Débora Serrenho, Sandra D. Santos, and Ana Luísa Carvalho
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ghrelin ,synaptic plasticity ,hypothalamus ,ventral tegmental area ,hippocampus ,feeding ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Synaptic plasticity of the neuronal circuits associated with feeding behavior is regulated by peripheral signals as a response to changes in the energy status of the body. These signals include glucose, free fatty acids, leptin and ghrelin and are released into circulation, being able to reach the brain. Ghrelin, a small peptide released from the stomach, is an orexigenic hormone produced in peripheral organs, and its action regulates food intake, body weight and glucose homeostasis. Behavioral studies show that ghrelin is implicated in the regulation of both hedonic and homeostatic feeding and of cognition. Ghrelin-induced synaptic plasticity has been described in neuronal circuits associated with these behaviors. In this review, we discuss the neuromodulatory mechanisms induced by ghrelin in regulating synaptic plasticity in three main neuronal circuits previously associated with feeding behaviors, namely hypothalamic (homeostatic feeding), ventral tegmental (hedonic and motivational feeding) and hippocampal (cognitive) circuits. Given the central role of ghrelin in regulating feeding behaviors, and the altered ghrelin levels associated with metabolic disorders such as obesity and anorexia, it is of paramount relevance to understand the effects of ghrelin on synaptic plasticity of neuronal circuits associated with feeding behaviors.
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- 2019
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10. Multiple domains in the C-terminus of NMDA receptor GluN2B subunit contribute to neuronal death following in vitro ischemia
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Marta M. Vieira, Jeannette Schmidt, Joana S. Ferreira, Kevin She, Shinichiro Oku, Miranda Mele, Armanda E. Santos, Carlos B. Duarte, Ann Marie Craig, and Ana Luísa Carvalho
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AP2 ,CaMKIIα ,Cerebral ischemia ,GluN2B ,Oxygen-glucose deprivation ,NMDA receptors ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Global cerebral ischemia induces selective degeneration of specific subsets of neurons throughout the brain, particularly in the hippocampus and cortex. One of the major hallmarks of cerebral ischemia is excitotoxicity, characterized by overactivation of glutamate receptors leading to intracellular Ca2+ overload and ultimately neuronal demise. N-methyl-d-aspartate receptors (NMDARs) are considered to be largely responsible for excitotoxic injury due to their high Ca2+ permeability. In the hippocampus and cortex, these receptors are most prominently composed of combinations of two GluN1 subunits and two GluN2A and/or GluN2B subunits. Due to the controversy regarding the differential role of GluN2A and GluN2B subunits in excitotoxic cell death, we investigated the role of GluN2B in the activation of pro-death signaling following an in vitro model of global ischemia, oxygen and glucose deprivation (OGD). For this purpose, we used GluN2B−/− mouse cortical cultures and observed that OGD-induced damage was reduced in these neurons, and partially prevented in wild-type rat neurons by a selective GluN2B antagonist. Notably, we found a crucial role of the C-terminal domain of the GluN2B subunit in triggering excitotoxic signaling. Indeed, expression of YFP–GluN2B C-terminus mutants for the binding sites to post-synaptic density protein 95 (PSD95), Ca2+-calmodulin kinase IIα (CaMKIIα) or clathrin adaptor protein 2 (AP2) failed to mediate neuronal death in OGD conditions. We focused on the GluN2B–CaMKIIα interaction and found a determinant role of this interaction in OGD-induced death. Inhibition or knock-down of CaMKIIα exerted a neuroprotective effect against OGD-induced death, whereas overexpression of this kinase had a detrimental effect. Importantly, in comparison with neurons overexpressing wild-type CaMKIIα, neurons overexpressing a mutant form of the kinase (CaMKII-I205K), unable to interact with GluN2B, were partially protected against OGD-induced damage. Taken together, our results identify crucial determinants in the C-terminal domain of GluN2B subunits in promoting neuronal death in ischemic conditions. These mechanisms underlie the divergent roles of the GluN2A- and GluN2B–NMDARs in determining neuronal fate in cerebral ischemia.
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- 2016
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11. Stargazin Dephosphorylation Mediates Homeostatic Synaptic Downscaling of Excitatory Synapses
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Susana R. Louros, Gladys L. Caldeira, and Ana Luísa Carvalho
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homeostatic plasticity ,stargazin ,AMPA receptors ,synaptic downscaling ,membrane trafficking ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Synaptic scaling is a form of homeostatic plasticity that is critical for maintaining neuronal activity within a dynamic range, and which alters synaptic strength through changes in postsynaptic AMPA-type glutamate receptors. Homeostatic scaling down of excitatory synapses has been shown to occur during sleep, and to contribute to synapse remodeling and memory consolidation, but the underlying mechanisms are only partially known. Here, we report that synaptic downscaling in cortical neurons is accompanied by dephosphorylation of the transmembrane AMPA receptor regulatory protein stargazin, and by an increase in its cell surface mobility. The changes in stargazin surface diffusion were paralleled by an increase in the mobility of GluA1-containing AMPA receptors at synaptic sites. In addition, stargazin dephosphorylation was required for the downregulation of surface levels of GluA1-containing AMPA receptors promoted by chronic elevation of neuronal activity, specifically by mediating the interaction with the adaptor proteins AP-2 and AP-3A. Disruption of the stargazin-AP-3A interaction was sufficient to prevent the decrease in cell surface GluA1-AMPA receptor levels associated with chronically enhanced synaptic activity, suggesting that scaling down is accomplished through decreased AMPA receptor recycling and enhanced lysosomal degradation. Thus, synaptic downscaling is associated with both increased stargazin and AMPA receptor cell surface diffusion, as well as with stargazin-mediated AMPA receptor endocytosis and lysosomal degradation.
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- 2018
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12. Cleavage of the vesicular glutamate transporters under excitotoxic conditions
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Andrea C. Lobo, João R. Gomes, Tatiana Catarino, Miranda Mele, Pedro Fernandez, Ana R. Inácio, Ben A. Bahr, Armanda E. Santos, Tadeusz Wieloch, Ana Luísa Carvalho, and Carlos B. Duarte
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Brain ischemia ,Calpains ,Excitotoxicity ,Oxygen and glucose deprivation ,Vesicular glutamate transporters ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Glutamate is loaded into synaptic vesicles by vesicular glutamate transporters (VGLUTs), and alterations in the transporters expression directly regulate neurotransmitter release. We investigated changes in VGLUT1 and VGLUT2 protein levels after ischemic and excitotoxic insults. The results show that VGLUT2 is cleaved by calpains after excitotoxic stimulation of hippocampal neurons with glutamate, whereas VGLUT1 is downregulated to a lower extent. VGLUT2 was also cleaved by calpains after oxygen/glucose deprivation (OGD), and downregulated after middle cerebral artery occlusion (MCAO) and intrahippocampal injection of kainate. In contrast, VGLUT1 was not affected after OGD. Incubation of isolated synaptic vesicles with recombinant calpain also induced VGLUT2 cleavage, with a little effect observed for VGLUT1. N-terminal sequencing analysis showed that calpain cleaves VGLUT2 in the C-terminus, at Asn534 and Lys542. The truncated GFP-VGLUT2 forms were found to a great extent in non-synaptic regions along neurites, when compared to GFP-VGLUT2. These findings show that excitotoxic and ischemic insults downregulate VGLUT2, which is likely to affect glutamatergic transmission and cell death, especially in the neonatal period when the transporter is expressed at higher levels.
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- 2011
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13. In vitro ischemia triggers a transcriptional response to down-regulate synaptic proteins in hippocampal neurons.
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Joana Fernandes, Marta Vieira, Laura Carreto, Manuel A S Santos, Carlos B Duarte, Ana Luísa Carvalho, and Armanda E Santos
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Medicine ,Science - Abstract
Transient global cerebral ischemia induces profound changes in the transcriptome of brain cells, which is partially associated with the induction or repression of genes that influence the ischemic response. However, the mechanisms responsible for the selective vulnerability of hippocampal neurons to global ischemia remain to be clarified. To identify molecular changes elicited by ischemic insults, we subjected hippocampal primary cultures to oxygen-glucose deprivation (OGD), an in vitro model for global ischemia that resulted in delayed neuronal death with an excitotoxic component. To investigate changes in the transcriptome of hippocampal neurons submitted to OGD, total RNA was extracted at early (7 h) and delayed (24 h) time points after OGD and used in a whole-genome RNA microarray. We observed that at 7 h after OGD there was a general repression of genes, whereas at 24 h there was a general induction of gene expression. Genes related with functions such as transcription and RNA biosynthesis were highly regulated at both periods of incubation after OGD, confirming that the response to ischemia is a dynamic and coordinated process. Our analysis showed that genes for synaptic proteins, such as those encoding for PICK1, GRIP1, TARPγ3, calsyntenin-2/3, SAPAP2 and SNAP-25, were down-regulated after OGD. Additionally, OGD decreased the mRNA and protein expression levels of the GluA1 AMPA receptor subunit as well as the GluN2A and GluN2B subunits of NMDA receptors, but increased the mRNA expression of the GluN3A subunit, thus altering the composition of ionotropic glutamate receptors in hippocampal neurons. Together, our results present the expression profile elicited by in vitro ischemia in hippocampal neurons, and indicate that OGD activates a transcriptional program leading to down-regulation in the expression of genes coding for synaptic proteins, suggesting that the synaptic proteome may change after ischemia.
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- 2014
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14. Nucleocytoplasmic shuttling activity of ataxin-3.
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Sandra Macedo-Ribeiro, Luísa Cortes, Patrícia Maciel, and Ana Luísa Carvalho
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Medicine ,Science - Abstract
Spinocerebellar ataxia type-3, also known as Machado-Joseph Disease (MJD), is one of many inherited neurodegenerative disorders caused by polyglutamine-encoding CAG repeat expansions in otherwise unrelated genes. Disease protein misfolding and aggregation, often within the nucleus of affected neurons, characterize polyglutamine disorders. Several evidences have implicated the nucleus as the primary site of pathogenesis for MJD. However, the molecular determinants for the nucleocytoplasmic transport of human ataxin-3 (Atx3), the protein which is mutated in patients with MJD, are not characterized. In order to characterize the nuclear shuttling activity of Atx3, we performed yeast nuclear import assays and found that Atx3 is actively imported into the nucleus, by means of a classical nuclear localizing sequence formed by a cluster of lysine and arginine residues. On the other hand, when active nuclear export was inhibited using leptomycin B, a specific inhibitor of the nuclear export receptor CRM1, both endogenous Atx3 and transfected GFP-Atx3 accumulated inside the nucleus of a subpopulation of COS-7 cells, whereas both proteins are normally predominant in the cytoplasm. Additionally, using a Rev(1.4)-GFP nuclear export assay, we performed an extensive analysis of six putative aliphatic nuclear export motifs identified in Atx3 amino acid sequence. Although none of the tested peptide sequences were found to drive nuclear export when isolated, we have successfully mapped the region of Atx3 responsible for its CRM1-independent nuclear export activity. Curiously, the N-terminal Josephin domain alone is exported into the cytoplasm, but the nuclear export activity of Atx3 is significantly enhanced in a longer construct that is truncated after the two ubiquitin interaction motifs, upstream from the polyQ tract. Our data show that Atx3 is actively imported to and exported from the cell nucleus, and that its nuclear export activity is dependent on a motif located at its N-terminal region. Since pathological Atx3 aggregates in the nucleus of affected neurons in MJD, and there is in vivo evidence that nuclear localization of Atx3 is required for the manifestation of symptoms in MJD, defects in the nucleocytoplasmic shuttling activity of the protein may be involved in the nuclear accumulation and aggregation of expanded Atx3.
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- 2009
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15. PIBID de língua portuguesa na educação de jovens e adultos: Um olhar para a desigualdade de gênero
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Gonçalves do Ó, Jeniffer, primary, Rodrigues, Ana Luísa Carvalho, additional, and Nazário, Maria de Lurdes, additional
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- 2023
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16. Faecalibacterium prausnitzii in Differentiated Thyroid Cancer Patients Treated with Radioiodine
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Barata, Ana Fernandes, Ana Oliveira, Ana Luísa Carvalho, Raquel Soares, and Pedro
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Faecalibacterium prausnitzii ,thyroid cancer ,radioiodine therapy ,gut microbiota ,metagenomic sequencing - Abstract
Background: Faecalibacterium prausnitzii, one of the most important bacteria of the human gut microbiota, produces butyrate (a short-chain fatty acid). Short-chain fatty acids are known to influence thyroid physiology and thyroid cancer’s response to treatment. We aimed to analyze the relative abundance of Faecalibacterium prausnitzii on the gut microbiota of differentiated thyroid cancer patients compared to controls and its variation after radioiodine therapy (RAIT). Methods: Fecal samples were collected from 37 patients diagnosed with differentiated thyroid cancer before and after radioiodine therapy and from 10 volunteers. The abundance of F. prausnitzii was determined using shotgun metagenomics. Results: Our study found that the relative abundance of F. prausnitzii is significantly reduced in thyroid cancer patients compared to volunteers. We also found that there was a mixed response to RAIT, with an increase in the relative and absolute abundances of this bacterium in most patients. Conclusions: Our study confirms that thyroid cancer patients present a dysbiotic gut microbiota, with a reduction in F. prausnitzii’s relative abundance. In our study, radioiodine did not negatively affect F. prausnitzii, quite the opposite, suggesting that this bacterium might play a role in resolving radiation aggression issues.
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- 2023
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17. Aberrant hippocampal transmission and behavior in mice with a stargazin mutation linked to intellectual disability
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Gladys L. Caldeira, R. P. Gouveia, Carlos A. V. Barreto, João Peça, Mohamed Edfawy, Ana Luísa Carvalho, Nuno Beltrão, A. S. Inacio, Joana R. Guedes, R. Macedo, B. Cruz, Susana R. Louros, Irina S. Moreira, Tiago Rondão, and M. V. Rodrigues
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Mutation ,Hippocampus ,AMPA receptor ,Hippocampal formation ,Neurotransmission ,Biology ,medicine.disease_cause ,Transmembrane protein ,Cellular and Molecular Neuroscience ,Psychiatry and Mental health ,Excitatory synapse ,medicine ,Receptor ,Neuroscience ,Molecular Biology - Abstract
Mutations linked to neurodevelopmental disorders, such as intellectual disability (ID), are frequently found in genes that encode for proteins of the excitatory synapse. Transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary proteins that regulate crucial aspects of receptor function. Here, we investigate a mutant form of the TARP family member stargazin, described in an ID patient. Molecular dynamics analyses predicted that the ID-associated stargazin variant, V143L, weakens the overall interface of the AMPAR:stargazin complex and impairs the stability of the complex. Knock-in mice harboring the V143L stargazin mutation manifest cognitive and social deficits and hippocampal synaptic transmission defects, resembling phenotypes displayed by ID patients. In the hippocampus of stargazin V143L mice, CA1 neurons show impaired spine maturation, abnormal synaptic transmission and long-term potentiation specifically in basal dendrites, and synaptic ultrastructural alterations. These data suggest a causal role for mutated stargazin in the pathogenesis of ID and unveil a new role for stargazin in the development and function of hippocampal synapses. This work was supported by a NARSAD Independent Investigator Grant (#23151) and a NARSAD Young Investigator Grant (#20733) from the Brain and Behavior Research Foundation, by a research grant from the Jérôme Lejeune Foundation (#1530), by “la Caixa” Foundation (ID 100010434), and FCT, I.P under the project code LCF/PR/HP20/52300003, by a Marie Curie Integration Grant (618525), by a Bial Foundation Grant (266/2016), by national funds through the Portuguese Science and Technology Foundation (FCT: UID/NEU/04539/2013, UIDB/04539/2020, POCI-01-0145-FEDER-28541, POCI-01-0145-FEDER-016682, PTDC/QUI-OUT/32243/2017 and CPCA/A0/7302/2020), and by the European Regional Development Fund (ERDF), through the Centro 2020 Regional Operational Programme, under project CENTRO-01-0145-FEDER-000008:BrainHealth 2020. GLC, NB, MVR, ME and CAVB were supported by FCT through Ph.D. scholarships SFRH/BD/51962/2012, SFRH/BD/144881/2019, SFRH/BD/129236/2017, SFRH/BD/51958/2012 and SFRH/BD/145457/2019, respectively. ASI and JG were supported by FCT through Postdoctoral fellowship SFRH/BPD122299/2016 and SFRH/BPD/120611/2016, respectively. RPG and RM received support from FCT/DGES, under the program “Verão com Ciência”.
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- 2022
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18. Narrativas Visuais para Educação e Aprendizagem: estudo de prospecção científica e tecnológica
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Ana Luísa Carvalho Soletti, Sandra Helena Vieira de Carvalho, and Sílvia Beatriz Beger Uchôa
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General Medicine - Abstract
Este trabalho apresenta uma revisão bibliográfica e patentária referente ao uso da narrativa visual aplicada ao ensino e à aprendizagem. A pesquisa tem caráter qualitativo e quantitativo, de forma a se obter resultados aprofundados e abrangentes. Foram utilizadas as plataformas Scopus e Web of Science para o levantamento bibliográfico. Para o levantamento patentário, a busca foi realizada nas bases Orbit®, Esp@cenet e INPI. A pesquisa mostrou que a abordagem da narrativa visual aplicada à educação vem ganhando espaço na área acadêmica, com diversos estudos que abrangem seu entendimento como ferramenta inovadora, adotando diferentes mídias e tecnologias. Essa abordagem facilita a compreensão e acessibilidade de diversos assuntos, em diferentes áreas do conhecimento, podendo ser aplicada a diferentes públicos, sendo também um possível canal de inclusão de indivíduos com diferentes tipos de limitações.
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- 2022
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19. Structural Characterization of Neisseria gonorrhoeae Bacterial Peroxidase—Insights into the Catalytic Cycle of Bacterial Peroxidases
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Cláudia S. Nóbrega, Ana Luísa Carvalho, Maria João Romão, Sofia R. Pauleta, UCIBIO - Applied Molecular Biosciences Unit, and DQ - Departamento de Química
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Bacterial peroxidase ,Agricultural and Biological Sciences(all) ,Organic Chemistry ,pathogenic bacteria ,General Medicine ,Catalysis ,Neisseria gonorrhoeae ,inhibition ,Computer Science Applications ,Inorganic Chemistry ,SDG 3 - Good Health and Well-being ,Physical and Theoretical Chemistry ,Molecular Biology ,Spectroscopy ,bacterial peroxidase ,active state ,azide-inhibited structure ,ROS detoxification ,catalytic cycle ,diheme enzymes - Abstract
This research was funded by the Fundação para a Ciência e Tecnologia, I.P. (FCT), through project grants to S.R.P. (PTDC/BIA-PRO/109796/2009 and PTDC/BIA-BQM/29442/2017) and A.L.C. (RECI/BBB-BEP/0124/2012), and scholarship to C.S.N. (SFRH/BD/87878/2012). This work was also supported by national funds from the FCT within the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences—UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB. Acknowledgments The authors would like to thank Lina Juknaité for her contribution in the initial crystallization studies. The authors acknowledge the European Synchrotron Radiation Facility and the Swiss Light Source for provision of synchrotron radiation facilities and access to beamlines BM30 and PXIII (X06DA), respectively. Neisseria gonorrhoeae is an obligate human pathogenic bacterium responsible for gonorrhea, a sexually transmitted disease. The bacterial peroxidase, an enzyme present in the periplasm of this bacterium, detoxifies the cells against hydrogen peroxide and constitutes one of the primary defenses against exogenous and endogenous oxidative stress in this organism. The 38 kDa heterologously produced bacterial peroxidase was crystallized in the mixed-valence state, the active state, at pH 6.0, and the crystals were soaked with azide, producing the first azide-inhibited structure of this family of enzymes. The enzyme binds exogenous ligands such as cyanide and azide, which also inhibit the catalytic activity by coordinating the P heme iron, the active site, and competing with its substrate, hydrogen peroxide. The inhibition constants were estimated to be 0.4 ± 0.1 µM and 41 ± 5 mM for cyanide and azide, respectively. Imidazole also binds and inhibits the enzyme in a more complex mechanism by binding to P and E hemes, which changes the reduction potential of the latest heme. Based on the structures now reported, the catalytic cycle of bacterial peroxidases is revisited. The inhibition studies and the crystal structure of the inhibited enzyme comprise the first platform to search and develop inhibitors that target this enzyme as a possible new strategy against N. gonorrhoeae. publishersversion published
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- 2023
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20. Bilateral functional worsening following voretigene neparvovec therapy
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Emmanuel Rebelo Neves, Ana Luísa Carvalho, Teresa Mesquita, Catarina Paiva, Mário Alfaiate, João Figueira, Joaquim Murta, and João Pedro Marques
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Ophthalmology - Published
- 2023
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21. Eyes Shut Homolog-Associated Retinal Degeneration
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Ricardo Machado Soares, Ana Luísa Carvalho, Sílvia Simão, Célia Azevedo Soares, Miguel Raimundo, C Henrique Alves, António Francisco Ambrósio, Joaquim Murta, Jorge Saraiva, Rufino Silva, and João Pedro Marques
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Ophthalmology - Published
- 2023
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22. Seasonal variation of understory insectivorous birds and arthropods in an area of secondary Atlantic Forest, southeast Brazil
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de Lima, Ana Luísa Carvalho and Manhães, Marco Antônio
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- 2017
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23. Structure-function studies can improve binding affinity of cohesin-dockerin interactions for multi-protein assemblies
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Marlene Duarte, Victor D. Alves, Márcia Correia, Catarina Caseiro, Luís M.A. Ferreira, Maria João Romão, Ana Luísa Carvalho, Shabir Najmudin, Edward A. Bayer, Carlos M.G.A. Fontes, Pedro Bule, UCIBIO - Applied Molecular Biosciences Unit, and DQ - Departamento de Química
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Cohesin ,Structural Biology ,Carbohydrates ,Protein complex ,Dockerin ,General Medicine ,Molecular Biology ,Biochemistry ,Biomass degradation ,Cellulosome - Abstract
the Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS) grant LA/P/0059/2020. LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy - i4HB. National Institutes of Health R01-GM129325 and the Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases. Publisher Copyright: © 2022 The Author(s) The cellulosome is an elaborate multi-enzyme structure secreted by many anaerobic microorganisms for the efficient degradation of lignocellulosic substrates. It is composed of multiple catalytic and non-catalytic components that are assembled through high-affinity protein-protein interactions between the enzyme-borne dockerin (Doc) modules and the repeated cohesin (Coh) modules present in primary scaffoldins. In some cellulosomes, primary scaffoldins can interact with adaptor and cell-anchoring scaffoldins to create structures of increasing complexity. The cellulosomal system of the ruminal bacterium, Ruminococcus flavefaciens, is one of the most intricate described to date. An unprecedent number of different Doc specificities results in an elaborate architecture, assembled exclusively through single-binding-mode type-III Coh-Doc interactions. However, a set of type-III Docs exhibits certain features associated with the classic dual-binding mode Coh-Doc interaction. Here, the structure of the adaptor scaffoldin-borne ScaH Doc in complex with the Coh from anchoring scaffoldin ScaE is described. This complex, unlike previously described type-III interactions in R. flavefaciens, was found to interact in a dual-binding mode. The key residues determining Coh recognition were also identified. This information was used to perform structure-informed protein engineering to change the electrostatic profile of the binding surface and to improve the affinity between the two modules. The results show that the nature of the residues in the ligand-binding surface plays a major role in Coh recognition and that Coh-Doc affinity can be manipulated through rational design, a key feature for the creation of designer cellulosomes or other affinity-based technologies using tailored Coh-Doc interactions. publishersversion published
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- 2022
24. Magnetic particles used in a new approach for designed protein crystallization
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Ana Luísa Carvalho, Raquel Santos, Maria João Romão, Ana C. A. Roque, DQ - Departamento de Química, and UCIBIO - Applied Molecular Biosciences Unit
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Chemistry(all) ,Protein Data Bank (RCSB PDB) ,Crystal growth ,General Chemistry ,Protein engineering ,Condensed Matter Physics ,Benzamidine ,law.invention ,chemistry.chemical_compound ,Protein structure ,Materials Science(all) ,chemistry ,Chemical engineering ,law ,General Materials Science ,Target protein ,Crystallization ,skin and connective tissue diseases ,Protein crystallization - Abstract
PD/BD/105753/2014 PTDC/BII-BIO/28878/2017 UIDB/04378/ 2020 POCI-01-0145-FEDER-007728 After more than one hundred and thirty thousand protein structures determined by X-ray crystallography, the challenge of protein crystallization for 3D structure determination remains. In the quest for additives for efficient protein crystallization, inorganic materials emerge as an alternative. Magnetic particles (MPs) are versatile inorganic materials, easy to use, modify and manipulate in a wide range of biological assays. The potential of using functionalised MPs as crystallization chaperones for protein crystallization was shown in this work. MPs with distinct coatings were rationally designed to promote protein crystallization by affinity-triggered heterogeneous nucleation. Hen egg white lysozyme (HEWL) and trypsin, were crystallized in the presence of MPs either bare or coated with a polysaccharide (chitin) or a protein (casein), respectively. The addition of MPs was characterized in terms of bound protein to the MPs, crystal morphology, time-lapse of crystal emergence, crystallization yield fold change and crystal diffraction quality for structure determination. The MPs additives have shown to bind to the respective target protein, and to promote nucleation and crystal growth without compromising crystal morphology. On the other hand, MPs addition led to faster detectable crystal emergence and up to 13 times higher crystallization yield, addressing some the challenges in protein crystallization, the main bottleneck of macromolecular crystallography. Structure determination of the protein crystallized in the presence of MPs revealed that the structural characteristics of the protein remained unchanged, as shown by the superposition with PDB annotated proteins. Moreover, and unlike most reported cases, it was possible to exclude the inhibitor benzamidine during trypsin crystallisation, which is a remarkable result opening new prospects in enzyme engineering and drug design. Our results show that MPs coated with affinity ligands to target proteins can be used as controlled and tailor-made crystallization inducers. authorsversion published
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- 2021
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25. Synthesis, Crystal Structure, and DFT Study of Two New Dinuclear Copper(I) Complexes Bearing Ar‐BIAN Ligands Functionalized with NO 2 Groups
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Teresa Avilés, César A. T. Laia, Maria José Calhorda, Sónia Barroso, Mani Outis, Ana Luísa Carvalho, João C. Lima, and Vitor Rosa
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Inorganic Chemistry ,Crystallography ,Bearing (mechanical) ,chemistry ,law ,chemistry.chemical_element ,Crystal structure ,Copper ,law.invention - Published
- 2020
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26. Tackling Humidity with Designer Ionic Liquid-Based Gas Sensing Soft Materials
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Carina Esteves, Susana I. C. J. Palma, Henrique M. A. Costa, Cláudia Alves, Gonçalo M. C. Santos, Efthymia Ramou, Ana Luísa Carvalho, Vitor Alves, Ana C. A. Roque, UCIBIO - Applied Molecular Biosciences Unit, DQ - Departamento de Química, and DCV - Departamento de Ciências da Vida
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Materials Science(all) ,Mechanics of Materials ,Mechanical Engineering ,humidity ,General Materials Science ,sensing mechanisms - Abstract
No. SCENT‐ERC‐2014‐STG‐639123, 2015–2022) UIDP/04378/2020 UIDB/04378/2020 LA/P/0140/2020 SFRH/BD/113112/2015 Relative humidity is simultaneously a sensing target and a contaminant in gas and volatile organic compound (VOC) sensing systems, where strategies to control humidity interference are required. An unmet challenge is the creation of gas-sensitive materials where the response to humidity is controlled by the material itself. Here, humidity effects are controlled through the design of gelatin formulations in ionic liquids without and with liquid crystals as electrical and optical sensors, respectively. In this design, the anions [DCA]− and [Cl]− of room temperature ionic liquids from the 1-butyl-3-methylimidazolium family tailor the response to humidity and, subsequently, sensing of VOCs in dry and humid conditions. Due to the combined effect of the materials formulations and sensing mechanisms, changing the anion from [DCA]− to the much more hygroscopic [Cl]−, leads to stronger electrical responses and much weaker optical responses to humidity. Thus, either humidity sensors or humidity-tolerant VOC sensors that do not require sample preconditioning or signal processing to correct humidity impact are obtained. With the wide spread of 3D- and 4D-printing and intelligent devices, the monitoring and tuning of humidity in sustainable biobased materials offers excellent opportunities in e-nose sensing arrays and wearable devices compatible with operation at room conditions. publishersversion published
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- 2022
27. Narrativas Visuais para Educação e Aprendizagem: estudo de prospecção científica e tecnológica
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Soletti, Ana Luísa Carvalho, Carvalho, Sandra Helena Vieira de, and Uchôa, Sílvia Beatriz Beger
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Aprendizagem ,Narrativa Visual ,Visual Narrative ,Educação ,Learning ,Education - Abstract
This work presents a bibliographic and patent review regarding the use of visual narrative applied to teaching and learning. The research is qualitative and quantitative, aiming to obtain in-depth and comprehensive results. Scopus and Web of Science platforms were used for the bibliographic research. For the patent review, the search was carried out on the Orbit®, Esp@cenet and INPI databases. The research showed that the visual narrative approach, applied to education, has been gaining ground in the academic field, with several studies that cover its understanding as an innovative tool, adopting different media and technologies. This approach facilitates the understanding and accessibility of various subjects, in different areas of knowledge, and can be applied to different audiences, being also a possible channel for the inclusion of individuals with different types of limitations. Este trabalho apresenta uma revisão bibliográfica e patentária referente ao uso da narrativa visual aplicada ao ensino e à aprendizagem. A pesquisa tem caráter qualitativo e quantitativo, de forma a se obter resultados aprofundados e abrangentes. Foram utilizadas as plataformas Scopus e Web of Science para o levantamento bibliográfico. Para o levantamento patentário, a busca foi realizada nas bases Orbit®, Esp@cenet e INPI. A pesquisa mostrou que a abordagem da narrativa visual aplicada à educação vem ganhando espaço na área acadêmica, com diversos estudos que abrangem seu entendimento como ferramenta inovadora, adotando diferentes mídias e tecnologias. Essa abordagem facilita a compreensão e acessibilidade de diversos assuntos, em diferentes áreas do conhecimento, podendo ser aplicada a diferentes públicos, sendo também um possível canal de inclusão de indivíduos com diferentes tipos de limitações.
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- 2022
28. Mutational Spectrum, Ocular and Olfactory Phenotypes of CNGB1-Related RP-Olfactory Dysfunction Syndrome in a Multiethnic Cohort
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Sara Geada, Francisco Teixeira-Marques, Bruno Teixeira, Ana Luísa Carvalho, Nuno Lousan, Jorge Saraiva, Joaquim Murta, Rufino Silva, Xavier Zanlonghi, Sabine Defoort-Dhellemmes, Vasily Smirnov, Claire-Marie Dhaenens, Catherine Blanchet, Isabelle Meunier, and João Pedro Marques
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inherited retinal disease ,rod-cone degeneration ,retinitis pigmentosa ,olfactory dysfunction ,CNGB1 ,Genetics ,Genetics (clinical) - Abstract
CNGB1 gene mutations are a well-known cause of autosomal recessive retinitis pigmentosa (RP), which was recently associated with olfactory dysfunction. The purpose of this study was to report the molecular spectrum and the ocular and olfactory phenotypes of a multiethnic cohort with CNGB1-associated RP. A cross-sectional case series was conducted at two ophthalmic genetics referral centers. Consecutive patients with molecularly confirmed CNGB1-related RP were included. All patients underwent a complete ophthalmological examination complemented by psychophysical olfactory evaluation. Fifteen patients (10 families: 8 Portuguese, 1 French, and 1 Turkish), mean aged 57.13 ± 15.37 years old (yo), were enrolled. Seven disease-causing variants were identified, two of which are reported for the first time: c.2565_2566del and c.2285G > T. Although 11/15 patients reported onset of nyctalopia before age 10, diagnosis was only established after 30 yo in 9/15. Despite widespread retinal degeneration being present in 14/15 probands, a relatively preserved visual acuity was observed throughout follow-up. Olfactory function was preserved in only 4/15 patients, all of whom carried at least one missense variant. Our study supports previous reports of an autosomal recessive RP-olfactory dysfunction syndrome in association with certain disease-causing variants in the CNGB1 gene and expands the mutational spectrum of CNGB1-related disease by reporting two novel variants.
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- 2023
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29. The SOUL family of heme-binding proteins: Structure and function 15 years later
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Jean-Marc Moulis, Susana S. Aveiro, Anjos L. Macedo, Gloria C. Ferreira, Ana Luísa Carvalho, Alastair G. McEwen, Leonildo Delgado, Brian J. Goodfellow, João E. Rodrigues, Filipe Freire, Peggy Charbonnier, Catherine Birck, Pierre Poussin-Courmontagne, CICECO, Departamento de Química, Instituto de Biologia Experimental e Tecnológica (IBET), Instituto de Tecnologia Química e Biológica António Xavier (ITQB), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA), Unidade de Ciencias Biomoleculares Aplicadas (UCIBIO), Requimte, Departamento de Química (DQ), Faculdade de Ciências e Tecnologia = School of Science & Technology (FCT NOVA), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Faculdade de Ciências e Tecnologia = School of Science & Technology (FCT NOVA), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade do Porto-Departamento de Química (DQ), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade do Porto, GreenCoLab - Associação Oceano Verde, Universidade do Algarve, Métaux et Organes (MET&OR), Laboratoire de Chimie et Biologie des Métaux (LCBM - UMR 5249), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Laboratory of Fundamental and Applied Bioenergetics = Laboratoire de bioénergétique fondamentale et appliquée (LBFA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Grenoble Alpes (UGA), Equity Analyst Biotech & Healthcare, Morsani College of Medicine [Tampa, USA], University of South Florida [Tampa] (USF), Center for Neuroscience and Cell Biology (CNC) (CNC), University of Coimbra [Portugal] (UC)-Neuroscience Research Domain, Centre for Integrative Biology - CBI (Inserm U964 - CNRS UMR7104 - IGBMC), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Universidade do Porto = University of Porto-Departamento de Química (DQ), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade do Porto = University of Porto-Departamento de Química (DQ), and Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)
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Heme binding ,Globular protein ,Protein Data Bank (RCSB PDB) ,Inorganic Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Protein structure ,NMR spectroscopy ,Materials Chemistry ,HEBP1 ,[CHIM.COOR]Chemical Sciences/Coordination chemistry ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Physical and Theoretical Chemistry ,HEBP2 ,Function ,Heme ,Histidine ,030304 developmental biology ,X-ray crystallography ,chemistry.chemical_classification ,0303 health sciences ,Tetrapyrrole binding ,Structure ,chemistry ,SOUL protein ,030220 oncology & carcinogenesis ,Biophysics ,Heteronuclear single quantum coherence spectroscopy - Abstract
International audience; The SOUL, or heme-binding protein HBP/SOUL, family represents a group of evolutionary conservedputative heme-binding proteins that contains a number of members in animal, plant and bacterial spe-cies. The structures of the murine form of HEBP1, or p22HBP, and the human form of HEBP2, or SOUL,have been determined in 2006 and 2011 respectively.In this work we discuss the structures of HEBP1 and HEBP2 in light of new X-ray data for heme boundmurine HEBP1. The interaction between tetrapyrroles and HEBP1, initially proven to be hydrophobic innature, was thought to also involve electrostatic interactions between heme propionate groups and pos-itively charged amino acid side chains. However, the new X-ray structure, and results from murine HEBP1variants and human HEBP1, confirm the hydrophobic nature of the heme-HEBP1 interaction, resulting inKdvalues in the low nanomolar range, and rules out any electrostatic stabilization. Results from NMRrelaxation time measurements for human HEBP1 describe a rigid globular protein with no change inmotional regime upon heme binding.X-ray structures deposited in the PDB for human HEBP2 are very similar to each other and to the newheme-bound murine HEBP1 X-ray structure (backbone rmsd ca. 1 Å). Results from a HSQC spectrum cen-tred on the histidine side chain Nd-proton region for HEBP2 confirm that HEBP2 does not bind heme viaH42 as no chemical shift differences were observed upon heme addition for backbone NH and Ndprotons.A survey of the functions attributed to HEBP1 and HEBP2 over the last 20 years span a wide range ofcellular pathways. Interestingly, many of them are specific to higher eukaryotes, particularly mammalsand a potential link between heme release under oxidative stress and human HEBP1 is also examinedusing recent data. However, at the present moment, trying to relate function to the involvement of hemehttps://doi.org/10.1016/j.ccr.2021.2141890010-8545/Ó2021 Elsevier B.V. All rights reserved.Abbreviations:HEBP1, Heme-binding protein 1 (or p22HBP); HEBP2, Heme-binding protein 2 (or SOUL); BH3, Bcl-2 homology 3; HSQC, heteronuclear single quantumcoherence spectroscopy; TROSY, transverse relaxation optimized spectroscopy; FQ, fluorescence quenching; PPIX, protoporphyrin IX; sGC, solubleGuanylyl Cyclase; hetNOE,heteronuclear nuclear Overhauser effect; rmsd, root mean squared deviation; BMRB, biological magnetic resonance bank; VAST, vector alignment search tool; MEL, murineerythroleukemia.⇑Corresponding authors.E-mail addresses:brian.goodfellow@ua.pt(B.J. Goodfellow),mdam@fct.unl(A.L. Macedo).Coordination Chemistry Reviews 448 (2021) 214189Contents lists available atScienceDirectCoordination Chemistry Reviewsjournal homepage: www.elsevier.com/locate/ccr
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- 2021
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30. Mapping Molecular Recognition of β1,3-1,4-Glucans by a Surface Glycan-Binding Protein from the Human Gut Symbiont Bacteroides ovatus
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Cláudia Nunes, Manuel A. Coimbra, Joana L. A. Brás, Filipa Trovão, Carlos M. G. A. Fontes, Lisete M. Silva, Ten Feizi, Benedita A Pinheiro, Barbara Mulloy, Wengang Chai, Angelina Sá Palma, Yan Liu, Viviana G Correia, Ana Luísa Carvalho, UCIBIO - Applied Molecular Biosciences Unit, and DQ - Departamento de Química
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Microbiology (medical) ,Glycan ,Physiology ,Oligosaccharides ,β-glucan ,010402 general chemistry ,01 natural sciences ,Bacteroides ovatus ,Microbiology ,03 medical and health sciences ,Molecular recognition ,Bacterial Proteins ,SDG 3 - Good Health and Well-being ,SusD-like proteins ,Dietary Carbohydrates ,Genetics ,Bacteroides ,Humans ,Protein–carbohydrate interactions ,Microbiome ,Binding site ,Glucans ,Binding selectivity ,030304 developmental biology ,X-ray crystallography ,2. Zero hunger ,0303 health sciences ,Binding Sites ,General Immunology and Microbiology ,Ecology ,biology ,Chemistry ,Binding protein ,Membrane Proteins ,polysaccharide utilization loci ,Cell Biology ,Periplasmic space ,QR1-502 ,Gastrointestinal Microbiome ,0104 chemical sciences ,Bacteroides ovatu ,Infectious Diseases ,Biochemistry ,Periplasm ,protein-carbohydrate interactions ,biology.protein ,Carrier Proteins ,Research Article ,carbohydrate microarrays - Abstract
contract DL-57/2016 WT108430/Z/15/Z WT218304/Z/19/Z 22-FY18-821 A multigene polysaccharide utilization locus (PUL) encoding enzymes and surface carbohydrate (glycan)-binding proteins (SGBPs) was recently identified in prominent members of Bacteroidetes in the human gut and characterized in Bacteroides ovatus. This PUL-encoded system specifically targets mixed-linkage β1,3-1,4-glucans, a group of diet-derived carbohydrates that promote a healthy microbiota and have potential as prebiotics. The BoSGBPMLG-A protein encoded by the BACOVA_2743 gene is a SusD-like protein that plays a key role in the PUL's specificity and functionality. Here, we perform a detailed analysis of the molecular determinants underlying carbohydrate binding by BoSGBPMLG-A, combining carbohydrate microarray technology with quantitative affinity studies and a high-resolution X-ray crystallography structure of the complex of BoSGBPMLG-A with a β1,3-1,4-nonasaccharide. We demonstrate its unique binding specificity toward β1,3-1,4-gluco-oligosaccharides, with increasing binding affinities up to the octasaccharide and dependency on the number and position of β1,3 linkages. The interaction is defined by a 41-Å-long extended binding site that accommodates the oligosaccharide in a mode distinct from that of previously described bacterial β1,3-1,4-glucan-binding proteins. In addition to the shape complementarity mediated by CH-π interactions, a complex hydrogen bonding network complemented by a high number of key ordered water molecules establishes additional specific interactions with the oligosaccharide. These support the twisted conformation of the β-glucan backbone imposed by the β1,3 linkages and explain the dependency on the oligosaccharide chain length. We propose that the specificity of the PUL conferred by BoSGBPMLG-A to import long β1,3-1,4-glucan oligosaccharides to the bacterial periplasm allows Bacteroidetes to outcompete bacteria that lack this PUL for utilization of β1,3-1,4-glucans. IMPORTANCE With the knowledge of bacterial gene systems encoding proteins that target dietary carbohydrates as a source of nutrients and their importance for human health, major efforts are being made to understand carbohydrate recognition by various commensal bacteria. Here, we describe an integrative strategy that combines carbohydrate microarray technology with structural studies to further elucidate the molecular determinants of carbohydrate recognition by BoSGBPMLG-A, a key protein expressed at the surface of Bacteroides ovatus for utilization of mixed-linkage β1,3-1,4-glucans. We have mapped at high resolution interactions that occur at the binding site of BoSGBPMLG-A and provide evidence for the role of key water-mediated interactions for fine specificity and affinity. Understanding at the molecular level how commensal bacteria, such as prominent members of Bacteroidetes, can differentially utilize dietary carbohydrates with potential prebiotic activities will shed light on possible ways to modulate the microbiome to promote human health. publishersversion published
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- 2021
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31. Molecular basis for the preferential recognition of β1,3‐1,4‐glucans by the family 11 carbohydrate‐binding module from Clostridium thermocellum
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Angelina S. Palma, Ana Luísa Carvalho, João Medeiros-Silva, Eurico J. Cabrita, Wengang Chai, Pedro Bule, Filipa Marcelo, Aldino Viegas, Diana Ribeiro, Carlos M. G. A. Fontes, and Virgínia M. R. Pires
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Models, Molecular ,0301 basic medicine ,Protein Conformation ,Stacking ,Sequence Homology ,Crystallography, X-Ray ,Biochemistry ,Substrate Specificity ,Clostridium thermocellum ,Cellulosome ,03 medical and health sciences ,0302 clinical medicine ,Bacterial Proteins ,Tetrasaccharide ,Amino Acid Sequence ,Glucans ,Molecular Biology ,Glucan ,chemistry.chemical_classification ,Binding Sites ,biology ,Chemistry ,Cell Biology ,computer.file_format ,Ligand (biochemistry) ,Protein Data Bank ,biology.organism_classification ,030104 developmental biology ,030220 oncology & carcinogenesis ,Carbohydrate-binding module ,computer ,Protein Binding - Abstract
Understanding the specific molecular interactions between proteins and β1,3-1,4-mixed-linked d-glucans is fundamental to harvest the full biological and biotechnological potential of these carbohydrates and of proteins that specifically recognize them. The family 11 carbohydrate-binding module from Clostridium thermocellum (CtCBM11) is known for its binding preference for β1,3-1,4-mixed-linked over β1,4-linked glucans. Despite the growing industrial interest of this protein for the biotransformation of lignocellulosic biomass, the molecular determinants of its ligand specificity are not well defined. In this report, a combined approach of methodologies was used to unravel, at a molecular level, the ligand recognition of CtCBM11. The analysis of the interaction by carbohydrate microarrays and NMR and the crystal structures of CtCBM11 bound to β1,3-1,4-linked glucose oligosaccharides showed that both the chain length and the position of the β1,3-linkage are important for recognition, and identified the tetrasaccharide Glcβ1,4Glcβ1,4Glcβ1,3Glc sequence as a minimum epitope required for binding. The structural data, along with site-directed mutagenesis and ITC studies, demonstrated the specificity of CtCBM11 for the twisted conformation of β1,3-1,4-mixed-linked glucans. This is mediated by a conformation-selection mechanism of the ligand in the binding cleft through CH-π stacking and a hydrogen bonding network, which is dependent not only on ligand chain length, but also on the presence of a β1,3-linkage at the reducing end and at specific positions along the β1,4-linked glucan chain. The understanding of the detailed mechanism by which CtCBM11 can distinguish between linear and mixed-linked β-glucans strengthens its exploitation for the design of new biomolecules with improved capabilities and applications in health and agriculture. DATABASE: Structural data are available in the Protein Data Bank under the accession codes 6R3M and 6R31.
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- 2019
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32. Abnormal mGluR-mediated synaptic plasticity and autism-like behaviours in Gprasp2 mutant mice
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João Peça, Mário Jorge da Silva Carvalho, Xian Gao, Pedro A. Ferreira, Ana L. Cardoso, Gladys L. Caldeira, Mariana Laranjo, Joana R. Guedes, Guoping Feng, Ana Luísa Carvalho, Dongqing Wang, Mohamed Edfawy, Marta I Pereira, and Lara O. Franco
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0301 basic medicine ,Science ,Dendritic Spines ,Receptor, Metabotropic Glutamate 5 ,General Physics and Astronomy ,02 engineering and technology ,Neurotransmission ,Biology ,Hippocampus ,Synaptic Transmission ,General Biochemistry, Genetics and Molecular Biology ,Article ,03 medical and health sciences ,Glutamatergic ,Memory ,mental disorders ,medicine ,Animals ,Autistic Disorder ,Receptor ,lcsh:Science ,Mice, Knockout ,Multidisciplinary ,Neuronal Plasticity ,Behavior, Animal ,Metabotropic glutamate receptor 5 ,Intracellular Signaling Peptides and Proteins ,General Chemistry ,021001 nanoscience & nanotechnology ,medicine.disease ,Mice, Mutant Strains ,Mice, Inbred C57BL ,030104 developmental biology ,Autism spectrum disorder ,Metabotropic glutamate receptor ,Synaptic plasticity ,Autism ,lcsh:Q ,0210 nano-technology ,Neuroscience ,Gene Deletion - Abstract
Autism spectrum disorder (ASD) is characterized by dysfunction in social interactions, stereotypical behaviours and high co-morbidity with intellectual disability. A variety of syndromic and non-syndromic neurodevelopmental disorders have been connected to alterations in metabotropic glutamate receptor (mGluR) signalling. These receptors contribute to synaptic plasticity, spine maturation and circuit development. Here, we investigate the physiological role of Gprasp2, a gene linked to neurodevelopmental disabilities and involved in the postendocytic sorting of G-protein-coupled receptors. We show that Gprasp2 deletion leads to ASD-like behaviour in mice and alterations in synaptic communication. Manipulating the levels of Gprasp2 bidirectionally modulates the surface availability of mGluR5 and produces alterations in dendritic complexity, spine density and synaptic maturation. Loss of Gprasp2 leads to enhanced hippocampal long-term depression, consistent with facilitated mGluR-dependent activation. These findings demonstrate a role for Gprasp2 in glutamatergic synapses and suggest a possible mechanism by which this gene is linked to neurodevelopmental diseases., GPRASP2 plays a role in trafficking of GPCRs and mutations in this gene have been linked to neurodevelopmental disorders. Here the authors study the role of Gprasp2 in the CNS and show that it regulates the surface availability of mGluR5 receptors and that knockout mice for this protein show autistic-like behavioural abnormalities.
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- 2019
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33. Ligand-independent activity of the ghrelin receptor modulates AMPA receptor trafficking and supports memory formation
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José A. Esteban, Lyn Rosenbrier Ribeiro, Luísa Cortes, Luís Ribeiro, Bárbara Oliveiros, Mário Jorge da Silva Carvalho, Tatiana Catarino, Patricio Opazo, Sandra D. Santos, Daniel Choquet, Ana Luísa Carvalho, João Peça, Brain and Behavior Research Foundation, Fundação para a Ciência e a Tecnologia (Portugal), Interdisciplinary Institute for Neuroscience [Bordeaux] (IINS), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)
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0301 basic medicine ,[SDV]Life Sciences [q-bio] ,Long-Term Potentiation ,Hippocampus ,AMPA receptor ,Hippocampal formation ,Ligands ,Biochemistry ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Memory ,Animals ,Receptors, AMPA ,Receptors, Ghrelin ,Receptor ,Molecular Biology ,ComputingMilieux_MISCELLANEOUS ,Chemistry ,Long-term potentiation ,Cell Biology ,Ghrelin ,3. Good health ,030104 developmental biology ,Synaptic plasticity ,Excitatory postsynaptic potential ,Neuroscience ,030217 neurology & neurosurgery ,hormones, hormone substitutes, and hormone antagonists ,Signal Transduction - Abstract
The biological signals of hunger, satiety, and memory are interconnected. The role of the hormone ghrelin in regulating feeding and memory makes ghrelin receptors attractive targets for associated disorders. We investigated the effects of the high ligand-independent activity of the ghrelin receptor GHS-R1a on the physiology of excitatory synapses in the hippocampus. Blocking this activity produced a decrease in the synaptic content of AMPA receptors in hippocampal neurons and a reduction in GluA1 phosphorylation at Ser. Reducing the ligand-independent activity of GHS-R1a increased the surface diffusion of AMPA receptors and impaired AMPA receptor–dependent synaptic delivery induced by chemical long-term potentiation. Accordingly, we found that blocking this GHS-R1a activity impaired spatial and recognition memory in mice. These observations support a role for the ligand-independent activity of GHS-R1a in regulating AMPA receptor trafficking under basal conditions and in the context of synaptic plasticity that underlies learning., NARSAD Independent Investigator Grant from the Brain and Behavior Research Foundation, by national funds through the Portuguese Science and Technology Foundation (FCT; POCI-01-0145-FEDER-007440, POCI-01-0145-FEDER-PTDC/SAUNMC/4888/2014, POCI-01-0145-FEDER-28541, POCI-01-0145-FEDER-022122, and UIDB/04539/2020), and by the European Regional Development Fund (ERDF), through the Centro 2020 Regional Operational Programme under project CENTRO-01-0145-FEDER-000008:BrainHealth 2020
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- 2021
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34. Design, Development and Deployment of a Web-Based Interoperable Registry for Inherited Retinal Dystrophies in Portugal – the IRD-PT
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José Fernando Castanha Henriques, João Pedro Marques, Joaquim Murta, Jorge M. Saraiva, Rufino Silva, and Ana Luísa Carvalho
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0301 basic medicine ,Registry ,Knowledge management ,Computer science ,Epidemiology ,Data management ,Interoperability ,Natural history ,lcsh:Medicine ,Ontology (information science) ,03 medical and health sciences ,0302 clinical medicine ,Human Phenotype Ontology ,Retinal Dystrophies ,parasitic diseases ,Web application ,International Statistical Classification of Diseases and Related Health Problems ,Humans ,Pharmacology (medical) ,Clinical genetics ,Registries ,Genetics (clinical) ,Ecosystem ,Internet ,Portugal ,business.industry ,Research ,Inherited retinal dystrophies ,lcsh:R ,ICD-10 ,General Medicine ,Rare diseases ,030104 developmental biology ,Software deployment ,030221 ophthalmology & optometry ,business ,Software - Abstract
Background The development of multicenter patient registries promotes the generation of scientific knowledge by using real-world data. A country-wide, web-based registry for inherited retinal dystrophies (IRDs) empowers patients and community organizations, while supporting formal partnerships research. We aim to describe the design, development and deployment of a country-wide, with investigators and stakeholders in the global aim to develop high-value, high-utility web-based, user-friendly and interoperable registry for IRDs—the IRD-PT. Results The IRD-PT is a clinical/genetic research registry included in the retina.pt platform (https://www.retina.com.pt), which was developed by the Portuguese Retina Study Group. The retina.pt platform collects data on individuals diagnosed with retinal diseases, from several sites across Portugal, with over 1800 participants and over 30,000 consultations to date. The IRD-PT module interacts with the retina.pt core system which provides a range of basic functions for patient data management, while the IRD-PT module allows data capture for the specific purpose of IRDs. All IRDs are coded accordingly to the International Statistical Classification of Diseases and Related Health Problems (ICD) 9, ICD 10, ICD 11, and Orphanet Rare Disease Ontology (ORPHA codes) to make the IRD-PT interoperable with other IRD registries across the world. Furthermore, the genes are coded according to the Ontology of Genes and Genomes and Online Mendelian Inheritance in Man, whereas signs and symptoms are coded according to the Human Phenotype Ontology. The IRD-PT module pre-launched at Centro Hospitalar e Universitário de Coimbra, the largest reference center for IRDs in Portugal. As of April 1st 2020, finalized data from 537 participants were available for this preliminary analysis. Conclusions In the specific field of rare diseases, the use of registries increases research accessibility for individuals, while providing clinicians/investigators with a coherent data ecosystem necessary to boost research. Appropriate design and implementation of patient registries enables rapid decision making and ongoing data mining, ultimately leading to improved patient outcomes. We have described here the principles behind the design, development and deployment of a web-based, user-friendly and interoperable software tool aimed to generate important knowledge and collecting high-quality data on the epidemiology, genomic landscape and natural history of IRDs in Portugal.
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- 2020
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35. Constitutive ghrelin receptor activity modulates AMPA receptor traffic and supports memory formation
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Ana Luísa Carvalho, Sandra D. Santos, José A. Esteban, Luísa Cortes, Lyn Rosenbrier Ribeiro, Daniel Choquet, João Peça, Tatiana Catarino, Patricio Opazo, Luís Ribeiro, and Mário Jorge da Silva Carvalho
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Chemistry ,digestive, oral, and skin physiology ,Synaptic plasticity ,Excitatory postsynaptic potential ,Phosphorylation ,Long-term potentiation ,Ghrelin ,AMPA receptor ,Hippocampal formation ,Receptor ,hormones, hormone substitutes, and hormone antagonists ,Cell biology - Abstract
The ability of animals to store and retrieve food caches in the wild requires the integration of biological signals of hunger, satiety and memory. The role of ghrelin in regulating feeding and memory makes ghrelin receptors an important target to shape the required cellular and molecular responses. We investigated the effects of the high ligand-independent activity of the ghrelin receptor on the physiology of excitatory synapses. Blocking this type of activity produced a decrease in the synaptic content of AMPA receptors in hippocampal neurons and a reduction in GluA1 phosphorylation at Ser845. Impaired constitutive activity from the ghrelin receptor increased surface diffusion of AMPA receptors and impaired AMPA receptor synaptic delivery mediated by chemical long-term potentiation. These observations support a role for the constitutive activity of the ghrelin receptor in regulating AMPA receptor trafficking under basal conditions and synaptic plasticity. Accordingly, we found that blocking the ghrelin receptor constitutive activity impairs spatial and recognition memory.Impact statementThis work uncovers a role for the constitutive activity of the ghrelin receptor in memory, and in the regulation of the synaptic levels of AMPA receptors, their mobility and synaptic plasticity. Underscoring the importance of deciphering the physiological role of constitutive ghrelin receptor activity, ghrelin receptor inverse agonism is now being considered as a therapy to treat alcohol use disorder.
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- 2020
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36. Em que medida a humanização do processo penal poderia influenciar o combate à violência doméstica
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Santos, Ana Luísa Carvalho de Oliveira
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Papel da mulher na sociedade ,Humanização ,Boas práticas ,Sistema de Justiça Criminal ,Lei Maria da Penha - Abstract
Submitted by denison pereira (denison.rolim@uniceub.br) on 2021-01-19T14:06:54Z No. of bitstreams: 1 Ana Santos 21600205 (2).pdf: 273701 bytes, checksum: d468e66d07d7133dde660e35c45e8440 (MD5) Approved for entry into archive by Fernanda Weschenfelder (fernanda.weschenfelder@uniceub.br) on 2021-03-23T15:24:40Z (GMT) No. of bitstreams: 1 Ana Santos 21600205 (2).pdf: 273701 bytes, checksum: d468e66d07d7133dde660e35c45e8440 (MD5) Made available in DSpace on 2021-03-23T15:24:40Z (GMT). No. of bitstreams: 1 Ana Santos 21600205 (2).pdf: 273701 bytes, checksum: d468e66d07d7133dde660e35c45e8440 (MD5) Previous issue date: 2021-01-19 Este artigo tem como objetivo analisar qual seria o impacto da humanização por meio da inserção das boas práticas dispostas na Lei 11.340/2006 (Lei Maria da Penha) no processo penal. Trata-se de uma pesquisa teórica que teve como marco a Lei 11.340/2006, o livro Processo Penal Feminista da autora Soraia da Rosa Mendes que aborda de forma sensível a falta de preparação das redes de atendimento à mulher em situação de violência doméstica desde a delegacia até o juizado, bem como artigos digitais que fundamentaram o impacto do patriarcado na participação sociocultural da mulher e como isso reflete diretamente na violência de gênero. Conclui-se que a Lei Maria da Penha é completa em seus dispositivos, restando apenas a efetiva implementação das boas práticas para que a mulher vítima, de fato, se sinta acolhida em todos os momentos da busca por proteção do Sistema de Justiça Criminal, assim como antes e depois da violência.
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- 2020
37. It takes two to tango: Concerted protein translation and degradation necessary for synaptic scaling
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Ana Luísa Carvalho and Dominique Fernandes
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Synaptic scaling ,General Immunology and Microbiology ,QH301-705.5 ,General Neuroscience ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,microRNA ,Protein biosynthesis ,Premovement neuronal activity ,Gene silencing ,Biology (General) ,Protein translation ,General Agricultural and Biological Sciences ,Degradation (telecommunications) - Abstract
Synaptic scaling allows neurons to adjust synaptic strength in response to chronic alterations in neuronal activity. A new study in PLOS Biology identifies a pathway that synergizes protein synthesis and degradation with remodeling of the microRNA (miRNA)-induced silencing complex (miRISC) to mediate synaptic scaling.
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- 2021
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38. Stability and Ligand Promiscuity of Type A Carbohydrate-binding Modules Are Illustrated by the Structure of Spirochaeta thermophila StCBM64C
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Shabir Najmudin, Joana L. A. Brás, Carlos M. G. A. Fontes, Victor D. Alves, Ana Luísa Carvalho, Virgínia M. R. Pires, Immacolata Venditto, Pedro Bule, Duarte M. F. Prazeres, Vânia Cardoso, Maria João Romão, Márcia A. S. Correia, Luís M. A. Ferreira, and Pedro Miguel Matos Pereira
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Models, Molecular ,0301 basic medicine ,Protein Conformation ,Cellulase ,Biology ,Crystallography, X-Ray ,Polysaccharide ,Biochemistry ,Cell wall ,03 medical and health sciences ,chemistry.chemical_compound ,Bacterial Proteins ,Chitin ,Cell Wall ,Cellulases ,Asparagine ,Cellulose ,Glucans ,Molecular Biology ,chemistry.chemical_classification ,Binding Sites ,030102 biochemistry & molecular biology ,Osmolar Concentration ,Temperature ,Spirochaeta ,Cell Biology ,Ligand (biochemistry) ,Xyloglucan ,030104 developmental biology ,chemistry ,Protein Structure and Folding ,biology.protein ,Carbohydrate Metabolism ,Xylans ,Protein Binding - Abstract
Deconstruction of cellulose, the most abundant plant cell wall polysaccharide, requires the cooperative activity of a large repertoire of microbial enzymes. Modular cellulases contain non-catalytic type A carbohydrate-binding modules (CBMs) that specifically bind to the crystalline regions of cellulose, thus promoting enzyme efficacy through proximity and targeting effects. Although type A CBMs play a critical role in cellulose recycling, their mechanism of action remains poorly understood. Here we produced a library of recombinant CBMs representative of the known diversity of type A modules. The binding properties of 40 CBMs, in fusion with an N-terminal GFP domain, revealed that type A CBMs possess the ability to recognize different crystalline forms of cellulose and chitin over a wide range of temperatures, pH levels, and ionic strengths. A Spirochaeta thermophila CBM64, in particular, displayed plasticity in its capacity to bind both crystalline and soluble carbohydrates under a wide range of extreme conditions. The structure of S. thermophila StCBM64C revealed an untwisted, flat, carbohydrate-binding interface comprising the side chains of four tryptophan residues in a co-planar linear arrangement. Significantly, two highly conserved asparagine side chains, each one located between two tryptophan residues, are critical to insoluble and soluble glucan recognition but not to bind xyloglucan. Thus, CBM64 compact structure and its extended and versatile ligand interacting platform illustrate how type A CBMs target their appended plant cell wall-degrading enzymes to a diversity of recalcitrant carbohydrates under a wide range of environmental conditions.
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- 2017
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39. Regulation of neuronal mRNA splicing and Tau isoform ratio by ATXN3 through deubiquitylation of splicing factors
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Andreia Neves-Carvalho, Sara Duarte-Silva, Joana M. Silva, Liliana Meireles-Costa, Daniela Monteiro-Fernandes, Joana S. Correia, Beatriz Rodrigues, Sasja Heetveld, Bruno Almeida, Natalia Savytska, Jorge Diogo Da Silva, Andreia Teixeira-Castro, Ioannis Sotiropoulos, Ana Luísa Carvalho, Peter Heutink, Ka Wan Li, and Patrícia Maciel
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chemistry.chemical_classification ,Gene isoform ,0303 health sciences ,Mechanism (biology) ,Regulator ,Biology ,Cell biology ,Transcriptome ,03 medical and health sciences ,Exon ,0302 clinical medicine ,Enzyme ,Ubiquitin ,chemistry ,RNA splicing ,biology.protein ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
The ubiquitylation/deubiquitylation balance in cells is maintained by deubiquitylating enzymes, including ATXN3. The precise role of this protein, mutated in spinocerebellar ataxia type 3 (SCA3), remains elusive, as few substrates for its deubiquitylating activity were identified. Here, we characterized the ubiquitome of neuronal cells lacking ATXN3, and found altered polyubiquitylation in a large proportion of proteins involved in RNA metabolism, including splicing factors. Using transcriptomic analysis and reporter minigenes we confirmed that splicing was globally altered in these cells. Among the candidate targets of ATXN3 was SRSF7 (9G8), a key regulator of MAPT (Tau) exon 10 splicing. Loss-of-function of ATXN3 led to reduced SRSF7 levels and a deregulation of MAPT exon 10 splicing, resulting in a decreased 4R/3R-Tau ratio. Similar alterations were found in cellular models of expanded polyQ ATXN3 and SCA3 patient brains, pointing to a relevant role of this mechanism in SCA3, and establishing a previously unsuspected link between two key proteins involved in different neurodegenerative disorders.
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- 2019
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40. SLMP53-1 interacts with wild-type and mutant p53 DNA-binding domain and reactivates multiple hotspot mutations
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Carla Cristina Marques de Oliveira, Joana Soares, Maria João Romão, Sara Gomes, Filipa Marcelo, Margarida Bastos, Valentina Barcherini, Lucília Domingues, Helena Ramos, Daniel F. A. R. Dourado, Gilberto Fronza, A. Gomes, Maria M. M. Santos, Benedita A. Pinheiro, Ana Luísa Carvalho, Paola Monti, Lucília Saraiva, Alexandra T. P. Carvalho, Joana B. Loureiro, and Universidade do Minho
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0301 basic medicine ,p53 ,Thermal shift assay ,In silico ,Mutant ,Biophysics ,Apoptosis ,Isoindoles ,Biochemistry ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Biotecnologia Médica [Ciências Médicas] ,Protein Domains ,law ,Cell Line, Tumor ,Neoplasms ,Chemotherapy ,Humans ,Molecular Biology ,Oxazoles ,Cancer ,Cell Proliferation ,Science & Technology ,Reactivator ,Wild type ,DNA-binding domain ,In vitro ,3. Good health ,Cell biology ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Mutation ,Suppressor ,Ciências Médicas::Biotecnologia Médica ,Tumor Suppressor Protein p53 ,DNA - Abstract
Background Half of human cancers harbour TP53 mutations that render p53 inactive as a tumor suppressor. As such, reactivation of mutant (mut)p53 through restoration of wild-type (wt)-like function represents one of the most promising therapeutic strategies in cancer treatment. Recently, we have reported the (S)-tryptophanol-derived oxazoloisoindolinone SLMP53-1 as a new reactivator of wt and mutp53 R280K with in vitro and in vivo p53-dependent antitumor activity. The present work aimed a mechanistic elucidation of mutp53 reactivation by SLMP53-1. Methods and results By cellular thermal shift assay (CETSA), it is shown that SLMP53-1 induces wt and mutp53 R280K thermal stabilization, which is indicative of intermolecular interactions with these proteins. Accordingly, in silico studies of wt and mutp53 R280K DNA-binding domain with SLMP53-1 unveiled that the compound binds at the interface of the p53 homodimer with the DNA minor groove. Additionally, using yeast and p53-null tumor cells ectopically expressing distinct highly prevalent mutp53, the ability of SLMP53-1 to reactivate multiple mutp53 is evidenced. Conclusions SLMP53-1 is a p53-activating agent with the ability to directly target wt and a set of hotspot mutp53. General Significance This work reinforces the encouraging application of SLMP53-1 in the personalized treatment of cancer patients harboring distinct p53 status., European Union (FEDER funds through Programa Operacional Factores de Competitividade – COMPETE) and National Funds (FCT/MEC, Fundação para a Ciência e Tecnologia and Ministério da Educação e Ciência) through the projects UID/QUI/50006/2019, COMPETE 2020 (POCI-01-0145-FEDER-006684/POCI-01-0145-FEDER-007440) and the BioTecNorte operation (NORTE-01-0145-FEDER-000004), (3599-PPCDT) PTDC/DTP-FTO/1981/2014 – POCI-01-0145-FEDER-016581 and UID/QUI/0081/2013; the Italian Association for Cancer Research, AIRC (IG#5506 to G.F.), Compagnia S. Paolo, Turin, Italy (Project 2017.0526 to G.F.) and Ministry of Health, (Project 5 × 1000, 2013 and 2015; Current research 2016). We also thank FCT for the financial support through CEECIND/01772/2017 (M.M.M. Santos), PTDC/QUI-QOR/29664/2017, UID/DTP/04138/2013, IF/01272/2015 (A. Carvalho), IF/00780/2015 (F. Marcelo) and fellowships SFRH/BD/119144/2016 (H. Ramos), PD/BD/114046/2015 (A. S. Gomes), SFRH/BD/128673/2017 (J. B. Loureiro), SFRH/BD/96189/2013 (S. Gomes), SFRH/BPD/110640/2015 (C. Oliveira) and PD/BI/135334/2017 (V. Barcherini), and the Programa Operacional Potencial Humano (POCH), specifically the BiotechHealth Programme (PD/00016/2012), info:eu-repo/semantics/publishedVersion
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- 2019
41. N-Heterocyclic Olefin Catalysis for the Ring Opening of Cyclic Amidine Compounds: A Pathway to the Synthesis of ε-Caprolactam- and γ-Lactam-Derived Amines
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Sónia Barroso, Gabriela Malta, Paula S. Branco, Hugo Cruz, Luísa M. Ferreira, Daniela Peixoto, and Ana Luísa Carvalho
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Olefin fiber ,Bicyclic molecule ,010405 organic chemistry ,Organic Chemistry ,Imine ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Amidine ,Sodium borohydride ,chemistry.chemical_compound ,chemistry ,Nucleophile ,Lactam - Abstract
For the first time, 1,2-dimethyl-3-ethylimidazolium iodide (1a) catalyzes the ring opening of the bicyclic amidine system of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) or DBN (1,5-diazabicyclo[4.3.0]non-5-ene) on reaction with aldehydes. The mechanism here proposed involves an N-heterocyclic olefin (NHO) catalytic species that acts as a nucleophile to promote the cyclic amidine ring opening. The resulting e-caprolactam- and γ-lactam-derived imines were obtained in moderate to excellent yields (28-99%) and reduced to the corresponding amines by sodium borohydride. Confirmation of the imine product was achieved via single-crystal X-ray diffraction studies.
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- 2019
42. Disrupted AMPA Receptor Function upon Genetic- or Antibody-Mediated Loss of Autism-Associated CASPR2
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Jessica L. Whitt, Sandra D. Santos, Ana Luísa Carvalho, Ester Coutinho, Dominique Fernandes, Nuno Beltrão, Tiago Rondão, M. Isabel Leite, Hey Kyoung Lee, and Camilla Buckley
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Male ,Cognitive Neuroscience ,Nerve Tissue Proteins ,AMPA receptor ,Biology ,Autoantigens ,Synaptic Transmission ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Mice ,0302 clinical medicine ,medicine ,Animals ,Humans ,Receptors, AMPA ,Autistic Disorder ,Rats, Wistar ,Receptor ,Loss function ,030304 developmental biology ,Aged ,Autoantibodies ,Visual Cortex ,Mice, Knockout ,0303 health sciences ,Synaptic scaling ,Neuronal Plasticity ,Limbic encephalitis ,Membrane Proteins ,Original Articles ,medicine.disease ,Rats ,Synaptic plasticity ,Excitatory postsynaptic potential ,Developmental plasticity ,Encephalitis ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Neuropsychiatric disorders share susceptibility genes, suggesting a common origin. One such gene is CNTNAP2 encoding contactin-associated protein 2 (CASPR2), which harbours mutations associated to autism, schizophrenia, and intellectual disability. Antibodies targeting CASPR2 have also been recently described in patients with several neurological disorders, such as neuromyotonia, Morvan’s syndrome, and limbic encephalitis. Despite the clear implication of CNTNAP2 and CASPR2 in neuropsychiatric disorders, the pathogenic mechanisms associated with alterations in CASPR2 function are unknown. Here, we show that Caspr2 is expressed in excitatory synapses in the cortex, and that silencing its expression in vitro or in vivo decreases the synaptic expression of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors and the amplitude of AMPA receptor-mediated currents. Furthermore, Caspr2 loss of function blocks synaptic scaling in vitro and experience-dependent homoeostatic synaptic plasticity in the visual cortex. Patient CASPR2 antibodies decrease the dendritic levels of Caspr2 and synaptic AMPA receptor trafficking, and perturb excitatory transmission in the visual cortex. These results suggest that mutations in CNTNAP2 may contribute to alterations in AMPA receptor function and homoeostatic plasticity, and indicate that antibodies from anti-CASPR2 encephalitis patients affect cortical excitatory transmission.
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- 2019
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43. A dual cohesin–dockerin complex binding mode in Bacteroides cellulosolvens contributes to the size and complexity of its cellulosome
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Carlos M. G. A. Fontes, Pedro Bule, Victor D. Alves, Shabir Najmudin, Luís M. A. Ferreira, Ana Luísa Carvalho, Aldino Viegas, Marlene Duarte, Eurico J. Cabrita, José A. M. Prates, UCIBIO - Applied Molecular Biosciences Unit, and DQ - Departamento de Química
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0301 basic medicine ,Scaffold protein ,Cellobiose ,Chromosomal Proteins, Non-Histone ,cohesin ,Cell Cycle Proteins ,Dockerin ,ITC, Isothermal Titration Calorimetry ,Biochemistry ,Cellulosome ,Bacteroides cellulosolvens ,chemistry.chemical_compound ,B. cellulosolvens, Bacteroides (Pseudobacteroides) cellulosolvens ,rmsd, root-mean-square deviation ,Bacteroides ,C. thermocellum, Clostridium (Hungateiclostridium) thermocellum ,A. cellulolyticus, Acetivibrio (Hungateiclostridium) cellulolyticus ,Clostridiales ,cellulase ,biology ,R. flavefaciens, Ruminococcus flavefaciens ,Coh, Cohesin ,dual-binding ,Cell biology ,Cellulosomes ,C. cellulolyticum, Clostridium (Hungateiclostridium) cellulolyticum ,CAZymes, Carbohydrate Active enZymes ,dockerin ,Research Article ,crystal structure ,SLH, S-layer homology ,Cellulase ,Doc, Dockerin ,03 medical and health sciences ,Bacterial Proteins ,IMAC, Immobilized Metal-ion Affinity Chromatography ,Cellulose ,Molecular Biology ,030102 biochemistry & molecular biology ,Cohesin ,protein complex ,NGE, Nondenaturing Gel Electrophoresis ,Cell Biology ,030104 developmental biology ,chemistry ,cellulosome ,biology.protein - Abstract
The Cellulosome is an intricate macromolecular protein complex that centralizes the cellulolytic efforts of many anaerobic microorganisms through the promotion of enzyme synergy and protein stability. The assembly of numerous carbohydrate processing enzymes into a macromolecular multiprotein structure results from the interaction of enzyme-borne dockerin modules with repeated cohesin modules present in noncatalytic scaffold proteins, termed scaffoldins. Cohesin- dockerin (Coh-Doc) modules are typically classified into different types, depending on structural conformation and cellulosome role. Thus, type I Coh-Doc complexes are usually responsible for enzyme integration into the cellulosome, while type II Coh-Doc complexes tether the cellulosome to the bacterial wall. In contrast to other known cellulosomes, cohesin types from Bacteroides cellulosolvens, a cellulosome-producing bacterium capable of utilizing cellulose and cellobiose as carbon sources, are reversed for all scaffoldins, i.e., the type II cohesins are located on the enzyme-integrating primary scaffoldin, whereas the type I cohesins are located on the anchoring scaffoldins. It has been previously shown that type I B. cellulosolvens interactions possess a dual-binding mode that adds flexibility to scaffoldin assembly. Herein, we report the structural mechanism of enzyme recruitment into B. cellulosolvens cellulosome and the identification of the molecular determinants of its type II cohesin-dockerin interactions. The results indicate that, unlike other type II complexes, these possess a dual-binding mode of interaction, akin to type I complexes. Therefore, the plasticity of dualbinding mode interactions seems to play a pivotal role in the assembly of B. cellulosolvens cellulosome, which is consistent with its unmatched complexity and size. publishersversion published
- Published
- 2021
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44. Multiple domains in the C-terminus of NMDA receptor GluN2B subunit contribute to neuronal death following in vitro ischemia
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Kevin She, Carlos B. Duarte, Shinichiro Oku, Ann Marie Craig, Ana Luísa Carvalho, Miranda Mele, Marta Vieira, Jeannette Schmidt, Joana S. Ferreira, and Armanda E. Santos
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0301 basic medicine ,Programmed cell death ,Excitotoxicity ,Hippocampus ,Oxygen-glucose deprivation ,In Vitro Techniques ,medicine.disease_cause ,NMDA receptors ,Receptors, N-Methyl-D-Aspartate ,Clathrin ,Neuroprotection ,lcsh:RC321-571 ,Brain Ischemia ,Mice ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Animals ,Receptor ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,AP2 ,Cells, Cultured ,Cerebral Cortex ,Mice, Knockout ,Neurons ,Cell Death ,biology ,Glutamate receptor ,Cerebral ischemia ,Rats ,GluN2B ,Protein Subunits ,030104 developmental biology ,nervous system ,Neurology ,CaMKIIα ,biology.protein ,NMDA receptor ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Global cerebral ischemia induces selective degeneration of specific subsets of neurons throughout the brain, particularly in the hippocampus and cortex. One of the major hallmarks of cerebral ischemia is excitotoxicity, characterized by overactivation of glutamate receptors leading to intracellular Ca(2+) overload and ultimately neuronal demise. N-methyl-d-aspartate receptors (NMDARs) are considered to be largely responsible for excitotoxic injury due to their high Ca(2+) permeability. In the hippocampus and cortex, these receptors are most prominently composed of combinations of two GluN1 subunits and two GluN2A and/or GluN2B subunits. Due to the controversy regarding the differential role of GluN2A and GluN2B subunits in excitotoxic cell death, we investigated the role of GluN2B in the activation of pro-death signaling following an in vitro model of global ischemia, oxygen and glucose deprivation (OGD). For this purpose, we used GluN2B(-/-) mouse cortical cultures and observed that OGD-induced damage was reduced in these neurons, and partially prevented in wild-type rat neurons by a selective GluN2B antagonist. Notably, we found a crucial role of the C-terminal domain of the GluN2B subunit in triggering excitotoxic signaling. Indeed, expression of YFP-GluN2B C-terminus mutants for the binding sites to post-synaptic density protein 95 (PSD95), Ca(2+)-calmodulin kinase IIα (CaMKIIα) or clathrin adaptor protein 2 (AP2) failed to mediate neuronal death in OGD conditions. We focused on the GluN2B-CaMKIIα interaction and found a determinant role of this interaction in OGD-induced death. Inhibition or knock-down of CaMKIIα exerted a neuroprotective effect against OGD-induced death, whereas overexpression of this kinase had a detrimental effect. Importantly, in comparison with neurons overexpressing wild-type CaMKIIα, neurons overexpressing a mutant form of the kinase (CaMKII-I205K), unable to interact with GluN2B, were partially protected against OGD-induced damage. Taken together, our results identify crucial determinants in the C-terminal domain of GluN2B subunits in promoting neuronal death in ischemic conditions. These mechanisms underlie the divergent roles of the GluN2A- and GluN2B-NMDARs in determining neuronal fate in cerebral ischemia.
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- 2016
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45. Magnetic Precipitation: A New Platform for Protein Purification
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Inês Iria, João Gonçalves, Ana M. Manuel, Raquel Santos, Ana Luísa Carvalho, Catarina A. C. Madeira, Ana Paula Leandro, Ana C. A. Roque, DQ - Departamento de Química, and UCIBIO - Applied Molecular Biosciences Unit
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0106 biological sciences ,magnetic nanoparticles ,Hofmeister series ,medicine.drug_class ,Magnetic separation ,Monoclonal antibody ,01 natural sciences ,Applied Microbiology and Biotechnology ,Chromatography, Affinity ,Magnetics ,010608 biotechnology ,Protein purification ,medicine ,Chemical Precipitation ,Humans ,antibody purification ,Chromatography ,Downstream processing ,biology ,Chemistry ,Precipitation (chemistry) ,Magnetic Phenomena ,010401 analytical chemistry ,Antibodies, Monoclonal ,General Medicine ,downstream ,Culture Media ,0104 chemical sciences ,affinity magnetic precipitation ,Polyclonal antibodies ,biology.protein ,Molecular Medicine ,Magnetic nanoparticles ,method development - Abstract
PD/BD/105753/2014 UIDB/ 04378/2020 POCI-01-0145-FEDER-007728 PTDC/BII-BIO/28878/2017 One of the trends in downstream processing comprises the use of “anything-but-chromatography” methods to overcome the current downfalls of standard packed-bed chromatography. Precipitation and magnetic separation are two techniques already proven to accomplish protein purification from complex media, yet never used in synergy. With the aim to capture antibodies directly from crude extracts, a new approach combining precipitation and magnetic separation is developed and named as affinity magnetic precipitation. A precipitation screening, based on the Hofmeister series, and a commercial precipitation kit are tested with affinity magnetic particles to assess the best condition for antibody capture from human serum plasma and clarified cell supernatant. The best conditions are obtained when using PEG3350 as precipitant at 4 °C for 1 h, reaching 80% purity and 50% recovery of polyclonal antibodies from plasma, and 99% purity with 97% recovery yield of anti-TNFα mAb from cell supernatants. These results show that the synergetic use of precipitation and magnetic separation can represent an alternative for the efficient capture of antibodies. authorsversion published
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- 2020
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46. Target highlights from the first post-PSI CASP experiment (CASP12, May-August 2016)
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Shabir Najmudin, Johan C. Hill, Guido Pintacuda, Kinlin L. Chao, John Moult, Arnaud Baslé, T.H. Nguyen, Kaspars Tars, Harry J. Gilbert, Krzysztof Fidelis, Christopher S. Hayes, Marco Nardini, Reinhard Albrecht, Mark J. van Raaij, Valentina Nardone, Roman I. Koning, Celia W. Goulding, Pedro Bule, A.K. Singh, Nicole Zitzmann, Andrzej Joachimiak, Osnat Herzberg, Leila Lo Leggio, Carlos M. G. A. Fontes, Eric J. Sundberg, Pietro Roversi, Didier Ndeh, Andriy Kryshtafovych, Amir Shimon, Gert Wieland Kohring, Folmer Fredslund, Alessandro T. Caputo, Ana Luísa Carvalho, Marco Mangiagalli, Karolina Michalska, Sandra Postel, Marcus D. Hartmann, Torsten Schwede, Ron Diskin, Genome Center [UC Davis], University of California [Davis] (UC Davis), University of California-University of California, Abteilung Membranbiochemie [Martinsried], Max-Planck-Institut für Biochemie (MPIB), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Institute for Cell and Molecular Biosciences, Newcastle University [Newcastle], Interdisciplinary Centre of Research in Animal Health, Faculdade de Medicina Veterinária, Pólo Universitário do Alto da Ajuda, Universidade de Lisboa, Oxford Glycobiol Inst, Dept Biochem, University of Oxford [Oxford], Unidade de Ciencias Biomoleculares Aplicadas (UCIBIO), Requimte, Departamento de Química (DQ), Faculdade de Ciências e Tecnologia = School of Science & Technology (FCT NOVA), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Faculdade de Ciências e Tecnologia = School of Science & Technology (FCT NOVA), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade do Porto-Departamento de Química (DQ), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade Nova de Lisboa = NOVA University Lisbon (NOVA)-Universidade do Porto, Dept Mol Cellular & Dev Biol, University of California [Santa Barbara] (UCSB), Structural Biology Center, Biosciences Division, Universität des Saarlandes [Saarbrücken], Department of Chemistry, University of Copenhagenn, Department of Cell Biology and Molecular Genetics, University of Maryland [College Park], University of Maryland System-University of Maryland System, Department of Biomolecular Sciences and Biotechnology, University of Milano, Biological Solid-State NMR Methods - Méthodes de RMN à l'état solide en biologie, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Biomedical Research & Study Centre, Department of Biochemistry [Oxford], Biozentrum [Basel, Suisse], University of Basel (Unibas), Kryshtafovych, A, Albrecht, R, Baslé, A, Bule, P, Caputo, A, Carvalho, A, Chao, K, Diskin, R, Fidelis, K, Fontes, C, Fredslund, F, Gilbert, H, Goulding, C, Hartmann, M, Hayes, C, Herzberg, O, Hill, J, Joachimiak, A, Kohring, G, Koning, R, Lo Leggio, L, Mangiagalli, M, Michalska, K, Moult, J, Najmudin, S, Nardini, M, Nardone, V, Ndeh, D, Nguyen, T, Pintacuda, G, Postel, S, Van Raaij, M, Roversi, P, Shimon, A, Singh, A, Sundberg, E, Tars, K, Zitzmann, N, and Schwede, T
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0301 basic medicine ,Models, Molecular ,Protein Folding ,Protein Conformation ,Bioinformatics ,FIS/07 - FISICA APPLICATA (A BENI CULTURALI, AMBIENTALI, BIOLOGIA E MEDICINA) ,Computational biology ,computer.software_genre ,Crystallography, X-Ray ,Biochemistry ,Article ,Mathematical Sciences ,03 medical and health sciences ,Structural Biology ,Models ,Information and Computing Sciences ,[CHIM]Chemical Sciences ,Animals ,Humans ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,CASP ,Molecular Biology ,X-ray crystallography ,Physics ,Crystallography ,Bacteria ,Proteins ,Computational Biology ,Molecular ,Protein structure prediction ,Biological Sciences ,BIO/10 - BIOCHIMICA ,NMR ,protein structure prediction ,030104 developmental biology ,Biological significance ,X-Ray ,Data mining ,computer ,Software - Abstract
International audience; The functional and biological significance of the selected CASP12 targets are described by the authors of the structures. The crystallographers discuss the most interesting structural features of the target proteins and assess whether these features were correctly reproduced in the predictions submitted to the CASP12 experiment.
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- 2018
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47. Das CPCJ aos tribunais da relação : caracterização dos processos de promoção e proteção
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Pinto, Ana Luísa Carvalho and Xavier, Paula
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criança ,child ,rights ,medidas promoção e proteção ,protection and promotion measures ,tribunais ,courts ,CPCJ ,direitos - Abstract
O progressivo reconhecimento do lugar que as crianças e jovens ocupam na sociedade enquanto sujeitos de direitos e a importância de incentivar, desenvolver e assegurar o exercício efetivo dos mesmos, tem convocado os interventores políticos e sociais para a observância de boas práticas em matéria de infância e juventude. Mas nem sempre foi desta forma, e existirá ainda um longo caminho a percorrer no que respeita a esta temática. Neste trabalho foi feito o enquadramento da evolução dos direitos da criança até se chegar à intervenção no âmbito da Lei 147/99. Esta intervenção foi depois seguida, desde o seu início até à chegada a sede judicial, através da análise de 92 acórdãos que implicam a matéria de facto. Obtiveram-se resultados que apontam para a maior frequência da aplicabilidade das medidas de “confiança a instituição com vista a futura adoção” e “acolhimento residencial” pelos Tribunais de Família e Menores e da Relação. Também foi possível apurar que a maioria dos recursos são indeferidos pelos Tribunais de Relação. Este estudo aponta para a necessidade de intervenção precoce em matéria de promoção e protecção, para que se possam evitar muitas vezes situações remediativas que acontecem, assim como para a importância do trabalho de acompanhamento das famílias The progressive recognition of the place that children and young people have in society as subjects of rights and the importance of encourage, develop and secure its effective exercise, has summoned the political and social intervenors to observe good practices within childhood and youth. It hasn’t always been like this and there’s still a long way to run regarding this issue. In this report we’ve approached the children’s rights evolution until reaching the intervention under the law 147/99. This intervention has been followed since its beginning until reaching the judicial seat, through the analysis of judgements which imply this matter.Results were obtained which aim to a greater frequency of the applicability of measures related with “the trust on an institution regarding a future adoption” and “child residential reception”. Among other results, it was also possible to gather that most of the appeals are denied by Supreme Court. This study aims to the need of early intervention, which can avoid many of the fixing situations happening, as well as the importance of working with the families and families monitoring.
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- 2017
48. Jogos combinatórios em grafos: jogo Timber e jogo de Coloração
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Furtado, Ana Luísa Carvalho, Souza, Simone Dantas de, Gravier, Sylvain, Klein, Sulamita, Freitas, Maria Aguieiras Alvarez de, and Figueiredo, Celina Miraglia Herrera de
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CIENCIAS EXATAS E DA TERRA::CIENCIA DA COMPUTACAO::MATEMATICA DA COMPUTACAO [CNPQ] ,Teoria dos grafos ,Teoria dos jogos ,Otimização combinatória - Abstract
Submitted by Christianne Fontes de Andrade (cfontes@ct.ufrj.br) on 2019-02-06T17:03:32Z No. of bitstreams: 1 867856.pdf: 1592050 bytes, checksum: 89e69ef80dbfa30aaf3dfb3b20b44d77 (MD5) Made available in DSpace on 2019-02-06T17:03:32Z (GMT). No. of bitstreams: 1 867856.pdf: 1592050 bytes, checksum: 89e69ef80dbfa30aaf3dfb3b20b44d77 (MD5) Previous issue date: 2017-10 Estudo de três jogos combinatórios competitivos. O jogo timber é jogado em digrafos, sendo que cada arco representa um dominó, e o sentido do arco indica o sentido em que o mesmo pode ser derrubado, causando um efeito em cadeia. O jogador que derrubar o último dominó é o vencedor. Uma P-position é uma orientação das arestas de um grafo na qual o segundo jogador ganha. Se o grafo possui ciclos, então não há P-positions e, por este motivo, o jogo timber só é interessante quando jogado em árvores. Determinamos o número de P-positions em três famílias de caterpillars e um limite inferior para o número de P-positions em uma caterpillar qualquer. Além disto, provamos que uma árvore qualquer possui P-positions se, e somente se, possui quantidade par de arestas. No jogo de coloração, Alice e Bob se revezam colorindo propriamente os vértices de um grafo, sendo que Alice tenta minimizar o número de cores, enquanto Bob tenta maximizá-lo. O número cromático do jogo é o menor número de cores que garante que o grafo pode ser propriamente colorido apesar da intenção de Bob. Determinamos o número cromático do jogo para três subclasses de orestas (compostas por caterpillars), apresentamos duas condições su cientes e duas condições necessárias para qualquer caterpillar ter número cromático do jogo igual a 4. No jogo de marcação, Alice e Bob selecionam alternadamente os vértices não selecionados de um grafo, e Alice tenta garantir que para algum inteiro k, todo vértice não selecionado tem no máximo k − 1 vizinhos selecionados. O número de coloração do jogo é o menor k possível. Estabelecemos limites inferiores e superiores para a relação do tipo Nordhaus-Gaddum referente ao número de P-positions de uma caterpillar, aos números cromático e de coloração do jogo em um grafo qualquer. Studies three competitive combinatorial games. The timber game is played in digraphs, with each arc representing a domino, and the arc direction indicates the direction in which it can be toppled, causing a chain reaction. The player who topples the last domino is the winner. A P-position is an orientation of the edges of a graph in which the second player wins. If the graph has cycles, then the graph has no P-positions and, for this reason, timber game is only interesting when played in trees. We determine the number of P-positions in three caterpillar families and a lower bound for the number of P-positions in any caterpillar. Moreover, we prove that a tree has P-positions if, and only if, it has an even number of edges. In the coloring game, Alice and Bob take turns properly coloring the vertices of a graph, Alice trying to minimize the number of colors used, while Bob tries to maximize them. The game chromatic number is the smallest number of colors that ensures that the graph can be properly colored despite of Bob's intention. We determine the game chromatic number for three forest subclasses (composed by caterpillars), we present two su cient conditions and two necessary conditions for any caterpillar to have game chromatic number equal to 4. In the marking game, Alice and Bob take turns selecting the unselected vertices of a graph, and Alice tries to ensure that for some integer k, every unselected vertex has at most k − 1 neighbors selected. The game coloring number is the smallest k possible. We established lower and upper bounds for the Nordhaus-Gaddum type inequality for the number of P-positions of a caterpillar, the game chromatic and coloring numbers in any graph.
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- 2017
49. Liquid Crystals: Tunable Gas Sensing Gels by Cooperative Assembly (Adv. Funct. Mater. 27/2017)
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Ana Carolina Pádua, Ana C. A. Roque, Hugo Gamboa, Ana Teresa Silva Semeano, Jonas Gruber, José António de Almeida, Abid Hussain, Bárbara F. Medrado, Ana Sofia Pina, Rein V. Ulijn, Susana I. C. J. Palma, Rosamaria Wu Chia Li, Ana Luísa Carvalho, and Madalena Dionísio
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food.ingredient ,Materials science ,Nanotechnology ,Condensed Matter Physics ,Gelatin ,Electronic, Optical and Magnetic Materials ,Biomaterials ,chemistry.chemical_compound ,food ,chemistry ,Liquid crystal ,Ionic liquid ,Electrochemistry ,Self-assembly - Published
- 2017
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50. Tunable gas sensing gels by cooperative assembly
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Abid Hussain, Bárbara F. Medrado, Madalena Dionísio, Ana Teresa Silva Semeano, Hugo Gamboa, Jonas Gruber, Ana Carolina Pádua, Ana C. A. Roque, Ana Luísa Carvalho, José Roberto Fogaça de Almeida, Rein V. Ulijn, Rosamaria Wu Chia Li, Ana Sofia Pina, Susana I. C. J. Palma, DQ - Departamento de Química, UCIBIO - Applied Molecular Biosciences Unit, LAQV@REQUIMTE, DF – Departamento de Física, and LIBPhys-UNL
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gas sensing ,Fabrication ,food.ingredient ,Materials science ,genetic structures ,Supramolecular chemistry ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Gelatin ,Article ,gelatin ,ionic liquids ,Biomaterials ,chemistry.chemical_compound ,food ,liquid crystals ,Liquid crystal ,Electrochemistry ,self-assembly ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Small molecule ,0104 chemical sciences ,Characterization (materials science) ,Electronic, Optical and Magnetic Materials ,CRISTAIS LÍQUIDOS ,chemistry ,Ionic liquid ,Self-assembly ,0210 nano-technology - Abstract
European Research Council - SCENT-ERC-2014-STG-639123 POCI-01-0145-FEDER-007728 The cooperative assembly of biopolymers and small molecules can yield functional materials with precisely tunable properties. Here, the fabrication, characterization, and use of multicomponent hybrid gels as selective gas sensors are reported. The gels are composed of liquid crystal droplets self-assembled in the presence of ionic liquids, which further coassemble with biopolymers to form stable matrices. Each individual component can be varied and acts cooperatively to tune gels' structure and function. The unique molecular environment in hybrid gels is explored for supramolecular recognition of volatile compounds. Gels with distinct compositions are used as optical and electrical gas sensors, yielding a combinatorial response conceptually mimicking olfactory biological systems, and tested to distinguish volatile organic compounds and to quantify ethanol in automotive fuel. The gel response is rapid, reversible, and reproducible. These robust, versatile, modular, pliant electro-optical soft materials possess new possibilities in sensing triggered by chemical and physical stimuli. publishersversion published
- Published
- 2017
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