13 documents found, page 1 of 2
A 2 Adenosine Receptors Mediate Whole-Body Insulin Sensitivity in a Prediabetes...
Sacramento, Joana F.; Martins, Fátima O.; Rodrigues, Tiago; Matafome, Paulo N.; Ribeiro, Maria J.; Olea, Elena; Conde, Sílvia V.Epidemiological studies showed that chronic caffeine intake decreased the risk of type 2 diabetes. Previously, we described that chronic caffeine intake prevents and reverses insulin resistance induced by hypercaloric diets and aging, in rats. Caffeine has several cellular mechanisms of action, being the antagonism of adenosine receptors the only attained with human coffee consumption. Here, we investigated the...
A Novel Ecological Approach Reveals Early Executive Function Impairments in Hun...
Júlio, Filipa; Ribeiro, Maria J.; Patrício, Miguel; Malhão, Alexandre; Pedrosa, Fábio; Gonçalves, Hélio; Simões, Marco; van Asselen, MariekeIntroduction: Impairments in executive functions are common in neurogenetic disorders such as Huntington's disease (HD) and are thought to significantly influence the patient's functional status. Reliable tools with higher ecological validity that can assess and predict the impact of executive dysfunction in daily-life performance are needed. This study aimed to develop and validate a novel non-immersive virtua...
Evaluating the Impact of Different Hypercaloric Diets on Weight Gain, Insulin R...
Melo, Bernardete F.; Sacramento, Joana F.; Ribeiro, Maria J.; Prego, Claudia S.; Correia, Miguel C.; Coelho, Joana C.; Cunha-Guimaraes, Joao P.Animal experimentation has a long history in the study of metabolic syndrome-related disorders. However, no consensus exists on the best models to study these syndromes. Knowing that different diets can precipitate different metabolic disease phenotypes, herein we characterized several hypercaloric rat models of obesity and type 2 diabetes, comparing each with a genetic model, with the aim of identifying the mo...
High fat diet blunts the effects of leptin on ventilation and on carotid body a...
Ribeiro, Maria J.; Sacramento, Joana F.; Gallego‐Martin, Teresa; Olea, Elena; Melo, Bernardete F.; Guarino, Maria Pedro; Yubero, Sara; Obeso, AnaKey points Leptin plays a role in the control of breathing, acting mainly on central nervous system; however, leptin receptors have been recently shown to be expressed in the carotid body (CB), and this finding suggests a physiological role for leptin in the regulation of CB function. Leptin increases minute ventilation in both basal and hypoxic conditions in rats. It increases the frequency of carotid sinus ne...
Spontaneous Fluctuations in Sensory Processing Predict Within-Subject Reaction ...
Ribeiro, Maria J.; Paiva, Joana S; Castelo-Branco, MiguelWhen engaged in a repetitive task our performance fluctuates from trial-to-trial. In particular, inter-trial reaction time variability has been the subject of considerable research. It has been claimed to be a strong biomarker of attention deficits, increases with frontal dysfunction, and predicts age-related cognitive decline. Thus, rather than being just a consequence of noise in the system, it appears to be ...
Peripheral Attentional Targets under Covert Attention Lead to Paradoxically Enh...
Silva, Gilberto; Ribeiro, Maria J.; Costa, Gabriel N; Violante, Inês; Ramos, Fabiana; Saraiva, Jorge; Castelo-Branco, MiguelThe limited capacity of the human brain to process the full extent of visual information reaching the visual cortex requires the recruitment of mechanisms of information selection through attention. Neurofibromatosis type-1 (NF1) is a neurodevelopmental disease often exhibiting attentional deficits and learning disabilities, and is considered to model similar impairments common in other neurodevelopmental disor...
Abnormal relationship between GABA, neurophysiology and impulsive behavior in n...
Ribeiro, Maria J.; Violante, Inês R; Bernardino, Inês; Edden, Richard A E; Castelo-Branco, MiguelNeurofibromatosis type 1 (NF1) is a neurodevelopmental disorder characterized by a broad spectrum of cognitive deficits. In particular, executive dysfunction is recognized as a core deficit of NF1, including impairments in executive attention and inhibitory control. Yet, the neural mechanisms behind these important deficits are still unknown. Here, we studied inhibitory control in a visual go/no-go task in chil...
Activation of IGF-1 and Insulin Signaling Pathways Ameliorate Mitochondrial Fun...
Naia, Luana; Ferreira, I. Luísa; Cunha-Oliveira, Teresa; Duarte, Ana I.; Ribeiro, Márcio; Rosenstock, Tatiana R.; Laço, Mário N.; Ribeiro, Maria J.Huntington's disease (HD) is an inherited neurodegenerative disease caused by a polyglutamine repeat expansion in the huntingtin protein. Mitochondrial dysfunction associated with energy failure plays an important role in this untreated pathology. In the present work, we used lymphoblasts obtained from HD patients or unaffected parentally related individuals to study the protective role of insulin-like growth f...
Oxidative stress mechanisms caused by ag nanoparticles (NM300K) are different f...
Ribeiro, Maria J.; Maria, Vera L.; Scott-Fordsmand, Janeck J.; Amorim, Mónica J. B.The mechanisms of toxicity of Ag nanoparticles (NPs) are unclear, in particular in the terrestrial environment. In this study the effects of AgNP (AgNM300K) were assessed in terms of oxidative stress in the soil worm Enchytraeus crypticus, using a range of biochemical markers [catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR), total glutathione (TG), metal...
Abnormal late visual responses and alpha oscillations in neurofibromatosis type...
Ribeiro, Maria J.; Almeida, Otília C. d'; Ramos, Fabiana; Saraiva, Jorge; Silva, Eduardo D.; Castelo-Branco, MiguelNeurofibromatosis type 1 (NF1) affects several areas of cognitive function including visual processing and attention. We investigated the neural mechanisms underlying the visual deficits of children and adolescents with NF1 by studying visual evoked potentials (VEPs) and brain oscillations during visual stimulation and rest periods.; This work was funded by the Institute of Interdisciplinary Research of the Uni...