26 research outputs found
Cognitive stimulation of the default-mode network modulates functional connectivity in healthy aging
A cognitive-stimulation tool was created to regulate functional connectivity within the brain Default-Mode Network (DMN). Computerized exercises were designed based on the hypothesis that repeated task-dependent coactivation of multiple DMN regions would translate into regulation of resting-state network connectivity.
Forty seniors (mean age: 65.90 years; SD: 8.53) were recruited and assigned either to an experimental group (n = 21) who received one month of intensive cognitive stimulation, or to a control group (n = 19) who maintained a regime of daily-life activities explicitly focused on social interactions. An MRI protocol and a battery of neuropsychological tests were administered at baseline and at the end of the study. Changes in the DMN (measured via functional connectivity of posterior-cingulate seeds), in brain volumes, and in cognitive performance were measured with mixed models assessing group-by-timepoint interactions. Moreover, regression models were run to test gray-matter correlates of the various stimulation tasks.
Significant associations were found between task performance and gray-matter volume of multiple DMN core regions. Training-dependent up-regulation of functional connectivity was found in the posterior DMN component. This interaction was driven by a pattern of increased connectivity in the training group, while little or no up-regulation was seen in the control group. Minimal changes in brain volumes were found, but there was no change in cognitive performance.
The training-dependent regulation of functional connectivity within the posterior DMN component suggests that this stimulation program might exert a beneficial impact in the prevention and treatment of early AD neurodegeneration, in which this neurofunctional pathway is progressively affected by the disease
REGULUS CubeSat Propulsion System: In-Orbit Operations
A robust, versatile, and cost-effective propulsion system to provide wide mobility to small satellite platforms and nanosatellite deployers. A Plug&Play propulsion system designed to be easily integrated into different satellite platforms and to match customer\u27s requirements, with minimal customization efforts and costs
Left amygdala and putamen activation modulate emotion driven decisions in the iterated Prisoner’s Dilemma game
Although economic decision-making is commonly characterized as a purely rational phenomenon, it is clear that real-world decision-making is influenced by emotions. Yet, relatively little is known about the neural correlates of this process. To explore this issue, 20 participants underwent fMRI scanning while engaged in the Prisoner’s Dilemma game under partner-directed sympathy, anger and neutral emotion conditions. Participants were most and least likely to cooperate after sympathy and anger induction, respectively, with the neutral condition eliciting intermediate cooperation rates. Moreover, the sympathy condition elicited quicker responses for cooperation than defection choices, whereas this pattern was reversed in the anger and neutral conditions. Left amygdala activation showed a positive correlation with cooperation rates and self-reports of partner directed sympathy in the sympathy condition. In the anger condition, left putamen activation was positively correlated with cooperation rates and negatively correlated with self-reports of partner directed anger strength. These findings indicate that while the left amygdala activation may be indicative of emotion enhancement and increase of cooperative behavior, the left putamen may help to suppress an emotion to overcome anger and engage in cooperation
Ballonnen in zee = balloons as marine litter
Releasing balloons seems harmless. However, remains of balloons, especially valves and ribbons are becoming a common and persistent type of marine litter found on beaches. Following Dutch Queens day 2007, large numbers of Dutch balloons were found in Normandy, France. Animals may become entangled in ribbons or ingest the materials. Even though balloon rubber quickly disintegrates, remains are found in 1-2% of stomachs of Northern Fulmars beached in the North Sea area. Children¿s contests, releasing balloons with name tags, are not the real problem, especially if no plastic valves and short, degradable ribbons are used. However, the vast majority of balloons released is meant for company advertising and provide just a very short moment of joy followed by a nuisance in the marine environment. environmentally friendly companies may want to reconsider such activities in future
Meta-analysis of neural systems underlying placebo analgesia from individual participant fMRI data
The brain systems underlying placebo analgesia are insufficiently understood. Here we performed a systematic, participant-level meta-analysis of experimental functional neuroimaging studies of evoked pain under stimulus-intensity-matched placebo and control conditions, encompassing 603 healthy participants from 20 (out of 28 eligible) studies. We find that placebo vs. control treatments induce small, widespread reductions in pain-related activity, particularly in regions belonging to ventral attention (including mid-insula) and somatomotor networks (including posterior insula). Behavioral placebo analgesia correlates with reduced pain-related activity in these networks and the thalamus, habenula, mid-cingulate, and supplementary motor area. Placebo-associated activity increases occur mainly in frontoparietal regions, with high between-study heterogeneity. We conclude that placebo treatments affect pain-related activity in multiple brain areas, which may reflect changes in nociception and/or other affective and decision-making processes surrounding pain. Between-study heterogeneity suggests that placebo analgesia is a multi-faceted phenomenon involving multiple cerebral mechanisms that differ across studies
Meta-analysis of neural systems underlying placebo analgesia from individual participant fMRI data
The brain systems underlying placebo analgesia are insufficiently understood. Here we performed a systematic, participant-level meta-analysis of experimental functional neuroimaging studies of evoked pain under stimulus-intensity-matched placebo and control conditions, encompassing 603 healthy participants from 20 (out of 28 eligible) studies. We find that placebo vs. control treatments induce small, widespread reductions in pain-related activity, particularly in regions belonging to ventral attention (including mid-insula) and somatomotor networks (including posterior insula). Behavioral placebo analgesia correlates with reduced pain-related activity in these networks and the thalamus, habenula, mid-cingulate, and supplementary motor area. Placebo-associated activity increases occur mainly in frontoparietal regions, with high between-study heterogeneity. We conclude that placebo treatments affect pain-related activity in multiple brain areas, which may reflect changes in nociception and/or other affective and decision-making processes surrounding pain. Between-study heterogeneity suggests that placebo analgesia is a multi-faceted phenomenon involving multiple cerebral mechanisms that differ across studies
[des-arg(1)]-proctolin: A Novel Nep-like Enzyme Inhibitor Identified In Tityus Serrulatus Venom
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)The scorpion Tityus serrulatus venom comprises a complex mixture of molecules that paralyzes and kills preys, especially insects. However, venom components also interact with molecules in humans, causing clinic envenomation. This cross-interaction may result from homologous molecular targets in mammalians and insects, such as (NEP)-like enzymes. In face of these similarities, we searched for peptides in Tityus serrulatus venom using human NEP as a screening tool. We found a NEP-inhibiting peptide with the primary sequence YLPT, which is very similar to that of the insect neuropeptide proctolin (RYLPT). Thus, we named the new peptide [des-Arg(1)]-proctolin. Comparative NEP activity assays using natural substrates demonstrated that [des-Arg(1)]-proctolin has high specificity for NEP and better inhibitory activity than proctolin. To test the initial hypothesis that molecular homologies allow Tityus serrulatus venom to act on both mammal and insect targets, we investigated the presence of a NEP-like in cockroaches, the main scorpion prey, that could be likewise inhibited by [des-Arg(1)]-proctolin. Indeed, we detected a possible NEP-like in a homogenate of cockroach heads whose activity was blocked by thiorphan and also by [des-Arg(1)]-proctolin. Western blot analysis using a human NEP monoclonal antibody suggested a NEP-like enzyme in the homogenate of cockroach heads. Our study describes for the first time a proctolin-like peptide, named [des-Arg(1)]-proctolin, isolated from Tityus serrulatus venom. The tetrapeptide inhibits human NEP activity and a NEP-like activity in a cockroach head homogenate, thus it may play a role in human envenomation as well as in the paralysis and death of scorpion preys. (C) 2015 Elsevier Inc. All rights reserved.801824Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [2014/12976-5, 2012/06677-0, 2013/15343-0]Instituto Nacional de Ciencia e Tecnologia em Toxinas-Conselho Nacional de Desenvolvimento Cientifico e TecnologicoConselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq