Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability

The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.Fil: Nogueira Campos, Anaelli A.. Universidade Federal de Juiz de Fora; BrasilFil: Saunier, Ghislain. Universidade Federal do Pará; BrasilFil: Della Maggiore, Valeria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: De Oliveira, Laura A. S.. Centro Universitário Augusto Motta; BrasilFil: Rodrigues, Erika C.. Centro Universitário Augusto Motta; BrasilFil: Vargas, Claudia D.. Universidade Federal do Rio de Janeiro; Brasi

Retrieving the structure of probabilistic sequences of auditory stimuli from EEG data

Using a new probabilistic approach we model the relationship between sequences of auditory stimuli generated by stochastic chains and the electroencephalographic (EEG) data acquired while 19 participants were exposed to those stimuli. The structure of the chains generating the stimuli are characterized by rooted and labeled trees whose leaves, henceforth called contexts, represent the sequences of past stimuli governing the choice of the next stimulus. A classical conjecture claims that the brain assigns probabilistic models to samples of stimuli. If this is true, then the context tree generating the sequence of stimuli should be encoded in the brain activity. Using an innovative statistical procedure we show that this context tree can effectively be extracted from the EEG data, thus giving support to the classical conjecture.Comment: 16 pages, 7 figure

Is heart rate variability affected by distinct motor imagery strategies

Although some studies have reported significant changes in autonomic responses according to the perspective-taking during motor imagery [first person perspective (1P) and third person perspective (3P)], investigations on how the strategies adopted to mentally simulate a given movement affect the heart rate variability (HRV) seem so far unexplored. Twenty healthy subjects mentally simulated the movement of middle-finger extension in 1P and 3P, while electrocardiogram was recorded. After each task, the level of easiness was self-reported. Motor imagery ability was also assessed through the revised version of Movement Imagery Questionnaire (MIQ-R) and a mental chronometry index. The traditional measures of HRV in the time- and frequency-domain were compared between 1P and 3P tasks by using Student's t-test for dependent samples. The MIQ-R results showed that subjects had the same facility to imagine movements in 1P or 3P. The mental chronometry index revealed a similar temporal course only between 1P and execution, while the 3P strategy had a shorter duration. Additionally, the subjective report was similar between the experimental tasks. Regarding the HRV measures, the low frequency component, in log-transformed unit, was significantly higher (p=0.017) in 1P than 3P, suggesting a higher activity of the sympathetic system during 1P. This log-transformed HRV parameter seems to be more sensitive than normalized values for the assessment of the motor imagery ability, together with questionnaires, scales and mental chronometry

Altered immune parameters in chronic alcoholic patients at the onset of infection and of septic shock

INTRODUCTION: Chronic alcoholic patients have a threefold to fourfold increased risk for developing a severe infection or septic shock after surgery, which might be due to altered immune response. The aim of this outcome matched study was to investigate proinflammatory and anti-inflammatory immune parameters during the course of infection and subsequent septic shock in chronic alcoholic patients, and to compare these parameters with those in nonalcoholic patients. METHODS: Twenty-eight patients from a cohort of fifty-six with either pneumonia or peritonitis and subsequent septic shock were selected. Fourteen patients were chronic alcoholics whereas fourteen were nonalcoholic patients. Chronic alcoholic patients met criteria (Diagnostic and Statistical Manual of Mental Disorders IV, of the American Psychiatric Association) for alcohol abuse or dependence. Measurements were performed during the onset of infection (within 24 hours after the onset of infection), in early septic shock (within 12 hours after onset of septic shock) and in late septic shock (72 hours after the onset). Blood measurements included proinflammatory and anti-inflammatory cytokines. RESULTS: Chronic alcoholic patients exhibited significantly lower plasma levels of IL-8 (P < 0.010) during the onset of infection than did matched nonalcoholic patients. In early septic shock, chronic alcoholic patients had significantly decreased levels of IL-1β (P < 0.015), IL-6 (P < 0.016) and IL-8 (P < 0.010). The anti-inflammatory parameters IL-10 and tumour necrosis factor receptors I and II did not differ between alcoholic and nonalcoholic patients. CONCLUSION: At the onset of infection and during early septic shock, chronic alcoholic patients had lower levels of proinflammatory immune parameters than did nonalcoholic patients. Therefore, immunomodulatory therapy administered early may be considered in chronic alcoholic patients at the onset of an infection because of their altered proinflammatory immune response

Plasticity in the Brain after a Traumatic Brachial Plexus Injury in Adults

In this chapter, we aim to discuss the neurophysiological basis of the brain reorganization (also called plasticity) that associates with a traumatic brachial plexus injury (TBPI), as well as following the brachial plexus surgical reconstruction and its physical rehabilitation. We start by reviewing core aspects of plasticity following peripheral injuries such as amputation and TBPI as well as those associated with chronic pain conditions. Then, we present recent results collected by our team centered on physiological measurements of plasticity after TBPI. Finally, we discuss that an important limitation in the field is the lack of systematic measurement of TBPI clinical features. We finish by proposing possible future venues in the domain of brain plasticity following a TBPI

Sugar content and nutritional quality of child orientated ready to eat cereals and yoghurts in the UK and Latin America; does food policy matter?

Ready to eat breakfast cereals (REBCs) and yoghurts provide important nutrients to children’s diets, but concerns about their high sugar content exist. Food reformulation could contribute to sugar reduction, but policies across countries are not uniform. We aimed to compare the sugar content and nutritional quality of child-orientated REBCs and yoghurts in Latin American countries with the UK. In a cross-sectional study, nutritional information, marketing strategies, and claims were collected from the food labels and packaging of products available in Guatemala, Mexico, Ecuador and the UK. Nutritional quality was assessed using the UK Ofcom Nutrient Profiling System. In total, 262 products were analysed (59% REBCs/41% yoghurts). REBCs in the UK had a lower sugar content (mean ± SD) (24.6 ± 6.4) than products in Ecuador (34.6 ± 10.8; p &lt; 0.001), Mexico (32.6 ± 7.6; p = 0.001) and Guatemala (31.5 ± 8.3; p = 0.001). Across countries, there were no differences in the sugar content of yoghurts. A large proportion (83%) of REBCs and 33% of yoghurts were classified as “less healthy”. In conclusion, the sugar content of REBCs in Latin America is higher than those of the UK, which could be attributed to the UK voluntary sugar reduction programme. Sugar reformulation policies are required in Guatemala, Mexico and Ecuador

Effects of dopexamine on the intestinal microvascular blood flow and leucocyte activation in a sepsis model in rats

INTRODUCTION: Dopexamine may be a therapeutic option to improve hepatosplanchnic perfusion in sepsis. To investigate this possibility, we administered dopexamine in an experimental sepsis model in rats. METHODS: This prospective, randomized, controlled laboratory study was conducted in 42 Wistar rats. The animals were divided into three groups. Group 1 served as the control group (CON group). The animals in both groups 2 (LPS group) and 3 (DPX group) received an endotoxin (lipopolysaccharide from Escherichia coli – LPS) infusion (20 mg/kg for 15 minutes). DPX group additionally received dopexamine (0.5 μg/kg per minute over four hours). One half of the animals in each group underwent studies of intestinal microvascular blood flow (IMBF) using laser Doppler fluxmetry. In the other half an intravital microscopic evaluation of leucocyte-endothelial cell interaction in intestinal microcirculation was conducted. Functional capillary density (FCD) in the intestinal mucosa and in the circular as well as longitudinal muscle layer was estimated. RESULTS: One hour after endotoxin challenge, IMBF decreased significantly in LPS group to 51% compared with baseline (P < 0.05). In DPX group (endotoxin plus dopexamine) we found IMBF values significantly higher than those in LPS group (approximately at the level of controls). The impaired FCD following endotoxin challenge was improved by dopexamine in the longitudinal muscle layer (+33% in DPX group versus LPS group; P < 0.05) and in the circular muscle layer (+48% in DPX group versus LPS group; P < 0.05). In DPX group, dopexamine administration reduced the number of firmly adherent leucocytes (-31% versus LPS group; P < 0.05). Plasma levels of tumour necrosis factor-α were reduced by dopexamine infusion (LPS group: 3637 ± 553 pg/ml; DPX group: 1933 ± 201 pg/ml) one hour after endotoxin challenge. CONCLUSION: Dopexamine administration improved IMBF and FCD (markers of intestinal microcirculation) and reduced leucocyte activation (a marker of inflammation) in experimental sepsis

SDSS-III Baryon Oscillation Spectroscopic Survey data release 12 : galaxy target selection and large-scale structure catalogues

The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets for which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large-scale structure catalogues for the final Data Release (DR12) samples and the associated random catalogues that quantify the survey mask. The algorithms are an evolution of those used by the BOSS team to construct catalogues from earlier data, and have been designed to accurately quantify the galaxy sample. The code used, designated mksample, is released with this paper.Publisher PDFPeer reviewe

Dengue virus genomic variation associated with mosquito adaptation defines the pattern of viral non-coding RNAs and fitness in human cells

The Flavivirus genus includes a large number of medically relevant pathogens that cycle between humans and arthropods. This host alternation imposes a selective pressure on the viral population. Here, we found that dengue virus, the most important viral human pathogen transmitted by insects, evolved a mechanism to differentially regulate the production of viral non-coding RNAs in mosquitos and humans, with a significant impact on viral fitness in each host. Flavivirus infections accumulate non-coding RNAs derived from the viral 3'UTRs (known as sfRNAs), relevant in viral pathogenesis and immune evasion. We found that dengue virus host adaptation leads to the accumulation of different species of sfRNAs in vertebrate and invertebrate cells. This process does not depend on differences in the host machinery; but it was found to be dependent on the selection of specific mutations in the viral 3'UTR. Dissecting the viral population and studying phenotypes of cloned variants, the molecular determinants for the switch in the sfRNA pattern during host change were mapped to a single RNA structure. Point mutations selected in mosquito cells were sufficient to change the pattern of sfRNAs, induce higher type I interferon responses and reduce viral fitness in human cells, explaining the rapid clearance of certain viral variants after host change. In addition, using epidemic and pre-epidemic Zika viruses, similar patterns of sfRNAs were observed in mosquito and human infected cells, but they were different from those observed during dengue virus infections, indicating that distinct selective pressures act on the 3'UTR of these closely related viruses. In summary, we present a novel mechanism by which dengue virus evolved an RNA structure that is under strong selective pressure in the two hosts, as regulator of non-coding RNA accumulation and viral fitness. This work provides new ideas about the impact of host adaptation on the variability and evolution of flavivirus 3'UTRs with possible implications in virulence and viral transmission.Fil: Filomatori, Claudia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Carballeda, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Villordo, Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Aguirre, Sebastian. Cedars Sinai Medical Center; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pallarés, Horacio Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Maestre, Ana M.. Cedars Sinai Medical Center; Estados UnidosFil: Sánchez Vargas, Irma. State University of Colorado - Fort Collins; Estados UnidosFil: Blair, Carol D.. State University of Colorado - Fort Collins; Estados UnidosFil: Fabri, Cintia. Instituto Nacional de Enfermedades Virales Humanas "Dr. Julio I. Maiztegui"; ArgentinaFil: Morales, Maria A.. Instituto Nacional de Enfermedades Virales Humanas "Dr. Julio I. Maiztegui"; ArgentinaFil: Fernandez Sesma, Ana. Cedars Sinai Medical Center; Estados UnidosFil: Gamarnik, Andrea Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin