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1.
Annu Rev Neurosci ; 45: 361-386, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35385670

RESUMO

Cognitive neuroscience has highlighted the cerebral cortex while often overlooking subcortical structures. This cortical proclivity is found in basic and translational research on many aspects of cognition, especially higher cognitive domains such as language, reading, music, and math. We suggest that, for both anatomical and evolutionary reasons, multiple subcortical structures play substantial roles across higher and lower cognition. We present a comprehensive review of existing evidence, which indeed reveals extensive subcortical contributions in multiple cognitive domains. We argue that the findings are overall both real and important. Next, we advance a theoretical framework to capture the nature of (sub)cortical contributions to cognition. Finally, we propose how new subcortical cognitive roles can be identified by leveraging anatomical and evolutionary principles, and we describe specific methods that can be used to reveal subcortical cognition. Altogether, this review aims to advance cognitive neuroscience by highlighting subcortical cognition and facilitating its future investigation.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Córtex Cerebral , Cognição , Frutas
2.
PLoS Comput Biol ; 18(6): e1010182, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35731822

RESUMO

Internal models capture the regularities of the environment and are central to understanding how humans adapt to environmental statistics. In general, the correct internal model is unknown to observers, instead they rely on an approximate model that is continually adapted throughout learning. However, experimenters assume an ideal observer model, which captures stimulus structure but ignores the diverging hypotheses that humans form during learning. We combine non-parametric Bayesian methods and probabilistic programming to infer rich and dynamic individualised internal models from response times. We demonstrate that the approach is capable of characterizing the discrepancy between the internal model maintained by individuals and the ideal observer model and to track the evolution of the contribution of the ideal observer model to the internal model throughout training. In particular, in an implicit visuomotor sequence learning task the identified discrepancy revealed an inductive bias that was consistent across individuals but varied in strength and persistence.


Assuntos
Atenção , Aprendizagem , Teorema de Bayes , Viés , Humanos , Aprendizagem/fisiologia
3.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35162960

RESUMO

Inhibition of the human O-linked ß-N-acetylglucosaminidase (hOGA, GH84) enzyme is pharmacologically relevant in several diseases such as neurodegenerative and cardiovascular disorders, type 2 diabetes, and cancer. Human lysosomal hexosaminidases (hHexA and hHexB, GH20) are mechanistically related enzymes; therefore, selective inhibition of these enzymes is crucial in terms of potential applications. In order to extend the structure-activity relationships of OGA inhibitors, a series of 2-acetamido-2-deoxy-d-glucono-1,5-lactone sulfonylhydrazones was prepared from d-glucosamine. The synthetic sequence involved condensation of N-acetyl-3,4,6-tri-O-acetyl-d-glucosamine with arenesulfonylhydrazines, followed by MnO2 oxidation to the corresponding glucono-1,5-lactone sulfonylhydrazones. Removal of the O-acetyl protecting groups by NH3/MeOH furnished the test compounds. Evaluation of these compounds by enzyme kinetic methods against hOGA and hHexB revealed potent nanomolar competitive inhibition of both enzymes, with no significant selectivity towards either. The most efficient inhibitor of hOGA was 2-acetamido-2-deoxy-d-glucono-1,5-lactone 1-naphthalenesulfonylhydrazone (5f, Ki = 27 nM). This compound had a Ki of 6.8 nM towards hHexB. To assess the binding mode of these inhibitors to hOGA, computational studies (Prime protein-ligand refinement and QM/MM optimizations) were performed, which suggested the binding preference of the glucono-1,5-lactone sulfonylhydrazones in an s-cis conformation for all test compounds.


Assuntos
Antígenos de Neoplasias/química , Histona Acetiltransferases/química , Hialuronoglucosaminidase/química , Hidrazonas/síntese química , Lactonas/química , Cadeia beta da beta-Hexosaminidase/química , Antígenos de Neoplasias/metabolismo , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Histona Acetiltransferases/metabolismo , Humanos , Hialuronoglucosaminidase/metabolismo , Hidrazonas/química , Hidrazonas/farmacologia , Compostos de Manganês/química , Modelos Moleculares , Conformação Molecular , Óxidos/química , Relação Estrutura-Atividade , Cadeia beta da beta-Hexosaminidase/metabolismo
4.
Cortex ; 157: 65-80, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36274443

RESUMO

Ample evidence shows that the momentary performance can dissociate from the underlying knowledge (competence). Under what circumstances such dissociation occurs, however, remains unclear. Here we tested how temporal factors, and more specifically, the elapsed time between subsequent events affects the dissociation between performance and competence by systematically manipulating the stimulus presentation rates during and after learning. Participants completed a probabilistic sequence learning task with a fast (120 msec) or a slow (850 msec) response-to-stimulus-interval (RSI) during the Learning phase and they were tested with both RSIs 24 h later (Testing phase). We also tested whether they gained explicit knowledge about the sequence or their knowledge remained implicit. Our results revealed higher reaction time learning scores when tested with the fast RSI, irrespective of the RSI during learning, suggesting that faster presentation rates can help better express the acquired knowledge, leading to increased performance measures. For accuracy, participants showed higher learning scores when tested with the same presentation rate as the one that they encountered during learning. The acquired knowledge remained implicit in both groups, suggesting that the observed findings were not confounded by differences in awareness gained in the two groups. Overall, our study highlights that the momentary performance does not always accurately reflect the underlying knowledge, and temporal factors seem to influence this dissociation. Our findings have theoretical, methodological, and translational implications that likely extend beyond learning and memory to other functions and domains as well, including aspects of decision-making, perception, theory of mind, and language.


Assuntos
Conhecimento , Aprendizagem Seriada , Humanos , Tempo de Reação , Aprendizagem , Condicionamento Operante
5.
NPJ Sci Learn ; 6(1): 14, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210989

RESUMO

Knowing when the brain learns is crucial for both the comprehension of memory formation and consolidation and for developing new training and neurorehabilitation strategies in healthy and patient populations. Recently, a rapid form of offline learning developing during short rest periods has been shown to account for most of procedural learning, leading to the hypothesis that the brain mainly learns during rest between practice periods. Nonetheless, procedural learning has several subcomponents not disentangled in previous studies investigating learning dynamics, such as acquiring the statistical regularities of the task, or else the high-order rules that regulate its organization. Here we analyzed 506 behavioral sessions of implicit visuomotor deterministic and probabilistic sequence learning tasks, allowing the distinction between general skill learning, statistical learning, and high-order rule learning. Our results show that the temporal dynamics of apparently simultaneous learning processes differ. While high-order rule learning is acquired offline, statistical learning is evidenced online. These findings open new avenues on the short-scale temporal dynamics of learning and memory consolidation and reveal a fundamental distinction between statistical and high-order rule learning, the former benefiting from online evidence accumulation and the latter requiring short rest periods for rapid consolidation.

6.
Eur J Med Chem ; 223: 113649, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34186233

RESUMO

O-GlcNAcylation is a dynamic post-translational modification mediated by O-linked ß-N-acetylglucosamine transferase (OGT) and O-GlcNAc hydrolase (OGA), that adds or removes a single ß-N-acetylglucosamine (GlcNAc) moiety to or from serine/threonine residues of nucleocytosolic and mitochondrial proteins, respectively. The perturbed homeostasis of O-GlcNAc cycling results in several pathological conditions. Human OGA is a promising therapeutic target in diseases where aberrantly low levels of O-GlcNAc are experienced, such as tauopathy in Alzheimer's disease. A new class of potent OGA inhibitors, 2-acetamido-2-deoxy-d-glucono-1,5-lactone (thio)semicarbazones, have been identified. Eight inhibitors were designed and synthesized in five steps starting from d-glucosamine and with 15-55% overall yields. A heterologous OGA expression protocol with strain selection and isolation has been optimized that resulted in stable, active and full length human OGA (hOGA) isomorph. Thermal denaturation kinetics of hOGA revealed environmental factors affecting hOGA stability. From kinetics experiments, the synthesized compounds proved to be efficient competitive inhibitors of hOGA with Ki-s in the range of ∼30-250 nM and moderate selectivity with respect to lysosomal ß-hexosaminidases. In silico studies consisting of Prime protein-ligand refinements, QM/MM optimizations and QM/MM-PBSA binding free energy calculations revealed the factors governing the observed potencies, and led to design of the most potent analogue 2-acetamido-2-deoxy-d-glucono-1,5-lactone 4-(2-naphthyl)-semicarbazone 6g (Ki = 36 nM). The protocol employed has applications in future structure based inhibitor design targeting OGA.


Assuntos
Antígenos de Neoplasias/metabolismo , Inibidores Enzimáticos/química , Histona Acetiltransferases/metabolismo , Hialuronoglucosaminidase/metabolismo , Lactonas/química , Semicarbazonas/química , Antígenos de Neoplasias/genética , Sítios de Ligação , Inibidores Enzimáticos/metabolismo , Histona Acetiltransferases/antagonistas & inibidores , Histona Acetiltransferases/genética , Humanos , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/genética , Cinética , Ligantes , Simulação de Dinâmica Molecular , Ligação Proteica , Estabilidade Proteica , Teoria Quântica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Semicarbazonas/metabolismo , Relação Estrutura-Atividade
7.
Health Qual Life Outcomes ; 8: 14, 2010 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-20109201

RESUMO

OBJECTIVES: The aim of the study was to investigate the psychometric properties of the Hungarian version of the Pediatric Quality of Life Inventory (PedsQL) Generic Core Scales and Cardiac Module. METHODS: The PedsQL 4.0 Generic Core Scales and the PedsQL 3.0 Cardiac Module was administered to 254 caregivers of children (aged 2-18 years) and to 195 children (aged 5-18 years) at a pediatric cardiology outpatient unit. A postal survey on a demographically group-matched sample of the general population with 525 caregivers of children (aged 2-18 years) and 373 children (aged 5-18 years) was conducted with the PedsQL 4.0 Generic Core Scale. Responses were described, compared over subgroups of subjects, and were used to assess practical utility, distributional coverage, construct validity, internal consistency, and inter-reporter agreement of the instrument. RESULTS: The moderate scale-level mean percentage of missing item responses (range 1.8-2.3%) supported the feasibility of the Generic Core Scales for general Hungarian children. Minimal to moderate ceiling effects and no floor effects were found on the Generic Core Scales. We observed stronger ceiling than floor effects in the Cardiac Module. Most of the scales showed satisfactory reliability with Cronbach's alpha estimates exceeding 0.70. Generally, moderate to good agreement was found between self- and parent proxy-reports in the patient and in the comparison group (intraclass correlation coefficient range 0.52-0.77), but remarkably low agreement in the perceived physical appearance subscale in the age group 5-7 years (0.18) and for the treatment II scale (problems on taking heart medicine) scale of the Cardiac Module in children aged 8-12 years (0.39). Assessing the construct validity of the questionnaires, statistically significant difference was found between the patient group and the comparison group only in the Physical Functioning Scale scores (p = 0.003) of the child self-report component, and in Physical (p = 0.022), Emotional, (p = 0.017), Psychosocial Summary (p = 0.019) scores and in the total HRQoL (health-related quality of life) scale score (p = 0.034) for parent proxy-report. CONCLUSION: The findings generally support the feasibility, reliability and validity of the Hungarian translation of the PedsQL 4.0 Generic Core Scales and the PedsQL 3.0 Cardiac Module in Hungarian children with heart disease.


Assuntos
Cardiopatias/psicologia , Pediatria , Psicometria/métodos , Qualidade de Vida/psicologia , Adolescente , Cuidadores/psicologia , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Cardiopatias/fisiopatologia , Humanos , Hungria , Masculino , Reprodutibilidade dos Testes
8.
Orv Hetil ; 149(48): 2261-8, 2008 Nov 30.
Artigo em Húngaro | MEDLINE | ID: mdl-19028648

RESUMO

UNLABELLED: The authors report the validation process of the cardiac module of the Pediatric Quality of Life Inventory (PedsQL ) into Hungarian. BACKGROUND: The PedsQL which is a modular instrument to evaluate health-related quality of life (HRQL ) in children and adolescents of ages 2-18 years, comes up to the current professional requirements at a high level. There is no report on health-related quality of life measure in Hungary which was performed among children with heart disease. OBJECTIVE: To adapt and to test a pediatric quality of life questionnaire for measuring HRQL in children with heart disease. METHODS: Sequential validation process which follows international guidelines. Pilot-study on 105 children with heart disease. RESULTS: According to the results of the pilot-study the psychic domains have a negative influence on general HRQL index in both child and parent-proxy reports in all age groups. On the cardiac module parents of children of all age groups but only children of ages 5-7 years reported marked treatment anxiety. Cognitive and communication problems are mainly important for children of ages 8-18 years. Parent-child concordance is depending on the age of the child, there was expressed difference in the psychosocial domains. We have found no negative effect of heart operation on HRQL by itself but taking medicine may impair it. CONCLUSION: Further methodologic research should evaluate the psychometric properties of the newly validated Hungarian version of the PedsQL cardiac module. The detailed report about the validation process can help in the spreading of patient reported outcome measures in Hungary.


Assuntos
Cardiopatias , Saúde Mental , Qualidade de Vida , Inquéritos e Questionários/normas , Atividades Cotidianas , Adolescente , Ansiedade/etiologia , Criança , Pré-Escolar , Cognição , Transtornos Cognitivos/etiologia , Comunicação , Feminino , Nível de Saúde , Cardiopatias/complicações , Cardiopatias/psicologia , Cardiopatias/terapia , Humanos , Hungria , Masculino , Pediatria , Projetos Piloto , Psicometria , Índice de Gravidade de Doença , Perfil de Impacto da Doença
9.
J Inorg Biochem ; 177: 198-210, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28972934

RESUMO

The results of electrochemical and SOD activity measurements of such copper(II) complexes of terminally protected multihistidine peptides that may mimic the active site of CuZnSOD enzyme are submitted and completed with solution equilibrium studies of some copper(II)-ligand systems. The equilibrium data confirm that the thermodynamic stabilities increase with the increasing number of histidyl residues in the amino acid sequence, the stability order, however, can be finely tuned by the number and quality of amino acids between histidine residues. Based on the cyclic voltammetric studies we concluded that the formal reduction potential values of imidazole nitrogen coordinated complexes decrease with the increasing number of imidazole donor atoms in the coordination sphere. However, the redox parameters of [CuH-1L]+ and [CuH-2L] complexes containing amide nitrogen coordination can be determined as well. All formal potential values of [CuL]2+, [CuH-1L]+ and [CuH-2L] complexes fall in the middle potential range of SOD activity. Finally, after the detailed analysis of species distribution curves based upon the equilibrium data SOD activity of copper(II) containing systems at two pH (pH=6.8 and 7.4) were determined. The imidazole coordinated [CuL]2+ complexes of the multihistidine peptide containing the HXH sequence exhibit the most significant activity, but the presence of amide nitrogen coordinated species with slightly distorted geometry could considerably contribute to the SOD activity.


Assuntos
Materiais Biomiméticos/química , Complexos de Coordenação/química , Cobre/química , Histidina/química , Oligopeptídeos/química , Sequência de Aminoácidos , Animais , Domínio Catalítico , Bovinos , Concentração de Íons de Hidrogênio , Ligantes , Estrutura Molecular , Oxirredução , Superóxido Dismutase/química
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